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MG MGB GT V8 Factory Originals Technical - Why aren't V8 conversions faster?
|1st thing; no offense intended to anyone. I respect and admire all the hard work and $ you gentlemen put into your cars, and some are indeed works of art.|
I'm in the planning stages of a V6 conversion, and while dreaming of the performance gains I hope to achieve with 200 HP in the 2200 lb MG, I'm confused why the V8's, some with 300 HP (Dale Spooner, etc..) don't run faster in the 1/4.
I'm referring to the info shown at the 1999 V8 convention site showing Dale Spooner's top 1/4 mile speed of 102. I understand the rear end ratio's, etc... play a big part, but some have better rear end ratio's than Dale's; is it the lack of posi?, or am I missing something completely? (I assume these were 1/4 mile speeds)
I've been to a couple statistic sights showing:
Camaro Z28; 320 HP, weight 3400 lbs, 1/4 mile @ 105 mph
'99 Corvette; 345 HP, weight 3300, 1/4 mile @ 108 mph
Mustang GT; 260 HP, weight 3400, 1/4 mile @ 100 mph
BMW M Roadster, 240 HP, weight 3100, 1/4 mile @ 102 mph
I don't know if these figures are totally accurate, but they seem consistent across a few different sites.
Are there other MG's out there that are running faster? I know with my V6 conversion, I'm not going to have a race car; that's not what I'm after, I was just curious why our light weight MG's weren't faster. I'm sure there's more MG performance stats I havn't seen, so apologies in advance for my ignorance.
|Steve, one major constraint on most MGs is that we just can't get wide enough tires on there to put the power down, posi or not. Also, unless you carry out mods to the car's body, the air induction at WOT is not spectacular. Painful, but true! Still, most bigger-motored conversions (Rover above 3.9 or Ford 302, etc.) can finish a quarter at 100, though, assuming a competent driver. A lot of people, including myself, choose to gear them with tall gears for effortless highway cruising. It would make a BIG difference if you put a 4:11 rear end under an MG and significantly bigger tires! But to be fair to your point, the small Chevy and Ford 302, esp. the heads, have simply been taken to a level of development that the Rover really hasn't. I know I will draw some fire for that admission, but let's be real.|
|Check out the 50 Fastest Musclecars site at: http://members.tripod.com/mork_04/50htm|
102 MPH in the 1/4 puts the MGB V8 in the top 50...not too bad.
|Michael S. Domanowski|
Corrected address: http://members.tripod.com/mork_04/50.htm
You missed the period between 50 and htm. A couple more good sites for performance specs:
The muscle car site didn't have other fast cars, like porsche, etc..
Anyhow, I appreciate the responses, and Bob's comment sheds some light; however, I still don't see why, say the BMW M, weighing 3100 lbs, should keep up with our 2200 lb car, if the MG is even decently equipped/geared, etc.., surely the BMW can't have that much wider tires, or does the extra weight actually help the HP work?
|I see one fault. All my specs show the MG weighing in at 2500-2600lbs. Then add a driver and fuel. That in conjunction with puny 195 or 205 tires does not make a good combination. |
You fail to quote times. MPH means nothing alone. We need times. A 97 Porsche 911 Turbo does the 1/4 mile @ 108MPH, but it's time is 12.9 (actually one of the above links shows it at 12.2) sec which put it in the elite category.
|I ran a PC simulation that was based on weight, drag, HP, torque, tire size, weather etc. best I got was like 13.1sec@104mph, that was with major wheel spin and an optimized take-off.. It all ties togehter, vehicle weight, HP, torque, gearing, tire size and compound etc.|
a MG's 205/50r15 tires , vs a mustang or vette with 245 or 255's is no comparison.
What I found interesting was that when simulated on the road course at laguna seca, my mock-up car out ran the Mustang (I took the mustang's engine stats and put into the 1980 MGB chassis) by a few seconds each lap.. THAT is fun to see, the lighter weight seemed to correlate into a little more speed in, during and exiting the turns....
|Larry, how was the car "prepared" in your PC sim? Rover 4.6? Ford 302? What software package is this?|
|Quick,somebody give me some fat tires,a std transmission,a posi rear,gears perhaps a little friendlier than my 2.76's,and a real dragstrip cause I got an itch to scratch.........|
|Michael, not to be argumentive, but;|
Others will have better specifics on different models than I (and please correct me, and/or add to model weights everybody), but I'm showing 2300 lbs for MGB's, generally. I assume the BMW-M roadster published curb weight does not include driver/fuel either; Therefore, an 800 lb difference. Also, I realize that there are many variables to 'speed'; I could have listed the times also; But your Porsche 911 example does nothing to negate the premise of my original question: Why isn't a 300 HP, or 250 HP, 2300 pound car (properly rigged, as many are doing), why are they not faster than a much heavier car with similar HP?
Your points are well taken; I was, however, talking about HP figures/speed figures in general, compared with the associated vehicle weights. I realize the different gear ratios, and the valid purposes for each choice; nor is the induction method/limitations, nor Ford vs. Rover/BOP what I was asking. My question is strictly on general figures, HP x weight = speed, all things else fairly equal; I'm guessing that some of the V8 gentlemen have optimized their drivetrains to some extent.
Thanks for the info; I realize speed/handling is a total package, and I don't expect I'll achieve the optimum in either catagory with a V6 conversion; my original question was simply out of curiosity, and what I could achieve in minimum terms of power vs. weight, given published data I've seen. If I achieve 200 HP, and make my car handle nearly as well as some of the experienced owners on this forum, I'll be well pleased, regardless of what cars I can 'beat'.
Final Word, promise; I know 102 mph is very fast, plenty fast for me in fact. My original question may not have made that clear.
| Hey Dale you can borrow my car if you want!|
|Mr. Dale Spooner,|
You're sassing me..... right? (a quote from 'American President', starring Michael Douglas).
So you know I'm a real person; soon, you'll be getting the advertisement from Superstore Furniture, Williston, (with the metal key taped on) you'll note the bulk permit # on the envelope; Schererville, Indiana; That's me. I've been to Williston several times, drink my 'tea' at "Evergreen Eddie's"; and would love to see your car.
Dale, I hope you don't take any offense at my earlier
I'm a relative novice both in MG's and performance cars in general (I do have a friend with 2 Vipers, 1 with, 1 without top), but I am eagerly researching everything I can on my more plebian effort at a decent running MG V6.
|The proggy was cartest. I had the stock 1980MGB file, but swapped out the motor and trany data for the data from the Mustang GT, since I am doing a 302 conversion..|
I was a little off, I showed 101.9 @1/4mile. time was high 13second range..
I then did a side by side "dragrace" with a select few cars, 93 Covette ZR-1, Tyoytal Supra turbo, 98 Mustang GT, 93 TRans Am GTA. Results after 1/4 were: ZR-1, MG 302, Toyota, Firebird, Mustang. The 100ft was intersting, the MG 302 was fastest...
|First off, I drove Dale Spooner's MGB on one of those 1/4 mile runs. His car is faster than those numbers look. But it ain't no drag car. With 2:73 gears and an automatic without a high stall converter the first third of the run is wasted getting the car moving. Like he said, give him better gears, a manual trans and some traction and he'll pick up 3-5 mph.|
That said, I don't think the numbers are too far off. Car and driver weight combined, (help us out here, Dale) I'm betting about 2750 lbs. Give him another 3-5 mph. and your looking at 105-110 mph in the quarter. That's pretty damn fast compared to your average grocery getter!
As a comparison, my '68 Camaro pushes about 400 HP (Chevy power, Dale), weighs 3230 car & driver, runs the 1/4 mile in the 12's at over 112 mph.
|Well, I finaly found where I got it. There are 2 versions, one DOS shareware (which I use) and he now has a new and improved version.|
I found it very nice that he had the MG RV8, 1980 MGB, and 1993 MGF(in 2 forms)
Acceleration is more than an issue of power vs weight. Traction of the tires plays a part, and the wheelwells of the MGB don't accept very wide tires. Although there are very sticky high performance tires available, they have short tread lifes and high purchase prices. Most owners are somewhat economy-minded and thus don't maximize in this area. Weight transfer under acceleration can also be an issue as the MGB has a low center of gravity and thus doesn't have as great a propensity to "squat" on its tires like many other cars. So why build a V8 MGB? Certainly not for doing stoplight-to-stoplight drag racing. Any pimply adolescent can do that, and that's mainly who does it (No insult intended to those present. Serious strip racing is great for those adults with the expertise and budget to do it) So why build it? Just imagine looking down at the tachometer at 70mph and seeing only 2500rpm. Imagine going up a very long, very steep hill as if it was flat. Pass that slow driver in front of you? Effortless! By the way, that cast iron chevy V6 anvil will bias the weight of the car so far to the front that it'll understeer terribly. If you do decide to install it, don't forget the flame paint job, greaser hairstyle, the pack of Luckys rolled up in the sleeve of your T-shirt, and the fuzzy dice to hang from the rear view mirror. Oh yeah, don't forget the playboy bunny sticker in the rear window. No bastardized hot rod is complete without it. Gentlemen, proceed to the flame wars section.
|Tire size,traction,etc.all being equal,is a 150bhp-1500lb midget the same speed as a 300bhp-3000lb car?|
If you want to blow away Bob in the Camero, then climb into the Viper! We're missing the point that made the BV8 legendary. The raves were, and are, given to (I think) the cars' balance and pure enjoyability! There is no question that one could build a B to blast out of the hole (with a little modification and cost--more than just $$) based on numbers etc. The key, for the road car, is seemingly endless torque and the handling as present in the original state. Think of the roots of the conversion and the simplicity with which it was done. That was news! If spending a lot of time at traffic lights next to throttle-blipping testosterone junkies realy bugs you, then spend your money on a '69 Camy that can't turn corners! Numbers don't say it all unless you have all the numbers! Let the B comb your hair.
|Oh,... and don't forget to stop and smell the flowers!|
|The V6, 90 degree 3.8l or 60 degree, weighs little more the the 4 cylinder, and can be set back farther in the engine bay. The front/rear weight ratios are nearly the same, so massive understeer is unlikely.|
Costello and others in the U.K. installed the V8 in B's before the factory ever did, so present day swappers, whatever engine they choose, are no more bastardizing the marque than did the earlier swappers. Serious swappers could less about the silly assed customising accoutrements mentioned, as well as stupid 200 Watt sound systems that don't sound as good as the engine does anyway.
|I'd like to correct a misconception that the V-6 motor is heavy. According to a friend who pulled his entire drivetrain and weighed it, an MGB 4 banger, complete with clutch and tranny, weighed in at 477lbs. According to Jim Pace GM Parts Wharehouse catalog, a complete 3.4L Camaro V-6 (cast iron heads) weighs 325lbs. Add 85lbs for the 5 speed and, say, 50lbs for the clutch, etc. and you're still only at 460lbs. If you go the front wheel drive route with aluminum heads you can save 40lbs or so. Doesn't sound like an anvil on the front to me. My "B" with a '94 Camaro FI V-6 actually raised a little on the springs when the engine was installed. Theoretically, then the handling should be the same as the original engine. And the weight distro should still be in the 50/50 range. |
My original question was in no way intended to flame the successful V8 conversions out there. If you read my posts, you'll have to see that I have the utmost respect for the hard work and ingenuity needed to accomplish what they have. My question was a genuine interest in why a 300 HP MG didn't run faster than a 3500 pound car with 300 HP. Several responses shed some light on this subject for me, and I thank all serious responses. Personally, I'm not after 300 HP, don't care if I can 'beat' a Camaro, don't want flame colored paint, and don't have much hair to grease up.
The positive points you mentioned about the V8 conversions are what I'm after, although on a more modified scale with the V6, I realize. I do intend, though, to have a decent stereo system, as driving down the road with my favorite Bob Marley, Fleetwood Mac, Hendrix, etc.. blaring, with the top down, is one of the pleasures I've become fond of, even with my limited MG experience.
Regards to all,
I think I gave a reasonable explanation as to why to MGB has its problems in a drag race: low center of gravity reducing weight transfer onto the rear wheels, small wheelwells keeping treadwidth to a minimum, etc. The very nature of your question led me to believe that you were one of those who are interested in a hot rod conversion. As to my remarks about the hot rod image of V6 conversions, perhaps I owe an explanation to those who buid them. Whether we choose to admit it or not, the MGB is a vanishing classic car. The last one left the factory over twenty years ago and many, many of the ones still left are in a sorry state. In ten years time there will be far fewer. Hopefully they will come into the hands of those who appreciate them for what they are: historic classics. Note that the title of this particular Bulletin Board is "MGB-GT V-8s and V-8 Conversions". There is no Board for V6 conversions as this website was created to help people preserve the marque, not to facilitate those who would butcher, bastardize, and destroy its dwindling remaining examples. When an outsider enters the sanctum of others with the intention to perpetrate what they view to be vandalism, he has no reason to expect to be made to feel comfortable. I know this seems harsh, but the truth is that a 1941 Cadillac LeSalle with a Chrysler Hemi engine and a Ford rear axle assembly is no longer a LaSalle at all, it's a hot rod. It is also one less example of a classic. If you wish to build a hot rod, you're welcome to. However, don't feel outraged if you're viewed by some in much the same way as a political protester from "Queer Generation" picketing a church. This is America. You're free to do what you want. Hopefully, you won't do any irreparable harm.
|Paul Kile mentioned in one thread that he had the webmaster create this board for MGB V-8s only, but that there was so little response that it was opened up to include V8 conversions to keep it active. The MGA V8's and the V6 conversions do no detract from that aim.|
I don't recall Rover being on board when the MGB was designed, so I fail to understand why installing a Rover engine in an early roadster should be considered any less of an abomination by a purist than would be the installation of, for instance, a Honda or Acura engine, as Honda had a stake in MG's for a while.
Just about any V6 can be installed in any MG with no irreversible changes, and some of the five speed transmissions fit better than an overdrive unit.
This is NOT a Holy site, it's a place for motorheads.
|I meant to say the board originally was MGB-GT V-8s only.|
With Heritage shells and with modern communication of parts availlability, it is easier to build a brand new MGB than it was twenty years ago, so I don't think this classic is an endangered species.
|I have a 72 B roadster that looks like a stock M.G. that weighs in at 2,460 lbs. with me sitting in her & I am 240 of them there lbs. I have a 4.9 with a T56, 6 speed, 205X60-15 tires. I can do 13.5 1/4 mile day in & out on pump gas. There are things I could do to make her fasrer BUT, she has NEVER left me in 4 yeare running! There is one thing that is on my M.G. that I have not seen on a vett. tang, camaro or a B.M. of a W. & that is a TRAILER HITCH!!! I pulled a U-Haul 4x8 trailer to Clev. Oh. last year with over 2,300 lbs. behind the car & I do not slow up just because there is a small trailer back there! We did 1,500 miles that weekend. If I were to put the money into my M.G. that had to be spent for the go fast cars, she would be a LOT FASTER. ( A GOOD RIDE IS NOT HOW MANY STATES YOU GO THROUGH, BUT HOW MANY TIME ZONES YOU GO THROUGH)|
|Well put Glen!|
Hey, please send me an emal about how you went about installing that hitch. I have a small custom trailer ready to be built, but have to get a hitch on my '78B before I bother starting that...
According to the Haynes manual, the stock MK II cars had a maximum permissible towing weight of 1,680 lbs. Not bad for a 1.8 liter engine!
Heritage shells are built into complete MGBs on custom order by at least two companies over in the UK. When I finish my present project (1972 Roadster), the next one will be a Heritage bodyshell with a Rover V8. I'm such a gearhead that I even intend to take a night course in auto painting so I can do the paint job myself! I doubt that such efforts will slow the disappearence from the road of the increasingly rare MGB. The fact that Rover was not part of BMC when MG designed the B Series hardly matters. MG did in fact put a Rover V8 equipped B into mass production, although it was only in GT form. A V8 roadster was considered, but objections from Jaguar and Triumph prevented its introduction on the assembly line. Late in the car's life an O-series engined prototype was built, but all MGB production terminated before it could be introduced onto the assembly line. MGBs modified to accept such engines are considered to be MGBs by all but the most radical of purists, of which group I am not a member. I am not a Concours judge. I don't care if you use SU HIF4 carburetors on an early model B. However, a V6 engined MGB is, in my opinion, a hot rod, a radical departure much like a Ford Model A with a Corvette engine. Some of these cars are well engineered, an expression of the master customiser's art. But they are "fringe element" vehicles. They are hot rods, not Ford Model A's or MGBs. As I said before, if one wants to build a hot rod, let him do so. But if he is a realist he should be aware that he will be viewed and treated like any other member of a fringe element: at best, with polite and somewhat condecending tolerance by the open-minded, at worst, with hostility by the bigots. Such is real life. Above all, be free. Choose your own path and walk it. I do. Godspeed.
|I wish all you owners of factory MGB-GT V-8s, and FAITHFUL reproductions thereof, would quit posting ... you're cluttering up this board for us poor hotrod bastardizers! Actually, I'm just a wannabe bastardizer. Is that even a word?|
In any case, thanks for the history lesson, Mr. Strange.
Outsider, Living on the Fringe
|And just where would you wish us to post? After all, it is our board. What nerve!|
|Peter, My comment was in jest! The point was: how few, as a percentage, of the posters on this forum are factory V8 or FAITHFUL reproduction owners. If those were the only people who posted, this board would be pretty empty; in addition, much valuable information would be lost (that which is posted by the fringe element - according to Mr. Strange), on all subjects concerning V8s, or MGs in general.|
A factory V8 or well-done reproduction is not a posibility for me right now, and the car I'm 'bastardizing' would have ended up in the wreckers, so I don't think I've hurt the future of the MG.
From what you say you seem to think that "factory V8 and Faithful reproduction owners" are in a very small minority of posters on this board. You also seem to believe that without people such as yourself that "much valuable information would be lost...on all subjects concerning V8s or MGs in general". Those of us who build faithful reproductions are the ones who provide the accurate information that keeps the cars running in good order. Do you honestly believe that people such as yourself make up the majority of contributors to this board? Peter is right. What nerve! You meddlesome egocentric Yanks never seem content to leave good things as they are.
|OH Boy, Oh boy. This is what i've been waiting for. Yanks vs. Limeys vs. Aussies. Who will win this battle of the Titans:) |
Life's too short have fun:)
Let's not be too harsh with Steve Watson. After all, we are civilized. Customizing one's own car is, to Americans, something of an expression of freedom and individuality. It's an old American characteristic that sometimes when an American chooses to do something, he becomes single-minded and his thinking becomes that of "Cogito Ergo Est" (I think, therefore it is). He has difficulty in comprehending the attitudes of others who see his actions as desecration of a cultural icon and believes that not only is he is in the right, but that the majority is with him. Our country has many organizations comprised of such people, such as the Michigan Militia, Ku Klux Klan, and Queer Generation. That having been said, in the end it is his car, and there's nothing we can do to dissuade him. Above all, let us be civilized.
|Can't we all just get along!??|
There are VERY good argument both side of this issue, so lets just leave it as agreeing not to agree and move on. I also think one person was poking fun and people did not catch it and are thus cranky..
Stephen hit a few points. 1. it is a CAR 2. We yanks love to modernize or otherwise make our cars "ours" by making changes to suit ourselves. SO?
I LOVE my mg, I bought it BECAUSE it is an MG. If I just wanted a hot rod, I could have VERY easliy and cheaply (much cheaper than what I am spending now) a Mustong convertible and been on my way.. BUT I wanted a MG, they have a charm and elegance all thier own. PLUS, they are damn easy to fix yourself. I was going to do the traditional Rover transplant, but lack of available parts and $$ Rules that out, so I am doing a 302 conversion. Does this make it no longer a MG, hell no, I am keeping the chassis intact (FULLY). If that is no longer and MG, niether is any other replacement of parts, be it axles, suspension, engine, etc.. Now, I don't think taking a nice all OE MG and converting it is a good idea either. We DO need to maintain specimens of the factory original breed, but I see enough of those at each club meeting to know that base is covered well. My goal is to increase knowledge of the breed by getting everyones attention (in a good way) and getting them interested. If not for V8 conversions, I KNOW we would have many 1000 fewer MG followers here in the US alone. Just having the cars out of the road gets us noticed and is good for the breed.
(OFF SOAP BOX, and out of breath..)
|Wow! Great friendly argument developed from a simple question from Steve.|
My 2 cents worth on this subject, 1. MGís chassis was made to handle corners, as stated by Stephen S.
Weigh transfer to rear wheels, rear suspension type, front suspension set-up, among several other factors is what makes a drag car. 2. We Americans are not the only ones who like to swap engines into British cars, Jensen Healy Big Chrysler engine, TVR Ford /260289, Alpine Tiger 260/289 Ford, Jaguar Lister Chevrolet V8, AC Bristol became the Cobra, MGB GM V8, and there are others. The difference is that these cars were produce in large numbers to be called originals for the purist, I like to think of it as improving the breed.
There is no right or wrong in swapping engines into a car that you like. Itís a personal taste like the (Shorts) underwear pants you prefer.
3. There is nothing wrong with some humor and laughter lets get along and share information that can help each other in our car projects.
BTW I have a friend who got tired of high maintenance cost on his 300 SL RD. He install a 350 TPI -LT1 Chevrolet engine from a Corvette with a six speed trans. The car is faster but the value of the car went down, the must important thing is that now he really enjoys driving the car on the daily basis, that is more important to him. The car becomes more valuable to the owner.
He was asked not to renew his membership in the Mercedes Benz car club, which he was glad not to renew his membership. Just imagine Jeffís car could be the only one in the world, now! Thatís original.
Right on man! If those Mercedes folks were to stuck up to allow someone with a modified car in thier club then it is obvious they are in the club as a status issue, or just plain and simple stuck up. Since only a fairly affluent person can afford a Benz especialy a factory original/restored older one.
No offense intended, but to me it seems obvious. We have people like that in our (large) local MG club. BUT while they may not like the conversions, they do realise that at big car shows, the conversions and customizations bring much attention to the marque which is the whole goal, to PROMOTE the marque. And the more we share info on good ways to convert things, the more high quality conversions we will see...
|A few final thoughts;|
My original question was sincere.
My respect, both for FAITHFUL reproduction owners, and other successful installations, is genuine.
I'm saving an MG from the wreckers; would you rather it sat rusting in the wreckers waiting for some far off day, if ever, that a factory V8 owner needed a part from it?
I don't think a non-marque-approved modification to a car headed for the junkyard puts me into the classes of people Mr. Strange speaks so highly of, either.
I am not in the group of people whom I referred to as contributing valuable information. I'm not even to the novice stage yet; I'm learning, not teaching, and I've admitted such openly, several times.
Finally, and just for clarification, where do you 'protect the marque' people draw the line? Assuming you have a Buick or Rover engine; does it matter which engine?; do you need a particular intake, or carburator; and what about exhausts, are headers taboo, dual exhaust or single?; transmissions? It must be tough on you purists, what with all your comrades peering over your shoulder, lest you commit an infraction!
Myself, I plan on many happy years in my 1st MG, and I wish the same to all of you, purist or otherwise.
|Steve, go ahead and build the car you want. Anyone who has to build a car which is exactly stock needs professional psychiatric help. I have a V8 conversion and it's nowhere near stock, and I would surely like to lift the hood on your car when it's finished, and spend a while talking to another car nut. Gentlemen, live and let live!|
|FAO Michael H;|
"Yanks vs. Limeys vs. Aussies"
Yep, thats us New Zealanders, faithful Aussies till the end. or not.
I guess they just dont teach geography in Canada any more.
|Well I have had a factory V8GT for 17 years albeit progressively modified in the interests of improved performance, braking, electrics and handling. I also built one of the first V8 GT conversions in the USA back in 86 on one of the rare late 74 rubber bumper GTs. Since then I have built a V8 Roadster on a Florida car and brought it back to the UK with me. Developmment goes on - Panhard rod, front suspension etc etc.|
The point about using the Rover nee Buick V8 for a conversion is that it is fairly easy to do. As I understand it GM V6s do not have a good reputation.
For the benefit of the apparently geographically challenged US contributors to this thread, I am in England
which our current government has allowed to remain part of the UK (and the roads do not all run in straight lines - unlike Florida!)
|David Daw writes:|
"Anyone who has to build a car which is exactly stock needs professional psychiatric help."
Well, I always wondered about that, now that I am putting the finishing touches on my totally stock Factory GT V-8....after all, SOMEBODY has to preserve a stock example, if for no other reason to preserve the Factory faults and mistakes for all of us to enjoy!!!
They're coming to take me away, ha ha, they're coming to take me away ha ha ho ho he he....to the Funny Farm, where life is beautiful all the time, and I'll be happy to see those nice young men in their clean white coats and they're coming to take me away HA HAAAAAA......
Kile, Paul D.
Ward 3, Bed 7, Bellevue Hospital
Gibbering and drooling and constantly making twisting motions with his fingers as if tuning an imaginary set of SU carburetters....the Thorazine helps with this.
|I know I keep promising I'm thru with this thread, but it's just too much fun.|
Picture this, if you will:
An international purist convention, bright sunny day, beautiful green meadow, all the purist cars in a tight circle, front bumpers facing in, hoods-bonnets up, each purist standing in front of his own car (the nicest one there, naturally), funny little authentic cap-hat on, zippers down, furiously having the classic circle j**k; well, you get the idea. Some people's idea of heaven, I'm sure. Be careful gents, you wouldn't want to soil that shiny air cleaner cover!
Geez, I wish spring would get here.
|Actually, building a 100% factory-correct car must be a far more daunting task than most people would realize until they stop and consider what really goes into the work. (Now let's see... where can I find an authentic 1968 widget bracket? That was the only year they had the reverse tab on the left side. The previous year they were Mars Black and the next year they were Pitch Black, so mine might be? Hmmm... Where's my copy of Clausager's Original MGB? Drat, the photo doesn't show it!) Building such a car has got to be far harder than cobbling together a hot rod. Do such dedicated builders need to see a Psychiatrist? By the time they finish the project they probably do. It's only too easy to substitute an easy-to-find later part than spend years searching for the original part. If anybody ever notices the change, you can always smile and call it an "upgrade". Almost everybody does it from time to time. The dedicated purist is not unlike a knight going on a quest for the Holy Grail. He's to be admired for his devotion, not denigrated.|
|Wow, what a thread! I havenít seen such strong reactions since there was a suggestion on the MGB BBS to paint rubbers to match the body color. Oh, and one other subject in the MGF BBS that I wouldnít dare bring up.|
I was fortunate enough to attend the MG car show in í96 where the V8 was the featured marque. After drooling over an original MGB V8 I moved to the next one identical except for color, then the next one and the next one. I loved each one, but the dozen conversions provided more variety, which held my interest from car to car. Next I looked at the Limited Editions, IMO the best looking rubber bumper versions, but again I found myself skimming past the cars that were so much the same. The owners must have memorized their license plate numbers to avoid the embarrassment of trying to start the wrong car!
My ideal car show would be the contributors to this BBS from the wildest iron blocks to the nearly conventional Rover/BOP to the V6ís to the perfect example of the original MGBGT V8 built by Paul Kyle.
Had it not been for Ken Costello daring to put non-MG motors into MGBs, BL may not have been inspired to produce factory models. Likewise, it was probably Roger Parkerís successfully engineered use of a fuel injected Rover and its 5-speed transmission in his roadster that lead Roverís management to develop the MGR V8. An MGR V8 should also be at that ideal car show.
So, thanks to the innovators and dedicated preservers alike.
You zay dot you vant to put somesing into der bowels uf your car zat was never intended to be zair? Und you haf a fantasy uf a bright sunny day in a beautiful green meadow vis a group of grown men masterbating together? Zat zis is somebody's idea uf heaven? Zen you zay dot you vish dot shpring vould get here? Bubi, hoo boy, you got problems.
I think I have I suggestion that might resolve the conflict between the "Ultra-Purists" and the "Hot Rodders". We all know that a botched conversion is a disaster for both parties because it is only logical to presume that some cars are lost forever due to incompetent, unsafe conversions. Roger Parker created a website specificly to prevent this in the case of V8 conversions. It can be viewed at http://www.mgcars.org.uk/v8_conversions/rogv8.html If in fact a proper GM V6 conversion is reversable without modifications to the bodyshell, why not have those who claim to have done such SUCESSFUL conversions post their Email addresses on a new thread, correspond with each other, and create a website patterned after that of Roger's showing just how to do it properly? That way the purists will no longer wail at the butchery caused by incompetent, unsafe conversions, and those who desire to make such conversions will be able to do them without ending up with a disaster. I know that such a website would take time and effort to create, but at least such a compromise would stop this bickering on both sides.
|My personal subjective unsubstantiated biased opinion over the last few years is that the horsepower ratings for the alloy BOP engine are overstated. The design is renowned for being compact and light but not a paragon of head design and horsepower per cube of displacement. The valves are not large. the combustion chamber and ports aren't modern, the intake system is squeezed under a too low hood and was considered poor in 1964. The pleasure of driving up a 7% grade in top gear at 70 + is there. The pleasure of feeling a modern dohc v6 winding past 7000 rpm and still pressing you back in the seat is not there. |
My kid had a ford mustang 5 liter with a little work done - allmost stock. I had a Taurus SHO 3 liter dohc with a little work done, almost stock. Same weight, same rated horsepower. The Mustang would yank you back in the seat at each shift at 5500 rpm, like a hammer and felt far more powerful. With rear wheel drive it was also faster off the line. The Sho wound between 5400 and 7400 rpm each shift and would pick up 25 feet on the Mustang each shift. With the better aero above 90 mph the sho took off and it was no contest. Moral of the story -- hi cube engines (per car weight) feel very fast, but at the end of the day its the area under the horsepower curve that produces the performance. An engine that has a hi peak horsepower but drops off quickly will not be as fast as an engine that has less peak horsepower but maintains it's horsepower output over a wider rpm range. Modern v8s put out hi torque from low rpm to max rpm. No peaky race cam stuff. The average hp through each shift is what it is all about. It's also a personal choice between the torquey sock in the back or that dohc engine that just seems to wind forever. Now that I've got my 67 gt going with its full 1844 cc's, I'm ready to finish off my modified B and the Nissan 3 liter v-6. This fall it should see the road - finally - maybe I'll have that sock in the back and the engine that winds up forever.
|Steve and Barry, you both hit things on the head.|
Steve the website idea is great. when I started my conversion I had planned to do it without any mods other than the crossmember (which I have a spare of). I have found out that I will have to do more chassis mods to get it in. That bums me out,but at the same time I realized that once in I highly doubt I will ever want to go back the the stock engine and I will probably never sell her, so it is bothering me less now.
Barry - your information is one of a few reasons I chose the 302 rather than 215. I have local friends with BOP conversion and they have lumpier cams to get the HP out of them. my block will be BONE stock with a very mild cam and should just pull, pull, pull..
|Back to the topic, I must say that in my experience traction and areodynamics are big factors with MG V8s. Above 100 mph and top down the turbulance is great and the front of the stock mgb begins to lift up, at least in my car. From a rolling start my car can out accelerate a brand new corvette, but from a stand still all I end up doing is spinning my tires if I really step on the gas. Another friend of mine has a 94 corvette and the only way I could out accelerate him was to start in 2nd gear and simply match his acceleration until I could shift to 3rd. I feal the only way to be able to use 1st or 2nd and really stomp on the gas is to use slicks- or add a ton of weight in the back.|
As an aside, why do these posts always seem to stray off course? Sometimes people who want to contribute to original post don't because it is no longer relevant.
- you guys can continue bickering amongst yourselves now :-)
|Bob Pulleyblanc, the V6 has a great reputation in the racing arena, and car enthusiast in the US, in fact is the same engine that it's used in the Opel in Europe with the exemption that it has more HP than the American version. GM also makes an all alloy block for the serious racer.|
I converted a 1970 RD with a 215 V8 from a Buick that I bough for $75 in 1978 I had no idea that these car existed with a V8 in the UK.
If anyone needs help in converting his or her MG to a GM V6 just e-mail me. The kit for the 302 V8 will be ready sometime in Dec. I will share my experiences with anyone who wants to convert their MG.
Engine swaps are great and fun to do.
BTW I will be converting an original 67 GT to a Chevy V6 with a T5 transmission this summer. With all the parts on hand it should take a 3-day weekend.
No other mods will be done to the car, just the engine and trans.
Larry, stock 302 4V with a 270/280 duration, 440 to 500 lift on 107 degree overlap and 112 degree lobe separation, should give you over 200 lbs of torque. If you add alloy dual plane intake manifold with a 600/650 cfm carb and with the correct headers add another 20/40 lbs of torque. Add alloy heads and....
This torque would be in the lower rpm range all the way to about 5500 depending on valve spring and valve size. That is another story.
A stock 2.8 with a good cam manifold, carb, and headers, can produce over 160 lbs of torque and is capable of 180 lbs of torque. More torque if the 3.4 liter V6 is used.
Thanks for info. I got my block rebuilt by a local Ford nut. most I know is that it is +.030, with flat-top flycut pistons and a 260Dur RV cam. I told him, make it a strong engine, but that it had to idle all day long without loading up or lopping. I have a edlebrock performer intake and Holley 600 4bbl carb. Stock heads with exhaust bump removed. I have been told to expect roughly 275hp and 275-300ftlbs torque. I am considering taking it to a dyno before finally mounting it in car so I can really know what it puts out..
and I wish you would hurry up with that blasted 302 kit!!! :-)
|Yes! RV camshaft does the same as incresing the compression on the engine, and the best part is that it gives it all in the low rpm's |
Low duration high lift with narrow love centers,Great street cam! You are going to have a great MG Larry, hope to see it someday.
|I hope you see it to!! Yeah that and the flat-top pistons should put the compression pretty high (reltive term) I am pretty sure I told him regular pump gas too hehe probably run mid-unlead or premium in it anyway..|
From my calcs. I should cruise at 60mph on hwy @2250rpm hehe mathmatically with a 5500 max rpm put it ~140mph..
|So what's the problem with a v6? My 73 roadster is in the middle of getting a ford 2.8 v6 with a 5 speed tranny. The firewall is not being cut, the radiator stays where it was, the car will actually be lighter, and economy will be better than a big v8. Oh, and lastly, this car will still go like a bat out of hell.|
|Sounds good to me Alan! It all comes down to what you want really. I am willing to bet your car will keep up with my big burly V8 also. you getting a SVO motor from a stang?? they get some insane HP out of those thing now...|
|Alan, nothing! is wrong with the Ford V6. The only problem you may have is that it can be faster, and handle better than some V8's.|
|Guess I must be *way* out there in the fringes. No new news here. Bigger tires do help quite a bit. 265/50-14's will fit, but you have to find a way to make the body 6" wider if you don't want to cut the fenders and just let them stick out. Done it both ways. The high compression Buick with about a 600 4bbl, a hot cam, and big fenderwell headers is good for, oh, probably around 240 hp, and with the stock axle and a wide ratio T-50 is a scary ride from the hole shot through redline in 5th. Needs a hole in the hood though. The Olds motor with the OEM turbo is almost as fast, but runs out of steam on the top end and doesn't like to just keep winding. So what's a hot rodder to do? Especially an American one from the hills of West-by-God-Virginia? Supercharge it. Add fuel injection, an experimental intercooler, and a new and much improved forward tilt assembly to ease the maintenance woes.|
Also one of the early converters, back in the early 80's it immediately became a 1 of a kind and has remained so even while the design was refined. ("It looks like a bomb!"- overheard at a meet) think it's wonderful being able to throw it into a 4 wheel drift and steer with the gas pedal. A little hard on tires.
My brother-in-law had a Spitfire with a 90 degree Chevy v6 in it. I guess it was a little squirrelly.
Anyway, just thought I'd throw some gas on the fire.
How do you make a dog go meow?
Drop em in the deepfreeze for 2 days and run im through the bandsaw: "MEEOOWWW!!!
|Boy,this was a fun read!Especially reading the rant by the laughably nationalistic Brits (who couldn't wire a car correctly to save their miserable hides!)accusing us "Yanks" of bastardising "their" cars.If the British had built better,more reliable drivetrains in the first place, people wouldn't find it necessary to alter them !Would you rather see a car cut up and modified,or crushed?I was looking at this site because I saw a 70-74 Bgt abandoned in a side lot and the car looked interesting.Is that car better served rotting away(it's virtually rust-free),or put back on the road-albeit with a different drivetrain?just something to think about.|
Now onto my main question:Has anyone tried to fit a 2.3litre turbo four and t-5 transmission from a T-bird turbo coupe into one of these cars?It would seem a better swap than a V8,with almost as much power and a distinct weight advantage.Just curious.
|The 2.3 has been done Chris...check the following link.|
This car is located here in Florida as I have seen pictures of it at my local MG repair shop. I asked about it and my mechanic says the owner has brought it by on occasion. From the pictures it looks as if the exhaust goes straight into the passenger's feet! Must get hot down there! Hope this helps.
|The Ford 2.3 Turbo and 5-speed have been done as well.|
This thread was discussed between 14/02/2001 and 14/03/2001
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