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MG MGB GT V8 Factory Originals Technical - Bigger engines

Does anyone know how the Buick 340 and 350 compare to the 300 in terms of size and weight? I realize that with a taller deck they are going to be wider, taller, and heavier, but I'd like to find out how much. Anybody have an idea?

Jim
Jim Blackwood

Don't know about the Buicks, this guy proves you can fit anything inside standard sheetmetal if you put your mind to it. I'm not sure if he left any room for his feet, though.

http://ntahc.org/modifiedhealeys/Photos/126Marian/Marian.htm

Derek Nicholson

That's one hell of a conversion. Looking at it, you'd never guess what he's got in there. But dang - I ain't EVER needed to overcompensate that much. ;)

R.
Rick Stevens

Jim, I'm certainly no expert, but I believe that the biggest issue would be with width. The redesigned heads make the engine a bit wider with the exhaust manifolds IIRC.
Bill Young

Rick, here's another you might enjoy.

http://members.cox.net/rdgrauman/Healey.html

I've got to say, those Healey guys have a lot more imagination as to what engines to put in their cars. Check them out at:-

http://ntahc.org/modifiedhealeys/

Derek Nicholson

OK, how about a 350 Buick with the aluminum heads off a '64? And don't tell me it wouldn't breathe, I have a blower to take care of that little problem. A little taller/wider than a 215 or 300, but how much?

And no more jokes about bugeyes with 600 cu.in hemis in them OK? I really am being serious here.

Jim
Jim Blackwood

Jim, check out the V8 newsletter issue before last. It featured a car in Sydney which had a SBC 350 fitted. This car was featured in our local Street Machine mag. If I can find the article , I'll email to you if you want. Barrie E
Barrie Egerton

Appreciate it Barrie, but I'm concentrating on Buick motors. I'd just as soon not have to re-engineer the conversion and the 300 or 350 block should be quite close to the 215. I know the 300 works because Mike Moore swapped it for his 215 and there's very little difference, but I'm trying to decide between a stroked 300 and a 350 short block. If the 350 is within a half inch or so on the deck height I think I can make it work, provided the aluminum 300 heads will work with it.

The key to all this is that while I was considering a T-56 transmission to replace the busted T-50, for what I'd have to spend for the tranny and adapter plate to mate to my D&D bellhousing I can buy a fresh 200-4r built to my specifications and have about half of what it will take me to build a fresh motor. Since I've had a persistent gradual loss of coolant in the existing 215 that makes even more sense. And since the 200-4r bolts directly to either the 300 or the 340/350 block it also makes more sense. And with a full manual reverse valve body and lock-up torque converter, the only real difference between the manual and auto boxes is not having to deal with the clutch which, having moved to the flatlands (compared to W.Va that is) and the city, is not a bad thing. In effect, in this configuration the 200-4r is a manually shifted 5 speed (including lock-up) with an automatic clutch. It's also a more efficient transmission than the 700r4 and smaller, but capable of handling the power.

Then of course there's the issue of the blower, but it can be adapted and with the same drive ratio but a larger displacement the boost pressure will go down, the compression can go up, and both economy and power output be increased, especially so at low RPM's and the blower can counter any breathing difficulties from the heads at high speed. The whole concept makes a lot of sense. Plus if I can pick up an old T-50 cheap I can drive the car while I'm working up the new drivetrain.

Jim
Jim Blackwood

215 and 350 engines use different valve arrangements. As such, the cams in one will not work in the other. As an added prohibition, the cam bearing sizes are different on the 215 than they are on the 350. If you REALLY want to try something like this, it would be best to start with a 340 block. It's deck is nearly identical to the 350 and it's valve arragement is identical to the 215-300. Think of the 340 as the lower part of a 350 but the upper part of a 300. It uses 350 main and cam bearings, can use 350 capscrew rods but uses a 215-300 cam. Since it's bore is identcal to the 300, pistons can be had for it quite easily. I've heard of folks boring the 3.75" holes on the 340 out to the 3.80" size of the 350 and using stock 350 pistons. So if you want to drop 300 heads onto a taller block, the 340 is your meat.... but they only built them for 2 years.

Greg
Greg

Correction! I meant to say that the 340 uses 350 main and rod bearings but uses 215-300 CAM bearings.

Greg
Greg

Then it sounds like it might work just as well to use the 300 block with the 350 crank. If the 340 and 350 used the same crank that would make it a 340, which is close enough, unless the available pistons would require a larger bore. And, it is reported that the spacers for the 215 intake are available from Australia, meaning I would only have to make a spacer for my front blower drive support. Does that sound reasonable?

Jim
Jim Blackwood

Jim, you might find useful information at the small block forum at v8buicks.com. I'm thinking about a 300 in place of my 215. I just found a 4 barrel one at an impound lot auction really cheap. I'm hoping this will be a straight in swap once I find a bellhousing and flywheel that I can use. cj in salt lake
C. Jones

CJ I think you're on the right track. There are a couple of guys with 300's (Mike Moore and Jim Stuart) and they both say the fit is near identical. So far I can't find out how much higher the deck is on a 340 block, but I'm starting to lean towards a 340 with '64 300 heads if there's room.

Jim
Jim Blackwood

" In effect, in this configuration the 200-4r is a manually shifted 5 speed (including lock-up) with an automatic clutch."

Jim,

I can't believe what I'm reading. A sissy shifter in "The Beast"?! :)

Even though I occasionally do it in my wife's Maxima, I thought manually downshifting an automatic tranny is not a good thing to do.
Carl Floyd

Well Carl, a few years back I'd have never considered it. Had a manual in both the MG and the truck. But I went to a 700r4 in the truck and it was a great improvement. Now admittedly that's not the MG, but considering that with the manual valve body shifts should be nearly instantaneous, and once in a gear it'll stay there, the main objection to an auto is gone, namely that you can choose what gear you're in. A ratchet shifter will give the positive feel when changing gears that is one of the benefits of a manual, and if I want to I may even be able to keep the torque converter clutch locked at low speeds. So all that leaves is the roll-out and coordinating leg and arm for shifts. Honestly, if I didn't feel it was going to be as good or better I wouldn't consider it.

As far as downshifting being a bad thing, I don't really see how, but that'll go on my lists of things to ask about.

Jim
Jim Blackwood

Jim, the install of a 350 crank in a 300 is possible, but VERY expensive. D & D did it for Dave Michel a few years ago. The engine was very powerful, but even with a Mike More style radiator, there were cooling issues.

You might get a quote from Dan. Many hours spent clearancing the crank, and mods to the oil pan.

The ally 300 heads are of a poor design and much porting and larger valves are required and after spending $1500+ they barely match the flow of the iron(heavier) 1965 heads.

The 200R4 seems like a very good choice. I did the research about 2 years ago as the clutch was killing my bad knee. I found a rebuilder in Florida that would supply an extra duty tranny with choice of converters and auto or manual lockup, no core, $900.00 plus shipping, and a guarntee. Do a search for 200R4. The 200 has a dual bolt pattern and will bolt to either a Chevy or BOP engine. Hurst makes a nice shifter.
Jim Stuart

Thanks Jim, very good information. Back when I was driving the car a lot I did notice a little trouble with the left knee, I had forgotten about that until you mentioned it.

I don't think I'll have any trouble with the heads, not with the blower sitting there forcing the air through. It's probably the one application where they would be adequate for a big inch engine. And since I have had a set just sitting around for 15 years or more I might as well use them. As it stands right now, I'm thinking that custom pistons will make a stroked 300 unlikely due to cost, but the jury's still out. The 300 is a good choice and it looks like the fit would be pretty easy. With the blower that should be enough horses for anyone. But it's not the power I'm after really, (at least that's what I keep saying) as much as it's the versatility of the later bellhousing pattern and the ability to decrease boost, increase static compression and stay at the same output level.

That doesn't explain going over 300 very well does it. Maybe just the challenge of something different. Plus, it looks like the deck of the 340 could be as much as an inch taller and still be able to go in. And if I'm going to a cast iron block shouldn't I go big? Probably a bit over the top though.

Now I just wonder if I could slip in an old 215 short block as the core for a 300 or 340 reman shortblock? Hmmmm.....

Jim
Jim Blackwood

Jim mentioned Dave Michel's Buick stroker... here's a link to that article: http://www.britishv8.org/Articles/MonsterMotor.htm
Curtis Jacobson

Thanks, Curtis.

I remember reading this article, but was having trouble finding it. I looked forward to seeing Dave's conversion using this engine. I wonder what became of it. Dave seems to have moved on to other things.

Carl Floyd

That's a pretty impressive write-up as well. One of the Buick guys is recommending shaving the bobweights and balancing the crank with heavy metal to avoid having to grind the pistons for durability reasons but that sounds expensive. I understand Venolia pistons run about $65 each but that may be an old price. Even so, those could be made to fit. The stroked 300 is going to be pricey any way you look at it.

The deck on the 340 is roughly 1-3/16 taller than the 215, and there appears to be a coolant passage compatibility issue between the '64 and later blocks. Could be nothing more than having to use aluminum intake with aluminum heads and same for steel, could be more. At this point I don't know. But that height difference is enough to mess with the alignment of the headers, meaning I might have to either shave an angle on the ports or cut and reweld the header tubes. Well, they need re-coated anyway, that'll be as good of an excuse as I'll get.

Other than that, I think the steering will clear but I'll have to dig out the 300 heads and look at them. Another concern is the distance from the engine mounts to the bottom of the crank. With an extra inch in the stroke, that's 1/2" more below the centerline which has to be accounted for somewhere. And finally, since it's a 90* engine, each side of the intake is going to be an inch or more away from the intake, depending on the distance of the flange from the piston centerline. If the two heads have the same distance then it is the same as the difference in deck height or a little over 1-3/16" That's a pretty thick spacer. But so fa, that's the list.

Jim
Jim Blackwood

Jim-

When Dave's stroker was built, Dan used stock pistons from a Jeep, so that cost would not be excessive.

Dave M has sold the GT with the stroker.
Jim Stuart

Jim, your question got me interested in the differences between the 300-340 and the 350. I thought I remembered a major redesign and at least the heads were changed quite a bit as the intake exhaust pattern was changed. Here's a web site with some good information on Buick engines. http://www.taperformance.com/newpage1.htm
Bill Young

Bill, here's another good link:
http://www.roversd1.nl/sd1web/capacity3.html
http://www.roversd1.nl/sd1web/

The 350 has larger cam journals to prevent confusion, has adjacent ports like the SBC and .050" larger bores. It's a derivative of the 340 so about the same weight, about 450lbs with iron heads and intake. An aluminum intake is available from TA but no aluminum heads have ever been available. Using the '64 heads and spacers for my 215 intake on the 340 I can probably expect to save 60 to 75 lbs, bringing it in around 375-390 more or less. These two engines were maxed out in terms of stroke and if the rod bearings failed the rod would strike the cam, trashing the engine, but they were light and powerful. The block was a high nickel iron and the engine was essentially the same width as the Buick big blocks which had the shortest stroke of all big block engines, only .050" longer than the 340/350.

Wikopedia states that the Buick 455 was 150 lbs lighter than the Chevy 455. But this chart:
http://www.241computers.com/ford/ContentExpress20-30-38.html
shows 75# difference. However the 455 was the first "thin-wall" casting and may have been 75# lighter than the predecessors in that family, the 400 and 430 which are listed in the chart at the same weight. If that is correct, then the 455 Buick weighed only 525 lbs with iron heads and intake. just 75# more than the 350. Both aluminum heads and intake *are* available for it, saving 60# with the heads and maybe another 20 with the intake or getting down around 450 lbs. Although about the same width the engine is longer, but could still be made to fit in the MGB engine bay by moving the slam panel forward as I have done in my car. The steering might be an issue. This is only 120# or so heavier than the B series engine, a creating phenomenal possibility but comes with a steep price tag, $2500 for the finished heads and $1400 bare. Still, for someone with the money, that would be right up there with the most extreme MGB swaps ever done. Cooling could be a problem...

Jim
Jim Blackwood

Jim, I'm a bit confused. You talk of using the aluminum heads, but if the cam journal diameter is different where are you going to get a cam with the lobes in the proper sequence to match the heads and the 350 block? As you said the intake ports are side by side in pairs like a SBC, not seperated like the 215, 300, and 340.
Bill Young

The short answer is that you can't Bill. I'm planning on using the aluminum 300 heads on a 340, which has the same cam and port arrangement as the 215 and 300. If a 350cu.in. engine is desired though, the 340 can be bored out .050" and there you have it. Everything else is the same.

I put a post out on the big block buick forum to get some accurate info on size and weight just for the sake of curiosity. Provided it is compact enough, and small enough, I'm pretty sure there's going to be someone who would be willing to try this swap. Think of the bragging rights! At last, something to contest that hemi bugeye. (And we could finally at long last learn the true strength limitations of the MGB unibody!)

Jim
Jim Blackwood

455?! Waaay too much torque!
Carl Floyd

Ahhhh! the light comes on! Just got a little lost in all the numbers. Sounds like a torque monster with the blower, and your car flies now so I hear. ;-)
Here's some information on Buick engine weights and the link to the web site I found them on.
http://www.241computers.com/ford/ContentExpress20-30-38.html


Buick 1953 322 V8 635 (51) OHV V8
Buick 350 450
Buick 401 685 (1) ('59 Nail Head)
Buick 430-455 V8 600 (one ref showed 640) (10 - 600)
Buick 1963 odd-fire V6 414 (2)
Buick V6 375
Buick 3.0 V6 '85-up 350
Buick/Rover 215 V8 318 (and Olds)
Buick 1961 215 V8 324 (2)
Bill Young

Sorry about the duplication, I need to lear to read all the posting.
Bill Young

That's one of the sites I was looking at. Also on the BBB forum it was stated that the early 455 blocks were 50lbs lighter than the later one, so there's clearly some mis-information flying around. Still, I suspect anything under 500lbs would be feasible, as that would be 75-100lbs lighter than a SBC, or about equal with a SBC with aluminum heads and intake, and we've seen that one done several times.

I'm just guessing that the steering shaft might need to be relocated. The rods are longer than the 340 by .242" +.050" on the stroke so about 5/16 on the block but the bores are larger, meaning the side of the engine sticks out further and the heads would be a bit larger too. The extra deck height won't hurt as much as extra thickness and I think it might just be into the steering a little bit. But, we've also seen successful re-routing of the steering so there's no new ground being broken really.

Jim
Jim Blackwood

This thread was discussed between 27/01/2007 and 01/02/2007

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