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MG MGB GT V8 Factory Originals Technical - Engine rebuild

Hello All,

I am looking for a reputable shop to rebuild my 3.5L. I live in the Baltimore/Washington area and would prefer someone who has experience with the Rover V8 and can do the job in a timely manner.

Thanks in Advance,
Joe
Joseph Lagasse

Glen Towery isn't too far from you and he's one of the more respected names in V8 MG's. I think his shop is in Delaware if I recall correctly. I don't have his number close at hand, but I'm sure someone on this board will.
Doug DeLong

I just finished rebuilding a 3.5L V8 and I have to say, there's no rocket science involved in the project. Just take it apart, have a qualified machine shop do the machining work (tell them it's a 63 buick 215 and they'll have all the specs for that) and re-assemble it when they're done. Took me a couple days of dis-assembly and re-assembly and about a week at the machine shop, but hardly anything that wasn't manageable. As long as you're going to rebuild the motor why not make a few power modifications? (assuming you haven't already done so.) Higher compression pistons, a true roller timing chain, and a better camshaft are a great way to beef up the motor.

FWIW,
Justin
Justin

Joe,
If you have 6 months time to wait for and lots of money then go to Towery, otherwise you can easily do it yourself with the help of a buddy that knows somewhat of engines. Like Justin told you, it isn't all rocket scientific knowledge you need, just some common sense and a good manual.
Justin, how is your project coming? Sorry for the delay. I am home now.
Werner
werner Van Clapdurp

Werner,
Good to see that you made it back home safely. =) It's progressing, albeit at a bit of a snails pace right now. My motor (3.5L suped up V8) is back together and the hotwire injection has been modified (shortened) and installed on the motor. Next step is finish up gathering the clutch/transmission components and i'm ready to go in the car! With hope (and an incredible amount of luck) I'll have the motor in the car before June.

I'll keep you updated,
Justin
Justin

Doug,
Yes, Glen is fairly close by, but see my response to Werner. I feel much more comfortable with the gentleman from your state. I intend to order a few more parts from D&D.

Werner,
I had heard both good and bad about Glen. After calling ahead, I drove over to his shop, about 2 1/2 hours from me, to talk with him about his services and to take a drive in his latest conversion. When I arrived he was initially unavailable. I was then able to speak briefly with him while he rushed to complete a job that seemed late.
He was pleasant given his apparent hast and is extremely knowledgeable, but I think the old business phrase "the customer is always right" might be alien to him. I left not getting to hear his car run!

Justin,
Is there a specific engine rebuilding manual that you could recommend for the Rover V8? I'd like to have that even if I decide just to farm out the machining work.

Thanks for the responses!
Joseph Lagasse

I ordered a haynes manual for the range rover from rovers north. www.roversnorth.com I think it costs around $30.00 and has proven invaluable to me as I have maintained the fuel injection system off my rover V8. Then engine section is quite thorough and covers most variations of the motor.

The manual from any vehicle that carried that V8 would proove just as sufficient. The only major changes over the years were the methods of induction.

Hope this helps,
Justin

p.s. my local machine shop wants $500.00 just to reassemble a V8. I can think of 10 things I'd rather spend $500 on for a project that I, at 22 years old, am more then capable of doing. Food for thought....
Justin

Justin, Noticed with interest that you are adding a Hot wire plenum to your engine. Would be interested to know how much exactly you had to machine off what to make it fit. I am about to fit an 86 Range Rover motor to my B, this motor has the later style digital Hotwire plenum and the earlier style analoge electronics. The car's a rubber bumper if that makes a difference.
Peter

Peter, I just bought a full HotWire system from a Range (1991). I have a B GT V8 from 1973, so looks more or less rubber bumper with regard to crossmember and mounting of the V8 (quite low). Nick Smallwood has described in detail how much to take of and where. Else it is also in the book "how to give your mg v8 power".
Frank

I had 7 hundred thousandths (.700") machined from the bottom of the trumpet stack and in addition to a set of motor mounts from Glen Towery it should all fit under the hood without any problems. When you take the injection system apart you'll find it's basically in three pieces: the top plenum cover, the trumpet stack, and the manifold. After machining the trumpet stack you'll find that you need to machine the bottom of the air take offs on the trumpet stack so they don't interfere with the fuel rail, and you'll need to machine the top off the four brackets that actually hold the fuel rail to the manifold. I can probably take some pictures on my webcam if you need me to, but once you get it apart and actually get to look at it it's pretty straight forward. One other change I had to make: the coolant take off right beneath the air intake had to be machined a bit so it didn't rub against the valve cover. I'll do my best to explain it, but it wasn't hard. When you remove the plenum cover and turn it over, you'll see the take off with the two coolant hoses right beneath the air intake opening. Three of the four bolts holding it to the plenum are short and one is long, I had to machine down the platform that the long bolt threads into. Once again it's easy to see once you flip things over and take a look at it. If you have any questions or want to see pictures of what I've done, let me know and I'll do my best to facilitate your requests.

Hope this helps,
Justin
Justin

I guess Glen's mounts are really lower. .700 wouldn't clear the hood on my car (77 RB)

I removed 1.2 inches from mine to get an eighth to three sixteenths clearance.

I took .800 from the bottom of the trumpet stack housing. I stopped before I obliterated the pilot diameter for the trumpets (Which you can remove by heating in your oven to about 300F).

After I took this off, the fuel rails interfered with the bumps on the underside of the housing. I machined these off too.

I filled the bosses for the vacuum lines with a piece of 6061 aluminum rod (aircraftspruce.com) and welded them in. I relocated the brake booster line to the back of the top of the plenum. Standard metric pipe tap.

I took .400 from the top surface of the trumpet plenum, cutting through the plug I'd welded in.

I used this approach because I was reluctant to machine the flange on the top plenum because it was difficult to fixture and time consuming to machine such a narrow piece of aluminum. You can't take too much off of it anyway.

My machinist charge me one hour of shop time to do the job, but it didn't include the welding which I did.

One other thing to note- when you take the water system off of the bottom of the plenum, the holes go all the way through, so you need to plug them. I used set screws that I could drive flush to the surface.
Phil

Glenn's mounts will definitely have to be lower or your right, things won't fit. I should have said in the previous post that installing the engine in this manner won't come without some other drawbacks. For instance, I'll have to use a shorter gear shift housing because the motormounts push the transmission so far back. A small price to pay but a consideration none the less.

Justin
Justin

Frank, Justin & Phil, usefull information thank you.
I guess the extra inch of rubber bumper "ride hight" will work in my favour EFI wise.
I took Franks advise and obtained both Roger Williams books and was subsequently alarmed to read that 82 to 88 EFI comes under the heading of "leave it to the experts, too hard". However he does not say why. From memory the plenum looks much the same as the hot wire. Does anyone know what the difficulty might be?. I hasten to add that purchase of this engine hasn't been finalized yet but it seemed a good deal and was about to hand over handfuls of $$. Feeling cautious now.
Peter

I'm confused.

I thought that the mechanism for getting the engine lower is the mounts, not whether it is CB or RB. What prompts your comment, "I guess the extra inch of rubber bumper "ride hight" will work in my favour EFI wise"? I think that unless you buy Towery's mounts, you'll have to lower your EFI 1+ inches. Straighten me out, please.

On the EFI question - what is the system from 82-88? Is it the L-jetronic based system using the -4 ecu and the flapper type airflow meter? If it is, I can shed some light on the problem with that system.

Phil
Phil

Phil,

The rubber bumper crossmember has it's mounting brackets extended 1" higher than the chrome bumper cars (thus the increased ride height). This would allow the engine to be placed 1" lower between the frame rails without the sump interfering with the crossmember. I've seen a few cars that use Glenn's mounts and the engines are much lower and further back then you would typically expect. I also recall that one of those owners had to make a few "adjustments" with a 5lb hammer to the engine bay and tunnel to accomodate this location.

Joe
Joseph Lagasse

Phil,
Achording to Roger William's 2nd book jettronic systems were used on Range Rovers motors around '86 and it definity has a flapper type air flow meter, I think you're right.
I anxiously await your reply.

Joe, Justin
There is a company here called 'Dello Automotive' who make adaptor kits for Toyota SUPRA gearboxes which are small, tough and light weight (Rover bolt pattern T5's are hard to get in Australia & hence very expensive). Dello's also offer a range of stick positions 18,19, 20.5 & 21 inch (21 is the usual for MG's), so moving the motor futher back (& down) is all pluses.
Does anyone know how far back from the "standard" MGV8 engine position you can go?, that is, how much clearance between the heads and the footwells have you got in a factory V8. It would help when selecting the stick position, at the moment I'm thinking 20.5".
(also does anyone have Towery's phone number?, getting access to a phone book from this hemisphere is tricky)


Peter
Peter

I've driven a supra before -- what a slick car! That thing shifted so smooth it was like a hot knife through butter! Unfortulately, crashed supras aren't common place here. I just did a quick search of my two favorite junk yard websites for foreign cars, and neither had a supra sitting around.... If I had *another* 20,000 to drop on a third car, I'd be hard pressed to not get a mid 90's supra. Back on track here.... Glenn Towery: (302) 734-1243. I guess the best you can do is test fit the assembly once you choose some motor mounts and measure to see how long of a gear shift assembly you need.

Nothing resolves body rubbing problems like a BFH....

Justin
Justin

Peter & Justin, the Toyota "supra" gearbox is used in the rear wheel drive Toyota Celica as well. I believe some of the earlier boxes had ally casing & wouldn't be suitable for a V8, but the majority had cast iron cases. I've been using one for the last 12 years. The only difference between a Celica & a Supra g/box is probably the price, depending on how unscrupulous the vendor is.
Barrie E
Barrie Egerton

Justin,
Barries right about the Celica (as far as I know). The main attraction of the SUBRA for me was that Dello can deliver it as a complete package with warranty and choice of ratios stick positions etc. For the Supra there are 4 varieties W55, W57, W58 & W59. Main differences are in the First and fifth gear ratios. The W58 has 1st @ 3.28 and 5th @ 0.78, W57 3.28 & 0.86, W55 3.57 & 0.85 while W59 is less usfull at 3.95 & 0.85. I don't know what the various Celica ratios are but it would be usefull to know as they are cheaper and being 10kg heavier is not much of a tradeoff to make. Can you shed any light Barrie?

The W58 seems the best choice for those who don't want to spend $$$$ on their diff's (me) but of course they are the hardest to find.

Phil, still anxiously awaiting your EFI L-jetronic expertise. I got hold of a Range Rover manual and as far is I can see the fuel rail might be the problem. The injectors are held in pairs to the manifold with retaining plates and conected to the fuel rail by short lengths of rubber hose so the fuel rail seems to site higher (by about one shortrubberhose lenght)than the Hot wire. Does anyone know if it is a possibility to shorten or bend the rubber hoses on the top of the L-jetronic injectors sufficiently to displace the fuel rails down or to the side?. It would make fitting the plenum under the bonnet dead easy if the latter is true. Or is it possible to substitute a Hot wire fuel rail and injectors?. I would like to stay with the L-jetronic if I can because of cost (zero, it comes with the motor) and I like being able to play around with the fuel mixture.

Peter

Iíve been hesitant to reply to you post because Iím not sure my experience is relative to your decision.

My experience is with the flapper L-jetronic system used on the Rover SD-1. It is the system shown on the cover of Rogerís book.

In looking in my Haynes Manual for the year Rover engine you have, the system looks like it operates in a similar manner. The inlet manifold looks like the inlet from the SD1 as do the rails and injectors, but the plenum housing looks like the hotwireís, except that the cold start injector is used.

Iíll give you the experience Iíve had. You can draw parallels to your dilemma.

-The injectors are expensive and difficult to source (at least in the states) at $45 rebuilt and $110 new for Bosch units. RPI Engineering says the set should be replaced, and Iím inclined to agree. Three of the eight failed on my car and were the source of drivability problems. I understand there are also Lucas injectors that will work.

-The airflow meter uses a wiper on a resistor printed onto a circuit board, and when it wears, it can send erratic signals to the ECU. You can shift the board slightly and expose the wiper to a different part of the resistance track, but itís only a temporary fix. The cheapest airflow meter I could find was about $300. Cleaning the track with a pencil eraser and the wiper with some 1000 grit paper will help too.

-The box I had was the Ė4 Lucas and thermal cycling of the box eventually led to cold joints. I had to take it apart and re-solder the key connections. Even when everything is working right, there is sometimes a surging sensation at steady state speeds (this may be a function of the Lambda circuit, which I donít know if you have down there)

-There is no fault code readout. You have to deduce the problem and then substitute the suspect component. Problem is, there are so few of them here in the states that it is difficult to troubleshoot. Most everything is Bosch, which is not a problem, but the ECU and the AFM are Lucas and hard to find.

-The system is old. I took mine off of a car with 45K miles and I thought it would still be pretty good. I ended up replacing many of the connectors and some of the wiring.

-The injectors connect to the fuel rail with flexible fuel line. There are no less than 22 connections to be made with hose clamps, and this is just a disaster waiting to happen, with leaks and the potential for fire. The injectors and fuel rail sit up relatively high on the manifold, and when you lower it, there is a load put on the connector, hose connections and rail at the 3 and 5 cylinder. I tried to replace the hose about once per year and use the special fuel injection type clamps (not the worm drive)

-The combination relay is a specialized item instead of an off the shelf part, and the connector to it is somewhat fussy. Mine failed and was $65 instead of $6. It is common to some BMWs, so I bought it at a BMW mechanics shop.

The system is about three generations behind, but if youíre set on using it, I wouldnít know why you couldnít. Unless the unit canít be modified to clear the sheet metal or the harness is part of the car instead of a separate piece, I donít know why you couldnít. If you find out the source of Rogerís comments let me know.

If you want adjustability, Iíd suggest you spring for one of those excellent Australian Haltech ECUs with the flying lead harness that can be programmed with a laptop. Better yet, get the plenum, manifold, injectors, rail and regulator off of a hotwire car and use the Haltech ECU. It changes the system to a speed-density and eliminates the need for an airflow meter altogether.

Good luck,

Phil
Phil

Phil,
Many thanks , from what you say the L jetronic (in the long run) is likely to cost more than the Hot wire and be a whole lot of trouble. I will look into the Haltech idea, I know where I can get a short re-sleeved 3.5 (to 3.9)pretty cheaply.
Question- does re-sleeving 3.5's up to 3.9's cause problems you know off?
Peter

This thread was discussed between 07/04/2002 and 19/04/2002

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