V8 into MGB Won't Go?

The 1UZFE EGR Delete Kit is available for sale here.

V8er

New Member
I am very keen to establish the practicality of upgrading an MGB with a non-turbo 4000cc Lexus V8. Can anyone advise generally please, starting with whether this has been successfully accomplished & -

1 - What donor cars do suitable carb'd & efi engines come from - (a)in the USA & (b) in the UK?
2 - Are any of these available with a manual/5-speed box/trans or if not what options do I have?
3 - The engine looks pretty wide at the top end – 31" across the manifold/headers I think. Will it fit in an MGB?
4 - The front of the sump ideally needs to be minimised to clear the MGB's front crossmember. Therefore the oil-pick-up-point needs to be mid/rear engine. Is this the case with any/all versions of the engine?
5 - The exhaust headers/manifolds will have to go out though the inner wings/fenders - does this sound feasible?
6 - I'm worried that the ECU controls the auto-boxed variants & if the gearbox/trans is switched to manual that the ECU will not "see" the box & will consequently not function! Is it possible that someone makes a supplementary harness (or maybe just an especially connected socket) that fools the ECU into thinking it is still controlling the gearbox?
Info gratefully received at

[email protected]

 
V8er,

This is a big ask.

Fitting a Rover V8 into an MGB is tight. This engine is around 150mm wider than the Rover.

Many years ago I fitted an RX7 engine to a B. Had reasonable room but the transmission tunnel is very tight. I recently replaced a rover V8 with the 1UZ-FE and it was real hard.

To answer your questions.

1. Any donor car will be EFI and Automatic. You would find a vehicle in the UK but I have no idea of price. As silly as it sounds I would look at importing a Crown half cut from NZ. They are very cheap over there and they have the right ECU set up for what you propose. If you put up a post on this Site some one should be able to help with advice on where to source a half cut.

2. All are autos. You can buy adaptors in Australia from Dellow and Castlemeaine Rod Shop (do a search under these names) which will allow you to fit a range of gearboxes. The gearbox of choice is any from a Toyota Supra. At the moment when swapping to manual there are a few ECU problems but buying a Crown solves these. Read up on the transmission/driveline section as KDog and Sideshow look like they are solving all the problems for everyone.

3. Yes the engine is very wide. I don't have the dimensions of an MGB but I do know the Rover 3500 is a tight fit. I will talk to a friend with a Rover V8 and see what room there is left.

4. The engine comes with 3 different sum setups. I don't have measurements for the mid sump but the very front of a rear sump extends 330mm from the rear of the engine. It is 390mm wide at the bottom of the sump but tapers to around 250mm at the bottom of the crankcase. If you need dimensions on the Mid Sump post a request. Some one else will have them. Mid mount sumps come on Crowns. Front and rear sumps are harder to get.

5. Yes this is feasible. I have seen it done on Australian race MGB's. You need to re-inforce the opening or the inner wings will crack. I would suggest (min) 3mm plate mig welded around the opening. Do not have any sharp corners as this is where stress crack will propogate from. Try and make the hole a circle or oval shape.

6. See point 2 about the lack of trans and the ECU. All I can suggest is search as much as you can because most of what you need is hiding in the Site somewhere.

There is no other Site on the Web with as much information on this type of swap as the Site.

I'll get back to you on the clearance in the B engine bay.

Don't forget the factory V8 had torsion bar front suspension instead of coil springs due to room problems. You may need to look real hard at the space available.
 
As far as I know this conversion has been done before.
Don't hold me too it as I never saw any photos, but I know some people were attempting it.

You're best option (in my opinion) is to get any model motor, source a rear sump, get an aftermarket ecu, get a bellhousing from either Dellow or Castlemaine Rod Shop as stated above, get a clutch and flywheel from them too (don't get a hulix clutch though, get one with at least 1800lbs pressure), get a Supra 5spd, and install it.

Is you MGB current positive earth as many were from the factory? If so, all your gauges and lighting will need to be modified and converted to positive earth.
 
V8er,

I spoke with a few people and the most knowledgable (Nepean Classic Cars of Sydney) MG specialist didn't think it would fit.

When fitting Rover V8s into them they need to modify the firewall, transmission tunnel, inner skirts plus fit a "soft nosed" steering rack to clear the sump. They also shorten the Rover engine by machining the harmonic balance and modding the water pump to make it fit.

I think you need to locate a car to get a lot of measurements. Alternatively if you can locate a panel beater (body repairer) they may have a specifications sheet for body re-alignment.

Just picturing it in my minds eye I can't see it fitting without lots of grief.
 
Hi Guys - Many thanks for the info, comments & suggestions. Sounds as if my Lexus concerns were justified. I've done a few MGB Rover/Buick conversions & was looking for something more or less as light but more interesting! Think I better search for someone whose tried getting the Lexus to fit before spending too much money. Anyone out there know anyone who tried - even if they failed or haven't finished?
 
V8er,

PM Peewee he may be able to direct you toward someone who has done this as he thought it had been done.

Try searching MG Clubs in Australia also all the Toyota Sites you can find.

Just search each Site for 1UZ or 1UZ-FE.

As a general comment on size I relpaced my Rover 3.9 in my Range Rover DAKAR with the Lexus and the new engine is at least 75mm wider each side than the Rover. It is also longer and taller. But heaps better
 
Lots of interesting engine transplants but interestingly nothing on Lexus engines. Is that telling me something? V8er
 
Yep, have compared measurments - some firewall changes are expected but length looks ok - its the width that bothers me. The Lexus will fit between the bonnet extremities but I have no way of knowing whether it is so wide across the heads that it will sit on top of the MGB's inner-wings. Hence my questions about exhaust exits.
No info from Dellow yet - although I am sure it will be forthcoming in due course.
Thanks for your interest, thoughts & contribution- V8er
 
V8er said:
Yep, have compared measurments - some firewall changes are expected but length looks ok - its the width that bothers me. The Lexus will fit between the bonnet extremities but I have no way of knowing whether it is so wide across the heads that it will sit on top of the MGB's inner-wings. Hence my questions about exhaust exits.
No info from Dellow yet - although I am sure it will be forthcoming in due course.
Thanks for your interest, thoughts & contribution- V8er
Unfortunately, if you're at that stage (measuring bonnet extremities), I'd hold grave fears for that project.

Whilst the engine is pretty-much the ideal engine conversion prospect, I believe that, if you REALLY want a V8-powered MGB, you "may" be better off going for a larger capacity push-rod V8 *shudders*.

It's worth noting that some of the large capacity V8s are, indeed, physically smaller than the DOHC per-bank V8s...
Probably not what you want to hear but, from personal experience, these engines (*UZ-FE) need a lot of room; something the MG-series cars don't have...
 
the 1UZ is about 700mm wide across the top.
stick that in your tape measure and measure it....LOL.

what about the 5MVE? the 3.4L mini-hemi V8 from the century's?
 
yeah that's it.
i get mixed up coz i know you can use 5M pistons in them if you're looking for forgies ...or whatever...
 
Not sure how you went with this research. I am planning to do this exact conversion - 1uzfe+supra 5spd into MGB. Had a look at one on the weekend in melbourne - Fits in with bonnet closed - some cutting of firewall but true with any older model 'B'. Sorry if adding to an out of date post - thought it might still be relevant as some times these projects take time (i'm sure you've all been there)
 
Motor was out when I had a look which was good for me - I took some pics of firewall and inner wing mods, engine mounts (hilux) and crossmember dressing. Owner guarantees that it fits - ithe 1uzfe is a pretty compact unit. One thing that made a difference was the sump - crown version sump fits in behind the crossmember, soarer version sump too far forward (i think). I think I read in this forum somewhere the motor came out with three sump locations (basically rear, mid and front) Not sure which is which - obviously I will check this before shelling out for my baby's new heart. Will hassle for pics when motor goes in again.
Your awdmoke project sounds like a beauty. Magazines and advertising seem to indicate a pretty dense population of rodders/kit builders/modifiers in WA so good for you. - do you have a webpage about it?
 


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