MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - MGBGT

I have just acquired a UK imported 1977 GT which has had a full body, engine, transmission rebuild to a very high standard
but needs re-assembling. I intend carrying out a Rover V8/Supra transplant and doing the chrome bumper conversion.
All the suspension has been rebuilt albeit to the rubber bumper specs and I now want to reduce the ride height to match chrome bumper specs (1.5" lower).
Could someone please give me their thoughts on re-sizing/setting the front and rear springs and the resultant effects on handling etc. A Ron Hopkinson handling kit (rear) came with the car - can this be used with the revised spring settings?
I have fitted telescopics to the rear suspension of my 2.1 litre roadster and have been very impressed - is this conversion advised for the GT also?
Peter M (Vic. Aus.)
Peter M

Peter,

Making the V8 and chrome bumper conversions will both alter the total weight and the weight distribution.
The Rover V8 and the Supra V8 are also different weights.

You will need to know the final wheel weight and have some idea as to what you want the car to be used for before you can start on the issue about spring / damper and anti roll bar rates.

So pick a plan and work out where you want to end up. After that you can see what you already have ; what you still need and what steps need to be undertaken in what sequence to get an acceptable result.

Cheers , Pete.
Peter Thomas

Peter,

the front crossmember of a RB car is better left in place if a Rover engine should be fit. Otherwise there will be problems with the clearance of the sump and the pulley.

At the rear lowering blocks can be used without a problem, a lowering set for the rear is offered by the MGOC and other dealers, at the front, there are different lowering springs on offer. Compare spring rates and lengths carefully when the conversion is done and order then! Using lower springs at the front, the axle has to be re-ajusted to prevent rapid tyre wear.

Ralph
Ralph

Peter M,

Here's a link which shows the rear springs I used on my '77 V8 roadster to reduce the ride height:

http://www.britishv8.org/MG/SimonAustin.htm

These springs are manufactured with "reverse-loop" ends to get the height down. On the front, I used the 550 lbs. springs. Stock RB cross-member as well.

I haven't experienced and premature tire wear but the car only has 4000 miles on it.

I tried the lowering blocks in an early attempt to reduce height but wasn't happy with the look nor did they lower much.

HTH
Simon
Simon Austin

Many thanks for responses to date. I should have mentioned that the Supra component is a gear box - not a V8 engine. I carried out a similar conversion on a RB roadster some years ago and resorted to shorter/stiffer front springs and re-set rear springs. Was wondering if any advances in technology have come about during the past four or five years.
Peter M
Peter M

Hi Peter,

One or two thoughts that might help you. I don’t think you should worry too much about the weight changes or distribution of weight. The Rover engine itself weighs a little less than the original MGB engine; however, it has greater water & oil capacity and its ancillaries probably weigh a little more. Your Supra gearbox definitely weighs less than the MGB original – but that doesn’t seem to be difficult! The overall weight and its distribution after your conversion will not be very different to that as originally built.

Regarding lowering the car, I used a lowering kit from the MGBhive & fitted it to my 1978 MGBGT. I have found that the car is really a little too low – I scrape my front spoiler on speed-humps sometimes – and I’m not very keen on the Spax telescopic dampers.

I would suggest that choosing springs and dampers on the basis of specification might not be the way forward. I’d be inclined to try the car with what you’ve got and see whether you like it. Maybe the parabolic single-leaf springs from the MGOC might be the way forward. I’m sure Roger Parker at the MGOC could suggest a good matching of front and rear springs and also how to achieve the height you want. Roger will always respond to a request for advice. I’ve found him very helpful.

Regards

Peter
P L Hills

Hi,

There has been a recent thread on the MGOC BBS regarding parabloic springs on a V8. The springs had bent into an S shape after a few thousand miles. It was a fairly standard V8 but the manufacturers conclusion was that the spring weren't designed to deal with the power. Have a look at the last two pics on http://www.jimmcglynn.pwp.blueyonder.co.uk/parab/index.html for pics of the problem.

Iain
I D Cameron

You have probably already discovered the V-8 conversion board on this site, also take a look at the British V-8 site linked above (very astute info) and perhaps dip your toe into the V-8 board over on the MGBExperience BBS, http://www.mgexperience.net/phorum/list.php?40 These folks have been there, done that, and, on the British V-8 board is probably the most organized and has many articles by some of the best V-8/V-6 conversion folks on the internet ~ many of whom also post on this and the MGBE sites as well.
Bob Muenchausen


Peter,
As you carry out the conversion, please take lots of photos! We'd be very grateful to know more about your car and the project of converting it. I have a particular interest in collecting and publishing anything I can get about the installation of the Supra gearbox.
Cheers,
Curtis

(current editor of The British V8 Newsletter)
contact info here: http://www.britishv8.org/British-V8-Contact-Info.htm
Curtis

Many thanks to all respondents. Will keep you up to date with progress and take photos.
Peter M
Peter M

Peter If you have a look at Hans Pedersons sight (High performance products) look under suspenson, you will find his great new front end mod. which replaces the front shocker with a wishbone and coil over which is fulley adjustable in ride hight, and he is in Melbourne.
DENIS H

This thread was discussed between 24/04/2007 and 29/04/2007

MG MGB Technical index

This thread is from the archives. Join the live MG MGB Technical BBS now