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MG MGB GT V8 Factory Originals Technical - Quad SU's on V8's

The book: "How to Build and Power Tune SU carbrettors"
by Des Hammill mentions a quad SU set up for V8 engines
which prompts me to ask is anyone running such a set up on any V8, Rover based or other?

I have seen a quad Weber sut up on a V8 Daimler 2.5 ltr using cross ram manifolds and very long induction tracts but none using the SU.

Cheers, Pete.
Peter Thomas


I once was with Dave of V8 Cconversion compagny in the UK to pick up some parts for my V8 and at that time there was a customer who had a V8 with Quad Su's. Dave kenw this customer pretty good so he should have more experience with this set-up. I have seen leaflets from i believe RPI engineering in the UK.
Good luck.
Peter van de Velde

Thank you for the information posted above.
From what I understand the four SU arrangement properly sorted is an excellent way to go.
I will do some more searching.
Cheers, Pete
Peter Thomas

It won't fit under your bonnet, however. I looked at other ways for the current original induction setup, and the 4xSU also crossed my mind. RPI informed me that the boxer manifold, as it is called, is no longer available. Burlen (SU producer) told me the same.
The quad Dellorto/Weber setup is very nice, but quite exotic and hard to get in good tune. But it is said that it remains in tune for a long time.
Personnally I have choosen to use EFI. The Hotwire system I bought from a scrapyard is currently at a workshop that skims the various parts. EFI is cheaper than for example a Weber 500 or Holley 390 setup and should be more economical to run as well for a 3.5.

Frank de Groot

The Webber set up must be ultimate for looks, if after performance go EFI or easy life 4b.



Yep have to agree with that having seen a few Italian V12's with masses of Webers they are certainly impressive.

I must admit to a distinct liking for SU's which are in my opinion a much under rated carb and properly set up usually as good as anything else for day to day running.

Now...should I begin training my right calf muscles in preparation to pushing against all those springs?
Where did I put that workout video tape?
Up 'n' down, back 'n' forward,,,move that tush!
Peter Thomas

I have a 1980 EFI- SD1(California)3.5 5-speed, that is legal but, not registerable, (long story). I also have a box full of Weber 40-DHOC carbs. I got in a trade. I am very interested in using the Webers with the 3.5 Rover engine. Any info. on this is very welcomed. Marc
Marc Judson

J.E. Developments once made swan neck manifolds for sidedraughts from cast alloy. Mangoletsi did this for downdraughts. Maybe Real Steel can help you to a set of suitable manifolds. The quad weber setup was also used on some Triumph TR8 works rally cars.

Frank de Groot

This thread was discussed between 07/06/2002 and 18/06/2002

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