twin 40's on a 1.2spi ?

[superfu-kingnova]

hi peeps , im driving a 1.2spi :( . but i got a genuine set of sport twin 40's and manifold and airbox . but i have been told they will not work well with my 1200 head , so can i just change my head to a 1300 or may be 1600 ? and leave the bottom half of the engine the same ? anyone done this before , please any advice , thanks . :cool:

[Adam]

Use a 1200(carb)/1300 head. Might need measure the compression ratio, as the 1200spi block is different to a 1200 carb one.

You'll also need a 1.4SR dizzy/coil setup.

And a adjustable fuel regulator to bring the fuel pressure down.

You would also be best with an aftermarket cam, as t40s alone do not offer big gains.

[Stuart]

and dont forget to have a GOOD rolling road setup...

[bigbened]

how quick would a 1.2 be on twin 40s and a cam as im hoping to do this too

[Adam]

Probably about 65-75bhp i'd say.
Not going to be amazingly quick for how much you've got to spend.

[SuperNova!]

40s are not needed on a 1200cc engine.

[Adam]

Lol

There not "needed" on any engine.
But one carb/venturi on one cylinder is obviously much better than one carb/venturil for 4cylinders on ANY size engine.

[bigbened]

lol well im just gonna go for a 32/34 carb if not how quick would that be compared to 40s

[Welsh Dan]

A lot better than your spi with the right head, cam and exhaust.

[superfu-kingnova]

thanks guys for all ya advice and info , :thumb: :cool:

[Adam]

A 32/34 weber is a good compromise between 40s and the std pierburg carb.

I'd keep SPI over a 32/34 anyday tho, but thats just me :D

[bigbened]

its a carb lol