Hi I havent even started building my kit yet but have just sent my engine away to be reconed. The question is do i use 40 or 45 carbs when i put it back together, it will be running a fast road cam and flowed head in MK Indy or similar.

iirc twin 40's are good for about 140 / 150bhp. Anything more and you will need twin 45's.

Im using 38dgas for up to 130bhp.


If you are aiming for 140ish with 2.0litre and stage 2 (?) head but fancy a rebuild to 2.1 in the future i guess i would go for twin45's as you wont need to replace them in the future.

Ive seen a few std pintos running twin 40's no problem. A lot of people are a bit optimistic with their targets and claims, i know iam being adventurous with my 130bhp target, probably will be more like 115 - 120 (at the flywheel).

Welcome to the Mad house by the way. Just noticed this is your first post.

Nice to see you are going Pinto route. i believe there is a lot of life left in the old lump yet. Do some searches, Dave Walker wrote an intersting reply a while ago.

http://www.locostbuilders.co.uk/viewthread.php?tid=23342

Des Hammill book is well worth a read.


Prepare yourself for some flak from the BEC boys. They have this strange idea that bike engines are good for cars. Yes they are quick but noisy and too revvy. Ive been trying to pursuade them that bike engines are for puffs but seem to have gone unheard for some reason!! LOL

welcome M8te
Give Macspeedy a u2u he has a pinto running webers......

45's - will be more flexible in the long run.

That's what I'm using.

Pat...

I am running a pinto with 45's.

recently dynoed at 149 bhp at the wheels.

Gas flowed head, fast road cam and some skimming / flywheel lightening etc.

Go for the 45's - you can do anything with the 45's that you can do with the 40's but not the other way around (it's all in the choke sizes)

I believe R1 bike carbs may be an even better option........

Good luck and if you have any more pinto questions feel free to u2u me

Cheers

Mark

45's definately-40's cant supply enough air for a mildly tuned pinto-they will work but run out of steam.

Have a look at the carburation section of this excellent guide written by Puma:

http://www.pumaracing.co.uk/pinto.htm

HTH,
James

BIKE CARBS , much more 'Locost' , no flat spots good flexibility ,good top end......
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I have a Vulcan tuned 2.1 in a dutton pushing out 175+ bhp. i have twin 45 dellortos. this engine rocks

Dave I love the carbs what are they off of and how did you sort out the manifolds

Dave I love the carbs what are they off of and how did you sort out the manifolds

They are 38mm Mikuni's off a Suzuki GSXR750WN, they mount nearly level which means you dont have them sticking out of the bonnet.

I made the manifold out of mild steel plate and tubing , and mig'd it up.......
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