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twin carbs
Stuart_B - 24/2/11 at 08:07 PM

hi all, just wondering what type of carbs would be good for a 2.1 pinto with a big valved head, and a revy bottom end?

as well what sort of money would be a the carbs be?

i am right of thinking that twin 45 would be good?

and what is a good price?

cheers

stuart


macc man - 24/2/11 at 08:13 PM

Many people are now using bike carbs such as zx9r kawasaki , Mainly due to cost and reliability. All you need is a suitable manifold. See other threads on here.


Stuart_B - 24/2/11 at 08:24 PM

i got bike carbs on my 1.6, but so people love the old school way, and seem to dislike bike carbs,

would there be any performance difference between twin carbs and bike carbs, if i could give prof, i reckon i could convert him.

cheers

stu


mookaloid - 24/2/11 at 08:30 PM

Twin 45's are the classic way forward but a good big set of bike carbs would also be ok.

Ideally throttle bodies are the way to go - jenvey or home made bike TB's should work too.


jacko - 24/2/11 at 08:59 PM

Bike carbs for me every time
Webbers are BIG fuel pumps pumping fuel all the time
Bike carbs only use the fuel the engine needs [ just like SU carbs ]
set the carbs up and then forget them
webbers tune up every few weeks

and yes i have used both over the years racing etc
Jacko


r1_pete - 24/2/11 at 09:26 PM

Webers are expensive to set up, and due to the fixed venturi they only really come into their own at wide open throttle. I had triple 45s on my E Type, which I've removed and fitted Twin SUs, will be going GSXR750 Throttle bodies, with the SUs the car is much more drivable.

I did Bike carbs on my last project, on a Zetec, very happy, and easy to self tune once the jetting is correct.

The variable venturi of most bike carbs maintains high inlet gas speeds, which improves atomisation, torque and economy.


mcerd1 - 24/2/11 at 09:35 PM

^^ what they said

Twin 45's would be right for a road car or maybe twin 48's for a full on race engine (thats going to spend it whole life at or near its rev limit)

ZX9R and R1 carbs are both equivelent to twin 45's in tearms of the max power they can produce (both are around 39-40mm chokes)

I think fireblade carbs are around the twin 48 size (42mm choke I think)

[Edited on 24/2/2011 by mcerd1]


Oddified - 25/2/11 at 12:01 PM

45's/48's are both fine, and will run perfectly if set-up properly (fuel economy & performance) but there's not that many people/rolling roads who really really do know what they're doing with them...and getting less all the time now there's less people using them.

Bike carbs are easier to get respectable results.

Ian


Stuart_B - 25/2/11 at 05:37 PM

cheers for the replys guys

will look at alu inlet manifold for bike carbs.

cheers

stuart


mcerd1 - 25/2/11 at 06:49 PM

quote:
Originally posted by Stuart_B
will look at alu inlet manifold for bike carbs.


bogg bros. ones are very nice

here's mine ZX9R carbs on an alloy manifold to suit an EFI pinto head (all supplied by bogg bros)


not cheap mind, but still allot cheaper than a pair of new webbers



[Edited on 25/2/2011 by mcerd1]


Stuart_B - 25/2/11 at 07:14 PM

they look so nice


ssc28 - 25/2/11 at 09:02 PM

There's some one on here doing inlet manifolds for bike carbs or TB's perhaps not quite a athtetically pleasing as Bogg Bros but also about 1/3rd of the price.
Having said that a pair of 45 webers or dellortos always sounds better, and uses more fuel.