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Weber setup - jetting advice
Shamrock GS - 25/7/08 at 10:25 AM

OK - now that that the original weber 40s are toast (see 'Car up in smoke - get an extinguisher' ) I am going to upgrade to 45s.

Any advice on jetting for the following

2l pinto, electronic ignition, BF30 burton road / rally cam, stage 2 unleaded head.

Also is it reasonable to use my inlet manifold for the 40s and ream out for the larger carbs or should I bite the bullet and buy a new inlet - if so how long? Possibilities range from 1.5 - 6 inches.

Then there is the trumpet length to consider - I am favouring a longer set to avoid the current fire hazard but dont know what difference that will make.

Cheers

Gary

[Edited on 25/7/08 by Shamrock GS]


pewe - 25/7/08 at 10:35 AM

See www.dellorto.co.uk as they do Webers as well. Give them a ring for advice - I've always found them more than helpful. Cheers, Pewe


Mr Whippy - 25/7/08 at 10:53 AM

I have a manifold that is suitable for 45's £30 plus postage

I also have a set of 40's, with trumpets and matching foam PX filters, all you need is the barrels and jets from the last set of 40's.


[Edited on 25/7/08 by Mr Whippy]


procomp - 25/7/08 at 02:03 PM

If you are still looking for a set of twin 45's as i was. I had no look finding any good s/h ones at a price that was cheaper than new.

If you want contact details for supply of new ones at a very good price just U2U me. Unless you are lucky enough to have a set already to go.

Cheers Matt


jamie1107 - 25/7/08 at 06:56 PM

you could stick with the 40 s and have some one spin up the choe tubes on a lathe this will cost less and keep power lower down he rev range all be it marginally less power its useable as a rough guide i would go 37-38 mm on the chokes f16 emulsion 145 mains 50-55 idels depending on your cam timing 40 pump jets and 180 air correctors 4.5 aux if you get rebuild kits then the needles come with them 120-122 should be fine
bear in mind emulsion tubes are alot of money then theres all the jets and rebuild kits much easier to go megasquirt 1 v3 with msns extra tagged on and run edis then you can use bike throttle bodies and sell your webers and manifolds on ebay for 300 covering the cost of the conversion or keep the webers sell all the jets and use them as throttle bodies with injectors in the manifold
third option go bike carbs gsxr 1000 or 750 carbs work a traet on pinto s and jets are pence
so many options lol


Shamrock GS - 26/7/08 at 10:06 AM

A scary amount of advice here - will try assembling a set of 40s first as easiest option.

Whats interesting is that now that the carbs are in bits it appears they were mismatched. Different choke and different main jets. Wonder what the car will be like with a proper setup?

Thanks for words of wisdom

Cheers

Gary


jamie1107 - 26/7/08 at 01:05 PM

if the chokes and mains are mis matched it will be impossible to ballance the carbs one pair of cylinders will almost be fighting the other pair
you can get away with miss matched emulsions as long as the idles and mains are different you can also drill out your mains and add more progression holes to the emulsions to avoid buying other tubes but thats when you get into specialist teritory
if you get stuck i have a box full of jets from when we used to fit webers now we just use megasquirt if someone wants carbs then we go for bike carbs i may have some of those to depending on what power your after
if you need any jets you pay the post and i will swap your jets for the size you want if i have then that is
im guessing your ok with the rebuilding and setting up of the carbs before you put them back on ?