what do i need list please!!

Right i have a mk1 gti, i am going to run twin 40's or 45's or 48's..

Which are best!!!

List so far

Manifold
Twin carbs
New gaskets
Fuel regulator

I am doing it so it tidys up the engine bay also, i dont like have the pipes and cables from the injection system of the gti, going to get changed to a s3 anyway but this is for the mean time,



Any one selling a set up for the mk 1 gti?
Also what do i do about the injectors in the head do they need blocking up or run a different head etc if so which one cheers steve

Think youll need to dump gti fuel pump for something with much lower pressure even with the regulator.

abfmk1 said

Think youll need to dump gti fuel pump for something with much lower pressure even with the regulator.

Why?

thats the whole point of a regulator is it not?

Because the gti pump runs at about 5 bar, what do carbs need 5 psi?. dont think the regulator can cope with that difference but i may be wrong.

abfmk1 said

Because the gti pump runs at about 5 bar, what do carbs need 5 psi?. dont think the regulator can cope with that difference but i may be wrong.

The GTI pump will happily 'pump' at 0.1 psi if you want it to. The pump pumps, the pressure it pumps at isn't set by the pump itself but by the restriction upstream. Basically, a restriction occurs and it can keep pumping at higher and higher pressures (in fact, I've seen K-Jet fuel pumps pumping at around 8 bar) but this doesn't mean it can't pump at low pressures - quite the opposite.

In fact, from the pump's point of view, it will be like its on its holidays, pumping 5psi or whatever you need for carbs.

ob a standard 1.6/1.8 8v engine? i really wouldn't bother

wooders said

ob a standard 1.6/1.8 8v engine? i really wouldn't bother

Yeah. Speak to grungeisdead about it…..

mate i am not looking for performance i have a s3 engine sitting ready to go in but i am restoring first but so i can move it about was going to run carbs.. so thats the only reason

does it not run on the injection now? seems alot of expense and hassle just to be able to move the car about. it's not a negative comment, just a true one. by all means, fill your boots though.

always though twin carbs were overated why would you fit them to a non cross flow head ??

surely the heat from the exhasut isnt going to help


get the s3 lump in there job done

yeh and run it on carbs

Easy:

112 bhp + 28 internet horsepower = 140 bhp engine

that runs lumpy as hell and smells like a petrol station

do they really produce that much bhp??

My original 1.6 GTI was fitted with twin 45's first it was a pig, too bigger choke size I was advised by a guy who races 911's. I fitted 40's and found an immediate improvement, more torquey in the mid range, better fuel consumption (if there is such a thing with carbs) and a more drivable engine.

Carbs have their downsides, frequent visits for tuning, even more frequent visits to the petrol station, but great noise and they look the bollocks!!!


BTW the engine had been fully rebuilt (lightened and balanced) with fancy cams, head and matched / ported inlet manifold. Along with a custom exhaust it made 138 horses, until some numpty pulled straight out in front of me, when i was crusing at 40!!!!

Great car, expensive to do the work, probable cheaper to fit throttle bodies with a custom ecu (hear great things about megasquirt) more reliable, economical etc etc.

Tim.

just want to do wont be buying brand new, justs that i will collect.. back to the list please

steven_c said

just want to do wont be buying brand new, justs that i will collect.. back to the list please

In fairness, there's been some reasonable questions asked:

- Why won't it run on fuel injection?
- Why would you fit them to a non cross flow head?
- What about heatsoak from the exhaust?

i also have a 4 branch manifold fitted,  so the exhaust is no problem

The injection system will work but i dont like it, so its going,

Why would you fit them to a non cross flow head?   (what do you mean by this change the head to a carb'd head.. ?

the standard manifold has better heat insulation properties than a 4 branch. by cross flow, they mean having the inlet and exhaust ports on either side of the head and not both on the same side.

if you like carbs then only carbs will do! youre better off going for a set of twin 40's for your 1.8 8v engine im running weber twin 45's on my valver and still playing with different sized jets to get to get it right. i only sold my twin 40 dellorto's last month you could have had them off me! i think a standard gti on twin carbs would be well smart! they do make your engine mega thirsty tho mines at about 12mpg. sweet noise tho! getting cold air to them could be a problem tho id run some sort of a cold air feed to them if i were you and heat wrap the exhaust manifold