twin 40s to 1.6 gte

[briscoe2004]

what is need to fit them to my gte?

i have twin weber 40's on 1.2 manifold.

help is appreciated.

do i need a new pump or anything ignition? etc.

[NovaloadedAgain]

You will need another Manifold as the cathedral port manifold you have now will need to be replaced for a square port manifold.

The fuel pump could do with replacing but is not necessary my mate runs his gte with an original & I run mine with a mechanical fuel pump. Although it is best to get a 5 psi fuel pump. Dont quote me on that, My friend told me about it along time ago.

[dunova]

You will need another Manifold as the cathedral port manifold you have now will need to be replaced for a square port manifold.

The GTE/GSi/SRi all have ROUND ports, so you'll need a t40 round port manifold. Also, 5 psi is not ideal. Really you want 3.5-4.0 psi, so get yourself a fuel pressure regulator and i would also advise a facet or equivalent fuel pump.

You'll also need a set of trumpets and an alternator lowering bracket. And tbh you won't really see great gains with just twin 40's. To get the most out of them you really need a lairy cam and headwork.

[briscoe2004]

i have put a kent fast road cam and vernier pulley on, have a stainless exhaust from the manifold back what bhp gains will i roughly get 10-15 or more?

[Nick]

yep as dunova says.

you will need a Round port manifold (to suit SRi/gte/Gsi heads), they usuaklly come new with an alternator bracket.

Then you'l need the carbs, rejetting for a 1.6.

You'l need a Fuel pressure regulator.

You can run a Mech Fuel pump with no problems.

then make sure you have all the linkages e.t.c !

nick

[getlost29]

id just stick with the fuel pump u got now and get a regulator, so if u can port the head and get more air flow u got the posibilty of upping the pressure with a regulator, chose ur trumpits wisely as they will affect ur peformance, shorter tumpets woud be the best , but it depends what u do with ur car

[Snowface]

webers need 3psi to run best and dellorto's 3.5psi.

if you port your head, bigger valves etc, upping the pressure will do nothing benificial. You may need to get it re-jetted/setup thats all.

[dunova]

This is why i said to upgrade your fuel pump;


if u keep the gte pump make sure u get a 3 port regulator with return

these have fuel in, fuel out to carb, fuel return to tank

the injection pump will continually be hitting lockout otherwise as the fuel its pumping will have no where to go

[Aragorn]

unlike injection engines upping the fuel pressure on a carbed engine will just bend the needle valves and flood the float chambers causeing the engine to run totally shite

only purpose of the fuel pressure on carbs is to keep the floats full - if u need more fuel entering the engine u need to change jets

[robb]

Doesn't the GTE head have an extra port in between the middle inlets for some sort of sensor?

Just I noticed something when I had loads of earthing problems on inj system so went to a carb to get it running for the woods.

[Aragorn]

egr valve - u will need to get a plug made up for the hole in the head as the 40's manifold wont cover it

[Snowface]

is it in the head or the cam-carrier?

[nathan.]

its in between inlet ports 2 and 3. I threaded the hole and fitted a bolt with a copper washer.

[briscoe2004]

what bhp figures 'roughly' will i be achieving with, kent fast road cam, vernier pulley, twin webber 40's, gas flowed head, just a rough guess

[nathan.]

with a decent set up, you should acheive more than 130bhp at flywheel. mines 127bhp at fly but my chokes are too small,