throttle bodies on the cheap

Level 7 User Joined: 27 Feb 2004 Posts: 243

u either run TB's without a ISCV, in which case u hav the throttle butterflies open slightly, so u get an idle speed. or, u have one ISCV, which bleeds air into the TB's jsut after the throttle plate. i no the hill power, webber and others use the ISCV system. doubt theyd use it if it didnt work any good?

jimbo

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

all throttle plates are open slighty and they also have a bypass passage (the screw banked off on top of the stock TB).

Can't be bothered getting details the now.

Forum Moderator Joined: 16 Feb 2004 Posts: 1356

Hmm we've got a welder on the way so the temptation of Throttle Bodies is growing by the day!

Gay Rights Activist Joined: 07 Apr 2004 Posts: 1268

how will u plumb in the MAP sensor? dont forget on the standard engine its measuring pressure change accross all four chambers.
u'd be better off buying a fully reprogrammable ECU/sensors to do the job properly. that way u can just run a throttle pot (better than MAP sensor--faster reacting), and it can be fuelled and timed spot on

Forum Moderator Joined: 16 Feb 2004 Posts: 1356

Welcome stan, glad you could join us!

Gay Rights Activist Joined: 07 Apr 2004 Posts: 1268

why thank u!

Forum Moderator Joined: 16 Feb 2004 Posts: 1356

You've got to remember that our boy Jimbo here is doing things on a budget due to being a student....

Mr Quoter-vator Joined: 16 Feb 2004 Posts: 7405

and we like making things too...much more fun than just buyin things lol....

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

Well theres 2 ways you can do it, run pipes into a common pipe that feeds the MAP, or from just 1 body to the map as in theory they should all be the same, it works just about.

Main problem with just throttle pot systems is the low throttle openings, not precise enough with the pot.

If he wanted to do it properly then he would spend the money!

Level 7 User Joined: 27 Feb 2004 Posts: 243

for the map sensor i wud run a vac hose from each manifold runner to the map sensor, via t-pieces and stuff. as for ECU's im looking into the smt6 that gdi use. meant to be better than the dastek, and can be setup to run anything from ur original ECU. jsut waiting on the throttle bodies at the moment, then il start gettin the manifold made up.

jimbo

Forum Moderator Joined: 16 Feb 2004 Posts: 1356

Can't wait for the pictures!

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

I think an engine management tech article will be needed as well.

Gay Rights Activist Joined: 07 Apr 2004 Posts: 1268

Chris H wrote:

or from just 1 body to the map as in theory they should all be the same

but the pressure change isnt going to be as great with just one body is it? like u say, 'T'-ing of all 4 may work.

also wot (I mean what really) about NTC 1 (air temp)? the temperature at all four will be the same, but it measures temperature change, which will be less across 1 body as there is less mass of air.

spend the money!!! u can get an emerald ECU for Â£550.

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

I know Stan, but hes wanting to do it cheap, these set up sare not very good but they work which is all that matters at the end of the day.

Leave them to it my friend.

Forum Moderator Joined: 16 Feb 2004 Posts: 1356

A student with Â£550 in his pocket lol You've obviously not been a student for a while! Wink