ITB's are GO!!!!

[Gavin]

I've been working on my ITB set up for more than a year now (as anyone whom has viewed my threads here would know), and though shes far from 100% I just turned that dirty bitch over 'avec ITB's', and SHE RAN!!!

YEAAAAA BOEEEEEEE!!!! Now I have to endlessly tune my fuel curve, because shes running monstrously lean, but I am pumped-up baby. It was so satisfying to listen to her turn-over packed to the gills with my hand fabricated parts.

Thanks to everyone who has offered advice. I'll bring my laptop home tomorrow to start tuning my fuel curve, and will grab my camera from the office and post a few pics.

I only wish I could have involved my eldest son in the start-up; but he got caught steeling the other day and one of his punishments was that he wont get to participate with dad in the BMW build up anymore (my plan was to build it with him, then give it to him as a surprise. Now I'll have to think about that).

[JasonC]

Great work. It's nice to see hard work pay off. I hope pictures will follow? To bad about your son, i know if i had a son that did that i'd wouldn't be to soft on him either.

[Fidhle007]

I love that feeling of putting your blood, sweat and tears into something and then when you turn the key, it actually RUNS! Congrats on the new setup, I eagerly await pictures!

[e30serg]

That's awesome! How/what are you using to tune it? Care to let us know?
Too bad about your son. I guess he gets what he deserves....

[Farbin Kaiber]

I say once it's finished the son gets to go on the innagural run via a bicycle on the sidewalk as you in the drivers seat take off in a cloud of smoke. That'll teach him.

[Gavin]

Here are a few shots of my efforts. Ignore the intrusive heater-core plumbing protruding from the firewall, that’s just temporary until I figure out some hard-lines to clear the throttle-bodies. Also, the loose wires connecting the TPS will be cleaned-up & loomed (that was done quick & dirty so that I could rewire easily if I had patched the incorrect wires).

That's awesome! How/what are you using to tune it? Care to let us know?

I want to retain the factory computer, as to maintain all of its functions (like AC, cruse, & warning lights). I’m using a URD (underdog racing development) signal calibrator to modify a TPS signal & replace the AFM. This will cover my idle & base fueling needs, alpha-N style, via the factory 6 injectors & factory ECU. I’ll use Megasquirt to control the up-stream 6 additional injectors, keying on MAP signal, to handle supplementary fueling. I’m aware that I could just upgrade to larger factory style injectors, but I already had extra injectors that came with the GSXR TB’s, I thought I may as well use them, and having 12 injectors looks damn sexy too boot.

[Farbin Kaiber]

12 injectors look like something else. Are you running both sets at a lower duty cycle to balance the extra fuel out?

[Gavin]

12 injectors look like something else. Are you running both sets at a lower duty cycle to balance the extra fuel out?

Yes, basically. I’d like to phase them so that the up stream boys come in at higher RPM.

I was surprised at how lean my closed-throttle idle-only start-up yesterday ran, 16.8:1 AFR. Though I have yet to touch my timing, and that will have an impact as well I suppose.

[KevlarWeave]

six o2 sensors later and you could tune each cyl via the multiples, no?

[Gavin]

six o2 sensors later and you could tune each cyl via the multiples, no?

If I were interested in self inducing a brain aneurism then TOTALLY! :D

[yberther]

hotness.
needs carbon velocity stacks :) :)

[dmoney(AB)]

That is awesome Gavin, you have to make it to the sylvan lake meet in july.
I want to hear that thing revving. Sweet 6 cyl music to my ears.

Congrats on finishing your project.
Now I just have to finish mine :p

[Elliot]

are you palning on dynoing the car? I am trying to decide between ITB and a custom intake manifold with a single throttle!!!

[Gavin]

I will be running her on the rolling road once all is said and done, & will be happy to share my results. But in all honesty, I did all this only for the sake of my own interest; just because this is something I’ve always wanted to try. There are much more time-efficient ways of improving performance. Unless you’re like me and will derive all the satisfaction you need from the copious amounts of character a screaming set of 6 wide open trumpets provides (hand fabricated by your own two) just buy a turbo and you'll be able to spank my car.

I haven’t spent a lot of money getting my car to this point, as I have hand fabricated everything myself using second hand parts. I have however burnt through a hell of a lot of time!

[SpecM]

-Wow... anything else done to the m20?