DIY ITBs, Do It Yourself Individual Throttlebodies! With pics! Options

[Pivot]

This thread will be an ongoing How-to article on installing Individual Throttlebodies from a 2004 Yamaha R6 onto a 7afe(ae102).

The first few installments will be purely mechanical, and will assess designing a bracket, figuring out how modify the fuel system on the engine, and fabbing up a plenum and with spots for most sensors(haven't decided on the EGR system yet). Towards spring, I will be installing the entire setup and fine tuning it.

This really is a grassroots mod, and i don't believe it should cost much more than $200 if you know where to look for parts and how to do basic welding. I bought my ITB's off ebay for $20, so the stuff is out there.

Any comments or suggestions can be posted at anytime, however please make sure they are relevant to this thread. Thanks and enjoy.

*pics will be up soon of the ITBs

[Pivot]

I think i've researched it enough to make a competent design. My ultimate goal isn't exactly horsepower, but more or less a smooth flat torque band.

I'm using 38mm ITBs with long stacks to improve intake velocity and still maintain a good throttle response. I will be mounting them about 90mm from the head to keep response good, and use long tapered stacks to increase velocity. The plenum will be a box type, about 3 liters in capacity if i can shape it right. The shape i *want* would be a trapezoidal with the small end facing the engine. The stacks will lead in about another few inches inside the box. 38mm for the ITBs is a decent size for the oversquare 1.8l, it's not oversized for my aspirations. My hp predictions are relatively mild, only about 5hp max gain(on a 97 7afe). I have an automatic also, so i don't expect to see anything drastic. A 5800rpm redline isn't very inspiring on a 4 cylinder these days.

Kwanza used a good choice of words, this is more of a Test bed than an actual performance mod. My cousin in Canada is building a 3sge in an 89 camry, and if this works good enough for me, i'll try to build him a set. I also chose Yamaha as opposed to Suzuki or Honda in hopes that some sensors might be shared or have a same fitting, but i still have to cross reference. Kinda doubtful, but i may be suprised.

As for tuning, I'll be using a wideband to tune each cylinder. My goal is to buy a spare 7afe exhaust mani, and tap each runner for an o2 sensor. I'll just use one WB sensor and plug the other three runners while testing whichever cylinder. Since the Yamaha ITB's have various spots for tuning the amount of air entering from each TB(and it's mechanical), it'll take some time but it should be worth it. Remember, with ITBs we're able to tune each cylinder independently, so while the ecu gives a general direction to the injectors to fire at like 80%, the amount of air entering each cylinder can be tweaked regardless. I'll be using the stock maf(seems like a waste of time then, right?), but this is just a test. I'll also be using the stock injectors, just have them flow tested and maybe blueprinted.


The reason i'm choosing this path of tuning is because i recently acquired a brand new wideband controller. It's the Pivot Multiple Data Logger. Very "jdm" and Very discontinued. Ebay is the greatest, i got it for about $200 with WB o2 included. Anyways, the datalogger is able to display AF ratio, Injector pulse width, and some other Airflow related readings. Also has a tach... something my car doesn't have : )

I can understand the skepticism some of you guys might have, a few bad experiences regarding other members might put you in that state of mind. But I'm glad to hear some of you guys support me. Thanks.