Tuning the FI lude... - Honda Prelude Forum

walude · 02-22-2002, 07:42 PM

Maybe some people who have some JRSC or Turbo experience can help out here.
I have seen quite a few questions about tuning all over the board with no real answers. I am ordering a JRSC as we speak and I will get some place to tune it but how do I know they are doing it right? What are the basics of tuning the A/F ratio so I know they aren't just mucking things up and telling me they know exactly what they are doing???

Quaalude · 02-22-2002, 09:18 PM

The place u are going to needs a dyno and wideband O2 sensor to correctly tune your car. Without the wideband, the place would just be guessing the a/f ratio. They will be able to extract horsepower with the dyno, but u might be running too lean in a certain RPM and u couldn't tell if u were.

walude · 02-22-2002, 09:19 PM

Quote:

Originally posted by Quaalude
The place u are going to needs a dyno and wideband O2 sensor to correctly tune your car. Without the wideband, the place would just be guessing the a/f ratio. They will be able to extract horsepower with the dyno, but u might be running too lean in a certain RPM and u couldn't tell if u were.

How can they adjust the fuel output at specific RPMs?

xtal · 02-23-2002, 12:30 PM

The only way to do that specifically with with a standalone or something like a VAFC (adjust fuel response at a specific RPM).

Get your car wideband tuned. This is the most important thing you can do! Wideband sensors are getting a little cheaper now, and if you poke around on some of the domestic forums you'll see guys installing them permanantly. It's a great tool to have, expensive though. It's also interesting to note that in the SAE journals manufacturers are looking to move to better O2 sensing as a lot of new engines are being designed to run -really- lean for fuel economy.

Wideband tuning will give you a graph of the A/F ratio over your powerband. Then you can set it to an ideal mixture.

Myself, and I think OOG and others are looking at a piggyback module that can take the injector signals from the ECU (in addition to a RPM and perhaps MAP signal to detect boost) and shorten/lengthen them to do tuning.. lots of gadgets to do this are out there, lots of techniques.. they just cost too much heh.. A $10-15 AVR and a $5 ADC would do the trick, time not included. hehe

Steve

walude · 02-23-2002, 07:41 PM

So it sounds like a V-AFC would be a very smart thing to install along with the JRSC. Then go find someone who can set it up correctly.