i just got corky bell's maximum boost and i know the importance of
tuning a turbo but i have a few question.

how do you actually go about tuning. my hrc kit hasn't arrive but let's say the a/f guage is reading lean (which is bad). what do you do in terms of turning? i know that it is not getting enough fuel so what do you do?

as far as gauges go, i know i'm getting boost, a/f, egt. do i need an oil temp guage, voltage guage, fuel pressure guage, air intake temp guage. ALSO how do you tune with these?

sorry, i'm just trying to picture how this process goes.

also, if you know of any webpages about tuning turbo 2g dsms, especially hrc stage 1 or 2, that'd be sweet.

what does WOT stand for? i keep reading it.

New Car:
2004 350z base, Nismo CAI, pioneer avic-n1 (dvd, cd, navi)



Old Car:
1998 GS with hrc stage 2, HID 6000k conversion kit, AEM UEGO wideband, sfmu, ml, prokits, Greddy warning gauges: egt, boost gauge, and oil pressure, apexi tt, haydans tranny cooler, costum dp, groundwires, dynotune fp gauge. gst muff, turbo spoiler
Boostin since Aug 03.

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!

welp, u shud really do a search, but the best a/f ratio is 14:1, and we get that at about 0.88 a/f
when using an egt to monitor exhaust temps, you do not want to be hotter than 1600 ferenheit, or you will start melting pistons

by using an a/f and an egt, you can narrow your tuning window rather easily by monitoring these guages. by using datalogging software, and looking at your long term, and short term fuel trims, you can pinpoint lean spots/rich spots, and with an SAFC, can adjust them accordingly...

even though most of us have 420a's, every engine is slightly diff, so no one of us can/will be able to tune the same as another 420a, and get the same results. it is all on sort of a case by case scenario...

i hope this helpd. to get the best tuning, u will need a dyno, and a wideband o2 sensor....

good luck, and im sure that others will comment, but in the mean time, search a lil more for tuning info, and past posts in the turbo forum....

once you are boostin more than 12psi, you have to worry about timing since the ecu will add/take away some depending on the situation...

an a/f at about 0.9, and a egt at 1500 ferenheit is where i wanna be, but i dont have to worry about that yet, im still as rich as they come from the factory.....

03 srt-4 13.130@112.47mph (n2o, stock turbo, 10/2003)
now: 20g, portfueler, bpu+++ (track/dyno times tbd...)

i farted on your wiki

great qustions. i know id like to know more about tuning as well, and theres probably others out there too. i have somthing to add: what do you mean by "long term and short term fuel trims"? explain it to me like im really stupi .

:shhh: i do cocaine :/shhh:

Tuning is def an art. You do most essential tuning by adjusting the fuel pressure. By doing this, it will either put more fuel into the engine, or less fuel into the engine. All turbo cars need an adjustable fuel pressure regulator IMO, for proper tuning. The vortech SFMU does this very well, as does the Super Air Fuel Controller. With an adjustable FPR, you can make it run richer/leaner at idle, during normal vacum conditions, and under boost conditions. The use of a datalogger will be invaluable, as this will show you exactly how the engine is running. Short term fuel, and long term fuel trims are terms meaning how rich or lean the motor is running in comparison to the stock fuel map, pre programmed into the ECU. Fuel trims will be displayed on a datalogger by percentages. 0 % is the stock fuel map setting. So lets say you are seeing a positve 15% on your short term fuel trim. This means that that from a very short time frame, the ECU is detecting a lean condition, and is richening the mixture by 15% over the stock fuel map. So lets say you get a negative 20% on your long term/or short term fuel trims, that means that the ECU is seeing a rich conditon, and is trimming fuel by 20% over the stock fuel map. Long term fuel trim is what the ECU is adjusting for over a longer time frame. Short term is what the ECU is adjusting for at near that same moment, or within several seconds, or minutes. WOT simply means wide open throttle. This is basically anything over 80% throttle plate opeining, or when the pedal is to the floor. Its VERY important to tune your engine by your fuel trims, as you want to get it as close to 0 as you can, as that is the stock fuel map. I had to do all that when i upgraded to larger fuel injectors. They are spraying much more fuel, so my fuel trims were reading all negative numbers, which means the ECU is trying to lean out the fuel map. I had to lower my fuel pressures at all engine operating conditions to make the injectors spray less fuel. Thats how you tune. WOT tuning can be done by reading your o2 voltages. Basically, you want to achieve around .93v at WOT, in 3rd or 4th gear for an manual, and .93 in the final drive gear for an auto. Proper tuning results in max power from the engine, and a much healthier running engine that will last a long time, not to mention reduced chances of detonation, but thats a whole nother topic

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)