i tuned my car to 11.2 afr in 2nd gear, the car runs 10.4-10.6 in 3rd through 4th gears. a friend said its because my loads points or something like that and i have less load in the other gears??? i havent had this problem with any other car. any ideas?

 

tune it in 3rd. It takes longer to reach redline but you aren't going super fast like you would in 4th or 5th.
I also noticed this when I datalogged a complete 1st to 5th (to redline). It gradually got more rich in each gear.

 

I think I read a message from either Shiv or Al that there were different load tables or compensation tables for each gear i nthe OEM ECU. It makes sense; the type of load experienced at 2,500 rpm in 5th gear is different than at the same rpm in 2nd gear, at any throttle position.

 

I usually tune in 3rd gear, and whatever I tune the AF to it's a good half point richer in 4th. I've never really logged in 5th gear so don't know if it runs even richer there.

I posted a similar post in the utec forum, but the answer i got back was that maybe the ecu was getting knock and so switching to a richer map. The experiences of this thread show my observation to be true , as noted by the original poster. The ECU changes the map from gear to gear.

 

Yea, I noticed the same thing. It seems to run leaner in 1st and 2nd when compared to 3,4,5. Also no matter what I can't seem to bring it down at near redline. It always seems to go lean no matter my settings when near redline in 1st and 2nd. btw, 10.5-11.0 is pretty decent if you run the car somewhat hard.

bryan

 

if you tune your car in third then wouldn't you have to worry about being too lean in first gear? getdiesel

 

It is only slightly leaner, but the engine is under less load. I have experienced any knock or timing being pulled in 1st, 2nd.

 

you are knocking in 1st and 2nd? or was what you said a typo? im a little worried now about tuning in 3rd gear because it running leaner in 2nd gear. i may try it,, gees , its hard to believe i may be able to get more power out of it.

 

I ment to say "Haven't experienced", sorry. I shud reed watt I rite, .

 

i thought that was what you meant. so, should i tune to 3rd gear now... and get more power? btw, what boost are the majority of people running when tuning to 11.0-11.5? im running 19.2 psi, this was enough to smoke a 04 cobra by 4 car lengths!

 

What engine management are you guys using? Utech? Is there a guide on car tuning that I can get? thx

 

another monkey wrench into your equations/ideas/thoughts

What WBO2 sensors are you using ?? for a run in 2nd gear, it takes approximately 3 secs ..
That means each 1000 rpms takes less than 1/2 a sec ?? meaning the normal affordable WBO2 refreshes at 10hz .. maybe it's too slow to pick up the changes ??

And you get more rpm time when you're in higher gear .. hence more time for the O2 to stabilise and give you 'more' accurate readings ??

 

what are you using to tune your fuel IE, AEM, Utec, Exed etc

 

i am using a bosch 5 wire unit by zietronix. doing my logging on my laptop. getdiesel

 

i use lm1 with the bosche 5 wire. it reflashes every .4 seconds it says. i use emange to tune.