RSKtakR

sooo we get the car strapped down, we wanted to get the N/A tune down, and then do a tune on the nitrous. so the first pull got 287whp, the next got 292whp. for some reason the car kept pullilng timing from 4100rpm's to 4800rpm's. the car did fine until he hammerd the throttle, then it would pull timing, and then right around 4800 the timing would go back up to where it would normally be (not pulling timing anymore).. my car is an auto w/a tci 3k stall, and all the mods listed in my sig, we had the trans locked in 4th gear, then we tried to let the trans shift like normal, w/ the OD turned off, and then while running on the dyno it still went into OD at 5500 rpm's.. we turned the knock sensors off, and it would still pull the timing. .WTF is going on here? is something wrong w/ the VCT's??? whats wierd is that the AFR is right on, no spikes or anything whatsoever. ? i have read that the hot rod cams dont need lockouts or phase limiters or anything, but my tuner is at a loss and neither one of us know wtf is going on.. they did the cam swap for me about 3 weeks ago. and im kinda pissed that i have all these mods and the car wont even laydown over 300whp? ? ? i was REALLY hoping to get 310-320whp... any suggestions would be GRAND.. i going to call John and Chris at BBR tomorrow and see if they can give me any suggestions. and my tuner is going to ask around to.. they have never seen this problem before, and they have built and tuned a couple auto s197's, there were 3 other s197's there so its not like they dont know wtf they are doing or anything.. any thoughts or suggestions??

candymanjl

power is in the timing so if it's pulling timing then it doesn't matter what the af ratio is.

honestly if your tuner was any good then he would be able to fix the problem. that's what a really good tuner does, anyone can play with timing and the AF ratio.

RSKtakR

we dont know WHY the car is pulling timing or what is telling the ecu to pull it... the only time it does it is when he floors it, it does for the RPM's i stated above, and then it goes back to normal.. and its not knocking either, we thought it mught be because of the stall, but it does the same thing locked in 4th gear, or w/ the OD turned off.

hammeron

hey RSKtakR, there are a few reasons why the PCM
might reduce timing.

Air Charge Temperature (usually taken at the MAF, for a N/A setup)
Engine Coolant Temperature
Cylinder Head temperature (maybe this is your issue?)
Knock detected

there might be more i'm forgetting right now, but i think those
are some of the big ones.

RSKtakR

he turned both knock sensors off and it still pulled timimg around the same time/rpm (when he floored it).. would the PCM still pull timing for the cylinder head temp, engine coolant temp, and air charge temp? and can these sensors be controlled to NOT pull the timing or arent these set up as a prevention and cant be altered?

siggyfreud

Traction control on these cars will pull timing. Perhaps the wheels are accelerating fast enough to enable this feature.

hammeron

i think the temperature tables can be modified,
but remember that they are safeguards designed
to hold your engine together.

07 GT E UPP

Hey there RSKtaR, sorry to hear man. I don't have any great words of wisdom here other than to say that while it can be extremely frustrating, i'm sure things will work out for you soon. Maybe he (your tuner) needs to touch base with other reputable tuners and get some additional input for your Mods. I know that all cars are very different and that dyno numbers are not everthing, but just to give you some additional info ,I had the exact same mods as you when I was NA and I got 346 to the wheels. Good luck ....!!!

RSKtakR

i dont think that is happening but i will ask him just to make sure..that would make perfect sence though since its only happening when he floors it, but i dont think its making enough power/torque to spin the tires on the rollers.

i thought those would be a safeguard, and may not be able to be modified.


hey thanks for that ..YOU SUCK!!! lol haha j/k.. but see? i know i should be getting over 300 whp. he was going to touch base w/ some other tuners today and so was i to see if we can find out what we are missing.

nite

did you check your plugs? i don't see a catch-can in your mods list... blow-by could be a factor.