Weird AFR dips between shifts, ideas? OBD1/Crome
 

So my car has been running a perfect 11.8-12:1 AFR in WOT, never had any troubles.

Until last night at the drag strip

between each shift, when i got back onto the throttle, it would hesitate for a split second. Lucky for me I datalogged the passes.

For whatever reason, that hesitation is a dip in the AFR's to almost dead on 10:1 (sometimes 10.5 or 10.9:1) but I can tell its holding me back pretty badly.

Question 1: Could this be a symptom of a blown headgasket, I've been wondering if I've lost that cause I have a coolant leak and I cant find a dripping hose, just losing coolant and I can see it on the undercarriage. I plan on doing the ARP's and a new HG as soon as I can (money $$ ::))

Question 2: my clutch was slipping pretty bad too, could it be a side effect of that?

Car still idles normal, still pulls hard, doesnt smoke...

thoughts? comments? suggestions?

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

Sound like you need to work on your Throttle Tip-in when tuning.

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

sounds like spanish. i was watching it more tonite and it looks like it actually dips to 10.9:1, then as the rpms climb, the AFR's do too, a tenth of a point at a time, so maybe i just need to lean some ---- out. seems to be 4000-5000 rpm range, ill post the datalog in a few when i get on the laptop.

here it is
the datalog is attached, change the file extension from txt to zto and open in zeitronix datalogger software.

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

Zeitronix datalog software ;) http://www.zeitronix.com/images/disk1-V2.0.1.zip

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

sounds like you need to adjust tip in.

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

still sounds like spanish, guess i need to figure out what that is, and how to mess with it.

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

what's your 'fuel modifiers' (if using uber), 'individual fuel multipliers' (if using crome) set at?

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

this is with crome, im looking for those settings, not sure where I'm supposed to be looking, but I guess if I look long enough I'l find it right?

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

fuel tools (calculator icon in toolbar) -> advanced

Re: Weird AFR dips between shifts, ideas? OBD1/Crome
 

there are for fields, main fuel, o2 correction, startup, tip in, all set to 1.000

really odd, i was looking at those earlier and they were greyed so i couldnt change them, opened it again to look at the names on the 4 fields, and they're no longer greyed, very odd. sadly im not gonna be able to do much about this now for a while cause i cant datalog, my laptop is buggin out on me again, i think it possibly fried memory again. poop.

TurboEF9 was talking to me in the beachhouse, doesnt seem to think its a tip-in issue.