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Discussion Starter · #1 ·
...even though I hate re-posts and/or cross-posts, I figured I'd post this here since the Engine Performance section is apparently just for talking about what you're gonna do, posting pretty pictures and bitching...

Hey all, I don't know if I'm having a problem or not, but I was pretty disappointed with my SOTP feel, regarding my new engine, and now my track times have validated it. For starters, the car is my 96 SS, 6 speed conversion with a refreshed 350 (bearings/rings) and ported AFR 210cc heads with a (I believe) 59cc combustion chamber and PAC springs from AI. Valvetrain consists of Comp Pro Magnum 1.6 NSA RR's, LS7 lifters, Comp chromoly PR's and a custom ground Comp 503 on a 109 LSA and 107 ICL. Intake is stock ported with a TPIS 58mm TB. Ignition is an ebay (all_ignition) opti (I've had good luck with these 3 other times and couldn't really afford anything else), stock coil, Taylor 8mm wires and (AFR recommended equivalent) NGK copper plugs. Fuel system is Racetronix wiring harness, Walbro 255 pump and Ford 42 lb/hr injectors (I have a tune for E85 too, and I wasn't sure if the 30's would be enough for that). It has CIA Tri-y's w/o cats and an OBD1 conversion. Lastly, the O2 sensors were new a few thousand miles ago, EGR & AIR are deleted, TPS & IAC are new, and I think the MAP is original, probably along with most other sensors...

Now, a little history...back in April of '07 I ran a [email protected] with a 1.90 60' with stock heads, cam, opti, intake (manifold), rockers, 52mm TB, CIA 2.5" export pipes, SLP headers and PCMforless tune.

I bought a used engine with a spun main bearing off the forum that had ported iron heads, a Crane 224 cam (214/220 and .482/.496" @ 1.6 ratio), Crane Gold 1.6 RR's, Comp PR's and put this all on my engine and changed to CIA budget headers w/o cats. In July/August of '07, on a rather hot and muggy day I ran a [email protected] (not certain on the mph, but around there), again with a 1.90 60' with this configuration...I then dismantled the car that winter with the intention of putting it back to stock and selling, but decided to keep it...ended up being a year, ordered the 503 cam and then the engine blew...FFW 2 more years and here we are.

The car has always had 2.5" Dynomax pipes with Hooker Maxflow mufflers, sewer pipe intake with a cone filter, a 160 stat, Currie lower rear arms and drag radials.

Now, on to why I think something is effed up. The car with the most recent mods ran a consistent [email protected] with a 2.1 60' in decent weather (about 65-70* and ok humidity) on 5-6 different runs. I know its running pig rich (exhaust, mileage and Datamaster) but I really don't think it would be affected that much as it was also rich after with the other cam (got about 10mpg the 1 tank I checked). The only thing I can really pinpoint it to would be the cam, possibly its install, as I didn't degree it, and the tune.

Now, I didn't degree the cam because I couldn't afford the "instruments" and it should have been ground correctly where I would install it with the timing gear marks lined up, right??

I just took these Datamaster files on Sunday (but am not very versed with its use yet) and the track runs were this past Thursday. I recorded the files as a F-car with MT since I have the 6 speed and I don't know if this screw anything up, but my speed was only reading 1/2 of what I was actually going. I also swapped the PCM, just to be certain, so the "xxxxxPCMQ" file is the first, "questionable" PCM, and the second "xxxxxPCMKG" is the "known good" PCM...at least that's whats operating my 94 9C1. Please let know what you think, and/or if I missed any vital info, but I think I got everything. I have the tune file too, if anybody wants to look at that, but I don't know if it would help. Thanks in advance.

-Jeremy
 

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What stall?





































j/k What format is your tune in. I'll take a peak if i can. I would agree on the rich running. Also too much timing. Your idle kpa is way too high, you never really acheive closed throttle idle. It is fueling as if its at part throttle at "idle"

chris
 

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Discussion Starter · #3 ·
lol yeah...Thanks alot Chris, I'll attach my tune file as well, in case somebody else asks. I use tunercat to load it, so its just a .bin.

Any ideas why my speed is halved? Could it be since I was reading as an F-body?
 

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Discussion Starter · #4 ·
bump....anybody else?? Cam installed wrong?

Chris, get a chance to look at the tune?
 

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Discussion Starter · #5 ·
bump again
 

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I apologize, It looks like the injector offset table is a bit off as well as the VE tables. Closed throttle timing is a little low for the 503. It looks like its time for a fresh tune. I would copy over your chassis settings and start fresh. The VSS info being doubled is the scan tool scalar needs to be reduced. Use the constants stable position to enter the value. If you can get the part number for your injectors, the i can look up the injector info.
 
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