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Discussion Starter #1 (Edited)
Took my coupe to VMP this weekend for Cival Wars. On a good note, I won True Street on Sunday, but not in an index I wanted to run in.

Passes were very consistantly in the 12.77-12.85 range. Each 1/8 pass was 8.1-8.2. RT's were .250-.4 (need practice I know), short times were 1.65-1.75. Going through the traps in 4th @ 5200 and at 104-105 mph.

Did not run on the bottle, all runs were N/A.

Seems like it should have more in it.

Car is a coupe, stock bottom end 302, TFS track heat top end kit, TFS stage 1 cam, MM lowers, UPR adj. uppers, 90/10's with coil overs, KYB adj rear shocks, 31 spline 3.73's with 26" ET Streets. Was lauching at 4200, no spinning or chugging. Car felt good, just fell off from the 1/8 on down. Car is tuned via SCT software on a somewhat safe tune. A/F was in the 12.8-13.2 range during the tune. 24 lb injectors, 40 psi FP, etc.

I know my RT needs work and my 60's will improve some, but the car should be a low to mid 12 car IMO.

What do you all think?
 

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whats with the low rpm on the big end, it needs to be way higher then that , needs to be coming up on the red line of the cam
 

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Discussion Starter #3
whats with the low rpm on the big end, it needs to be way higher then that , needs to be coming up on the red line of the cam
That's where my main issue lies I think. I am just not pulling that hard in 4th. Each shift is at 6000 rpm. In 4th it just doesnt pull that strong.

I have a 100 shot ready to run. I didnt spray this weekend cause the car was so consistant. Next time out I'll spray and see just how much improvement that gives me 1/8 mile and down.

I could swap to 4.10's but I think it'll kill my 1-2 shifts.
 

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Unless there is a typo on your trap RPM or tire diameter I do not think you actually have 3.73 gears. 4200 in 4th with the 26" tall tire and 3.73's is around 90 MPH. The trap RPM and tire size you have listed puts your gears in the 3.08 or 3.27 range. If this is the case then a gear change will definately get you to mid to low 12's. Good luck with your project.
 

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Discussion Starter #6
Cam is a TFS stage 1, installed straight up

I for a fact have 3.73's, I installed them myself. I meant to say 5200 rpm at the traps (I'll correct that).

The car is built for the True Street type of events. Its my DD and occasional weekend drag car. I'll build and install a 331 over the winter just to ensure a solid engine for all of my driving with it. I'm not looking for a 10-11 second car, but I thought I'd have a solid low 12 car as it sets NA.
 

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Once had a 306 in my coupe with identical parts as yours minus the SCT stuff and an F-Cam instead. Also had 3.73's and the same et streets. Went 11.90's
 

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Discussion Starter #8
Once had a 306 in my coupe with identical parts as yours minus the SCT stuff and an F-Cam instead. Also had 3.73's and the same et streets. Went 11.90's
That's what I have read to expect out of mine. So with my rookie drivving, I was expecting low 12's for now. Something's just not quite right with it.
 

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Hey Tread, I saw you run Sunday, congrats on the win and good luck with your car. I'm sure you'll get it to pick up.
 

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What was the weather like? I would think you would run much quicker. You are losing MPH on the top somewhere it seems. My car runs 13.2x at about 102-103 with a stock motor from tb to oil pan.

How aggressive is the timing curve in your tune? Is it a tune intended for your future 100 shot? if so it could be pulling timing out.
 

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Discussion Starter #11
What was the weather like? I would think you would run much quicker. You are losing MPH on the top somewhere it seems. My car runs 13.2x at about 102-103 with a stock motor from tb to oil pan.

How aggressive is the timing curve in your tune? Is it a tune intended for your future 100 shot? if so it could be pulling timing out.
Definately the car is not making enough speed on the top end. The tune is for NA runs and general street use. The tune controls timing somewhat conservatively I know (90k stock bottom end, being safe).

Chris @PAS is gonna get her on the dyno and see what else we can get out of her. The car seems like a dog in 4th. 1st and second it pulls hard as all get out. 3rd feels "ok" and 4th is weak.

We'll do some tweaking before the next race and see if we can wake her up.
 

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Discussion Starter #14
typical 255 pump, 24 lb injectors, 93 octance, 10* base (the tune takes care of all advance via a custom timing curve)

My tuner was at the track with me and actually rode with me in the car on the cruise portion of my run. He felt nothing out of the ordinary at all. We're gonna tweak the timing curve a bit and see what happens. The car has awesome driveablity on the street and track. Just seems it should pull a bit harder at the track.

Temps were 75 and overcast Saturday. The track was a bit loose. Sunday was near 90 and sunny with a very sticky track.
 

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A/F was in the 12.8-13.2 range during the tune. 24 lb injectors,QUOTE]
What was the A/F at the track?? What is the total timing at peak??
 

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Discussion Starter #17
How does the car run without the SCT chip in it?

I would try disconnecting the neg batt cable, pull the chip, then set the base timing to 14-18 degrees and see how it runs.
Thought about it. But before the tune, with the TF top end kit installed, my AF was at 22.5:1. We used 2 widebands to verify the AF pre-tune. Based on that, I'm a bit concerned to drive it much.
 

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Thought about it. But before the tune, with the TF top end kit installed, my AF was at 22.5:1. We used 2 widebands to verify the AF pre-tune. Based on that, I'm a bit concerned to drive it much.
Wow. 22.5:1 really? Somthing is not right with that. To be totally honest with your mild setup and it being N/A I was wondering why even use any tuning software like SCT. I agree with rdub79. Take that out of the picture, tune it and see how that does for you.

Like I was saying earlier I had almost the identical setup, but no tuning software and The F-cam worked great with it.
 

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22.5:1 a/f without the tune?? As said, something is wrong there for sure. Are you sure the MAF and injectors are appropriately matched? You sure the injectors were not modified to flow more?

My old EFI 347 setup ran mid 11s on motor without ever putting a chip in it. It was 77mm Pro M, 30 lbs injectors, 75 t/b.

Take out the chip, set base timing around 14-16 degrees or remove the spout and run it at 30-32 degrees and see what happens. My twisted wedges liked a lot of timing.
 

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Discussion Starter #20
Injectors were brand new 24 pounders NIB when I installed them. MAF is a Pro-M, calibrated for 24's also was NIB. PCM is an A9L. FP is set at 40 psi w/o vacuum. Initially I had timing set at 14* pre-tune. Car ran well, but chugged and lurched a good bit.

After tune, the driveability is great. No hesitations, no stalling, couldn't be happier in how is runs day to day.

Like I said, my tuner's gonna play with the timing and go over everything before our next race.

AF was definately 22.5:1, I was there for the tune. The second wideband indicated the same readings. After the tune, the AFcame down to a much more safe and acceptable level as stated earlier in the thread.

I am hesitant to pull the chip and run the car aggressively due the excessive lean condition it had previously (stock calibration in PCM).
 
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