Help - Car got stage fright at the track!

[NHRA Super Gas]

Let me start by saying this car is an absolute animal on the street, and is in perfect tune. No BLM nonsense, IAC and all settings perfect. My tranny builder and one of my best friends (both of whom have been into the running 9's or better for years) both come away with huge grins and nothing but compliments for the car when they've driven it. The car seemed to be really lazy down low yesterday, and again at the top end. But even with that, it seemed to be down on power mid track relative to what it does on the street from a roll. When we left my buddy was following me and he said the car was 3x faster on the highway leaving the track!

The best I can figure had one or more of the following problems:

1. Knock: I had a little bit of both types, but when you see 19.9 @ 29mph I have to assume it is false. I just checked the TT site and saw the ignore feature is "if requested". I think I need to check this out.

2. Launch: I need to do some sort of brake upgrade, but the bottom line is the best 60' was around 2.0. It seems really lazy for probably the first 30 feet, not sure why. One thought I had is perhaps the alky is drowning the motor a bit that early?

3. Top end: The car seemed to layover considerably at around 105mph, or about 5000-5200 RPM. Motor is fresh, valve springs should be fine. Do I have a spark problem? I do still have the volt booster on the car, is this the problem razor and others had seen where with big voltage you're really dumping alky in?

Any inputs are appreciated....gotta do better next time!

 

[ES1]

I could see how the car would be flat down low because timing would be pulled with the high knock.
Running rich, to much alky, & rich knock could lead to the poor low end times.

On the top end, what were the O2s & voltage?

 

[NHRA Super Gas]

Rich Knock...

My first two runs were at 21lbs boost, 10% add'l fuel added via the TT chip. Alky knob was either 6 or 7 all night. This was with 100 octane and pure methanol. Then bumped to 24lbs. First pass with 24 was the best of the night. From there it was hard to duplicate. Looking at the time slips, with my notes, I had a couple of 789's at 97-99mph, and many of the passes I had one eye on the scanmaster. Generally we were 800ish dropping down to 790's through the traps. There was some knock on the high end where you would expect it. But as I review the passes, I see 6degrees KR at 30mph, 9 degrees at 40mph, where would that come from if the car is doing well up top? Again I'm assuming those are false.

 

[ES1]

This is where a data recording scantool is a must.
It would be nice to see where all sensor readings were at on the runs.

Having re-read Razor's tuning with alky, he suggest fuel be pulled & alky added.

Knock is sometimes recorded on shift points but it appeared you had some knock after the shift point.

I would remove the volt booster and do a run.

If this does not work, you might want to go back to step one.
Turn boost down to 14-15 psi, turn alky off, and see what kind of knock.

 

[Razor]

Not really enough data.

If the car see's fals knock, it will pull timing. Also having a volt booster will flood your motor with alky. I would take that off. If you hit the motor with too much alcohol, it will nose dive.

Next, a 2.0 60 foot is either spinning like crazy or your not leaving with enough boost. It has nothing to do with alcohol.

Now.. concentrate on one part of the track.. lets say 60 ft.. now practice fixing this.. and not worry bout 60, mod track.. and top end all at once. As the saying goes, you need to establish seat time and sort it out.

HTH

 

[NHRA Super Gas]

I did just verify that the car has a hotwire kit as well as the voltage booster. Disconnected the vb and went for a ride. Lined up against a friends C6 vette and was able to pull on him pretty good from a roll, and those look to be mid/low 12 second cars. I was lean at first, added some fuel and the car really seemed spot on, 780's 0.0 at 97 mph for example.

I agree with the above comments about direct scan. Is that the best option for laptop based tuning?

 

[ES1]

The best out there now is the recording scantool from Full Throttle.