Street trim track results. I have a couple of questions.

[ross87t]

Went to track in "street trim". Have a couple questions.
I took the Buick out to Houston Raceway Park last night. I simply put a few gallons of 93 octane in it, put some MT et streets on it, and lined it up.

My first run
60' - 1.672
330 - 5.208
1/8 - 8.227
MPH - 81.00
1000 - 10.868
1/4 - 13.115
MPH - 99.57

The car seemed to just lose motivation after about the 1/8 mile. After hitting recall on the Scanmaster, it showed 5.4 degrees of knock. I wanna say the O2s were around 800? Stupid me forgot to remember that value.
This was w/ around 19psi of boost w/ alky injection.
I then up the fuel pressure to 43psi w/ the vacuum line off, and get back in line

In line, I decided to check and see what chip I had in it. I don't drive the car too much, so I had forgotten what was in there. Turned out, it was a Conley Minimag chip.
I pulled that one out, and replaced it w/ another chip I had. I don't know it's specs, but it says T1B on it.

With the mystery T1B chip, I ran the following:

60' - 1.704
330 - 5.177
1/8 - 8.134
MPH - 83.24
1000 - 10.715
1/4 - 12.922
MPH - 101.16

Here's the kicker. With just the chip change, boost went from 19psi up to 23psi. I noticed I was getting a fair amount of knock through the entire run w/ a max of 14.2°. The average was about 10°

Here's the question. Why such low MPH? I figure on the second run, the MPH was low due to the excessive knock retard.
Do you think if I would have had the boost lower (around 19 or 20psi) on the second run, there would have been less knock resulting in a better et & mph?
It sure would be great to run about 105mph and some 12.50's in street trim.

One thing I can say is that the launch freakin rocked!!!

Car has the following mods:
Hotwired 340
adj. fpr
Bluetops 36#
9" K&N w/ MAF pipe
Hooker catback w/ testpipe
2800 stall D5
rear aibags
BMR tubular lower LCAs
SMC alcohol injection

I had ran it once in street trim w/ the stock converter and it ran 13.0 @ 105mph w/ around a 1.85 60'

Do you think this converter could be junk?

The elevation of the track is a little below sea level, the temperature was around 55°-60°.

I did notice this morning that the vacuum line that plugs into the heater water valve is broke in half. Could this have anything to do w/ it?

I have a brand new set of Comp Cams 980 valve springs in the garage. I imagine those should help w/ the top end charge.

Like I said though, the 1/8 mile felt real good.

Ross

 

[Snorman]

I was getting a fair amount of knock through the entire run w/ a max of 14.2°. The average was about 10°

Damn...that's a ton of KR.
Just look at your 1/8 mile speeds. You were up over 2mph, but were up less than that at the 1/4. The KR killed you. Personally, if I saw that much KR, I would have aborted the run.
I tune for no knock, you might consider it before you're changing a set of head gaskets...or worse.
Nice short time on that first pass...stock suspension?
S.

 

[BoostKillsStres]

I'd say go ahead and do the valve springs, could only help. Next, lower the boost and get both chips boost levels tuned on the street if you have somewhere good to do it with no side roads, houses or traffic. Document how many turns of the WG rod you needed between chips then head to the track and find out which one works the best at zero knock or just a tickle.

Good luck, its all about the tune.

 

[ross87t]

I also have an LS1 MAF, Translator +, and an extender chip burned for alky and my setup. I'm going to install those this week and wait to tune for the new chip.

My suspension upgrades consist of rear seat braces, rear airbags, and BMR tubular LCAs. It hooked hard on a 10psi launch!

Ross

 

[jetmech]

Just remember the cooler the weather the more fuel you need and hotter the weather the less. At 55-60 degrees you
may need a little more fuel press. Also start out w/ less boost then turn it up a turn at a time. You dont want to blow the
engine on the first run. When you get the translator on set the fuel press. to what is recommended by the chip, if its
cooler out add some fuel till the c ar slows down then you can lean it back down a little. Last year i was at the track
in 95 degree heat and could only get like 13.3's until someone said whats your fuel press. at. It was at 45psi. they
had started their fuel press. at 41 that day and was down to 38psi. After i turned mine down to 42 i was at 13.05. Also try for a MAX of 3-4 degrees of KR.