How bad did I do?
08-08-2010, 04:53 PM
#1
Registered User
Thread Starter
Join Date: Aug 2010
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
How bad did I do? So I finally took my firebird out for its first passes down the track in about 2 years. I was pretty let down with the results but I'm hopeful that if I get some more seat time and tweak my suspension I might be able to improve my times.
Quick run down of my mods are a 408, ls6 heads, fast 90/90, 4L60, yank SS3600, moser 12 bolt 3.73 gear, afco singles up front and qa1 singles in the rear,. Raceweight is 3560 and the car was on a nitrous tune running I think about 18 degrees of timing. This setup made 505hp on a motor tune. I wasn’t at the shop when it was tuned for nitrous so I’m not sure what it made on motor with timing taken out but it made 680ish on a 175 shot. Tires are 27" mt drag radials.
a
The drive to the track was about an hour drive. Once I arrived at the track I went to tech the car and was in the staging lanes within 15 mins. This was a very unplanned decision to go to the track. I didn't even check the tire pressure but I had them set to 18 psi the last time I checked them
I did a quick burnout and stalled up the car a bit and resulted in a 11.5@120 with a 1.7 sixty foot. My next run I planned on just flashing the converter but after doing my burnout the car was having a little trouble idling and I ended up having to stall it up a little bit which resulted in another 11.5@120. The two runs were motor passes just to get an idea of what this set up might do.
IMO I think I have a few things that I think would really help. First, this tranny is just not liking the new power because on both passes I bounced off the limiter for a split second when the car shifted from 1-2 and 2-3. Second, issue is the car is probably lower that it needs to be for optimal traction. I measured the distance between top of the front fender arch and the floor and came up with 25 3/4 on both sides with the shocks being set to 5 and the springs are 325#'s. The rear springs are stock springs with the isolator removed and those shocks were set to 8 last time I checked.
My main plan before I go out to the track again is going to be get a turbo 350 or 400 in the car. I'm done fooling around with the 4L60. At the same time I'm going to get a nice converter spec'd and matched to my mods. Current converter was purchased used from a member but I'm not really sure what mods it was built for. After the trans swap I'm going to find a reputable shop or individual to scale the car and set it up close to where it should be so I have a good starting point.
So how bad are these results and is there room for improvement or do I just have a turtle in my possession? I would think the nitrous tune isn't helping but should I have a little more mph? I was honestly hoping to see something in the bottom 11's minimum
.
*Posted this here as I think I will get a better response and pointers compared to the results section.*
Quick run down of my mods are a 408, ls6 heads, fast 90/90, 4L60, yank SS3600, moser 12 bolt 3.73 gear, afco singles up front and qa1 singles in the rear,. Raceweight is 3560 and the car was on a nitrous tune running I think about 18 degrees of timing. This setup made 505hp on a motor tune. I wasn’t at the shop when it was tuned for nitrous so I’m not sure what it made on motor with timing taken out but it made 680ish on a 175 shot. Tires are 27" mt drag radials.
a
The drive to the track was about an hour drive. Once I arrived at the track I went to tech the car and was in the staging lanes within 15 mins. This was a very unplanned decision to go to the track. I didn't even check the tire pressure but I had them set to 18 psi the last time I checked them
I did a quick burnout and stalled up the car a bit and resulted in a 11.5@120 with a 1.7 sixty foot. My next run I planned on just flashing the converter but after doing my burnout the car was having a little trouble idling and I ended up having to stall it up a little bit which resulted in another 11.5@120. The two runs were motor passes just to get an idea of what this set up might do.IMO I think I have a few things that I think would really help. First, this tranny is just not liking the new power because on both passes I bounced off the limiter for a split second when the car shifted from 1-2 and 2-3. Second, issue is the car is probably lower that it needs to be for optimal traction. I measured the distance between top of the front fender arch and the floor and came up with 25 3/4 on both sides with the shocks being set to 5 and the springs are 325#'s. The rear springs are stock springs with the isolator removed and those shocks were set to 8 last time I checked.
My main plan before I go out to the track again is going to be get a turbo 350 or 400 in the car. I'm done fooling around with the 4L60. At the same time I'm going to get a nice converter spec'd and matched to my mods. Current converter was purchased used from a member but I'm not really sure what mods it was built for. After the trans swap I'm going to find a reputable shop or individual to scale the car and set it up close to where it should be so I have a good starting point.
So how bad are these results and is there room for improvement or do I just have a turtle in my possession? I would think the nitrous tune isn't helping but should I have a little more mph? I was honestly hoping to see something in the bottom 11's minimum
.*Posted this here as I think I will get a better response and pointers compared to the results section.*
08-08-2010, 06:01 PM
#2
505 rwhp or flywheel hp? Can you post the whole timeslip? You've got a long way to go on your 60', that's why your ET is suffering.
The fact that you don't know much about the converter leaves HUGE variable on the table, not to mention with the little info you've listed I'm going to guess that stall is much too low for the combo.
PLenty of guys are running big numbers on the 4L60E when built by the right company, but I agree with you in going with a TH400. Don't mess around with the TH350...do it once and get the 400.
The fact that you don't know much about the converter leaves HUGE variable on the table, not to mention with the little info you've listed I'm going to guess that stall is much too low for the combo.
PLenty of guys are running big numbers on the 4L60E when built by the right company, but I agree with you in going with a TH400. Don't mess around with the TH350...do it once and get the 400.
08-08-2010, 06:54 PM
#3
Your tranny is already not liking it is a good sign of things to come. Either go TH400 or at least a 4L80e with a decent converter and if your going to run the nitrous, make sure it is set for that or just get a nasty 8" converter.
Never expect your best run first time out. Thats why it is called test and tune.
Never expect your best run first time out. Thats why it is called test and tune.
08-08-2010, 07:33 PM
#4
Registered User
Thread Starter
Join Date: Aug 2010
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
94z28rag-I agree not fulling know what the converter was built for is not good. Im not gonna mess with this 4l60 though since this is like my 4th one now. On the gas the last one lasted two dyno pulls and let go on my first run on the street.
The hp figures I posted where rwhp. Ill post the full slips when I get home.
Blackscreaminmachine- I agree as well more seat time and fine tuning are needed. I know the suspension is not setup right at the moment so hopefully tweaking that and getting rid of this crappy trans will do the trick.
The hp figures I posted where rwhp. Ill post the full slips when I get home.
Blackscreaminmachine- I agree as well more seat time and fine tuning are needed. I know the suspension is not setup right at the moment so hopefully tweaking that and getting rid of this crappy trans will do the trick.
08-08-2010, 07:49 PM
#5
Hard to say with that 60ft and the trans issue, not to mention the N20 tune. I wouldn't even think to hard about it honestly man. Next time, be ready suspension wise especially. Get all that straight, and the other issuses, go back and see what it's really got. Don't blame you on the th350/400 tho.