Slower with tc78 than pte67???
08-08-2008, 12:26 AM
#1
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Slower with tc78 than pte67??? I just got back from the track with the new tc78. I could only manage a 10.93 @124,1.65ft With the pte 67 a couple months ago i did a 10.82@122,1.52ft.
The car would not launch worth a crap. I tried the 2step and it would push the brakes. I tried just stalling it up but could only make it to about 2300rpm and was launching with no boost.
The car feels alot faster than before but my times suck. Also im getting a weird delay on my 2-3 shift.it falls on its face right before it shifts then moves again.
Im sure this isnt the turbos fault,im just kinda pissed at the times.
My goal was a 10.5@125.
Alex
The car would not launch worth a crap. I tried the 2step and it would push the brakes. I tried just stalling it up but could only make it to about 2300rpm and was launching with no boost.
The car feels alot faster than before but my times suck. Also im getting a weird delay on my 2-3 shift.it falls on its face right before it shifts then moves again.
Im sure this isnt the turbos fault,im just kinda pissed at the times.
My goal was a 10.5@125.
Alex
08-08-2008, 07:51 AM
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I was thinking the verter is off also. What do you guys think i should be running?
Im going to have to go in for a retune or somthing. It feels like the car hits a limiter right before the 2-3 shifter. Its really bad i thought i had let off the gas all the way.
Alex
Im going to have to go in for a retune or somthing. It feels like the car hits a limiter right before the 2-3 shifter. Its really bad i thought i had let off the gas all the way.
Alex
08-08-2008, 08:04 AM
#4
You need to lower your 2-3 shift point to compensate for the power with the converter. We run the Silverado SS with a TC76 @17psi at the track. I have to command the 2-3 shift for 4700 it to happen by 6400. I also have a lot of torque management on the 2-3 as its the hardest on for a 60e to grab while making power.
08-08-2008, 08:08 AM
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it is all in the 60 ft you need to try to come off the line hard
do you have ls1 edit if so lower the 2-3 **** 500rpm and 10 mph and add 200 rpm to your revlimiter
do you have ls1 edit if so lower the 2-3 **** 500rpm and 10 mph and add 200 rpm to your revlimiter
08-08-2008, 08:51 AM
#6
08-08-2008, 11:00 AM
#9
You have to tune the setup for the turbo. If the vertor is off on stall that will hurt your 60ft times. The mph already shows you making more power even with crappy starts. Also the larger the unit, the sweet spot moves up. Also give me a call....Tnetics called about a turbine housing for you???
08-08-2008, 11:42 AM
#10
A couple months ago....well that might make a difference too. If the weather conditions were cooler, the car will run better. If it taps the limiter for a second before the shift it will affect times. Are you logging your passes or just making passes with a new turbo without watching anything? In car WBO2?
If you were logging your runs you'd be able to get a good view on whats happening down the track. I bet if it feels like it going soft for a second before the shift, its pulling timing out...you might be getting some KR and the car is responding by pulling timing out.
If you were logging your runs you'd be able to get a good view on whats happening down the track. I bet if it feels like it going soft for a second before the shift, its pulling timing out...you might be getting some KR and the car is responding by pulling timing out.
08-08-2008, 11:48 PM
#11
Only 2 mph !!!! thats not that much power? i wounder if you are having BP issues in the top end? what was your 1/8 and 1/8 mph before and after?
Get the trans fixed before you can really judge...
With a jasons02z we have seen a 124mph run on a 2.0 60ft then next pass 122 on a 1.79 60ft just seems too run a little slower mph wise on a better launch
Get the trans fixed before you can really judge...
With a jasons02z we have seen a 124mph run on a 2.0 60ft then next pass 122 on a 1.79 60ft just seems too run a little slower mph wise on a better launch
08-09-2008, 03:45 PM
#13
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I'm back from vacation, oh how I miss the East Coast already.
So you can only footbrake the car up to 2300 and then it won't hold anymore? Does it start to spin the tires?
That 60 ft tells us that the car is not leaving real hard and probably not on any boost.
I'd fix the 2-3 shift, see what it's doing. If you could leave on some boost you'll drop down to mid to low 10's no problem.
If you leave off idle from a light does the car leave hard or is it a bit laggy?
So you can only footbrake the car up to 2300 and then it won't hold anymore? Does it start to spin the tires?
That 60 ft tells us that the car is not leaving real hard and probably not on any boost.
I'd fix the 2-3 shift, see what it's doing. If you could leave on some boost you'll drop down to mid to low 10's no problem.
If you leave off idle from a light does the car leave hard or is it a bit laggy?
08-09-2008, 04:47 PM
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Okay so here is my plan to get some good numbers before i say f it and get a t-brake.
Im going to relocate my cutout to directly after the down tube to try to relieve some back pressure that these kits are known for. I think that the reason it was falling on its face before the 2-3 shift is not the trans but maybe the fact that the boost was at 16psi and i only have a 2bar sensor. Im going to lower the boost to about 14.5psi.
Also i did notice that when i hot lapped the car it would hesitate before the shift but the last run i let it sit for 1hour and it was about 65degrees out and there was no issue.
Im going to rig up the 2step to the brake switch instead of the regular manual switch i have it on now. Its to hard to time the release of the brake and that switch. Ill set it to about 2200rpm and im seeing 2psi on the street at that setting.
Also im going to throw some 100 octane in there just to make sure its not pulling timing for some weird reason.
Im going to relocate my cutout to directly after the down tube to try to relieve some back pressure that these kits are known for. I think that the reason it was falling on its face before the 2-3 shift is not the trans but maybe the fact that the boost was at 16psi and i only have a 2bar sensor. Im going to lower the boost to about 14.5psi.
Also i did notice that when i hot lapped the car it would hesitate before the shift but the last run i let it sit for 1hour and it was about 65degrees out and there was no issue.
Im going to rig up the 2step to the brake switch instead of the regular manual switch i have it on now. Its to hard to time the release of the brake and that switch. Ill set it to about 2200rpm and im seeing 2psi on the street at that setting.
Also im going to throw some 100 octane in there just to make sure its not pulling timing for some weird reason.
08-11-2008, 12:42 PM
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I'd fix the shifting issue, and run the car again and see what it does. Worst case you need to tweak the converter to run better on the track though your car was quick from a 50mph roll.
08-11-2008, 01:07 PM
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Ive decided the 2nd week of Sep the trans is going to Finish line for a freshing up and a t-brake. Im also going to add a meth kit and go back in October for some low 10s.
Alex
Alex
08-11-2008, 01:55 PM
#18
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Hmmm I would run it again soon, are you worried that your trans is going out? If the trans is shifting late like that, you might be capable of running 126-127mph which would be pretty cool. When did you make peak HP?
08-11-2008, 02:06 PM
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I dont think its an issue with shift points. It had a weird hesitation before the shift but it shifted at the right time. I think the tune might need alittle work also. I wanted to get a restall anyway because i dont this this verter is matched properly.
If im taking the verter out i was going to have my 200+pass trans freshened up,if i have the trans at the shop i minus well get the t-brake i always wanted. Then im going to have it back on the dyno with slicks this time instead of spinning street tires.
Get the tune minted out the trans minted out and hopfully it will all come together for me at the end of the season.
If im taking the verter out i was going to have my 200+pass trans freshened up,if i have the trans at the shop i minus well get the t-brake i always wanted. Then im going to have it back on the dyno with slicks this time instead of spinning street tires.
Get the tune minted out the trans minted out and hopfully it will all come together for me at the end of the season.