79 Malibu first time track (Videos)
11-30-2016, 06:46 AM
#23
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The dump is a mechanical pressure regulator that we installed, we're dumping pressure to the converter basically.
The trans is a RPM 3 speed TH400, PTC bolt together converter. I know Rodney is doing some trick stuff with dump valves built into the valve body. I don't know how much they cost, but they're not cheap.
We do not use a bump box or anything of the sort. Only footbrake and trans brake, sure.. sometimes it would be nice to have a bump box but 99% of the time our method works just fine.
The trans is a RPM 3 speed TH400, PTC bolt together converter. I know Rodney is doing some trick stuff with dump valves built into the valve body. I don't know how much they cost, but they're not cheap.
We do not use a bump box or anything of the sort. Only footbrake and trans brake, sure.. sometimes it would be nice to have a bump box but 99% of the time our method works just fine.
12-11-2016, 11:55 PM
#25
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No transbrake in my car. TH475, reverse pattern MVB. I'm using Microsquirt to pull timing and set rev limiter (2 step). Tried just foot braking it with no 2 step and it's just pushing before I can build boost. I have a Quick 9in with disc brakes and didn't change my proportioning valve so I'm getting more grabbing power in back than front and I'm still pushing thru.
Went to the track yesterday and it was horrible. Peddle fest on the few passes I made so we loaded up and hit a different track today. Car hooked good. Played with 2 step for an hour trying different timing settings and could only get 5lbs boost at 3100. Either pulling converter to get it loosened up, putting a brake in it or both. Best today was a 1.6 60ft.
Not gonna turn the boost up until I can get off the line. Running 14lbs boost now. Once I get 10lbs off line, will go up to 20lbs and let it eat.
AFRs on car are 11.8 at full boost and only 14.5 timing. Don't want anything past 12.0
Here's a video from today. The Junkyard Dogs getting there.
Went to the track yesterday and it was horrible. Peddle fest on the few passes I made so we loaded up and hit a different track today. Car hooked good. Played with 2 step for an hour trying different timing settings and could only get 5lbs boost at 3100. Either pulling converter to get it loosened up, putting a brake in it or both. Best today was a 1.6 60ft.
Not gonna turn the boost up until I can get off the line. Running 14lbs boost now. Once I get 10lbs off line, will go up to 20lbs and let it eat.
AFRs on car are 11.8 at full boost and only 14.5 timing. Don't want anything past 12.0
Here's a video from today. The Junkyard Dogs getting there.
12-12-2016, 12:04 AM
#26
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I have a ptc that is supposed to stall at 4K but I can only get 3500 on foot brake and 2step. 3600/200 and +5 timing. Only difference is I'm throwing mine in 2nd gear on line to build more boost and not push threw lights. I keep it in 2nd and just tap it into 1st when I'm ready to leave with 8psi on the line I cut a 1.46 60 off the footbrake. Doesn't bang or anything and I've done it probly 30 times so far. Taking timing out didn't help me build boost but adding it did. Make sure your meth if u have doesn't come on til after 60ft cause that kills torque. And ur a/f should be around 12.5-12.8 on 2step with pump gas anyway not sure on e85.
12-12-2016, 12:06 AM
#27
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You need to keep timing in it to give the engine enough power to start coming up on the brake (when you have one), pulling timing will cause it to be harder to come up on the brake.
You'd be surprised how much timing is in the Race car I work on to help it come up on the brake.
You'd be surprised how much timing is in the Race car I work on to help it come up on the brake.
12-12-2016, 12:13 AM
#28
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12-13-2016, 04:24 AM
#30
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This one was suppose to be 3500-3600 but I'm only getting 3000-3100 out of it at best. Someone said engine was "detuned" but it's exactly where I said it would be. Turbos the same as it's always been. Just need to get 500 more RPMs to build boost. Seems like I'm right on the edge.
12-13-2016, 06:47 AM
#31
Mine is supposed to be the same stall speed, but mine won't go above 2750 rpm before pushing through the brakes. I've seen some peoples sig that says "you can't make enough power for a PTC" LOL. You should be able to make some decent boost at 3k though.
12-13-2016, 09:31 AM
#32
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I'm right on the edge of building boost. My cams even got +6 in it to pull rpm range down lower as well as a fully divided hot side. I've tried just on brake and no 2 step and I can build the same with timing up. Break tires loose before I can get decent boost no matter what I do. Even on 10.5 slicks heated with an extremely sticky track.