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Discussion Starter #1
I am currently running a PTC 9.5 with the following specs/Part number: PTC-C6-SB-14-0-45-SL

Car is a mustang, about 3800lbs, 398ci SBF, twin 7675’s, AOD with MVB/TB, and 3.27 rear gear. When I had PTC spec it out, I planned on running the car at the track. Fast forward to now (2 kids, wife, job, etc.) and it's looking more like 99% street.

I think leaving off the brake with some boost the converter will do what it is supposed to, but messing with it off idle on the street leaves a bit to be desired. Right now it flashes at 3K and then labors a bit. Based on fuel consumption, peak torque is around 4,700rpm. Peak torque seems to be going up as we increase boost. I am only running off the gate with 6psi right now as we sneak up on the tune, but I don’t think that should make a difference since it flashes before it starts making boost, right?

Spoke to Layne at PTC briefly, he said just send in with a note saying what I want it to do. Not much help. The problem is, I am not really sure what I need/want it to do. If I ask them to loosen it 1,000 rpm, will I have issues with it being way too loose when I throw 10-12psi of boost at it?

Does anyone have any advice regarding how to proceed?

Thanks in advance!
Shaun
 

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The converter will act much different under full power at the track.
I would throw some timing at it in the sluggish low rpm area and get it to the track before pulling it apart.
Having time slips, shift rpm drop, etc will make it MUCH easier for ptc to make educated adjustments, if needed.
 

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Tune the car to the power level you want to race it at and then evaluate the converter. Converter is the last thing you want to change.
 

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Good advice from both these guys. It's amazing how differently the car can act when you get aggressive with the VE cells that border the 100 kpa/brake release area. Don't be scared to knock it in the head with some timing at low manifold pressure to wake it up.
 

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Discussion Starter #5
Thanks for the advise guys. How much timing should i be knocking it in the head with off idle?

I think part of the issue may be my ITB intake with really short runners is killing my off idle torque.
 

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The slip is based off the power you put into it. Get on the T-brake and leave at some decent boost and let us know how it goes. I ran the same converter on a super mild 370" LS. 30" tire/3.25 gear/1.76 glide. If I try to leave just flashing the converter it falls on its face. Leave on 8-9bs and it's a different story.
 

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Discussion Starter #8
I think we have 36 degrees of timing in it by 2,000 rpms.

So to be clear, i think everyone is telling me to forget about trying to get it to leave well on the street off idle? Like i said in the OP, the car will see 99% street use, so i'm not sure i care what it does off the brake/at the track once every couple years.

Am I going to ruin every bit of track worthiness by loosening this thing a bit? Is there a happy medium that will get me on boost faster off idle and still be fairly tight up top? My old converter was a 9.5" PI that was as tight as they could get it and it flashed at 6K on 8psi and i had no rpm drop between shifts LOL. Way more fun, but obviously correct for the application.

thanks for the replies everyone, i guess i have to think more about this.
 

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If you are really driving it on the street a bunch, I would think a looser converter would make it feel sluggish to begin with.

Seems like a ton of turbo to run 8-10 psi.

Maybe you should rethink the entire setup.
 

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The converter will act much different under full power at the track.
I would throw some timing at it in the sluggish low rpm area and get it to the track before pulling it apart.
Having time slips, shift rpm drop, etc will make it MUCH easier for ptc to make educated adjustments, if needed.
^^What he said^^^ I have an run a PTC 9.5 on the street and it's a completely different animal on the track. The more power you throw at it the harder it locks up. Seems kinda loose on the street... Ignore it till you try it "max effort" at the track.
 

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I think we have 36 degrees of timing in it by 2,000 rpms.

So to be clear, i think everyone is telling me to forget about trying to get it to leave well on the street off idle? Like i said in the OP, the car will see 99% street use, so i'm not sure i care what it does off the brake/at the track once every couple years.

Am I going to ruin every bit of track worthiness by loosening this thing a bit? Is there a happy medium that will get me on boost faster off idle and still be fairly tight up top? My old converter was a 9.5" PI that was as tight as they could get it and it flashed at 6K on 8psi and i had no rpm drop between shifts LOL. Way more fun, but obviously correct for the application.

thanks for the replies everyone, i guess i have to think more about this.
If it didn't drop "any" RPM between shifts I think you are leaving ET on the table... JMHO.
 

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The converter isn't the issue. If you want quick spool and will be running a much lower power level than you built the car for, take off those 7675's and put on some 6262's or something that will spool immediately and still run mid 5's.

If you loosened the converter enough to do what your looking for on the street, it's not going to couple well. You will be throwing a lot of power out through the converter....when you throw power out with the converter, it turns into heat.
 

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Discussion Starter #13
Thanks everyone; I needed this intervention. You are all correct. I am being a giant pussy. I'll just take off my skirt and throw some power at it!
 
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