Converter too tight??
04-25-2015, 09:54 AM
#42
Too tight if you're leaving it at 12-13lbs IMO. I liked my 9.5 PTC 17-0 at low boost. The RPM curve almost flat lined at 25lbs though. Could barely see the shift. Came up on the converter really fast though, great 9 sec street converter.
Last edited by Forcefed86; 04-25-2015 at 12:03 PM.
04-25-2015, 10:17 PM
#44
You have to go into a datalog and hit "tools" - "create math channel" and make whatever you want up. I created a MPG, converter slip and hp. I have to figure out a math channel to account for the water/meth as that is being consumed also.
04-26-2015, 11:38 AM
#46
Ok, been kicking this things a$$ with 16-17-18psi and she hasn't missed a beat 
. Converter slip appears to be unchanged. But, this is from a slow roll in 1st and ~6200 rpm shift points. Hard to believe how this sucker tightens up - its amazing.
1st-2nd: 6200 to 4688 = 1505 drop
2nd-3rd: 6372 to 5052 = 1320 drop
Do you guys find this acceptable or still too much?
. Converter slip appears to be unchanged. But, this is from a slow roll in 1st and ~6200 rpm shift points. Hard to believe how this sucker tightens up - its amazing.1st-2nd: 6200 to 4688 = 1505 drop
2nd-3rd: 6372 to 5052 = 1320 drop
Do you guys find this acceptable or still too much?
04-26-2015, 02:40 PM
#47
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What's your math and inputs for converter slip? The area you have selected shows 33 for slip, that's not percentage is it? Cause no way a converter slipping that much would drop that much on shifts, and slip should go up as you go in higher gears, ex. If you went from 3.73 gears to 2.73 you would get more slip.
04-26-2015, 06:51 PM
#48
What's your math and inputs for converter slip? The area you have selected shows 33 for slip, that's not percentage is it? Cause no way a converter slipping that much would drop that much on shifts, and slip should go up as you go in higher gears, ex. If you went from 3.73 gears to 2.73 you would get more slip.
You need an actual speed input (I pick up speed from the front wheel)
As far as I u/s, you really only measure slip at the end of a quarter mile, so the end of this log slip is 7%. This wasnt quite a quarter mile so its right on.
Track day I was showing 4-5%.
05-29-2015, 03:23 PM
#49
We'll, pulled the converter and sent it back to PTC to slightly loosened it up. I have to hand to those guys (so far), the are restalling it for free I just pay the freight. They normally allow 30 days but cut me some slack as I really just got the car out. Quite honestly, if they would of charged me to restall it I would of put the thing on a shelf and ran the looser Trans Specialties $425 converter and been done. $50.00 shipping ea way + the restall fee on top of a 1000.00 is too rich for my blood.
05-30-2015, 12:45 AM
#53
I'm running a new PTC as well.
My finish line rpm dropped from 6900 to 6200.
My little turd likes to rev.
2-3 drop is 1300 rpm if I shift at 6700.
Dusty suggested loosening by 400 rpm.
Here is what is interesting comparing my old ATI 9" to the new PTC. Logs are very revealing,
At 6000 in high gear, the old converter had the car going 103 mph. On the order of 28% slip.
By 6900 rpm at the finish line, 145 mph and 11% slip.
The PTC at the same 6000 in high gear was 138 mph.
Looking at the logs, the PTC really couples hard past 5200.
My ATI 9" btw was designed in 05 for my NA 496. And it was $950.
Of course you might think, well, just crank the boost up 5 psi.....
But that isn't in the cards for me yet.
Looking forward to the 400 rpm, I'll be able to leave harder too.
Ron
My finish line rpm dropped from 6900 to 6200.
My little turd likes to rev.
2-3 drop is 1300 rpm if I shift at 6700.
Dusty suggested loosening by 400 rpm.
Here is what is interesting comparing my old ATI 9" to the new PTC. Logs are very revealing,
At 6000 in high gear, the old converter had the car going 103 mph. On the order of 28% slip.
By 6900 rpm at the finish line, 145 mph and 11% slip.
The PTC at the same 6000 in high gear was 138 mph.
Looking at the logs, the PTC really couples hard past 5200.
My ATI 9" btw was designed in 05 for my NA 496. And it was $950.
Of course you might think, well, just crank the boost up 5 psi.....
But that isn't in the cards for me yet.
Looking forward to the 400 rpm, I'll be able to leave harder too.
Ron
05-30-2015, 05:25 AM
#55
I'm running a new PTC as well.
My finish line rpm dropped from 6900 to 6200.
My little turd likes to rev.
2-3 drop is 1300 rpm if I shift at 6700.
Dusty suggested loosening by 400 rpm.
Here is what is interesting comparing my old ATI 9" to the new PTC. Logs are very revealing,
At 6000 in high gear, the old converter had the car going 103 mph. On the order of 28% slip.
By 6900 rpm at the finish line, 145 mph and 11% slip.
The PTC at the same 6000 in high gear was 138 mph.
Looking at the logs, the PTC really couples hard past 5200.
My ATI 9" btw was designed in 05 for my NA 496. And it was $950.
Of course you might think, well, just crank the boost up 5 psi.....
But that isn't in the cards for me yet.
Looking forward to the 400 rpm, I'll be able to leave harder too.
Ron
My finish line rpm dropped from 6900 to 6200.
My little turd likes to rev.
2-3 drop is 1300 rpm if I shift at 6700.
Dusty suggested loosening by 400 rpm.
Here is what is interesting comparing my old ATI 9" to the new PTC. Logs are very revealing,
At 6000 in high gear, the old converter had the car going 103 mph. On the order of 28% slip.
By 6900 rpm at the finish line, 145 mph and 11% slip.
The PTC at the same 6000 in high gear was 138 mph.
Looking at the logs, the PTC really couples hard past 5200.
My ATI 9" btw was designed in 05 for my NA 496. And it was $950.
Of course you might think, well, just crank the boost up 5 psi.....
But that isn't in the cards for me yet.
Looking forward to the 400 rpm, I'll be able to leave harder too.
Ron
06-25-2015, 01:07 PM
#56
OK, converter is back and installed. Went from a 15 stator to a 16. I can get to about 3k before the wheels break loose, before it was around 2650. My brakes aren't great so that's about it. On the 2 step I can get around 7.5psi, probably about the same as before. I can probably get that higher if I raise the limiter a bit (set to 2650) now that she'll go to 3k.
But, the 2-3rd shift is still a 1200 rpm drop
. So it looks like it was loosened by about 100 rpm up top. Will have to drive it for a while to see what I think about it, but it probably coming out for a locally built unit. I want a ~700 rpm drop.
This was at 16-17 psi. Not sure what 12-13psi will look like...probably tighter??
But, the 2-3rd shift is still a 1200 rpm drop
. So it looks like it was loosened by about 100 rpm up top. Will have to drive it for a while to see what I think about it, but it probably coming out for a locally built unit. I want a ~700 rpm drop.This was at 16-17 psi. Not sure what 12-13psi will look like...probably tighter??
06-25-2015, 02:37 PM
#58
Yup It’ll get tighter… more power = more slip.
Why are you targeting a 700rpm drop on the shifts? IMO you should be more concerned with as little slip up top as possible while maintaining the ability to slip enough off the line to get the turbo lit. Sounds like your current unit does that? Or are you wanting more off the line? Get that brake pedal extension welded on and get some leverage on those brakes. Sounds like you’re brake system isn’t setup to hold power on a cold stationary disc.
Usually customers exaggerate their engines power level. Then when PTC specs a converter it’s too tight because the owners aren’t really making the claimed power. Not making any claims towards you personally, that’s just what Dusty told me when he spec’d my 17 blade 9.5 originally. I told him 750 at the crank.
Did PTC suggest the 16 blade? I’m surprised they would go from a 15 to a 16 if you told them you wanted 700rpm drop between shifts. If you take it out again, it’s cheaper to just have it re-stalled. You know what a 1 blade drop is worth on your combo now. If you go with a new converter you are back at square one guessing.
Why are you targeting a 700rpm drop on the shifts? IMO you should be more concerned with as little slip up top as possible while maintaining the ability to slip enough off the line to get the turbo lit. Sounds like your current unit does that? Or are you wanting more off the line? Get that brake pedal extension welded on and get some leverage on those brakes. Sounds like you’re brake system isn’t setup to hold power on a cold stationary disc.
Usually customers exaggerate their engines power level. Then when PTC specs a converter it’s too tight because the owners aren’t really making the claimed power. Not making any claims towards you personally, that’s just what Dusty told me when he spec’d my 17 blade 9.5 originally. I told him 750 at the crank.
Did PTC suggest the 16 blade? I’m surprised they would go from a 15 to a 16 if you told them you wanted 700rpm drop between shifts. If you take it out again, it’s cheaper to just have it re-stalled. You know what a 1 blade drop is worth on your combo now. If you go with a new converter you are back at square one guessing.
06-26-2015, 07:03 AM
#59
Yup It’ll get tighter… more power = more slip.
Why are you targeting a 700rpm drop on the shifts? IMO you should be more concerned with as little slip up top as possible while maintaining the ability to slip enough off the line to get the turbo lit. Sounds like your current unit does that? Or are you wanting more off the line? Get that brake pedal extension welded on and get some leverage on those brakes. Sounds like you’re brake system isn’t setup to hold power on a cold stationary disc.
Usually customers exaggerate their engines power level. Then when PTC specs a converter it’s too tight because the owners aren’t really making the claimed power. Not making any claims towards you personally, that’s just what Dusty told me when he spec’d my 17 blade 9.5 originally. I told him 750 at the crank.
Did PTC suggest the 16 blade? I’m surprised they would go from a 15 to a 16 if you told them you wanted 700rpm drop between shifts. If you take it out again, it’s cheaper to just have it re-stalled. You know what a 1 blade drop is worth on your combo now. If you go with a new converter you are back at square one guessing.
Why are you targeting a 700rpm drop on the shifts? IMO you should be more concerned with as little slip up top as possible while maintaining the ability to slip enough off the line to get the turbo lit. Sounds like your current unit does that? Or are you wanting more off the line? Get that brake pedal extension welded on and get some leverage on those brakes. Sounds like you’re brake system isn’t setup to hold power on a cold stationary disc.
Usually customers exaggerate their engines power level. Then when PTC specs a converter it’s too tight because the owners aren’t really making the claimed power. Not making any claims towards you personally, that’s just what Dusty told me when he spec’d my 17 blade 9.5 originally. I told him 750 at the crank.
Did PTC suggest the 16 blade? I’m surprised they would go from a 15 to a 16 if you told them you wanted 700rpm drop between shifts. If you take it out again, it’s cheaper to just have it re-stalled. You know what a 1 blade drop is worth on your combo now. If you go with a new converter you are back at square one guessing.
One thing that I get hung-up on is that fuel consumption is lower in high gear vs 2nd gear with this converter. Is this normal? I would think fuel usage should be higher in high gear. Maybe this is OK but I just associate power w/fuel used.
06-26-2015, 08:56 AM
#60
I’d guess you’re seeing a ton less RPM with the tighter converter in 3rd.? Have you run 3rd out to the same RPM you take 2nd ?
I think that is the nature of the beast as far as RPM drop on the 9.5 PTC conv. They tend to couple hard around 300feet out and require a lot of power. Where other converters would still be slipping 25-30%. I haven’t really decided if this is a good thing for moderate power setups. It gives you a nice tight converter on the big end, but it doesn’t slip and multiply torque like crazy through the 1/8th like a yank converter (or similar). I really think your converter needs more power to work correctly. If you don’t want to add the power, they are easy to sell! Get a yank SC3000 would be cool to see a direct comparison…
Stock 48 is seeing around 10% slip uptop. I see under 5% with the PTC. And we all see which nets the best ET!
I think that is the nature of the beast as far as RPM drop on the 9.5 PTC conv. They tend to couple hard around 300feet out and require a lot of power. Where other converters would still be slipping 25-30%. I haven’t really decided if this is a good thing for moderate power setups. It gives you a nice tight converter on the big end, but it doesn’t slip and multiply torque like crazy through the 1/8th like a yank converter (or similar). I really think your converter needs more power to work correctly. If you don’t want to add the power, they are easy to sell! Get a yank SC3000 would be cool to see a direct comparison…
Stock 48 is seeing around 10% slip uptop. I see under 5% with the PTC. And we all see which nets the best ET!