Converter too tight??
#61
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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…
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Funny thing is, theres a guy on YB that has a sig that says "you don't make enough power for a PTC"...lol...there is some truth to that!!!
I too am out on a fence as to whether or not for a MODERATE setup a tight converter may not be ideal. It was actually something that I had concerns about going in.
#64
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Just got mine back and in as well. I'm working with Dusty.
Mine was a 16, now an 18.
Feels excellent on the street. Hovers around 2200 with normal driving.
Foot takes nicely to 3500. Before it was trying to spin at 3400.
I prob did not have enough power or too light a car for the prev 16 unit. I lost 800 rpm at the finish line, and the car slowed 3 mph.
Will be awhile before I can get to the track.
Mine was a 16, now an 18.
Feels excellent on the street. Hovers around 2200 with normal driving.
Foot takes nicely to 3500. Before it was trying to spin at 3400.
I prob did not have enough power or too light a car for the prev 16 unit. I lost 800 rpm at the finish line, and the car slowed 3 mph.
Will be awhile before I can get to the track.
#71
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Same setup Shifting at 6600 and turning the boost up to 25 resulted in a noticeable 900-1000 rpm drop at the shift. Trapping 153.
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Few months old but a lot of good info here!
I'm curious what the second number does on these converter specs. For intsance 17-0 or 18-35.... What does the second number do? I know its reference to fin angle but how does it correlate to the way it responds.
I have a 14-35 PTC that I basically told them I wanted it to be as tight as possibly driving around.... They never told me I needed to .make 1000+rwhp but that's besides the point.
I'm getting around to restall it but with a 370 and billet s480 on 12-15psi (assuming 800whp) dam thing was dropping 1700-1800rpm shifting at 6600 and felt like it had no *****. Long story short I blew the motor and I'm doing a gen 4 SBE and plan to make a true 750-800rwhp. He is suggesting a 16-45..... I don't know but reading everything I have read so far I think it will still be too tight.
I'd really like to just sell the PTC and get a PY3400 since that thing multiplies torque so well.
On a side note I went 135mph with the budget PTC 10' converter shifting at 6400 I had a 900RPM shift drop and that thing felt amazing! If they could make this 9.5 just a touch tighter than the budget 10' they sell I would be golden!
I'm curious what the second number does on these converter specs. For intsance 17-0 or 18-35.... What does the second number do? I know its reference to fin angle but how does it correlate to the way it responds.
I have a 14-35 PTC that I basically told them I wanted it to be as tight as possibly driving around.... They never told me I needed to .make 1000+rwhp but that's besides the point.
I'm getting around to restall it but with a 370 and billet s480 on 12-15psi (assuming 800whp) dam thing was dropping 1700-1800rpm shifting at 6600 and felt like it had no *****. Long story short I blew the motor and I'm doing a gen 4 SBE and plan to make a true 750-800rwhp. He is suggesting a 16-45..... I don't know but reading everything I have read so far I think it will still be too tight.
I'd really like to just sell the PTC and get a PY3400 since that thing multiplies torque so well.
On a side note I went 135mph with the budget PTC 10' converter shifting at 6400 I had a 900RPM shift drop and that thing felt amazing! If they could make this 9.5 just a touch tighter than the budget 10' they sell I would be golden!
#74
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from what I see the race 9.5 can be made tighter than the 10" . I have a 10" ptc and I sent it back to ptc and told them to tighten it up upstairs and it works good. I can get 3200 pretty easy and it is nice and tight by 5500 rpm. mine is a 10"ths-200*degree fin angle-ported stator -spragless.
a touch tight for my 10# boost but the more I turn it up the better it works. my gut feeling is a t 15# boost it will be perfect. but I need better traction first.
a touch tight for my 10# boost but the more I turn it up the better it works. my gut feeling is a t 15# boost it will be perfect. but I need better traction first.
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over 1700 on both 1-2 ad 2-3. car felt like a turd and this is a 370 and billet 80mm. only went 130mph at 12-14psi. hell my 5.3 cast s475 went 135+ on 14-15psi. converter was way too tight.
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My she 5.3 with JFR 215/215 112* can and box stock s475/83 @ 14psi went 135 being super fat .