Converter help
 

I would like to know what physical size and stall torque converter you guys run. I have a 537 motor 264*- 270* @.050 700 lift 4.10 rear, 3700 lbs 69 firebird, t400 trans, 3500 converter. Only made one run down the 1/4 in the heat and it ran 1.52 60', 6.64 @ 105 1/8 mi and 10.37 @132 mph at the 1/4. I am ordering a new PTC converter but am unsettled on their recommendation because they started at an 8" then ended up going to a 10". I really don't want to have to pull this thing out several times. Peak torque is at 5400 rpm's, peak horsepower is at 6800 rpm's.

Steve

My ptc is a 10" 5500 rpm stall I think. They spec it for 540 cu in 3500 pounds and about 800 hp plus potential for a 200 shot. It rarely saw street miles but it wasn't particularly loose at part to low throttle.
In my opinion it may have been a tad tight but It probably was the cushion for the spray. I think they nailed it for my combo.
I agree on your wanting a 10. The slight et reduction from the weight diff. Is negligible at this level

I think they are trying to build mine to stall at about 4500-4800. I really want to run 9's with this pump gas combo.

Hopefully new converter will improve the 60 foot by a bunch.

My 10" from PTC goes to 4500. My brothers 8" goes 5300 and may be a bit loose for his combination.

The determined 4500 based on information I gave them from how the car was acting and the part numbers from my old converter that I tried behind my new motor.

If you have a dyno sheet, I think they can nail it really close. If not, they can get it pretty good, but you may have to try a couple times.

I have no reason to ever use anyone other than PTC based on my prior transactions with them. They have been awesome to deal with!

I have no reason to ever use anyone other than PTC based on my prior transactions with them. They have been awesome to deal with!

Thanks, I'm feeling better about this. I did send them a chassis dyno sheet and build specs. which I hope was helpful for them.

They started with an 8" then changed their mind to a 9" then called me back and final decision was a 10" with a 3500-3800 stall. I had just told them I was running a 3500 and wanted a 4500. As I said before, the torque peak was 541@5400 and HP was 631@ 6800 on a chassis dyno. I kind feel as though they were guessing.

X2 on PTC. We don't use anyone else for Custom converters. Like anything else, I have them build what I want for each individual combination. I don't rely much on the manufacturer's decision. I am mostly going by Engine dyno sheets and/ or just my own personal experience, not Chassis dynos as we don't really use them. However If those are your peaks, I wouldn't go with a 3,800 rpm converter either. A converter in your car will make all the difference in the world provided it still hooks after you put it in, also depending on how you plan on using it. If you set it up for optimum performance at the track but just cruise to the local Gas N' Sip then I would go right to 5,600-5,700. With more focus on street driving, I would back it off a bit, probably 1,000 rpm, and I would put that in a 9". Those are just rpm numbers mind to help get the engine in its power range where it needs to be to accelerate the car, but HOW it's built is just as important. There is a bit more to it, but I am sure you get the idea. Hope this helps. :2cents:

Steve,

With your set up I would recommend 10" converter from PTC part number PTC10TH10. This should be very close to what you need.

Dwight

Steve-my sons 434 pump gas ran almost the same numbers as your 537. His 60' was an aweful 1.60! 6.68@ 107 1/8th & 10.39 @ 132 in the 1/4. Was running only 3800-4000 10" converter. Bogged the motor way down! Called Scott from competition products. Gave him all our specs and dyno sheet. Got an 8" PTC with 5600 stall now. Told him Jake drives the car to school everyday. He said shouldn't be a problem. We want the 9 sec run also. We had other issues besides. I think we have corrected them all. We are looking for a 9.87-9.93 @ 137 mph run out of his car. We will know soon. Good luck!

Brian

Brian, how much does you sons car weigh?

Thanks for responding Dwight, do you think my car has potential for a 9 sec 1/4?

Steve

132 mph is enough for 9's yes! Get it launching hard and your there!

Give PTC ALL the correct info and your intentions and they will get it right.

They know what they are doing. And the fact they changed their mind, tells me they really discussed your combo.

3450# w/driver. It's full exhaust , full interior street car!

Brian

Steve- if your peak torque is 5400, that's around where the stall should be. Ours was 5600 peak torque & 6900 peak hp.

Brian

That thing is fast.

My car is very similar but 3700 lbs. still got full interior, power windows, power antenna and 4 mufflers. My buddy said it was one of the quietest cars going down the track.

Andy from PTC told me they discussed the combo. Got my fingers crossed.

Grandville, this is the one and only 1/4 mi. run with this new motor and it was in the heat of the day. If the car would have run a 10.60 I would not even consider a new converter and just have fun on the street but since I have a chance for a 9, then why not go for it.

Steve

X3 for PTC, I have three of their converters!