I went to test and tune today to try out my new 10", 2800 PTC tc. It worked well but did not give me the mph I got when I locked my PTS 9-11 tc. The best run I had today was 7.154 @ 96.83 with a 1.608 60' and I did not lock the tc. With my PTS 9-11 I ran 7.1x @ 99 mph when I locked it but only 94.5 mph when I did not lock it (same et). So it looks like I gained 2+ mph with the PTC over the 9-11 when not locked but I lost 2+ mph over the locked 9-11.
I had 600 rpm drop at gear shifts, the same as I did with the 9-11 when unlocked. When locked, the 9-11 would drop 1,000 rpm.
Attached is a screen shot at '0' mph. It shows the tc stalls a lot higher than 2800 and I could really build boost off the foot brake.
You are correct about the 1-2 shift being higher with the PTC. It shifts at 26 mph while the 9-11 shifted around 12 mph. I don't have any 1/4 mile tracks nearby.
Why is the stall so much higher than 2800?
I have 27" (255-60/15) MT ET Street drag radials.
1-2 shift was at 5460 and went to 4890. 2-3 shift was at 5522 and went to 4842.
Attached is another screen shot of same run.
I have 27" (255-60/15) MT ET Street drag radials.
1-2 shift was at 5460 and went to 4890. 2-3 shift was at 5522 and went to 4842.
Attached is another screen shot of same run.
I think you need some 28" tall tires to get that converter lugging down. I know when I take my 26" tires off and put my 28" with my weld wheels I can feel the engine staying in the powerband longer. But I dont have any track times yet with my 2800 10" so dont take my word as gospel.:redface:
I will be going in October....
Dusty--The tc seems fine as is. I really like how it drives on the street, especially at downshift. :biggrin: I hope to return to the track Thursday night for more test and tune.
Will the car respond better if the shift point is 200 rpm higher? Can I get there by removing weight from the governor? Thanks.
Dusty--The tc seems fine as is. I really like how it drives on the street, especially at downshift. :biggrin: I hope to return to the track Thursday night for more test and tune.
Will the car respond better if the shift point is 200 rpm higher? Can I get there by removing weight from the governor? Thanks.
You will almost always mph higher with a locked converter. He picked up a lot of efficiency unlocked with his 10" vs. the 9-11. Therefore the car can stay in 1st and 2nd longer and benefit from the better coupling efficiency the converter has vs the 9-11. Thats why he went faster with the unlocked 10" vs the locked 9-11. Id like to see the mph gain on a 5 disc vig vs my NL 9.5" PTC. I bet it wouldnt be more than 1 mph. Im slipping about 4.5% at 135mph. Im almost positive it would not e.t. as well with a 5 disc since they suck when unlocked. Giving up way too much in 1st where the car isnt moving fast yet. The 1-2 shift occurs at about 50 mph and the 2-3 is at about 87 mph in the car in my sig. This really helps the cars e.t.Two things
It seemed like you compared the unlocked PTC to the locked 9-11.
What psi are you running as that can affect shift rpm a little.
I had Jimmy trim a touch out of my governor and it went up about 150rpm so you can do small amounts if you are concerned.