PDA

View Full Version : Dyno Numbers: 4R70W vs C4


kurt02gt
01-11-2008, 11:30 AM
I did the C4 swap and nothing else beside a retune. Everything else was the same.

Old 4R70W combo:
DirtyDog Performance 4000rpm stall Converter (reworked PI converter)
282rwhp and 304TQ (locked converter)

New PA C4:
DirtyDog Performance 5000rpm stall 8" converter
280rwhp and 367tq (no lockup)

The only thing I did different was the trans swap, no other mods. Both combos have 29 degrees of timing and a/f 12.7-12.9. Of course these TQ numbers are skewed by the TQ multi. and stall but I was really curious how efficient the converter would be being unlocked. It looks like it is very efficient which is what I was wanting.

The one weird thing was my rwhp peak increase from 6100rpm to 6500rpm. Not sure how the trans/converter swap would effect the peak rpm. Anyone know why?

Again dyno numbers means nothing on high stall converters, it is just a tuning tool but still wanted to share.
sixtyninemercury
01-11-2008, 01:47 PM
Again dyno numbers means nothing on high stall converters, it is just a tuning tool but still wanted to share.

How come you say that?
kurt02gt
01-11-2008, 02:10 PM
How come you say that?

because my motor not making 367tq but the converter multiplying will generate that number.
sixtyninemercury
01-11-2008, 03:36 PM
because my motor not making 367tq but the converter multiplying will generate that number.

With 1.58 sec 60' times and 11 quarter mile times - really???
RdRunnr
01-11-2008, 04:24 PM
How come you say that?

Dyno number on any car with a converter don't mean squat. The dyno is just a tool to dial the car in safely for automatic cars.
kurt02gt
01-11-2008, 05:04 PM
With 1.58 sec 60' times and 11 quarter mile times - really???

that was with the 4R70W and 4000rpm stall converter, footbraking and letting the computer control my shift points which was 6500rpm. That was with stock 2V heads, intake and stock 4V shortblock.

Now I have 5K stall with a brake and manual valvebody.:-)
kurt02gt
01-11-2008, 05:06 PM
Dyno number on any car with a converter don't mean squat. The dyno is just a tool to dial the car in safely for automatic cars.

I agree 100% but it did tell me that my C4 converter was efficent or the dyno numbers would of been alot lower.
sixtyninemercury
01-12-2008, 08:24 PM
Now I think that I understand what you guys are saying, thanks. :-)