My god. Please put the keyboard down and go to a track to get real life data. Op......you have a high 11 second car as it sits
Dude, just look at the guy's 60 ft times. He's running 1.8x-1.9x 60s. That's what I was running on street tires in a wrong wheel drive turd with a much lower power/weight ratio. His trap speed is 117 mph, probably blowing through the converter, which is good for mid to low 11s if he can get the car to 60ft down in the 1.4x-1.5x range like it should.
As it sits... it's probably tapped out in the low 12s. It needs a properly matched converter and valve body with the nitrous spraying off the line if it's going to improve.
As for going to the track, what were you doing this past weekend? I was HoH with this car (co-worker's car) getting the bugs worked out on the new AED carb.
434ci SBC, 13.8:1 compression, ported Brodix heads, solid roller cam with 276/282 @ .050" and .720/.725" lift, recently switched to E85 to make it more consistent and getting the kinks worked out. Has a TH400 with a pro-torque 5500 stall. Race weight is 2,210 lbs (per the scales at HoH) with him in it and a full 5 gallon fuel cell. Tube chassis car with lexan windows and fiberglass front end, hood, fenders, doors, and trunk. It's stupid how light that thing is. We started the day Saturday running 5.44 @ 124 and after a few jet and plug changes, managed to get a 5.28 @ 128. (1/8th mile bracket car) It has much more in it. The best pass on Sunoco 112 was 5.22 @ 130 mph. 60ft was consistent in the 1.16-1.18 range.
We'll be out with it tonight when the Outlaws come out to HoH. See you at the track!
---------- Post added at 10:44 AM ---------- Previous post was at 10:33 AM ----------
40 hp is worth 1 second?
---------- Post added at 08:33 AM ---------- Previous post was at 08:32 AM ----------
If my converter wasn't a nitrous converter, I'd bet it'd go a 10.7, and I'm running a 3.73 because it ran out of gear with 4.10s on the bottle.
---------- Post added at 08:34 AM ---------- Previous post was at 08:33 AM ----------
But if you think 384 is a accurate number, you're crazy
Herein lies the issue with this whole discussion. Chassis dyno numbers don't matter with a converter.
Exactly. You can't use chassis dyno numbers with an auto because the dyno can't read the converter. The chassis dyno reads the torque put out at the rear wheels which after going through all the gears ends up being well into the thousands. It then does an algorithm comparing wheel/roller speed with engine rpm to determine the overall gear ratio between the engine and the rollers so it can reverse calculate the torque figure to an estimated torque output at the engine minus drivetrain losses. With a torque converter that raises the engine rpm (slip), the dyno can't see the difference between the converter slipping and a steeper gear. Therefore, the converter output ends up being ignored or cancelled out in the dyno's algorithm. So all the dyno shows is drivetrain loss plus efficiency loss at the converter. It's not seeing the torque being multiplied by the converter.
When I did my calculations, used the dyno curve to estimate a more realistic torque output from the converter with an ideal converter build. The average torque difference ends up being roughly 15% higher across the run.
If you've wondered why an auto puts down less power on the dyno compared to a manual but walks away from the manual at the track, this is why. This is also why I asked if the OP's converter was locked out on the dyno as that would take the converter slip out of the equation.