Hey all,
Here are the dyno sheets I promised. 2 motors dyno'd at the same dyno facility, but on different days. Both in IT trim. Butterflies removed from the intake manifold. Stock fuel pressure regulators, 15 deg BTDC. Both are run off the stock ecu. Both have 2.25" exhaust, S&S header, stock intake tube with filter off the MAF.
The red line is a junkyard motor that wasn't cracked open. The S&S header on this car was badly dented where it bends to go under the car. Exhaust wasn't the greatest work but flowed well i guess. Compression test was 175, 180, 175, 175. So, it was a very nice junkyard motor.
The blue line is actually a built motor. Shaved head, decked block (for the +.5 CR increase), valve job, new valves, pistons, balanced, etc. Goes to show it takes a lot to beat the factory numbers sometimes. Compression test was 180 across the board. We had dyno'd it with a JWT ecu also, but the peak numbers didn't change. There was an increase in power from 2k - 4500 rpm (which we don't use anyways) and after that it was the same as the stock ecu. With the JWT, after 5500 rpm the a/f dropped to 11.5:1, but the power was the same. Not optimal though so we'll have to see what that was from, possibly not from the ecu.
The built motor will be torn down, inspected and re-ringed over the winter and we are building 2 more motors, so we'll see what kind of numbers we get next season. Intake and exhaust setups are going to be changed dramatically. With the intake rule now changed it will be interesting to see if there is any gain to be had there. I would think so, but I'll wait for the dyno results to find out. We will also be custom tuning the ecu's so we'll see what gains we can get there.
So, who's next?
steve
edit: having problems with the server I was hosting it on. Attached is the file.
[attachmentid=152]