Just wanted to share that I dyno tuned my racecar this weekend.
Big thanks to ATS racing for sharing thier thoughts on tuning the Power FC for the car. They were Spot On with what gains could be found tuning and my car runs better than EVER now. The mods are as follows: Wiseco Pistons, ATS valvesprings, fresh rebuild, very mild port blending on the exhaust side of the head, stock gen 3 motor, cams, injectors, etc. I built the motor myself, and it has proven to be working well so far. I have EBAY intercooler (XSPower), Megan Downpipe, short 2.5" exhaust, and autozone cone air filter. ECU is power FC.
This is a road race car and I had actually ran it in the 1/4 mile once before to a 12.1 @ 110 mph on 16 psi boost. NO tuning back then still on the POWER FC and commander.
I went to a local shop that let me have pretty much free reign with the dyno for 2 hours. HOYT dyno here in Lafayette, LA and they were very cool about us doing what we needed and were very helpful with what we needed. Logged Boost, wideband, and power (of course).
I ran a baseline at 227 whp and 245 wtq at 15 psi. I suspect this is what they were telling me at ATS with the computer being setup VERY conservative. It seems like it is setup for a bigger turbo or something as it is LEAN from 3-5,500 and VERY RICH (off the chart) after that. Seems like that would be a good baseline for something like TD06 20g or so. For the stock 20B, I would say that the stock ECU would probably make more power than the Power FC...though I did not confirm this.
Tuning session:
Anyway, I started tuning by running a dyno pull with the "map tracer" on. This allowed me to see what load cells I was runing in. I had made a few printouts of 20x20 cells just to be able to jot numbers down and highlight things. I noted how lean it was on the bottom end and how rich it was on the top end.
I started tuning by bumping timing and trimming fuel at the same time. I went 1 deg timing at a time (accross the board) and just stopped at 3 deg advance after a few pulls - timing makes a BIG difference in power.
For the fuel, You really need to change fuel by more than just a few "clicks" to see differences. I ended up looking at the 1.125 number and going 1.17x or so to see...I believe that would be something like a 5% difference over the cell you are looking at. I was looking at knock (at 3 deg advance I saw ONE spot that was a 8 count) and logging AFR's to see where I needed to change. Finally we got the top end back ON the chart (was more than 10.0 after 6200 rpms) and started getting the 3-5k rpms to an acceptable number.
We ended up 264.4 rwhp and 253.49 rwtq at 15-16 psi - A VERY IMPRESSIVE GAIN over where we started (some 38 rwhp).
Then we upped the boost to 18 psi. A few quick tunes in those cells resulted in 266 whp and 272.5 wtq. Thus showing that the CT20B starts running out of air on the top end. I know it would have made more and more tq had we pushed it, but I didn't feel like spending too much time in that range (since I never road race with it that high).
Anyway, thanks again to ATS racing who really would be a great source to get and tune a PowerFC. I think the computer works VERY well and was able to make these differences in 1.5 hours tuning it myself. This shows what a little research, a bit of money, a wideband, and a dyno can do for your car!
Patrick Harris
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