Contour Enthusiasts Group Archives Forums Modifications Duratec Performance IMRC Opening Point

For those who are interested in finding the optimal point when the secondaries open, check this out. I did three dyno runs with varying points of opening the IMRC.

1) 3200
2) 3500 (stock)
3) 3800

The results were surprising. Ford actually did their homework b/c 3500 gave me the greatest hp and tq under the curves. Opening it at different points does not improve performance and I do not recommend anyone to do this. If you are getting a chip burned, you may want to ask them not to touch the secondaries. Good luck and happy racing.

Thanks for the observations.

I expected that the stock 3500 rpm opening point was optimized. It should not come as a surprise that Ford did their homework - of course they did! Powertrain design and calibration really is more than throwing darts to make decisions.

-Kurt

Dyno chart pics?

How did you adjust your IMRC opening point?

Ford picked the point for emissions BTW.

On My Car 3800 would be way too late. 3500 (stock) is too late.
Even the 3200 with my chip is a bit late...

Guess Ford didn't expect people to play around with the point and Prove them wrong eh?

Great info! Demon perhaps your mods have altered the optimal point on your car?

My car feels like it opens at almost 4000 rom - sucks.
Gotta get your chip Demon!
WHo did you buy yours from cos I want your optimised program!!!!

Exactly my point. Why would you want it to be left where Ford put it for emissions and drivability? Especially when you could could have it where it would be optimal for your car. A chip's spark advance alone will make it worth dropping this point.

I'm still very interested in seeing the dyno charts and how he changed the IMRC opening points.

Originally bought it through SP (last summer - even sent my PCM - XGT1 in for Superchips to baseline & jumper) But I have sent it back 3 times for reburn since. (when all they cost were shipping :D)
I will be sending it in just once more. Custom spark curve, keep current fuel curve (I have S-AFC - so any future tunings are taken care of ), lower IMRC point (If I don't yank them altogether?), and raise redline.

Read my sig. I have almost every intake and exhaust mod - MAFS, KKM, headers, dual exhaust. I optimised my car by reflashing my PCM with a new program. My car was running way rich. I was running A/F ratio less than 10 over 4k rpm. We adjusted the opening point like I described. Ford did not only do it for emmissions. They set it where it maximized the power and torque under the curve. You simply make less power and torque if you move the opening point compared to a properly optimised setup at 3500rpm. I'm not trying to prove anyone wrong. You may feel different things in your butt dyno when it opens earlier, but dyno numbers don't lie. With everything EXACTLY the same, we moved the opening points and got worse results each time. If someone else can prove otherwise, by all means do so. For those who are not sure what to do, take my advice. The dyno does not lie. Good luck!

I still see no pics, dyno charts, flow graphs...

I still don't see how you changed the IMRC point. BTW - reflashing the PCM to a new code WILL NOT alter the IMRC point... Matter of fact it won't OPTIMIZE anything!!! Still same old crappy Ford code... :rolleyes:

I not being mean. I just want the proof and info I asked for...

Is that so hard?

Okay Demon. I will try to get the dyno graph you asked for. I hope the guy at the dyno saved it. I will post it and show you and all the non-believers the truth about the opening point. As for your comments, reflashing the PCM with a different program is the same as adding a chip. The programmer optimized the code (spark advance and A/F ratio) and then instead of plugging in a chip, he flashed my PCM with the new program. Hence, I don't have to worry about a chip coming loose. So it's not the same crappy code. It actually is a code that is better than Superchips and Diablo since it is custom burned for my exact setup. It gives me the perfect A/F ratio over the entire RPM range. That's why I can get 177hp out of a E0 SVT with a sound that's as close to stock as you could want. I will scan the dyno graphs in when I have the chance, but you have to be a little patient for them. Since you need to visually see the proof, then give me a week or two to get it to you. I'll post it either here or in the dyno section.