chucky wrote:i may be wrong but the pgm 4 is heavily restricted thats why a pgm 3 was used. i dont think you will have any where near **** 72 bhp more like 40 bhp, mc 28s are known to be heavily restricted and hard/ expenive to de-restrict.
im not a expert on mc 28 de-restricting but i think you will be dissapionted the mc 21 flywheel is a great idea but i think the pgm 4 restricts powervavle opening and retards the ignition in 4th,5th and 6th

You were right that you may be wrong!

An mc21 flywheel will make a noticeable improvement but a hrc card is the way to go.

I for one would love to see dyno print outs on the same dyno with the pgm3, and the pgm4 with the offset key or 21 flywheel and then the hrc card. Yes the pgm4 with flywheel will be the lowest, no where near 40bhp though, I think hrc card will be the best.