93ND500

Do you all think that a 7730 ECM could be used to run a RamJet 502. I got a chance to get a RJ502 from a wrecked streetrod. The only thing is that there was a small fire from the accident and the harness/ECM burned up. I have an extra 7730 and harness sitting in the garage.......Think it will work

Grim Reaper

The 7730 can handle up to 8 Liters (488 ci), so it is darn close for displacement. It really depends on the HP level. The problem that happens is with large HP you start needing big injectors. The high impedence injectors used by the SD ECM can only go so big (36# I think). And then there is a second problem where the ECM can only shorten the pulse width so much which can affect idle.

Personally, I think you have nothing to loose to try it other than a little time and effort. Your definitely at the "outer limits" of the SD's ECM, but what do have to loose by trying.

afgun

Something that might work would be the <A HREF="http://para.noid.org/~lj/KRUD/KRUD.htm">KRUD Model 1 impedance converter</A>; this would allow you to run peak/hold injectors that you can get VERY big.

93ND500

Glenn91L98GTA, I thought about the injectors sizes too. But aren't those f**d 42/46# injectors high impedence units? I figured running them whith a moderate fuel pressure rate might get the job done.

93ND500

Well I picked up the 502 today....the motor really took a hit from that fire . The guy I got it from said he will refund my money if any of the major components are ruined. It's hard to tell right now if anything got messed up. The RamJet intake is completely chared black, with ALL the plastic pieces melted away. The distributor is a ball of goo. And the paint is gone, burned off, of most of the motor.

Hopefully it will clean up pretty good. It looks like the intake just needs to be bead blasted to remove the carbon. The rest of the motor I am going to go ahead and tear it down and do a rebuild. Wish me luck

Grim Reaper

Yes, I've noticed some larger injectors also but they start costing some $. My concern is still what is going to happen at idle as the injectors can only have so short of a PW.

I haven't looked at the link Afgun posted, but that may help.

Good luck on the 502. Hopefully you will be able to get the harness and various plastic parts fairly easily and nothing "warped".