Procharger on stock 502 MPI???
 

I recently acquired a 98 Baja 272 Boss. Has a 502 MPI engine and a procharger with intercooler. I am fairly certain that the previous owner simply bolted this thing on. No lower compression forged pistons, no cam change, nada. I was told that it only makes about 3psi of boost, but I really don't want to have to replace an engine. I plan to just remove it and restore everything to stock unless someone here tells me otherwise...

Any thoughts?

Thanks for reading!

Dustin

The 502 internals are forged and can handle the job. the issue with PCing them is the system setup. If the fuel pressure has been set up right along with a good ECU re-calc then you might be in good shape. If those things have not been addressed you are likely asking for problems.

Thanks Scarabman. After reading and looking some more at the boat, I can verify that there is an aftermarket fuel pressure reg. No idea if there is a high volume pump or if the ECM was worked. In my opinion several things were done half assed - which made me wonder if it was just thrown on or actually done right...

Thanks for the reply and I will see what I can find on the other stuff. Still isn't running (no fuel) but does fire up on starting fluid.

Some of the PC kits came with an aftermarket fuel pressure regulator that was used to make the motor run richer to accommodate the boost. PC would claim that is all that is needed for proper set up, which is not true. In a lot of cases it caused to much fuel to be added and wash down cylinder walls and then cause blow by. Crank case pressures in some cases get so high that dipsticks would get pushed up out of their tubes. I would also be skeptical of the system being set up for 3 pounds of boost. It is more likely 5-7. Pulley size dictates as well as rpm since it is a centrifugal system. Investigating the ECU mapping will be key. If it is done right,the PC boosted motor will put you back in your seat. The other thing worth noting is that it would appear yours in one of the older style huffers that shared their oil with the motor. If it grenades, and they do, it will put shrapnel in your motor. The newer style units are self contained oiling.

Scarabman - you sure seem to know a lot about PC's! Everything you said makes complete sense and this thing is coming off! Guess the only thing would be where to locate an original regulator, crank pulley and air cleaner ;-) And anything else that got removed...

fixx
 

i would leavr it on their,,you donk know if the ecm was remaped and if it was thats another 300-600 to get it rite again..i know many guys running them for years with no issues including me....i also have the old style pc on both my motors aand i have a vary fine screen on the discharge oil line and the feeder line comes off a oil filter..a 272 is a heavy boat ant it needs all the power it can get..

i agree with fixx,a small pc on a 502 with 3 or 4 lbs boost can really wake that engine up,if it runs good,leave it on and enjoy,make sure you use premium fuel.

To be clear, I was not advocating removing the system. I was pointing out things to look at/investigate so that the system can be setup properly. I ran a PC'd engine for several years with pretty good success.....after all the kinks from the original install were corrected.

That being said, if you feel like you should remove it and your primary goal is reliability/piece of mind, you are better off without it.

Let me know if you want to sell that ProCharger.

I've got a friend that's been running a SC on a 502MPI for several years now. Stock internals with a lot of hours. No problems so far... knock on wood.


If you were that worried about the SC system, I would have kept looking at other boats. ;)