Jeep Grand Cherokee Forum banner
1 - 14 of 14 Posts
If you were going to toss the bucks into the supercharger, then look towards a good headered exhaust, possibly some replacement cam and port work.
Won't be exactly the same, but then again it won't be a slouch either.
Depending on your application, there's quite a few options.
 
to answer the question, "can it be done" yes, anything can be done, but cost is a factor.

if you are worried about compression, slap a thicker head gasket on there that will solve that problem.
 
You can super-charge the thing no problem :lol:

This is coming from a guy with a low compression 4.0 I6 that's more into gearing than power :lol:

I might give a call to the super-charger company and ask them about it. Most superchargers only pump 6 or less PSI into the motor so I'm pretty sure even the HO motor would be ok without "race" octane gas.
 
Doctor Evil said:
just an old mechanic buddy of mine. he says by increasing the space between the head and the block it can lower the compression low enough to supercharge (in most cases)
Yes, it can be done that way but sometimes it can work against you.
Incereasing the distance between the piston and the deck of the head leans towards an engine that's more detonation sensitive.
If anyone could shortcut it would be the factory, but when they juggle engine compression ratios they do it through different pistons or different version heads rather than call their gasket supplier for a different thickness stack.
So yes, it can be done but just be careful.
If you wanted to check on different thickness gaskets then I'd say to check with Cometic. Their gaskets are multi layer and can be built in varying thicknesses for compression juggling.
 
AMC_Racer said:
I wouldn't see it being safe to try with an advertised compression ratio of 9.7.
I feel that you're stuck trying to improve performance in more conventional methods.
The 96 - 98 Mustang Cobra runs a 32 valve engine 4.6L aluminum block, hyperutectic pistons with 9.85:1 compression. I have read of guys running as much as 14 psi blowers at the track with nothing more than a custom chip made for it.

You should be able to run a 6 - 8 psi blower / supercharger with no ill effects on the motor. Just make sure to get a custom chip made for the computer. You will need to open up the intake and the exhaust in order to let the engine breathe properly.
 
Hey................Kenne Bell makes a supercharger for the 4.7!! I wish I had the bux to even consider. I would love to make my WJ as fast as my 383 sbc. Give him a shout (or @ least his company). Good luck and lucky you :smile:
 
1 - 14 of 14 Posts