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443 Views 4 Replies 4 Participants Last post by  chansigril
I asked about the tranny durability and such... but what about the engine's? I read that on turbo charging a base or sl, its only safe to run the it at 6psi. And the s/c boosts to 9-11? How would I go about boosting it that high safely? And not put too much wear on the engine etc. Thanks again.
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upping the boost

I read on another post that in order to up the boost we need to drop the compression on our engine. i.e. We run at 11:1 and we need to run something like 8:1 to up the boost to 11 or 12 lbs for the supercharger. The only way I have read to drop the compression is with new pistons and rods. Hope this helps.
Cool, so pistons and rods... we would also need fuel injectors..upgraded fuel system, what else would we need to run 10-12 psi off the supercharger safely and reliably?
Re: upping the boost

943KGT said:
I read on another post that in order to up the boost we need to drop the compression on our engine. i.e. We run at 11:1 and we need to run something like 8:1 to up the boost to 11 or 12 lbs for the supercharger. The only way I have read to drop the compression is with new pistons and rods. Hope this helps.
Stock N/A motors run at a little less then 10:1

If you want to run forced induction I would suggest running 8.5:1 compression pistons. And you dont have to change the rods, there fully capeable of handleing the power.

If you have to change anything it would be the crank, most N/A cranks are cast not forged and cant handle the power. The fule system depends on horsepower also.
hollywood pretty much has it. i don't know that you need a forged crank tho it certainly wouldn't hurt. interestingly some na did come with a forged crank, can't remember the details tho, just had a discussion about this a few days ago too while installing my catch-can. too... much... information... :D

at any rate, you will have to change your compression ratio as well as your fuel delivery. in order to run it safely you should have the appropriate gauges to monitor egt (front/rear), a/f, fuel pressure and boost. an intercooler or coolers certainly wouldn't hurt either. now this is assuming that you have done the prep work to open up the flow (intake/exhaust) and can already change the a/f values via afc. for further maximization you should perhaps investigate cams and timing. alright, i'm getting carried away but this is basically my plan of attack after a great many conversations regarding your question... can you tell where i'm headed? alright, well hope this helps, safe travels.

- mike
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