Looking to see if there is an easy fix (not pulling motor) to stock compression and 8# boost. Would 64cc Trick Flows, or even bored out stock chambers, help reduce the compression enough to make it much safer to run 8 or more pounds of boost? Still not sure if I'm going meth or IC (maybe meth first because it's cheaper). What would the compression be with 64cc heads?

Hal

 

Still wont last long with the stock pistons, they dont like boost. There are alot of people that run 6-8psi for about a year or two before problems occur on stock motors tho.

Jay

 

No pistons like high hp detonation. I'll just have to set my advance low enough to compensate for 10.2 compression and 91 octane. I'm thinking about 27 degrees for anything over 4k rpm 100 map and only 5#. Or, bite the bullet and get the msd 5462 (boost sensitive timing) and set to 1 degree per pound of boost (or maybe more). Either way I'll do a couple WOT with my '95 and freescan to make sure knock is not happening. I only drive this car maybe 2k a year so even 20k is a long time.

Hal

Hal

 

out of all the people who run boost on a stock bottom end i would say 50% pop in the first 30 days or so. 25% within a yr and than there are the lucky/guys who really know what they are doing and have their setup last a few years.

If you get your compression down to 9.5.1 and run 6psi intercooled you should make it

 

About 9.5:1

 

At 62cc's you'll have approx. 9.7:1

I did make some assumptions on the following:

• Stock LT1 head gasket - 4.06" bore dia & 0.039" compressed thickness
• -5cc valve reliefs
• 0.035" in the hole

-Scott.

 

That could very well be true. To get 10.5:1 with a 54.4cc head you would need to assume compressed thickness of the LT1 head gasket to be about 0.050". A Felpro 1074 compresses to 0.039"

Too many assumptions

-Scott.

 

It's all in how conservative you are. On my first venture into supercharging, 5# non-IC powerdyne, it lasted over a year until the supercharger went. I had a BTM set to about 1.5 degrees per # and used the fmu with svo 24lbs and Freescanned it to make sure knock wasn't a problem.

This time I'm going 5# non-IC (at first, planning on changing this to FMIC soon and upping boost to 7#) with 48lb injectors, 1.5 retard per #, and fmu. This time around I'm using a DynoJet Wideband to check the AFR. Should be as safe as things can get.

As we all know, knock is your biggest enemy. Any engine can distroyed by it. Keep that out and it shouldn't be too great a feat to get a lot of miles out of a setup.

Hal

 

Good luck, honestly is there a member on the board that has had a stock SC lt-1 last over 2 years on pump gas and dailey driver? Non IC and no knock will be nearly impossible on 91, with meth no problem... You could save a lot of money and time going other ways IMO..

 

OK, the 91 octane part does sound bad. I'll add meth. I'm not so sure I can get a 400 hp NA engine to pass CA smog, that's why I'm going this way.

Hal

 

water/meth combo

 

It can be done, at worst run Denatured Alcohol when you take the test, thats what my buddies do and it works here in Colorado (STRICT E-TEST).. 400 crank hp could be done easy, 400 to 500 rwhp could be done very easy with small shot of gas, medium cam, and good heads at half tyhe price of a FI setup..... I would post in the NA section largest haeds/cam for Cali SMOG test, there are plenty of fast F-bods from Cali and SMOG compliant..