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cole930 cole930 is offline
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Join Date: Mar 2000
Location: Auburn,In. U.S.A.
Posts: 2,449

From your previous post it is evident you need to do some self educating on 930's
before you go much further because this s=== gets real expensive real fast otherwise.

The 3.3 Turbo came stock with 7:! compression and under boost of .8 to 1.0 bar that compression ratio will easily become 11:1 to 13:1. Starting with an 8:1 compression ratio with no boost I can't even imagine what that compression ratio was at 1.5 bar, obviously enough to split a cylinder. At that compression ratio and 1.5 bar of boost there is no way you weren't also experiencing detonation unless you were running racing fuel and seriously retarded timing.

The factory put set specifications for these cars in the manuals, 26* of timing advance and timing retarded on boost, .8 bar wastegate springs, and a boost cutoff switch.They added those restrictions for one reason "they will blow up if you exceed them"

I did notice you have some of the needed mods to run a little more boost, larger IC. good exhaust, more fuel, etc. but 1 bar is still the most you should be attempting without race fuel, EFI, or WMI. And making sure the wastegate is working properly and the cutoff switch is hooked up are a must. Your biggest safety is your right foot, especially if you see the boost gage approaching 1 bar, if you see it going past 1.0 bar back off and if you wait to look at the telltale boost needle it's already too late.

Cole - 80 930 "The Old Sled"
Mods: TurboKraft Custom IC, 934 Headers, GSX 61, Zork, Port Work, SC Cams, Air Mod Fuel Dist Relocated, Water Meth Injection, BL WUR, MSD 6530, Greddy EBC, Synapse Bov, Short 2nd & 3rd with 8:37 R&P, Wevo Shifter, Coupling, and Mounts, MTX-L SSI-4, Big Brakes, Rebel Coilovers, Bilstein Sports.

Last edited by cole930; 08-16-2011 at 09:17 AM..
Old 08-16-2011, 09:08 AM
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