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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 14,102
A/F ratios are A/F ratios.
If you can achieve 12.2:1 without a fuel head mod then all you are doing with the fuel head mod is wasting gas. There is no sustained boost on the street so the engine does not need to be fuel cooled.
Race cars and high HP engines are a different animal.

Optimally you should tune all 3 points of the WUR so an RPM switch is not needed. I would never presume that boost hits at the same RPM in every gear in every situation.

I think I've mentioned in the past that a friend - with absolutely stock internals; ie everything from stock P&Cs, 7.0 CR, stock 930 heads and manifold - but with cams, B&B headers, muffler, & stock K27 - achieved 360+ RWHP.
What boost level was that at? My engine, when dynoed in that same configuration, put out ~320RWHP @0.7bar boost.

Lots of apples and oranges here. The original post asked for formulas to achieve HP. There are many different ways to achieve the same HP levels, let alone varying degrees of power. Pat's SC engine lays down the same power as an early stock US 930 while Craig's monster CIS engine puts down more power than some of the EFI motors. Hell you could run a stock engine on toluene at 1.5bar and hit 400+HP (for a little while - ha!).
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 09-20-2007, 08:29 PM
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