5.0L 305 LB9 comparison in Years
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From: Zephyrhills, FL. from Rochester, NY
5.0L 305 LB9 comparison in Years
I was looking a the Third Generation (1982 - 1992) Technical Data, and noticed that on my 89 Auto 305 TPI, the hp is 295 than 90 it goes up too 210hp on the same engine and tranny, whats up with dat!
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From: Manassas VA
Car: 04 GTO
Engine: LS1
Transmission: M12 T56
Re: 5.0L 305 LB9 comparison in Years
Originally posted by maverick544
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From: Manassas VA
Car: 04 GTO
Engine: LS1
Transmission: M12 T56
And the difference in the engine is the cams. Your 89 would have what's known as the peanut cam, complete junk. The 90-92 TPI cars all come with the L98 cam. The only way to get a good cam in the 87-89 305s was with the 5 spd and G92.
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From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
First its not 295 HP, its 195. 
The difference was the cam changes. The compression is all 9.3:1 for all years of 305 TPI, as far as I have seen. 89 MAF and 90-92 SD 305 TPI 5-speed with G92 is all rated at 230 HP, so the MAF -> SD switch gained nothing there. The 350's gained 5 HP from a piston change that increased compression about .5 points, from 9.3:1 to 9.75:1 or so.
The difference was the cam changes. The compression is all 9.3:1 for all years of 305 TPI, as far as I have seen. 89 MAF and 90-92 SD 305 TPI 5-speed with G92 is all rated at 230 HP, so the MAF -> SD switch gained nothing there. The 350's gained 5 HP from a piston change that increased compression about .5 points, from 9.3:1 to 9.75:1 or so. 
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