LG4 compression
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Car: 1986 IROC
Engine: 305 going to 355
Transmission: 700R4
LG4 compression
In the new Tech Data section under engine specs it says my compression ratio is 9.5:1 in my 1986 LG4 305. I thought it was more like 8.0-8.5:1. Is the Tech data correct? It also says that I have 165 horsepower when I have seen other articles saying it is 145hp. What do I have?
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1986 IROC LG4 "Bone Stock" (for now)
[This message has been edited by wiggy'sIROC (edited January 30, 2001).]
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1986 IROC LG4 "Bone Stock" (for now)
[This message has been edited by wiggy'sIROC (edited January 30, 2001).]
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
That's consistent with other things I've heard and my experience with trying to advance the timing above factory setting - pinged quite a bit at 6 degrees, requiring midgrade to correct. Apparently they went with flattops across the board on LG4's and L69's in '86. The lower numbers you quoted were for earlier LG4's.
Now, if someone can explain why your IROC is rated at 165 hp, and my sport coupe at 155, I'd be interested in hearing that. I know L69's had dual snorkle intake, different secondary rods & hangers, and better flowing exhaust.
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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/LB9 block, ZZ3 cam and intake, WP 305 heads ported & polished, Hooker headers & y-pipe, hi-flow cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.
Now, if someone can explain why your IROC is rated at 165 hp, and my sport coupe at 155, I'd be interested in hearing that. I know L69's had dual snorkle intake, different secondary rods & hangers, and better flowing exhaust.
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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/LB9 block, ZZ3 cam and intake, WP 305 heads ported & polished, Hooker headers & y-pipe, hi-flow cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.
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