Does Anyone Know Anything About the 1985 Corvette L98 Heads?
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Car: 1986 Camaro IROC Z
Engine: LB9 305 TPI
Transmission: 700R4
Does Anyone Know Anything About the 1985 Corvette L98 Heads?
How different are they from 1986 Camaro LB9 heads? I know they are both 58cc. I ask because I own an LB9 car but I can get a set of '85 Corvette heads for free.
Might be good just to practice and learn head porting on. Is there any real difference? I know 87 and later L98s were Aluminum.
Might be good just to practice and learn head porting on. Is there any real difference? I know 87 and later L98s were Aluminum.
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From: Orange, CA
Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
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Axle/Gears: 12 Bolt 3.73
Re: Does Anyone Know Anything About the 1985 Corvette L98 Heads?
How different are they from 1986 Camaro LB9 heads? I know they are both 58cc. I ask because I own an LB9 car but I can get a set of '85 Corvette heads for free.
Might be good just to practice and learn head porting on. Is there any real difference? I know 87 and later L98s were Aluminum.
Might be good just to practice and learn head porting on. Is there any real difference? I know 87 and later L98s were Aluminum.
462624.....75-86...350/400......76cc chamber, 1.72/1.5, 1.94/1.5 or 2.02/1.6 valves
I'll guess 1.94/1.5 IN/EX for a 350?
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Joined: May 2013
Posts: 604
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Car: 1986 Camaro IROC Z
Engine: LB9 305 TPI
Transmission: 700R4
Re: Does Anyone Know Anything About the 1985 Corvette L98 Heads?
From reading the Corvette forums, the L98 heads for 85 and 86 are different than the standard 350 heads from 75-86. I know they have 58cc chambers but so do the LB9 heads. I was wondering if anyone knows if they are the same as LB9 heads or different.
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Car: 89 Firebird
Engine: 355 TBI
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Re: Does Anyone Know Anything About the 1985 Corvette L98 Heads?
Mid 86 the Corvettes got the 58cc L98 heads. 85s had 76cc like DynoDon told you. Ive heard of people using the 58cc aluminum L98 heads on 305s but there are big differnces in them and the LB9 heads. Valve size and etc..
Re: Does Anyone Know Anything About the 1985 Corvette L98 Heads?
The larger bore of the L98 might allow for larger valves, and that could lead to clearance problems with the small bore of the 305. Even without actual mechanical interference, the shrouding could restrict flows. You'll determine that once you flip the heads and start measuring. It sounds like the '85 heads are not a good starting point, but getting the casting numbers would be critical to verify that.
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From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: Does Anyone Know Anything About the 1985 Corvette L98 Heads?
The larger bore of the L98 might allow for larger valves, and that could lead to clearance problems with the small bore of the 305. Even without actual mechanical interference, the shrouding could restrict flows. Youy'll determine that once you flip the heads and start measuring. It sounds like the '85 heads are not a good starting point, but getting the casting numbers would be critical to verify that.
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