Vette(s): 1978 coupe in need of total restoration/modification
Hi,Ive got a 78 vette with the 190 hp 350 (L42?). I need more power to say the least. Ive got a set of vette L98 aluminium heads #10088113, 58cc, 1.94/1.5 valves. Question,will these heads help hp wise with maybe a Edelbrock intake and carb and also a mild cam? Doing a frame off rebuild on this vette with a real tight budget. Thanks,Frank
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
The problem is gonna be compression ratio...you need more, to actually make a noticeable difference. I don't know if installing the L98 head will do anything other than take some weight off the front. A small, torque cam, and intake will help, as would headers, but I don't think it's gonna be a fire breather without tearing into the short block. Others will chime in with different combos they have, and let ya know how their set-up works.
____________________________________ Joel Adams C3VR Lifetime Member #56 My Link
I also question the need for HP. Are you looking to peel the skin off your face going from 60 -100? or are you looking to smoke the tires and do jack rabbit takeoffs.
these are really two different things. You can build an engine for torque and you can build one for HP. Then of course is the comparison of trying to build an engine for peak torque or peak HP (which is good if you want to brag) but for real performance you want to optimize for are under the curve (which is for performance, not "measuring up")
Vette(s): 1979 Corvette, ZZ4 with serpentine belt front dress, ATI THM 350 with 3500 stall, Vette Brakes and Products suspension, tires - 295/50 rear 255/60 front on factory aluminum alloys, Autometer guages
The L98 heads are a very small combustion chamber. 58 or 64 CC depending on the application. This could create a problem with too high of a compression ratio. Also the limiting factor on the L98 heads is the flow numbers on the intake side. Even with a basic bowl blend and pocket porting they do not flow really high numbers. (<200 cfm) These are the same heads provided on the ZZ4 crate motors. The number one way to wake up a ZZ4 is to replace the heads. HOWEVER being that they are a corvette based part and make 350 HP all day long in the ZZ4 they could be used for a "mild" build. Seeing that 190 HP was stock for your car you would probably like 350 HP for a long while. Be aware that these heads are quite sensitive to detonation. Very little ping and you could destroy a good set really fast. Watch your ignition timing. Too much advance would be a killer. Also at 10:1 compression 91 or higher octane is required. If your block has been decked and you have the wrong choice in pistons you could have a static compression of over 12:1
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