new to HR cams, have questions
08-22-2002, 05:12 PM
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Car: Pontiac Grand Prix GTP
Engine: 3.8L V6 SuperCharged
new to HR cams, have questions
well the first one is actually about my afr guideplates. how do you make sure they are installed straight? They move around a great deal when the rocker studs are not tight, and I don't want to just "eyeball" it.
the next question is this:
I bought a zz4 shortblock and I will be putting my afr 190's on it with a magnum 270HR cam, RPM air gap intake and no emissions equipment. I am getting the #875-16 lifters, #3136 timing set, #7940-16 pushrods, 1.6 magnum roller rockers, and the #08-1000 roller lifter install kit (all from COMP Cams). what other odds and ends do I need to find? Can I reuse the timing cover from my non-roller cam motor? Do I need a thrust button? The afr springs are good for .550 lift and with the 1.6 rockers I will have .533 lift. Is that enough room for error? Should I get a rev kit or a stud girdle (I've been known to abuse my motors)?
This is a weekend only street/strip car that will see at most 6000-6250 rpms.
the next question is this:
I bought a zz4 shortblock and I will be putting my afr 190's on it with a magnum 270HR cam, RPM air gap intake and no emissions equipment. I am getting the #875-16 lifters, #3136 timing set, #7940-16 pushrods, 1.6 magnum roller rockers, and the #08-1000 roller lifter install kit (all from COMP Cams). what other odds and ends do I need to find? Can I reuse the timing cover from my non-roller cam motor? Do I need a thrust button? The afr springs are good for .550 lift and with the 1.6 rockers I will have .533 lift. Is that enough room for error? Should I get a rev kit or a stud girdle (I've been known to abuse my motors)?
This is a weekend only street/strip car that will see at most 6000-6250 rpms.
Last edited by johns84bird; 08-22-2002 at 05:15 PM.
08-22-2002, 06:29 PM
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Looks like you have everything covered with the exception of the valve springs, you should allow an extra .050-.060 just to be safe. The springs that comp recommends for that cam are 1.43 OD,have an installed hieght of 1.750 and coil binds at 1.150.
Kit #08-1000 has the thrust plate included so you will not need a thrust button.
If you install the correct spring and do not plan on turning your motor more than 6000rpm(which is probably the limit of the cam) a rev kit is not needed.
Kit #08-1000 has the thrust plate included so you will not need a thrust button.
If you install the correct spring and do not plan on turning your motor more than 6000rpm(which is probably the limit of the cam) a rev kit is not needed.
08-23-2002, 08:22 AM
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Car: Pontiac Grand Prix GTP
Engine: 3.8L V6 SuperCharged
Thanks man. The springs I have are 1.45 OD but the afr catalog doesn't offer much more info. maybe they are good for .550" with the extra .050-.060 factored in already? if it said .550" lift maximum, I don't think that would mean they bind at that height, do you?
08-23-2002, 08:30 AM
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Car: 4
Engine: 6
Transmission: 5
There are untold numbers of horror stories on this BBS from people who have bought assembled heads and run cams near the limits of what the head mfr claimed for the springs they supplied, and had things wipe out spectacularly and expensively.
As cheap as valve springs are, I'd buy a set of 986s and slap them on there if I were you. I would not bother with a rev kit or stud girdle.
As cheap as valve springs are, I'd buy a set of 986s and slap them on there if I were you. I would not bother with a rev kit or stud girdle.
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