Comp 987s with G5X cam?
09-18-2003, 04:04 PM
#21
Re: Comp 987s with G5X cam? Ok....just got off the phone with Lou and he had the following to say.....
987s WILL work fine UP TO about 6600/6700....at that point they can/will start to float a little and hp will fall off at that point (no P-to-V danger though). I "can" just swap to the G5X-2 and go drive but it would be a good idea to upgrade to the 977s (I won't have HP fall off due to valve float) since I have to remove the heads flycut the pistons.
987s are borderline on too much pressure for the stock hydraulic lifters and 977s ARE too much so I need to upgrade to the Comp R lifter.
987s WILL work fine UP TO about 6600/6700....at that point they can/will start to float a little and hp will fall off at that point (no P-to-V danger though). I "can" just swap to the G5X-2 and go drive but it would be a good idea to upgrade to the 977s (I won't have HP fall off due to valve float) since I have to remove the heads flycut the pistons.
987s are borderline on too much pressure for the stock hydraulic lifters and 977s ARE too much so I need to upgrade to the Comp R lifter.
09-18-2003, 05:32 PM
#22
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Re: Comp 987s with G5X cam?
Ok....just got off the phone with Lou and he had the following to say.....
987s WILL work fine UP TO about 6600/6700....at that point they can/will start to float a little and hp will fall off at that point (no P-to-V danger though). I "can" just swap to the G5X-2 and go drive but it would be a good idea to upgrade to the 977s (I won't have HP fall off due to valve float) since I have to remove the heads flycut the pistons.
987s are borderline on too much pressure for the stock hydraulic lifters and 977s ARE too much so I need to upgrade to the Comp R lifter.
987s WILL work fine UP TO about 6600/6700....at that point they can/will start to float a little and hp will fall off at that point (no P-to-V danger though). I "can" just swap to the G5X-2 and go drive but it would be a good idea to upgrade to the 977s (I won't have HP fall off due to valve float) since I have to remove the heads flycut the pistons.
987s are borderline on too much pressure for the stock hydraulic lifters and 977s ARE too much so I need to upgrade to the Comp R lifter.
09-18-2003, 06:53 PM
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Re: Comp 987s with G5X cam?
I like my REVs
09-18-2003, 07:12 PM
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Re: Comp 987s with G5X cam?
yep....he said peak was 6300RPM with a shift point of 6600/6700RPM....
because money is tight, I'm going to upgrade my lifters with the cam and then do 977s a little later.....
because money is tight, I'm going to upgrade my lifters with the cam and then do 977s a little later.....
09-18-2003, 07:26 PM
#26
Re: Comp 987s with G5X cam?
You're doing heads too then? Cause I can't see pulling the heads just to upgrade lifters. I would go ahead and do the springs now if I were you, just because you have a lot of miles on your 987's so far. I'm sure the spring rate has decreased a bit with 20,000 miles on them.
) but they have to be pulled to flycut the pistons (with the Isky piston notcher) to make room for the valves. I'm going to change the springs as soon as I can, but with the cost of the cam, gaskets, ARP rod bolts (going to go to these while I'm in the motor), and lifters, the extra $150 for new valve springs and shims is probubly going to be just out of reach.....
