Pushrod guideplate HELL....
07-11-2006, 07:44 AM
#1
Pushrod guideplate HELL.... I am told that there are only two guide plates that will work on the LT1, the GM plates and the Isky plates.
The GM plates are not hardened, they will not pass the file test like a pushrod will. However I am told that the Iskys are heat treated therefore being hardened. Because the GM plates are not this results in mild to severe wear like this:
.
I have three possible solutions to remedy this problem, please post your thoughts. I want to ensure that I don't have any more guide plate problems in the future.
1. I can take 8 brand new GM guide plates and have them heat treated to make them truly hardened. How do I do this?
2. I can use a bare head to assemble the Isky plates before being installed on the engine. After trimming the Isky plate to move them closer together, I can place an Isky plate on top of a GM plate and align the pushrod guide slots and spot weld the two halves together. This will make actual install of the welded Isky plates much easier.
3. Can I place an Isky plate on top of a GM plate and install them both on the engine? The GM plate would be used to align the Isky plate but because the Isky plate is hardened it will do the work to retain the push rod. Only problem I see here is maybe a height problem and the cover not fitting.
It is truly a damn shame that a simple thing such as a guide plate can cause this much trouble. I have 15 out 16 guide plate slots that are acceptable and one that wants to go crazy. I have eliminated all possibilites of bad rocker geometry, wrong pushrod length and even the optispark to be causing my guide plate problem.
It would make sense to me that any wear on the GM plate is NOT normal, if the damn things were hardened I am will to bet that wear would not occur.
The GM plates are not hardened, they will not pass the file test like a pushrod will. However I am told that the Iskys are heat treated therefore being hardened. Because the GM plates are not this results in mild to severe wear like this:
.I have three possible solutions to remedy this problem, please post your thoughts. I want to ensure that I don't have any more guide plate problems in the future.
1. I can take 8 brand new GM guide plates and have them heat treated to make them truly hardened. How do I do this?
2. I can use a bare head to assemble the Isky plates before being installed on the engine. After trimming the Isky plate to move them closer together, I can place an Isky plate on top of a GM plate and align the pushrod guide slots and spot weld the two halves together. This will make actual install of the welded Isky plates much easier.
3. Can I place an Isky plate on top of a GM plate and install them both on the engine? The GM plate would be used to align the Isky plate but because the Isky plate is hardened it will do the work to retain the push rod. Only problem I see here is maybe a height problem and the cover not fitting.
It is truly a damn shame that a simple thing such as a guide plate can cause this much trouble. I have 15 out 16 guide plate slots that are acceptable and one that wants to go crazy. I have eliminated all possibilites of bad rocker geometry, wrong pushrod length and even the optispark to be causing my guide plate problem.
It would make sense to me that any wear on the GM plate is NOT normal, if the damn things were hardened I am will to bet that wear would not occur.
07-11-2006, 08:53 AM
#2
Well buddy i posted in another thread you put up i pulled my recipt file out of all the parts i bought for my carlastnight and indeed the part# they sent me was supposed to be hardend guidplate but mine did not pass the file test either.Another thing the price listed for the hardened guideplates is cheaper than the non-hardend go figure by 3 tiumes cheaper 
Well im ordering both sets today and doing a file test on them ill let you know what happens.I had bought mine about the same time as you 7 months ago i wonder if they had a bad batch where the plates didnt get hardened???
Well im ordering both sets today and doing a file test on them ill let you know what happens.I had bought mine about the same time as you 7 months ago i wonder if they had a bad batch where the plates didnt get hardened???
07-11-2006, 09:39 AM
#3
Or the forth way that we have found to work best.
This is much easier with the engine out but we have done many sets on car. The trick for on car is to set down a welding cloth to catch the berry's.
take and set up each individual rocker arm so it has the best travel over each valve tip. you do one cylinder at a time and tack weld the plate. pull the plate back off and put on a solid weld then re-install the playtes and line them back up. Torque the stud's down and double check your work for best travel over the valves.
DONE!
It does take a while to do it right but it is well worth it and your valve train will be quieter then it has ever been
BTW if you stack the plates the rockers will most likey bottom out on the stud
This is much easier with the engine out but we have done many sets on car. The trick for on car is to set down a welding cloth to catch the berry's.
take and set up each individual rocker arm so it has the best travel over each valve tip. you do one cylinder at a time and tack weld the plate. pull the plate back off and put on a solid weld then re-install the playtes and line them back up. Torque the stud's down and double check your work for best travel over the valves.
DONE!
It does take a while to do it right but it is well worth it and your valve train will be quieter then it has ever been
BTW if you stack the plates the rockers will most likey bottom out on the stud
