stroker lsj build
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Joined: 02-01-11
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From: modesto
Ok so did some comparing between the GMRs and stock.
The stock base circle spec is 1.181 -0.003 so almost 30mm
GMRs is 1.102 right at 28mm.
With that 2mm difference in the base circle i need to gain 1mm of valve stem length and lifter hight.
I pulled a lifter a part to take some measurements. Looks like the lifters have about 0.045 more travel. Which is good cuz i only need 1mm or 0.039. Now for the valves.
Couple of options i can choose from.
1 buy custom valves 1mm longer
2 have the seats cut 1mm deeper
3 mod the followers.
Im Gona attempt the mod the followers to gain the needed 1mm.
I ordered the needed parts from summit cost me 36$.
The stock base circle spec is 1.181 -0.003 so almost 30mm
GMRs is 1.102 right at 28mm.
With that 2mm difference in the base circle i need to gain 1mm of valve stem length and lifter hight.
I pulled a lifter a part to take some measurements. Looks like the lifters have about 0.045 more travel. Which is good cuz i only need 1mm or 0.039. Now for the valves.
Couple of options i can choose from.
1 buy custom valves 1mm longer
2 have the seats cut 1mm deeper
3 mod the followers.
Im Gona attempt the mod the followers to gain the needed 1mm.
I ordered the needed parts from summit cost me 36$.
If you don't want to run solids you can take a spacer that is the right diameter and thickness and tig weld them to the bottom of the stock lash adjusters to hold them in place.
Thread Starter
Senior Member
Joined: 02-01-11
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From: modesto
The thing about slaping solids in is it throughs the valve geometry off and side loads the stem causing the valve train to bind.
Interested in the welding a shim to the followers.
He said weld to the lifter/adjuster. Which would throw the rocker geometry off by the same amount.
Which brings up the point: is 1mm even worth messing with? Do you really believe its going to throw things off THAT much? Trig it out with the length of the valve with the distance from the lifter to valve stem. You're talking about a tiny fraction of a degree here.
Which brings up the point: is 1mm even worth messing with? Do you really believe its going to throw things off THAT much? Trig it out with the length of the valve with the distance from the lifter to valve stem. You're talking about a tiny fraction of a degree here.
Thread Starter
Senior Member
Joined: 02-01-11
Posts: 2,799
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From: modesto
He said weld to the lifter/adjuster. Which would throw the rocker geometry off by the same amount.
Which brings up the point: is 1mm even worth messing with? Do you really believe its going to throw things off THAT much? Trig it out with the length of the valve with the distance from the lifter to valve stem. You're talking about a tiny fraction of a degree here.
Which brings up the point: is 1mm even worth messing with? Do you really believe its going to throw things off THAT much? Trig it out with the length of the valve with the distance from the lifter to valve stem. You're talking about a tiny fraction of a degree here.
The point of this is to correctly run the GMRs and maintain the stock valve geometry.
I think the number is 1.5 degrees. That's going off of memory though. I have ran cars like this with no problems. If you want to maintain stock geometry you would have to raise the valve and lash adjuster the same amount.
Thread Starter
Senior Member
Joined: 02-01-11
Posts: 2,799
Likes: 2
From: modesto
Well Im sticking a 1mm lash cap on the valve and moding followers to fit over.
I pulled a lash adjuster apart and came up with 0.045 or extra travel Wich is good cuz i only need 0.039.
I have a few sets of solid lifters laying around now so i can easily use them if this idea Dosnt work