L98 Rocker Stud conversion
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Joined: Oct 2002
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From: Houston TX
L98 Rocker Stud conversion
I am hoping someone can send me the right direction here. I am rebuilding my L98 - TPI from my 1985 C4. When I disassembled it, one of the rocker studs threads looked to be in very poor shape. Probably key to the lifter noise.
Anyway, I decided to convert over to Screw in studs and guide plates. First time doing this. I finsihed the job on the bench and promptly ran over to put the heads back on the block.
Well, not thinking, the pushrods now do not even come close to being long enough. What is the best way to determine push rod length requirements? The rocker arm bottoms out way before the push rod reaches the cup.
Has anyone done a stud conversion on an L98 before.
Thanks
Burning Brakes
Joined: Nov 2001
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From: Austin TX
Re: L98 Rocker Stud conversion (HoustonBob)
Converting from pressed in studs to screw-in studs will not change your
valve train geometry or pushrod length requirements.
I sounds to me like you did not mill the rocker stud bosses down. They need
to be milled down roughly the amount of the thickness of the guideplate
and hex nut on the stud. Unless you have a milling machine or a guide/seat
machine in your shop/garage, you will need to have a machine shop do this.
You will also need to drill out the pushrod guides (slots) in the head if
you're going to use guide plates.
Good luck,
Dan
[Modified by danno85, 4:44 PM 6/1/2003]
valve train geometry or pushrod length requirements.
I sounds to me like you did not mill the rocker stud bosses down. They need
to be milled down roughly the amount of the thickness of the guideplate
and hex nut on the stud. Unless you have a milling machine or a guide/seat
machine in your shop/garage, you will need to have a machine shop do this.
You will also need to drill out the pushrod guides (slots) in the head if
you're going to use guide plates.
Good luck,
Dan
[Modified by danno85, 4:44 PM 6/1/2003]
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Joined: Oct 2002
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From: Houston TX
Re: L98 Rocker Stud conversion (HoustonBob)
Thanks Danno,
I was afraid of that! All well off to the machine shop we go. Thanks for the heads up on the clearancing the head as well. Since I obviously do not know what I am doing here.
I might as well ask which way the offset guide plates go, I assumed the step would riser closer to the rocker arm, but not sure now.
Again, thanks
HoustonBob
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Re: L98 Rocker Stud conversion (HoustonBob)
i hope you used a tap with a .375 pilot ground on the end or your studs could not be inline. if you do not tap the heads in in a milling machine or use a tap with a pilot you could have a stud alignment problem which will cause a big problem with valve train geometry :chevy
Burning Brakes
Joined: Nov 2001
Posts: 1,189
Likes: 2
From: Austin TX
Re: L98 Rocker Stud conversion (HoustonBob)
Thanks Danno,
I was afraid of that! All well off to the machine shop we go. Thanks for the heads up on the clearancing the head as well. Since I obviously do not know what I am doing here.
I might as well ask which way the offset guide plates go, I assumed the step would riser closer to the rocker arm, but not sure now.
Again, thanks
HoustonBob
I was afraid of that! All well off to the machine shop we go. Thanks for the heads up on the clearancing the head as well. Since I obviously do not know what I am doing here.
I might as well ask which way the offset guide plates go, I assumed the step would riser closer to the rocker arm, but not sure now.
Again, thanks
HoustonBob
to the rocker arm:
Dan
