Wrong lifters, now what??
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Wrong lifters, now what?? So I realized that I ordered the wrong lifters for my build. I got Comp 875's and didnt know they are meant for use with adjustable rockers. Ive got a couple issues here. Ive already torqued down the heads, are my gaskets screwed??
I think Im going to get the 850's and install them. My heads are LS3, so there isnt as much stuff for rockers to choose from. I have trouble spending 800-1000 for a set of adjustable rockers, thats crazy for my build. I mocked up this setup and degreed the cam (I used checking springs) and noticed that my NEW GM intake rockers require a slightly different pushrod length then my USED exhaust GM rockers. Can anyone advise me what rockers I could use?
Im at a bit of crossroads because If I have to buy another set of lifter fro 200 and set of lifters for 400-600, I almost might as well just buy the Comp or T&D shaft mount adjustable.
OR just get some new pushrods and use 850's and let the lifters make up the difference in length.
Also, anyone use Comp pushrods??
I think Im going to get the 850's and install them. My heads are LS3, so there isnt as much stuff for rockers to choose from. I have trouble spending 800-1000 for a set of adjustable rockers, thats crazy for my build. I mocked up this setup and degreed the cam (I used checking springs) and noticed that my NEW GM intake rockers require a slightly different pushrod length then my USED exhaust GM rockers. Can anyone advise me what rockers I could use?
Im at a bit of crossroads because If I have to buy another set of lifter fro 200 and set of lifters for 400-600, I almost might as well just buy the Comp or T&D shaft mount adjustable.
OR just get some new pushrods and use 850's and let the lifters make up the difference in length.
Also, anyone use Comp pushrods??
I don't see why your rockers would change pushrod length in this scenario. What kind SOLID test lifter are you using to check it with? Seeing as you've already bolted the heads down, it seems like you're doing it backwards. Thats what shims are for.
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You are right, it seems a bit out of order, but I talked to a guy at comp and he said that since I was using light checking springs, it shouldnt be an issue using the actual lifter. He also mentioned there isnt a solid version of the 875. Im not sure, but converting them looks to be impossible due to the retainer being really weird. Since I had the lightweight springs in, I was able to manipulate the rocker and valve and pushrod all independantly. Doing this I was confident that using the actual lifter wasnt affecting anything.
So its an LQ4 that Im putting LS3 heads on. The new out of the bag LS3 intake rockers have about .025" less clearance then the used exhaust rockers I took off the old 317 heads. I found this by using an adjustable pushrod.
Im not how to shim these factory rockers independantly, with that rocker support in there underneathe all the rockers at once, can you explain how someone could shim an intake and leave the exhaust one??
Im going to put in a set of 850's they are soaking in oil as we speak, and Im thinking of getting a set of comp ultra pro magnum rockers, but they are 1.8 ratio, which is a lot of lift with my cam.
So its an LQ4 that Im putting LS3 heads on. The new out of the bag LS3 intake rockers have about .025" less clearance then the used exhaust rockers I took off the old 317 heads. I found this by using an adjustable pushrod.
Im not how to shim these factory rockers independantly, with that rocker support in there underneathe all the rockers at once, can you explain how someone could shim an intake and leave the exhaust one??
Im going to put in a set of 850's they are soaking in oil as we speak, and Im thinking of getting a set of comp ultra pro magnum rockers, but they are 1.8 ratio, which is a lot of lift with my cam.
A solid lifter is a check lifter, not a solid roller replacement lifter. I think you misunderstood what I was saying.
I dont see how your rockers have two different offsets and/or ratios. They should both be the same height off the valve. Do you have an LS3 exhaust rocker you could test with instead of what you are using?
I dont see how your rockers have two different offsets and/or ratios. They should both be the same height off the valve. Do you have an LS3 exhaust rocker you could test with instead of what you are using?
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Sorry, I was a bit confused there, you are right about that. 
I put my pushrod length checker down in the intake side, bolted on the intake rocker arm and found my rod length by turning the pushrod until it extended until the rocker didnt have any 'wiggle' in it, and the pushrod didnt want to wiggle around or turn easily. I did same with the exhaust side, and the checked comes up with a slightly different length, around 0.020"-0.025". Im wondering if this is because that exhaust rocker is an old part, from a 2006 engine with I think around 60000 miles on it. It might have some where on it. I have another set from a 2001 4.8L that Im going to try. I do not have an actual LS3 or L92 rocker, wish I did, but Im thinking of getting a set of Yella Terra 1.7s, they will be all new and hopefully all good.
Thanks for the help, it looks like no one else wants to chime in here, probly cuz it sounded like I was totally retarded, which I felt like trust me.
I put my pushrod length checker down in the intake side, bolted on the intake rocker arm and found my rod length by turning the pushrod until it extended until the rocker didnt have any 'wiggle' in it, and the pushrod didnt want to wiggle around or turn easily. I did same with the exhaust side, and the checked comes up with a slightly different length, around 0.020"-0.025". Im wondering if this is because that exhaust rocker is an old part, from a 2006 engine with I think around 60000 miles on it. It might have some where on it. I have another set from a 2001 4.8L that Im going to try. I do not have an actual LS3 or L92 rocker, wish I did, but Im thinking of getting a set of Yella Terra 1.7s, they will be all new and hopefully all good.
Thanks for the help, it looks like no one else wants to chime in here, probly cuz it sounded like I was totally retarded, which I felt like trust me.
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Sorry, I was a bit confused there, you are right about that.
I put my pushrod length checker down in the intake side, bolted on the intake rocker arm and found my rod length by turning the pushrod until it extended until the rocker didnt have any 'wiggle' in it, and the pushrod didnt want to wiggle around or turn easily. I did same with the exhaust side, and the checked comes up with a slightly different length, around 0.020"-0.025". Im wondering if this is because that exhaust rocker is an old part, from a 2006 engine with I think around 60000 miles on it. It might have some where on it. I have another set from a 2001 4.8L that Im going to try. I do not have an actual LS3 or L92 rocker, wish I did, but Im thinking of getting a set of Yella Terra 1.7s, they will be all new and hopefully all good.
Thanks for the help, it looks like no one else wants to chime in here, probly cuz it sounded like I was totally retarded, which I felt like trust me.
I put my pushrod length checker down in the intake side, bolted on the intake rocker arm and found my rod length by turning the pushrod until it extended until the rocker didnt have any 'wiggle' in it, and the pushrod didnt want to wiggle around or turn easily. I did same with the exhaust side, and the checked comes up with a slightly different length, around 0.020"-0.025". Im wondering if this is because that exhaust rocker is an old part, from a 2006 engine with I think around 60000 miles on it. It might have some where on it. I have another set from a 2001 4.8L that Im going to try. I do not have an actual LS3 or L92 rocker, wish I did, but Im thinking of getting a set of Yella Terra 1.7s, they will be all new and hopefully all good.
Thanks for the help, it looks like no one else wants to chime in here, probly cuz it sounded like I was totally retarded, which I felt like trust me.
Last edited by rojs234; Jun 11, 2011 at 11:21 AM.
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Wow, thanks Ron, I never thought of that. Ill make Im on the base circle next time. Im busy today, maybe tomorrow. I got a new set of head gaskets, and the right lifters now, so Ill be in better shape. Ill try to degree the cam again with the heads off this time, although Im pretty sure I got it last time and it was good. I dont really have anything to take the place of a pushrod to connect the lifter to my dial indicator. I dont have anything to use in place of a regular hydraulic lifter either. I suppose for just degreeing the cam I could sacrifice one of the old stockers right?? And turn it into a solid if possible.
It sounds like you are checking pushrod length at the same place on crank revolution for both valves. I'm guessing at TDC on compression stroke. This is not always the case. If you will slowly rotate the engine with your length checker in place and do the "wiggle " thing, you will probably find that the point where the lifter is at its lowest point on the cam and the pushrod the longest is completely different on the intake and exhaust lobes. Depending on the design of the ramps, it may not be 180* from the high point of the lift either. I'll bet you find the length is much closer between the two doing it this way. What I'm trying to say is you're problably checking it where one of the valves is already on eithr the opening or closing ramp. Ron
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Really?? They are 77 bucks a piece this side of the border, an expensive F up on my part. Live and learn.
Im not sure why I did this, but I sprayed them permatex high tack gasket sealer stuff. They got pretty much destroyed while I took the heads off.
I think that stuff would work better on like a water pump gasket thats slipping out of the way before you get the pump on or something. Im not going to use it on attempt number 2.
Im not sure why I did this, but I sprayed them permatex high tack gasket sealer stuff. They got pretty much destroyed while I took the heads off.
I think that stuff would work better on like a water pump gasket thats slipping out of the way before you get the pump on or something. Im not going to use it on attempt number 2.
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If you're degreeing the cam with the heads off, you might try this to help hold a pushrod straight. I used an old head gasket for a pattern and cut a piece of 1/8 plate to cover one cylinder from the two lower head bolt holes to just above the two pushrod holes. Then using the old gasket as pattern I drilled the four head bolt holes and the two pushrod holes just slightly bigger than the 5/16 pushrods. Since you can't find bolts the right size, I cut spacers out of pipe or use washers and the shortest head bolts to bolt it to block. Then you can put your pushrods in place and set up your dial indicator (hopefully a magnetic one) on the plate so it registers on the end of the pushrods. The closely fit holes will keep your pushrods moving straight up and down. One thing to watch...if this is an LQ9 or an LS2, you will have to use washers under the plate to space it up to clear the pistons rising out of the block. (about .010) Taking old lifters apart and using small spacers inside is a good way to get a couple solid lifters. Good luck, Ron
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Wow Ron, that sounds pretty handy what you built there, I never thought or heard of anything like that before. That would be pretty handy.
Mines an LQ4.
Is it possible for the dial indicator to fit and hold into the end of an old pushrod?? I wonder about drilling an end of a pushrod so the hole is bigger for the dial indicator to fit in better.
I honestly cant see doing this requiring a solid lifter, theres no way just a dial indicator and the weight of a pushrod are going to compress a lifter to the point where itll make a difference in the readings.
Mines an LQ4.
Is it possible for the dial indicator to fit and hold into the end of an old pushrod?? I wonder about drilling an end of a pushrod so the hole is bigger for the dial indicator to fit in better.
I honestly cant see doing this requiring a solid lifter, theres no way just a dial indicator and the weight of a pushrod are going to compress a lifter to the point where itll make a difference in the readings.
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Wow Ron, that sounds pretty handy what you built there, I never thought or heard of anything like that before. That would be pretty handy.
Mines an LQ4.
Is it possible for the dial indicator to fit and hold into the end of an old pushrod?? I wonder about drilling an end of a pushrod so the hole is bigger for the dial indicator to fit in better.
I honestly cant see doing this requiring a solid lifter, theres no way just a dial indicator and the weight of a pushrod are going to compress a lifter to the point where itll make a difference in the readings.
Mines an LQ4.
Is it possible for the dial indicator to fit and hold into the end of an old pushrod?? I wonder about drilling an end of a pushrod so the hole is bigger for the dial indicator to fit in better.
I honestly cant see doing this requiring a solid lifter, theres no way just a dial indicator and the weight of a pushrod are going to compress a lifter to the point where itll make a difference in the readings.
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Ya, I got a magnetic base dial indicator and Im pretty sure I can get it to work with just the push rod. I use something to push on the body of the lifter, like a clean screwdriver or something to make sure it follows the cam and probly use the plastic retainer. Im pretty sure that I got it degreed already anyways, when I had it all set up before, I got a 108.5 for the intake centreline and my cam card says 109, so I think its good, but Ill go thru the motions again anyways cuz its good learning and make sure Im good.
Also, Ive got truck style steam vents, and Im installing a FAST 102 for a car. My vents hit the intake, what do LS3 vents look like, and does anyone know the part number for them?? Has anyone ever cut up the factory ones and used compression fittings and copper tubing to make your own??
Also, Ive got truck style steam vents, and Im installing a FAST 102 for a car. My vents hit the intake, what do LS3 vents look like, and does anyone know the part number for them?? Has anyone ever cut up the factory ones and used compression fittings and copper tubing to make your own??
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Do you mean the LS3 valves are different in that both intake and exhaust are the same to each other but different as a pair from the older cathedral port stuff? So me using as LS3 intake rocker and and LQ4 rocker makes them different??
Im pretty sure I have upgraded valves. I know my springs are patriot gold duals. Would the upgraded valves be different.
Im pretty sure I have upgraded valves. I know my springs are patriot gold duals. Would the upgraded valves be different.
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Holy smack, I just did some searching like you said, and I see what you is saying.
I read...
https://ls1tech.com/forums/generatio...-question.html
and...
https://ls1tech.com/forums/generatio...erent-l92.html
I went out and had a quick look at mine, put a straight edge across the tips, and I got about .015 difference between intake and exhaust, but I just did a quick job of it, Im watching the baby tonite as the wife is sick so I couldnt leave him.
This makes me wonder what GM does with the factory setups in LS3 Camaro's, do they different pushrods for intake and exhaust, or does the LS3 exhaust rocker have a mod to them to make up for this??
I read...
https://ls1tech.com/forums/generatio...-question.html
and...
https://ls1tech.com/forums/generatio...erent-l92.html
I went out and had a quick look at mine, put a straight edge across the tips, and I got about .015 difference between intake and exhaust, but I just did a quick job of it, Im watching the baby tonite as the wife is sick so I couldnt leave him.
This makes me wonder what GM does with the factory setups in LS3 Camaro's, do they different pushrods for intake and exhaust, or does the LS3 exhaust rocker have a mod to them to make up for this??
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