After me and my friend installed my S2 GTP heads with 10.9.1 compression and I "think" what Craig said was they were milled 28th to 35th thousands <- spelling? I was told I can use the stock pushrods but I think I need shorter ones after hearing the car.

The noise is coming from under the driver side valve cover, so I took it off and everything seemed fine. I was told to check preload but not sure how to check? He said that it should be fine if preload is around 30th to 40th thousands?
Has anyone went through this also, if so let me know what happen? Could it be a lifter? Everything was fine before the heads went on so can swaping the heads cause a lifter to go bad I wouldnt think so cause the noise started as soon as we started the car?

cam specs if needed is 224/224 561.561 112lsa

 

How long did you let it run? Best case senario is you didn't allow enough time for the lifters to pump up. After a head/cam swap the engine will be ticking loud as hell for a few minutes, this is normal. I've even heard that sometimes the lifters can take a significant amount of time to pump up (30+ minutes). Mine only ticked like crazy for about 3-5 minutes both times I had the heads off.

With that TR cam, it has a .015" smaller base circle, but your heads are milled ~.030", This would mean you'd need a .015 shorter pushrod, but nobody sells 7.385" pushrods, the closest to that number would be the ones you have 7.400". The lifters will be able to make up that small difference.

I'm not sure about the preload, I just torqued my rockers to 22 ftlbs and has been well, perhaps someone could explain the process to us?

Also, did you remove the oil pump? If so you might have damaged the O-ring, how is your oil pressure?

I'm all out of ideas

Matt

 

Thanks for the info,

This was just a head swap only since I had the cam in there from before. I drove the car home after a few warm ups, about 1 hour (30 miles). We torqued down the rockers to 22lb's also and after driving the car home I figured I would take a look. Everything seemed to be fine as far as I could see

I am guessing I need shorter pushrods but I was told by GTP other people run the stockers with no problem so maybe its something else?

 

no one else has had this happen?

 

Actually the stock LS1s Base Circle is 1.552”
That equals a 0.776” centerline to lobe heel distance (1/2 the base circle distance)

The TR224s Base Circle is approx 1.502”
That equals a 0.751” centerline to lobe heel distance

Subtract the two numbers: The TR224 centerline to lobe heel distance is .025” less than stock

If the cam is all you changed, you would need a .025" [longer] pushrod.
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You had your heads milled about .025"

If all you did was install your milled heads and retained your stock cam, you would require a .025" [shorter] rod.
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You did both .... It becomes "tit for tat". You need to use the stock 7.40" pushrod.

If it's clattering with stock length rods, it's not because of lifter preload problems associated with the wrong length pushrod.

Remember, these fast ramp cams (like your TR224) will make the LS1 sound like a sewing machine. The only guys that don't bitch about the sewing machine noise are the guys that have such a loud exhaust, they don't really even hear it over all the other noise.

Ron,

 

CHECKING LIFTER PRELOAD IN THE LS1 (NON ADJUSTABLE ROCKERS)
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1. Turning the engine, bring one of the cylinders to TDC. The valves will be fully closed.

2. Now, fully loosen one of the rocker arm bolts on that cyl.

3. Then start turning the rocker arm bolt down until the lifter is at "zero lash". You will be able to tell it is at zero lash when the rocker bolt gets very hard to turn. It gets hard to turn because the valve spring starts to compress. Again, stop turning the bolt as soon as you feel resistance to turning.

4. Mark the bolt with a marker.

5. Now count how many turns it takes to completely tighten the rocker bolt to 22 FT/LB.

The bolt should have turned between 1 3/4 to 2 turns for the acceptable GM lifter peload.

If you don't get the 1 3/4 to 2 bolt turns of preload, you need a different length pushrod. (IE: you need a shorter rod if it takes much more than 2 turns, and a longer rod if it takes much less than 1 3/4 turns). I really think anywhere between 1 to 2 turns is acceptable. Remember, hyd. lifters can operate within a fairly large margin of preload as long as it's not excessive.


NOTE: You really only need to do this on one cylinder. The rest will be the same.

NOTE: If you have aftermarket Comp Cams “Type R” lifters, I understand that those like less preload than stock lifters. Instead of 1 3/4 to 2 full turns as indicated above, about 3/4 to 1 turn may be more acceptable.

NOTE: Allways run the engine prior to checking the preload so as to get the lifters pumped up. This is important if you just installed new lifters or had the old ones out while installing a new cam.

Hope this helps,
Ron

 

Thanks, I will have to try that

I am not to worried about the sound its if something is wrong what bothers me.
I have a loud exhaust set up Mac headers with ORP and Loudmouth and I still hear it? I can live with the noise but just dont want something bad to happen and do all this damn work again.

I have stock lifters, rocker arms and Crane Cams Pushrods.
I only changed the heads, cam was in there from a long time ago.

Heads came with double springs and titainum retainers.

 

[quote
I have stock lifters, rocker arms and pushrods.
I only changed the heads, cam was in there from a long time ago.
Heads came with double springs and titainum retainers.

[/quote]

Maybe I am misreading what you are saying - but are you saying you have stock pushrods with a TR224 cam?

 

Great post Tin Indian!

 

I have a problem with my TR 224 cam. Actuallyy it's not the cam's fault. If I let the car idle for more then two or three minutes I get a pretty loud ticking noise. Bring the RPMs back up to 1500 (or higher) ande hence the oil pressure, the tick goes away. The tick is coming from the #3 exhaust valve. Actually the rocker arm. My lifter isn't staying pumped up. When I order the new heads, I'm also ordering and installing a set of Comp R lifters. Or the Crane lifters, haven't made up my mind yet.

 

Ok I edited my last post about stock Pushrods. It has been so long since I installed my cam I just checked a box of stock parts and there it was a Crane Cams Pushrods box that I forgot about
"Crane Heat Treated Pushrods, 7.400" (Stock length LS1)" so basicly I have a stock length pushrod.

 

wicked are those patriot heads? if so PM me...

 

His first post says "GTP."

 

Prepare for some measuring if you go with the Comp R's. I spent quite a bit of time getting my rockers shimmed "just right" for the Comp R's. Comp Cams recommendation was for use with adjustable valve train (found out AFTER I bought them). The R lifters like .000 to .005 of pre-load (per Comp Cams tech line). With GTP's milled .015, a TR224, 7.4 PR's, and YT rockers I needed a .044 shim. The shims from YT were too much (.047) - made an awful racket, I finally ended up with a stainless washer that measured .044 and all the intermittent noises finally went away.

 

Ok I found out the problem, I thought it could be a injector so I put back my 28lbs and it still ticked. So today me and my friend replaced the gasket on the driver side air tube and that fixed it!!Just thought I would post that up if anyone else has a simular problem so they wont have to go through taking everything apart again. I removed my AIR system and made a block off plate but it was not flush.