Engine noise after Head/Cam install

**LOWnMEAN** · 03-02-2006, 03:20 PM

Well I just got my car back after installing a set of PP Stage 2 LS6 heads and a comp 231/237 5.89 5.95 112 lobe sep. Well to get to the story I absolutely hate it, the damn thing sounds like a sewing machine, it doesnt appear that there is P/V clearance issues.....it isnt running rough.........isnt using oil. I have put about 200 miles on it and it hasnt gotten any better and it hasnt gotten any worse. The guys that did it both have a handfull of H/C LS1's and they say its normal............please tell me i can do something about this. Its embarrassing to be at a red light and have someone check out your car and when you go to pull out it sounds like an industrial sewer. I would appreciate any input.

**Deeavi** · 03-03-2006, 05:15 AM

Originally Posted by LOWnMEAN

Well I just got my car back after installing a set of PP Stage 2 LS6 heads and a comp 231/237 5.89 5.95 112 lobe sep. Well to get to the story I absolutely hate it, the damn thing sounds like a sewing machine, it doesnt appear that there is P/V clearance issues.....it isnt running rough.........isnt using oil. I have put about 200 miles on it and it hasnt gotten any better and it hasnt gotten any worse. The guys that did it both have a handfull of H/C LS1's and they say its normal............please tell me i can do something about this. Its embarrassing to be at a red light and have someone check out your car and when you go to pull out it sounds like an industrial sewer. I would appreciate any input.

Most Ls1 cars with cams sound like sewing machines. It has to do with agessive ramps on the camshaft. They are fast opening and closing making the valves snap when the open and shut, thus a clicking sound comes from the whole valve train. Mine sounds like that and I have gottne used to it. Just to be on the safe side, make sure you lifters are adjusted correctly.

If you have adjustable rockers?

Some may argue about the adjustment method, but I did it according to the Crane directions that came wth my lifters. They are supposed be adjusted two full turns after the pushrod stops turning with your fingers and the rocker makes contact with the valve - The easiest way this can be done is when the engine is cold and the lifters have bled down. Here is Crane's tech artical:

IMPORTANT LS1 VALVE ADJUSTING TIPS
When adjusting the lifter preload on a hydraulic roller camshaft,
special care must be taken to account for lifter bleed down. Install
the rocker arms on the studs and tighten the adjusting nuts to
achieve zero lash (with no preload and no pressure on the valves).
Be sure the setscrew in the adjusting nut does not contact the stud.
Now, rotate the crankshaft one full turn and adjust any loose rocker
arms to zero lash. Rotate crankshaft again one full turn and
adjust any loose rocker arms to zero lash.
Do not rotate the crankshaft during the remaining procedure.
Allow lifters to bleed down for 30 minutes. Adjust any loose rocker
arms to zero lash. Now, tighten each rocker arm adjusting nut
¼ turn. Allow the lifters to bleed down for 15 minutes. Repeat this
procedure seven more times for a total of two full turns. Be sure to
allow 15 minutes bleed down time after each ¼ turn.
The lifters now have the proper preload. While holding the adjusting
nut with a wrench, carefully tighten the setscrew in the adjusting
nut of each rocker arm. Do not rotate the nut during this
process. Allow another 30 minutes bleed down time for this final

Hope this helps!

**BIG D's SS** · 03-03-2006, 05:32 AM

I have an agressive cam and mine sounds just nasty as hell.

**LOWnMEAN** · 03-03-2006, 09:06 AM

I appreciate the info guys, i dont have adjustable rockers so thats not an issue.........I guess I will just have to get use to it. Does it get any better or worse the more miles you put on it?

**BIG D's SS** · 03-03-2006, 09:10 AM

As far as noise are you talking like a ticking sound or smooth idle or exactly what are you talking about? Just a little more info would help.

**LOWnMEAN** · 03-04-2006, 03:54 PM

Its a ticking noise

**408WS6** · 03-12-2006, 10:14 AM

Originally Posted by LOWnMEAN

Its a ticking noise

You sound like you have too much preload on your lifters. Since you have Patriot heads, I'm assuming that the heads have been milled. This means that when you torque down the rocker arms, you'll be putting additional preload on your lifters. Crane makes a shim kit thats about $8.50 that you use under the rockers arms to help compensate for milled heads.

But you need to have it checked out before you damage your motor.

**greatwhitess** · 03-14-2006, 11:48 AM

PP LS6 Heads are stock deck height. You probably need longer PRs. The base circle of your cam is smaller (1.45) than stock (1.55) therefore you need a longer PR to compensate. My stock rods were 7.3875. Most are 7.38x , I had to go with 7.425 because the 7.4s were to short and I didn't have enough preload. Also they were loud as h*ll just like you are saying. The 7.425 rods put my preload @ about .060 which is within the recommended range.

Hope this helps.