***7.450 push rods***
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
^ That is why YT's instructions avoids that part... shimming the rocker up would move the wipe pattern "back" toward the manifold right?
It makes sense to set that then get proper pushrods, however, assuming your pushrods are of acceptable length, as mine were, adding the shims would get you less pre-load, as shimming lessense the distance the rocer arm unit can move dowm when going from zero lash to wrench tight.
It makes sense to set that then get proper pushrods, however, assuming your pushrods are of acceptable length, as mine were, adding the shims would get you less pre-load, as shimming lessense the distance the rocer arm unit can move dowm when going from zero lash to wrench tight.
Safety Car
Joined: Apr 2004
Posts: 3,932
Likes: 8
From: Hayward California
Adding shims increase the fulcrum height and moves the pattern towards the exhaust manifold. A 0.045" shim will increase pushrod length by 0.071" since you have to run through a parallel triangle to get the height increase at the pushrod due to a height increase at the fulcrum.
Le Mans Master
Joined: Feb 1999
Posts: 7,121
Likes: 0
From: Vilano Beach FL
Holy Smokes! This has been an incredible education on rockers!
Question (if the OP doesn't mind
) - are the YT's much better than the HS product? I'm assuming either is much better than the OEM-ers?
I'm doing a cam swap (and upgraded springs, etc.) so it would be a GREAT time to install some aftermarket rockers!
Question (if the OP doesn't mind
) - are the YT's much better than the HS product? I'm assuming either is much better than the OEM-ers?I'm doing a cam swap (and upgraded springs, etc.) so it would be a GREAT time to install some aftermarket rockers!
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Holy Smokes! This has been an incredible education on rockers!
Question (if the OP doesn't mind ) - are the YT's much better than the HS product? I'm assuming either is much better than the OEM-ers?
I'm doing a cam swap (and upgraded springs, etc.) so it would be a GREAT time to install some aftermarket rockers!
Question (if the OP doesn't mind
) - are the YT's much better than the HS product? I'm assuming either is much better than the OEM-ers?I'm doing a cam swap (and upgraded springs, etc.) so it would be a GREAT time to install some aftermarket rockers!
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Deno,
Here are the area's to look at for contact. Contact near the pushrod cup will also shift the pushrod laterally (or try to). Contact near the spring would be due to the large retainer on a dual spring. Since the HS rockers are anodized, you should see something just by inspection.
Here are the area's to look at for contact. Contact near the pushrod cup will also shift the pushrod laterally (or try to). Contact near the spring would be due to the large retainer on a dual spring. Since the HS rockers are anodized, you should see something just by inspection.
Last edited by SLPRC5; Aug 27, 2007 at 03:46 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Feb 1999
Posts: 7,121
Likes: 0
From: Vilano Beach FL
I'm worry about the horror stories of people having an OEM rocker come apart and shower the motor with needle bearings
Burning Brakes
Joined: Oct 2004
Posts: 931
Likes: 35
From: Rowlett, Texas
VetteNuts: You-da-Man.
I think I agree with everything you said in this thread.
With this much good info Ol Sleeper should whip his noise problem, then he can live up to his nickname.
DG
I think I agree with everything you said in this thread.
With this much good info Ol Sleeper should whip his noise problem, then he can live up to his nickname.
DG
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Here's how I view it. I found my stock rockers had a wide wipe pattern and some of them were wiping on the side of the valve stem (front to back when looking at the head from the side of the car). I have seen others report similar findings. With a stock spring and low lift of the stock cam, the loads into the valve guides were probably acceptable to GM with this setup. Now you come along and install an aftermarket cam that has larger lift. This sets the rocker contact point when closed closer to the intake and the larger lift increases the wipe length. Both of these factors are bad for guide wear. Next, consider the stiffer valve springs, this exacerbates the situation ever more since you likely have a poor wipe pattern and higher spring loads. The stock rockers are very well purpose designed parts, but my personal opinion is that aftermarket cam/spring loads will cause premature valve guide issues as compared to the stock motor. A correctly set aftermarket roller rocker will narrow the wipe pattern and is stiffer than the stock rocker, and thus better suited to handle the higher spring loads and larger lifts.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Yup! there is a lot of noise there!
More so than there should be! Mine do make noise with the HS RR's but not quite that much!
It made about that much when the 3.750's were in but with the 4.00's it still makes the sewing machine noise, like I stated to you that with the 15W 50 Mobile1 it did make a difference.
I have a feeling that with 4.25's it would be perfect (Adjustment would work too according with where my current adjustment is at! )
Keep me informed! I got your latest PM.
Thanks,Matt
More so than there should be! Mine do make noise with the HS RR's but not quite that much!
It made about that much when the 3.750's were in but with the 4.00's it still makes the sewing machine noise, like I stated to you that with the 15W 50 Mobile1 it did make a difference.
I have a feeling that with 4.25's it would be perfect (Adjustment would work too according with where my current adjustment is at!
)Keep me informed! I got your latest PM.
Thanks,Matt
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
The specs seem to indicate the YT's are definitely lighter which is a plus. There have been a few sets of the HS for sale recently, pretty good prices. They're the setup that uses a shaft to tie together pairs (not full on shaft mount) - they say that's supposed to reduce deflection and create a more stable valvetrain (?)
I'm worry about the horror stories of people having an OEM rocker come apart and shower the motor with needle bearings
I'm worry about the horror stories of people having an OEM rocker come apart and shower the motor with needle bearings
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Yup! there is a lot of noise there!
More so than there should be! Mine do make noise with the HS RR's but not quite that much!
It made about that much when the 3.750's were in but with the 4.00's it still makes the sewing machine noise, like I stated to you that with the 15W 50 Mobile1 it did make a difference.
I have a feeling that with 4.25's it would be perfect (Adjustment would work too according with where my current adjustment is at! )
Keep me informed! I got your latest PM.
Thanks,Matt
More so than there should be! Mine do make noise with the HS RR's but not quite that much!
It made about that much when the 3.750's were in but with the 4.00's it still makes the sewing machine noise, like I stated to you that with the 15W 50 Mobile1 it did make a difference.
I have a feeling that with 4.25's it would be perfect (Adjustment would work too according with where my current adjustment is at!
)Keep me informed! I got your latest PM.
Thanks,Matt
Some of us love it and some of us don't.
Last edited by SLPRC5; Aug 25, 2007 at 04:02 PM.
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Thanks everyone for the education on this subject. I'm waiting for the PR Checker and the YT RR to come in and then I'll post here what I found out.
Thanks
Sleeper
Thanks
Sleeper
Last edited by SLPRC5; Aug 25, 2007 at 08:35 PM.
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Hey Sleeper - Its my car that Vettenuts is working on and Yes the shims were in the package(.045 thick). I just ordered my 7.500 p.rods.
When we put the shims in the wipe moved about 1/32" to center and is now dead on. That caused the the need for extra lenght rods.
It will be fun to see who gets all this right first.
Good luck
BTW I have sent Vettenuts to the beach for some R & R which he really needs after all this.
When we put the shims in the wipe moved about 1/32" to center and is now dead on. That caused the the need for extra lenght rods.
It will be fun to see who gets all this right first.
Good luck
BTW I have sent Vettenuts to the beach for some R & R which he really needs after all this.
Hope you also gave him his favorite six pack beverage
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Well none of the good stuff ac come in yet to continue the work on this project of solving the sew machine sound to with in acceptance.
I email Patriot heads and explained to Gunnar what probles I was having with the other than normal valve train noise and the two sets of different push rods I have tried to limit the sewing machine sound.
This is his reply back:
"The pushrod is probably correct, the source of the notice could be the valve springs. The heads come with the Patriot Gold springs. They sometimes have a tendency to cause a slight sewing machine sound because of them being dual springs and the greater seat pressures".
So I hope I don't have to go in and change valve springs as a last resort in quieting this sound down.
I email Patriot heads and explained to Gunnar what probles I was having with the other than normal valve train noise and the two sets of different push rods I have tried to limit the sewing machine sound.
This is his reply back:
"The pushrod is probably correct, the source of the notice could be the valve springs. The heads come with the Patriot Gold springs. They sometimes have a tendency to cause a slight sewing machine sound because of them being dual springs and the greater seat pressures".
So I hope I don't have to go in and change valve springs as a last resort in quieting this sound down.
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
Well none of the good stuff ac come in yet to continue the work on this project of solving the sew machine sound to with in acceptance.
I email Patriot heads and explained to Gunnar what probles I was having with the other than normal valve train noise and the two sets of different push rods I have tried to limit the sewing machine sound.
This is his reply back:
"The pushrod is probably correct, the source of the notice could be the valve springs. The heads come with the Patriot Gold springs. They sometimes have a tendency to cause a slight sewing machine sound because of them being dual springs and the greater seat pressures".
So I hope I don't have to go in and change valve springs as a last resort in quieting this sound down.
I email Patriot heads and explained to Gunnar what probles I was having with the other than normal valve train noise and the two sets of different push rods I have tried to limit the sewing machine sound.
This is his reply back:
"The pushrod is probably correct, the source of the notice could be the valve springs. The heads come with the Patriot Gold springs. They sometimes have a tendency to cause a slight sewing machine sound because of them being dual springs and the greater seat pressures".
So I hope I don't have to go in and change valve springs as a last resort in quieting this sound down.
Thread Starter
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Hope my lil cam and heads will be more like a regular sewing machine sound.