I had been planning on replacing my stock rockers for quite some time and finally got around to it today. Two reasons I wanted to do this: 1) To quiet down the signature sewing-machine valvetrain sounds that emanate from the engine bay due to the heads/cam and, 2) as a preventative to the needle bearing fallout many have experienced and cited in a GM TSB.

I ordered a set of Harland Sharp 1.7 ratio roller rockers from a local speed shop for a great price and got them yesterday. The Harlands have gotten great reviews from lots of guys who use them and haven't been cited for any issues that I could find compared to a couple of other aftermarket roller rockers I'd researched. Plus, they cost considerably less and the quality is excellent. This morning I pulled the stockers and put these puppies in. I had to clearance the #7 exhaust rocker slightly due to a potential interference just at the corner with the casting (I have the 5.3 L). Other than that, they fit nicely.

I almost did a stupid thing installing these. I didn't get a set of instructions so I initially left the rocker seat strip in and didn't use the pedestals that come with them. Realizing something was amiss when the pushrods had too much clearance, I called FFHP (awesome f-bod tuner guys) and they straightened me out on how the pedastals were positioned and the stock strips eliminated. After fixing that, I torqued it all down and cranked her up.

It was very noisy for the first few minutes until the lifters pumped up and the rockers were thoroughly oiled then it quieted down very nicely. The sewing-machine sounds were considerably quieted. It sounds and runs great. Here are a few pics:

The kit contents








Clearanced with a Dremel tool


No more interference

 

Sweet Ed.

 

i had had some Harlands on my first V8 i built many yrs ago
nice to see a full roller set for the LS1
already planned on heads to complete my cam and gears, but just might have to throw a set of these to compliment the entire package

 

Nice job ED !!! Now that it's over, what's Next?

 

Yup, I've got a set waiting on the shelf for my AFR's and cam project in a few weeks. I was wondering how they would work quieting down the valve train. I'm going to be using an XE-R cam, so I was hoping they would work well. BTW, did you get that 10-14rwhp increase they advertise?

 

Thanks, E-T. Not sure what's next. But I'll let you know as soon as I know.

AFA hp gains, I doubt I'd be able to detect that small a change without a dyno but I'm sure the benefits of reduced friction are there and the reason the sound is diminished.

 

Wow Patches! Those are purdy!

 

They look every bit as good as the Yellas. Best I cant tell online they are:

http://www.jegs.com/cgi-bin/ncommerc...26&prmenbr=361

 

Almost a shame to cover them up they look so good. Any benefits to installing on a stock LS6?

Tom

 

Patches,

First off, they look great!!

Any chance we could find out who you ordered from and what you paid? Reason I'm asking is that I'd like to pick a set up. I previously had a set of Yella Terra's (got them right after they came out) and after installing them, my car actually ran *slower* than it did w/ the stock rockers. I lost HP on the dyno and could feel it on the street. I put the stockers back in and all was good. I've read that the Harlans do not suffer from this syndrome because they are lighter than the YT's, different material, etc.

I'd like to try a set for the reasons you mentioned... I've done just about everything else to the motor... might as well do these...lol!

EDIT: Oh yeah, did you just slap these guys in and torque to 22lb/feet or what? Just curious if you had to shim them any. What length pushrod do you run? I've got the 7.400" w/ a TR224 cam.

Thanks.

 

Also wondering if the install required shims...or any type of measurements besides torqing them down?

 

 

Tom: There are claimed benefits for swapping this type of rocker in but I can't personally say if a stock motor would benefit noticeably. The LS6 valvetrain already has considerably less mass than the LS1 so I would think the benefits of rocker friction and mass reduction would there.

AllCammedUp & 99SilverC5Coupe: I did a direct swap - no shims. I'm running the 5.3 L heads that were milled .030" with 7.350" pr's and a 229/229/112 cam with .578"/.578". I installed them just like you would the stockers and torqued them to 22 ft. lbs. I always use the sm's procedure by starting with cyl. #1 at tdc even though I know a lot of folks don't. Also, I manually rotate the engine several times to check for interference and recheck the torque before I button it up and start the motor.

Remember that one of the reasons you may lose power using this type of rockeris the extra mass the roller tip brings with it. I haven't dynoed so I have no idea what these are giving or taking in terms of power.

As far as supplier, I would just order from Nate at:

NastyPerformance.com
847-458-4858
Nate@nastyperformance.com

If you factor in shipping, his price is as good as I got from my local shop.

 

They are pretty.

 

Nice...
Im only a little surprised when you dremeled the edge...
...that you didnt just finish them all off and take them all to a high polish

 

Great Choice, Patches!!

I bought these rockers last winter and installed them this past April. They helped quiet down the valvetrain quite a bit and I felt better swapping them out since I'm running a H/C motor. I had no clearance issues with ported stock heads and they handle the abuse quite well. I can't verify HP increase or loss because I haven't strapped the car on a dyno yet. I did the swap mainly for piece of mind. I felt the stock rockers with a high lift cam (224/230 .580/.571 112lsa) would eventually give out. I would recommend these to anyone wanting a different set of rockers. The money you save for the quality product you get is worth it alone.

 

pics tell the whole story.