Obtained the Harland Sharp 1.7 ratio Alum roller rockers. Nice pieces. Went in ok.

Rear part was close to ridge in head and filed it down to give a little more clearance.

No excessive noise or other downfalls.

Steve

Good to hear. I just picked up a set of 1.5's for the new buildup!

I'm guessing this was on the LT4, any before/after dyno numbers?

I have had mine in for a few weeks now. I did notice a small SOTP gain. Feels like the motor wants to wind up a little quicker now.

I tell you what. You guys might write-off the opinion of a drag racer, but if I were in your shoes and looking to operate the motor for extended periods at mid and high-rpm conditions, I would chose only 1 roller rocker, the Comp Cams Pro Magnum steel rockers, non-self aligning, with hardened pushrods and guideplates, 7/16ths rocker studs.

Short of rocker girdles, this is going to be the strongest, most rigid and most accurate valvetrain. The aluminums are fine for most, but there have been instances when they've broken on people, being drag racers. With the different abuse a road race motor takes, I'd want the stronger steel rockers. They are heavier yes, but the actual weight at the valve stem is less due to their ability to remove material and preserve strength via steel. Trunion is bigger too, meaning loads are distributed more evenly. And the hardened pushrods and guideplates would create a very stable environment with little or no deflection.

Its the setup I have, and I wouldn't go any other way.

Actually, I installed them on my '02 F'hawk LS1 motor. The LT4 already has the factory RR. Couldn't resist the nice appearance. too bad they have to be covered up.

I note with interest the opinion regarding the alum vs steel rockers brought out by Chris. I hadn't heard this before and I give it great weight. The other popular RRs, Yella Terror, have had some failures. But I have confidence in HS as they've been doing this for a long time.

When I get the dyno I'll post it. It should be worth around 10+hp.

BTW, our new sponsor "Getspeedparts.com" has a GP going on. Less than I paid thru the LS1tech sponsor. They cost me $319.99 there.

http://frrax.com/rrforum/index.php?act=ST&f=13&t=929

Here's the website for HS:

http://www.harlandsharp.com/bolton3.htm

Regards
Steve

Ah, my post was in regard to LT1 rockers. I'm not really up to speed on LS1 pieces but had a friend who was happy with the Yella Terras.

i also second the Comp Pro-Mags, me and a good friend just did a high-reving 383 build-up using them, the are performing flawlessly. the build quality on them was great, and the price was in the $260 range from summit.

Hell no! While researching my new valvetrain, I've learned a ton from drag racers. I've actually been reading the LT1 Tech section at CZ28.com! Of course things do need to be put in the proper context--shifting at 7K on a stock bottom end, electric water pumps, etc....

Anyway, you perfectly described the set-up I installed last weekend. That's some quality stuff....

And the rocker bodies are warrantied against breakage for as long as you own them. You can get rebuild kits for the trunion too.

I don't want to comment on the Harland Sharp since I know very little about them.....but the average run of the mill aluminum rockers break all the time on the dirt track cars too.

I have a friend that has shoe box full of broken cheap rocker arms....and many are the Crane Gold ones.

And for those not in the know, the OEM LT4 rockers = the crane golds. Same rocker, different color, different stud diameter.

For you guys installing the RRs onto the LT1 motor, don't forget to upgrade the Knock Module (KM) located in the back of the PCM unit. The engine has a knock sensor and its job is to record the "noise" of the engine and send the signal to the computer's KM. The KM interprets the signal and instructs the computer to retard timing when knock is detected.

The OE LT1 KM will interprete the additional noise signal generated by the Knock Sensor (arising from RRs, cam and/or headers & etc) and it will then retard the timing "thinking" that the additional noise is true knock when in fact it is just mechanical noise.

Substitute the LT4 KM for the existing one. GM modified it to account for the added noise produced by the LT4 RRs and higher performance so as to not retard timing w/o true knock being present.

Sold frequently on EBay and elsewhere for about $40. There's a guy I bought one from at a GM dealer for about $35 total. Ten minute swap out

steve

Yeah, I picked up 11RWHP just by putting in the LT4 KM.

LT4 KM: $29.99

http://samtaylor.com/html/parts.html

SD