All_Motor_C5LS6

Which Roller Rockers would you recommend on a H/C 346cid setup? Harland Sharp, Jessel, Scorpion or Yella Terras?

silver408z

What heads are you running? If aftermarkets arent recomended like with the trick flow heads then stick with your stock rockers. There is lots of research and threads on this topic. The stock rockers have one of the best swipe patterns and are light. The only problem people have with is the needle bearing coming. Comp Cams sells an upgrade kit for the stock rockers that prevents this and it cost about 1/3 of after market rockers.

I personally have Harland Sharp but I have trick flow heads and after market rockers are recomended for them. Alot of people like the Yella Terras and Jessels can be really expensive. The main thing about them is setting them up correctly.

FKING1

Have Jesel 1:8 shaft mounted on my modded 2000. Ported stock heads & cam. Over 10 yrs.
Need to grind a bit of clearance in rocker covers , but, no biggie.

All_Motor_C5LS6

TSP LS6 stg 1s, I've been running them for over 4 yrs now without an issue. I'm looking at freshing up my rocker arms, although they are still in great conditon.

0331MARINE

Theres really no point in doing after market rockers.

tsts

I found that my HS roller tip rockers helped quiet the valve train noise over stock rockers. 16K on the HS and no issues/adj. yet, they're O.K. with me so far.

vettenuts

I would disagree with that statement and it is the whole reason aftermarket heads recommend roller rockers rather then stockers. I tried to get my stockers to work on both Dart and AFR heads, wipe pattern was very wide and uncorrectable. My Yella Terra's, properly set up, came up with a pattern perfectly centered and 0.045" wide which will help minimize side loads on my guides. Here's what Tony thinks: Link

Gray Ghost GS

+1 for 1.7 Yella Terra Ultralites

rustyguns

do you guys know why the stock rockers don't have rollers? I am pretty sure it is so the valve spins. and the reason most after market guys have the roller tips is because that is the cheapest and strongest way to mount a tip on aluminum.

the stock rockers are quite good and good for the motor. if the swipes were bad on the valves, it may have been assembled wrong or abused.

who would abuse a corvette?

but wth massive cams and big *** valves/heads, you need aftermarket

Last C5

+2 for the Yella Terras

chevy406

You have that rather backwards my friend. The stock rockers are no doubt a lot cheaper to manufacture with a flat tip than adding a roller bearing tip.

Until you have marked the end of a valve and rotated the cam through it's lift cycle, you may not fully understand what Vettenuts is talking about. It doesn't take a large cam (i.e. my 224/230) for side loading with stock rockers to become a real problem. Not saying that stock rockers aren't strong - just that the flat tip absolutely will not give you a tight contact patch on the valve tip once you increase cam lift.

Absolutely incorrect assumption. I can assure you that from the posts I have read from Vettenuts, he is extremely detailed and meticulous. I have also measured the swipe between the stock rockers and my valves after my cam swap, and I quickly purchased a set of full roller rockers. I now have 66,000 miles on those parts, without any problems.

I would encourage you to actually pull a couple rockers off, mark them, and then come back and comment in this thread.

and to the OP - any of the rockers that you listed will be quality pieces. Find a good price and buy them.

Jim in Mich

+3 Yella Terra

0C_Williams@RPM

for what it's worth, here's what I've seen over the years...


1 - The stock rocker arm is excellent- especially with the above mentioned Comp Cams trunnion upgrade

* Rigid and lightweight
* Low Cost
* Carry High RPM without "nosing-over"
* Reliable and easily available

2 - Lower Cost Roller Rockers

* many will nose over above 6500 RPM ( tip weight)
* Most are not adjustable
* Some require a taller valve cover or valve cover spacer
* Available in offsets and various ratios

3 High end roller rocker arms - Jesel, Crower, T&D -

* Available in all ratios as well as adjustable and non-adjustable.
* Available in any offset or ratio
* Require a taller valve cover or valve cover spacer
* May require cylinder head machining to mount

All_Motor_C5LS6

What do you mean by "nosing over"?

C5XTASY

What do you think of the SLP 1.85s? They are the stock rocker arm with the Comp trunion upgrade installed by Comp and made into 1.85 rockers.
Ed

0C_Williams@RPM

When this occurs the HP curves simply "fall off a cliff" vs a gradual flattening. When valve train related this will generally occur within a few hundred RPM of peak power.

0C_Williams@RPM

No problems here. Just bear in mind the physics and geometry associated with increased ratios and don't get greedy - i.e., cracking open valves well past lobe designs or cylinder fill capability.

MTPZ06

What springs are you running?

robz

Jesels are the best hands down.

A cheaper alternatine is a yella terra lightweight rockers.
My 346 h/c made peak hp just over 7000rpms and lost about 10 hp up to 7500rpms.
Swipe pattern and geometry is important.

C5XTASY

I have a Comp Cams XR269HR cam with 918 springs...valve openings are .525 and .532 with the XR lobes. As it's a low-lift, mild cam, I think I'd be all right. Comp thought I'd be okay. What do you think?
Ed