Heat blued rockers after 50-100 miles....
 

After 50-100 miles driving with Vortec heads, new roller tip rocker arms, cam, and springs, I took off the valve covers for an inspection tonight.

Most of the rocker arms - but not all - have a blued finish that indicates high heat. It was not only exhaust rockers that was blued.
I have not had more then 3500 RPM's during these miles.
Is this blued look normal or wrong? Judging from the ones that are less blued, it looks like the bluing has started at the bottom of the rocker arm.


-The engine sounds and works very good.
-the oil looks very good.
-The oil pressure is ok.
-The rocker arms do receive oil through the push rods.
-The oil remainings in the heads are fine. No particles.
-No over heat problems.
-During rocker arm adjustment, I useed 1/2 to 3/4 turn pre load.
Loosened 3 rocker arms for inspection.
-None of the push rods were bent.
-None of the rocker arms showed wear marks from bottoming down on the studs boss.
-Spring load were shimmed during mounting.

Engine:
Chevy Small Block 350, 93 model Factory roller Block.
Vortec heads
Cam specs: HOWARD'S SBC 305-350 Chevy 270/278 495"/500" 114° Hyd. Roller Camshaft Cam.
Rocker arms are Comp Cams Self aligning, 1.6 ratio roller tip.
Alex's parts Beehive springs for Vortec heads good for Maximum 0,550" lift. Retainers and valve Locks also from Alex's Parts, specially for Vortec heads and higher lift cams (reatiners are grinded off on the underside).

When re-measuring the retiner to seal clearance on a couple of exhaust valves, I found it was only 0,570".
With the 1.6 rockers and that cam the lift sould be 0,530".

I have decided to switch to 1.5 ratio and full roller rockers to lower the heat and to make sure the retainer to seal clearance is enough.

Do you think that will lower engine performance much?

Re: Heat blued rockers after 50-100 miles....
 

:eek:

Re: Heat blued rockers after 50-100 miles....
 

I read the post expecting to see a good answer from Dave and as I scroll down I see the "EEEK!" Funny Dave! I guess the OP's problem is not good.....?

Re: Heat blued rockers after 50-100 miles....
 

I have the same roller tip rockers but in 1.5 ratio. If you search "comp magnum rocker arm bluing" you'll find a few discussions on it. Wonder if mine have turned blue too...

There was an Engine Masters episode about rockers recently. What I took from it is that roller tip only is a waste of time, either stick with stamped or full roller. I think someone mentions something about them bluing as well.

Re: Heat blued rockers after 50-100 miles....
 

saw that as well they had done a comparision test but in fairness the stamped rocker was a howards long slot and not stock. But Full roller was where the power was .

Re: Heat blued rockers after 50-100 miles....
 

Yeah, but still cool to see an apples to apples stamped vs roller comparison. The 7/16" Howards long slots are only around $100 for a set. I wish they also did a standard 3/8" stamped rocker to show what "stock" does and to more accurately compare with the roller tipped ones.

Re: Heat blued rockers after 50-100 miles....
 

I'm sorry...wish I had something better to contribute. And not being a smart ***. I just think I'd be a little alarmed if I saw that. Sounds like its not the first time that issue has been seen. Maybe it's normal / OK. I don't know. I hope to find out by following this thread though.

Re: Heat blued rockers after 50-100 miles....
 

A set of full roller rockers is on its way. PRW 0235002.
I'm not driving the car until then.
IF there is any binding somewhere, despite my control measurments, I don't want to break any rocker studs.

https://www.ebay.com/itm/PRW-0235002...Zalxjs&vxp=mtr

Re: Heat blued rockers after 50-100 miles....
 

How long does it take for the oil to flow out of the pushrods when the engine is started - without revving it?

Re: Heat blued rockers after 50-100 miles....
 

Not long.
I didn't actually take the time when I checked it, but I'll say 10-15 Seconds.

Re: Heat blued rockers after 50-100 miles....
 

10-15 seconds would be fine.

Re: Heat blued rockers after 50-100 miles....
 

Wanted to follow up on this in case anyone was interested since I changed heads recently.

The engine was built with the magnum rockers about 6 months ago, it's not my daily driver, and I don't rev it to the moon very much. The cam I'm running is a modest 211/219 @ .050 so the springs for it don't really have any crazy valve seat or open pressure. My rockers all had some amount of discoloration, some a bit worse than others. A few of them even have what looks like burnt oil. Don't know if it's really a sign of an issue with these rockers, but it sure looks like they ran too hot.

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Re: Heat blued rockers after 50-100 miles....
 

Have you called Comp and asked them about it? That certainly is not something I would consider "normal".

I'll check mine out. I have the non self aligning version of the same 1.6 rockers in my 86 stock LB9.

GD

Re: Heat blued rockers after 50-100 miles....
 

:yup:

Re: Heat blued rockers after 50-100 miles....
 

I sent an email to Comp Cams about mine, but didn't receive any answer.

Re: Heat blued rockers after 50-100 miles....
 

Yeah I kinda just chalked it up as one of those goofy things that's not really any good 95% of the time, like gear drives for camshafts. I don't think Comp is going to care if they're still selling them and we're not the only people to experience it. I'm seeing threads from over 10 years ago of people having this problem or just noting discoloring. Rather have roller or bushed trunnions before a roller tip only rocker, look at what Chevy did with the LSx series.

I went with Crane Nitro-Carb stamped rockers with polylocks on the new heads. I really don't see full roller rockers doing anything for me on this build and didn't want any problems using the stock valve covers. Probably could've just thrown stock long slots on there really.

Re: Heat blued rockers after 50-100 miles....
 

I use those Comp roller tip rockers, and yes they discolor in that area, but nothing like yours.

Re: Heat blued rockers after 50-100 miles....
 

I have used those in the past. Mine behaved similarly. Blue, and some with the burnt oil residue. Yours look a bit worse than mine did but I'm not surprised.

Stock rockers do pretty much the same thing under the same conditions, for the same reason. That part of the Comp rocker (the ball) is pretty much the same thing as stock.

IMO those rockers, or really any other non-roller-trunnion ones, are not suitable for any valve train that's very much more aggressive than stock. There's simply too much force and friction on that ball. The roller tip no doubt helps quite a bit with guide wear, but the ball seat problem remains.

There were reports back in the day of 15 - 20° lower oil temps resulting from a ball -> roller rocker swap. Seeing how hot the ball seats get, that doesn't surprise me in the least.

I doubt there's any material difference in this regard between stamped sheet rubber and investment-cast rocker bodies. If those Comp rockers got heated up like that in your particular motor, the Cranes will likely suffer the same fate. The problem is the fundamental ball design being overwhelmed by the load placed on it when it's forced to go through its sliding motion.

Re: Heat blued rockers after 50-100 miles....
 

Very interesting. Sounds like the friction rockers can't handle the higher lift numbers. I wonder what the cut-off for lift is while still using this style of rocker?

Re: Heat blued rockers after 50-100 miles....
 

GD, I don't think it's "lift" per se, so much as, the overall stress on the ball. Although, in a general way, lift would certainly contribute.

The heat generated by friction would boil down to 2 factors: the pressure (spring load), and the speed that the pivot moves (cam lobe ramp rates & RPMs). Almost any aftermarket cam, especially when critically and enthusiastically test-driven after installation, would easily generate twice as much heat OR MORE at the rocker balls than something like a stock 929. Synthetic oil would help but...

Re: Heat blued rockers after 50-100 miles....
 

Ah yes of course the spring rate.... and the ramp rate that goes with higher lift would of course increase the acceleration. Makes perfect sense.