General Category > Quadrajet Carb Talk and Tips

vacuum at WOT

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Miles:
I bought that SP in 2011, took me a year or so to get the thing in the car, but I've been wanting to change it out for a larger cam ever since. Was going to run the OF or something close, but change to a solid roller as my comp hydraulic rollers just wont hold oil. I'm on my second set of the 857-16s and they are just no good.
I was going to put solid Crowers on the hydraulic roller SP but that is not big enough, so while I'm changing the camshaft anyway I suppose a solid roller grind makes more sense as it [I think] has softer lead ramps?

Yes Quench is an important factor, I have mine zero decked with flat tops, just the thickness of the MLS gasket for quench distance.

What was the ICL of the 236-245 that went into the 455?

I've been putting off changing the carb and the camshaft for a couple of years but as I found some metal specs in the oil filter yesterday, I'll have to pull the 428 out and tear it down, both to find the cause and clean the entire engine. That did not make my day!

Cliff Ruggles:
We've seen troubles with the retrofit HR lifters as well.

My own engine uses the Old Faithful camshaft and Crower HIPPO solid roller lifters set at .005" lash.  It has been flawless since 2009 aside from the PRW roller rocker arms that failed and put a ton of metal into my assembly.

I swapped them out for Crower Enduro roller rockers but a bit too late and need to take the engine down and re-ring it.

The PRW roller rockers wear out between the pins and rollers, and we have since removed every set we used or sold and replaced them.

The OF clone we used in the build mentioned above had the ICL at 110.....Cliff

Miles:
Thanks Cliff,
Lifters and now the rockers? Crap, I also have PRW rockers. Do you know the part number of the ones that failed or is all PRW rockers that are failing?
Al

Miles:
Mine are stainless PQ. I see Dave no longer lists them on his site. Maybe for that reason.

Cliff Ruggles:
Mine were the stainless steel full rollers.  They look like very good parts and we've had no issues with the needle bearing part of them. 

Every single set otherwise developed a LOT of play at the pins/roller tips.

All of those engines also showed a LOT of very fine metal on the magnetic drain plugs (Morroso pans) that we were unable to discover a source for initially.  At each oil change the drain plug would have a teaspoon or so or metal "toothpaste" on it, coming directly from the rollers and pins of the PRW rocker arms.

I sent my set back to them for analysis and they admitted that the pins had a poor finish on them back in 2009 when purchased, but they had since corrected that issue.  Even after they told us that we've seen quite a few others have the same issues and some of those rockers were very recent production.....FWIW......Cliff

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