[chuckies76ta]

Hi: I'm wondering if anyone who was running PRW 1.5 Roller rockers

part # (PQX-0245501) changed them out to another brand and your pushrod length was ok.? Theses are the PRW Stainless Steel ones.



I understand push rod length needs to be checked regardless. I'd like to go with a more proven 1.5 Rocker good for 600 h/p. 150 seat 400 open springs lift around .600. I'm using Crower on two engines, but very expensive. These are for another engine.



Thanks.

[jonmachota78]

Its been a few years but i did go from PRW 1.65 to harland sharp 1.65 with OF cam. Rechecked pattern and pushrod length 1/2 lift method. It was slightly different but not enough to warrant new pushrods. Its been running fine FWIW

[chuckies76ta]

Thank you. I appreciate the info.

[punkin]

I've got Harland Sharps on my old 455. It's got an Erson mechanical cam/lifter set up and a lot of street and strip miles, no issues, about 22 years now. I would put them in my new motor but I need 1.65:1 whereas the HS are 1.5:1. Can't get over how much the prices on these things have gone up but then again, if you only build a few motors over a lifetime hard to see the creep in costs.

I've hears mixed reviews on a number of the PRW lifter types but nothing about their stainless. Let us know what you end up with.

Good luck.

[n20ta2]

Im with you on this, Butler reccomended the prw ss rockers but im not happy about using thwm long term after hearing a few past stories. Probably replacing mine this spring.

[chuckies76ta]

See that's the thing, I'm like you guys, hearing a few past stories. We ran them for lots of years and still no issues with them. Hmmm Thanks
I remember Cliff posting about them sometime ago.. Will try to find it.

[chuckies76ta]

These look like nice rockers. Good up to 700 spring pressure. https://www.compcams.com/ultra-gold-...1-5-ratio.html
I have run these before. there are nice rockers. https://www.summitracing.com/parts/c...1/make/pontiac

[Cliff R]

I installed a set on my last 455 in 2009. They were nice looking parts, near mirror images of the more expensive Crower Enduro roller rockers.

They were mated up to SD's Old Faithful cam and CNC ported KRE aluminum "D" port heads.

The engine ran fine initially. I was running my first "hybrid" set-up with Crower HIPPO solid lifters on the SD HR cam. I ended up lashing the valves at .005" after trying slightly looser settings. At the first oil change I noticed a big dab of metal "toothpaste" on the magnetic drain plug. Nothing alarming at the time, just figured some fine metal from the initial run-in and couple hundred miles I'd put on it.

I changed the oil again about a year later and re-lashed the valves. I noticed some slight variance in the lash when sliding the feeler gauge between the valve tip and rocker arm roller, but didn't pay it much mind.

Once again a nice dab of metal "toothpaste" on the magnetic drain plug.

The engine was pretty quiet initially but started developing some "ticking" and valve train noise. It got worse the more I ran the engine so I removed the valve covers to take a look around. This time I had a tough time adjusting the lash so I removed the PRW stainless roller rocker arms. They were starting to wear pretty hard betweent the rollers and pins that retain them. Some were out as far as .015" so I removed them and sent them back to PRW for inspection.

They admitted that they had some problems with poorly machined pins and wear in that area but claimed to have corrected the issues.

I didn't get the rockers back or replacements for them so went to Crower Enduro rockers. After the change not the first bit of metal on the drain plug and ALL the valve train noise was gone.

We had used another set of the PRW rockers on a 455 built about a year after mine and all those were wearing out in the same manner so we replaced those as well.

I'm not sure exactly when PRW corrected the issues but we never used any of those rocker arms again. Keep in mind when you read that that if you didn't have a solid lifter set-up and/or magnetic drain plug it would be a LONG time before you'd discover the wear between the rollers and pins. I suspect that there are a LOT of sets out there wearing out in that area and putting fine ground up metal into the assembly and the owners don't even know it......FWIW......

[n20ta2]

Thats exactly the experience im leaning on, thanks for reposting it. Im running 1.65 on a fairly rowdy hydraulic roller and highports. I'm afraid its a recipe for disaster.

[25stevem]

From what I have seen from a friends motor and story’s I have seen I would not use those rockers or Scorpions.

[chuckies76ta]

Ok guys. Thanks for posting the info. Can we get some replacement suggestions please?

[25stevem]

I can’t see how you could go wrong with Harland Sharps.
There a tad on the heavy side due to there mass, but that’s what makes then stout, but with 400 open pressure your not likely to spin things up more the 7K anyway.

[srmmmm]

I used the 1.5 ratio Comps. Engine builder (Len Williams) said they installed fine, but the poly-lock nut is very tall. I had to add the 3/8" aluminum spacer with two of the 5/16" rocker cover gaskets to get enough clearance with my M/T rocker covers.

[n20ta2]

Im going to use either the crane golds or I might bite the bullet and go with the crower enduro. There over 800 for all 16 though.

[chuckies76ta]

Originally Posted by n20ta2

Im going to use either the crane golds or I might bite the bullet and go with the crower enduro. There over 800 for all 16 though.

The Crower are probably the best out there.

[n20ta2]

Originally Posted by chuckies76ta

The Crower are probably the best out there.

Was thinking the same thing, probably wont ever need another set.

[chuckies76ta]

I have them in a 468 and a IA2 engine. They maybe hard to get. I see not available lots places.

[GTOLou]

Have had a set in my hands - chinese made?? I think and stories here and just hand-held quality. Never ran them. Sold em.

Now, I've run and still run multiple sets of scorpions. I just have not had a single issue w/ them. Just MHO.

[Cliff R]

Ran ONE set of Scorpions and cracked 13 out of 16 of them. They didn't fail completely but they were a ticking time bomb.

I was being kind about the PRW's above but the failure rate was 100 percent and PRW didn't replace them. Not surprising as with most of these parts you get a really good "Arkansas Warranty" when you buy them: IF you break them in half.....you get both halves!.....LOL

Anyhow, we do NOT get reliable feedback on most of these "high performance" parts. This simply happnes because most of these cars won't get but a couple thousand miles put on them in the next 5-10 years.

When it comes to roller rocker arms the ONLY ones to date I've not had issues with where Crower Enduro, Crane Gold Race and Harland Sharp. For all the others we've put in service they either cracked, broke, or burnt up the needle bearing or roller end of them.

I see the SAME issues with other parts commonly used in these engines and have responded accordingly. I completley quit using "double roller" timing sets for the same reason. ALL of them failed or get WAY too loose for my liking, and some in pretty short order. I know, I know, about the time you tell someone that your Rollmaster timing set failed in a couple of years in your 455 a dozen folks come on and tell you they have 250,000 miles on one and it's tight as a banjo string.......FWIW.......

[chuckies76ta]

Thanks Cliff for the info.