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MP 528 solid. What hydraulic cam would be the equivalent?

Kern Dog

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I'm just spitballin' here but I am considering a camshaft swap.
I'm running the Mopar Performance 528 solid in my 440/493.
It makes adequate power, great vacuum and idles pretty good but the wide lash and the clatter is getting to annoy me.
I have a Lunati solid that I ran for awhile that was much more rowdy but it didn't clatter like this. The Lunati specs were as follows...

Lunati specs.JPG


The MP 528 has a lash of .028 intake, .032 exhaust. I tightened up the lash to .025 Int .028 exh and it still is too noisy for me.

I liked the power of that Lunati but it did idle a bit choppy. I still have it and the lifters are all in order. The power brakes didn't like the cam though. Idle vacuum was low and I had to run a vacuum pump.

I'd consider a hydraulic flat tappet just for the quieter operation but don't want to go backwards in power.
I've considered a switch to a manual brake setup. This would negate any drawbacks of a cam that produces low idle vacuum.

I have read from some guys that ran the lash tighter on this 528. I'd do that if I knew that there were no damages related to that.

Suggestions?
 
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I stumbled upon THIS thread....
https://www.forbbodiesonly.com/moparforum/threads/mp-solid-ft-cams-and-their-lash-specs.180433/

Several respondents did tighten up the lash with no ill effects. The only one that advised against it is Andy F.....He didn't state why, he just stated :

"The mfg recommends the lash based on the ramp design. I wouldn't recommend running a cam at anything other than what the mfg recommends. If you want a tight lash cam then buy one. The older cams typically had a lot of lash. Cam mfgs changed the ramp designs over the years and now you can buy tight lash designs if you want."
 
There is NO harm in reducing lash to 012/014. Or anywhere in between if you want to experiment. Think about it: to get to 028 it has to pass 012....
The tighter the lash, the worse the idle quality & idle vacuum. You may lose some low end depending on how big the cam is for the combo & you may gain a little top end. You would need to subtract about 15* from the 050 numbers for that big lash to equate [ roughly ] to a hyd lobe. I believe the 528 is about 241@050, so you would need a 226 @ 050 hyd cam.
I would stick with the 528 & tighten the lash.
 
I get that, it would be a NO cost test to see if it helps.
Thank you.
 
Some cams are made in tight lash designs. I have an Stx-22 (590) solid cam... I know the there is an equivalent Mopar Perf solid 590 that is the standard lash spec. Unfortunately I can't answer to any running difference in characteristics. Mine is made by Racer Brown. I hear that's still one place you can call and get real answers.
 
I've always heard if you want to see what more duration cam does tighten the lash down. Loosen to see what less duration is like.
 
I ran couple different MP cams over the years and neither compared to the power and responsiveness of a Hughes cam. Their customer service is good at suggesting a cam that fits your needs.
 
Not sure if you would consider a solid roller. I'm running a low lash grind from Cam Motion (.010 hot) and find it to be quiet.
 
Roller camshafts seem to carry with them some low rpm drawbacks, right? I've read that extensive idling is hard on them due to minimal oiling to the roller wheels. Cruising and low rpm freeway driving would figure into that, right?
I am probably going to close up the lash a bit and see if enough clatter goes away to make the cam tolerable. The performance is fine. My Lunati ran much quieter with the tighter lash.
 
I think certainly if you get into the aggressive range of things.

If you aren't running super aggressive ramps/very high valve lift not sure why a roller lifter wouldn't live with the same oiling as a flat tappet.

Lifter design varies greatly. The ones I use have direct pressure oiling to the axle.

Many do not, which I think would require/benefit more from a higher idle speed to increase splash oiling.


But yes, why not just try to sneak up on lash and see if quiets up before anything else.
 
Remind us if you are running aluminum heads and are setting the lash hot or cold.
 
These are Edelbrock aluminum heads and I do set lash cold. To me, that is more consistent than warm since the engine seems to cool off faster than I can lash everything.
Maybe I'm over-thinking it. I don't know how fast a warmed up engine takes to cool off to the point where the settings make a difference. I've always chosen to set the lash on this engine before it has been ran that day. I'd certainly welcome any advice on how accurate a "hot" number would be on an engine that was shut off and let to sit for 30 minutes in 80 degree weather. That may be hard to determine though.
I subtract .006 when lashing. A .020 hot spec setting gets set to .014 cold.
 
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I just set the lash and warmed up the car.
.016 intake, .018 exhaust COLD. This equates to .022 Intake, .024 Exhaust when warmed up. The original spec is .028-.032.
It is much quieter but I did have 2 intake valves that had a lot of clearance. That has me worried....do I have 2 lifters going bad or what? The oil has no sheen to it. It now idles evenly but the rpm did drop a little from what it was before it started running rough.
I wanted to blame the gasoline but wanted to see what else it could be.
Tighter lash= bigger cam, right? Maybe the lash being tighter draws more fuel and air, requiring the curb idle adjustment?
 
That has me worried....do I have 2 lifters going bad or what
Maybe you are really considering a cam change for more obvious reason.... i`d put a dial indicator on the two lobes that were wide lash and see where you are at. Maybe a compression check to see what kind of variation you have between all cylinders would also be helpful.
 
My experience with American V8 engines with alum heads using rocker studs is that the hot/cold lash difference is 0.002/3". With engines using rocker stands, this might increase by 0.001".
 
I drove a bit and it ran better but not like it should. Some detonation, down a bit on power and it wasn't quite as smooth as usual.
Back at home I pulled the intake and valley pan and found at least 3 lobes going bad. One was almost gone entirely.
This was with EDM lifters and high zinc oil. I even added the Comp Cams supplement at each oil change.
Back in 2006, I went through 2 Comp Cams hydraulic sticks back to back.
In 2008, a MP '508 went in my 360 Duster.

The strange thing is, it ran fantastic to Los Angeles and back. It is as if once it wears through the hardened surface, it wears away really fast. I only drove around for 30 miles or so on Saturday and about the same today.

Time for a roller cam?
 
FT cams do not have a hardened surface, unlike steel roller cams. Hardness is the same throughout the metal.
EDM holes are useless when the lifters are made of crap-anium. And that is the risk you take with lifters made in the last 20+ yrs.
I only use original factory lifters [ or aftermarket lifters made prior to 1995 ]. If used, I have then re-faced & they are then as good as new. No failures in 40+ yrs.
 
No hardened surface? What about "Parkerizing"?
These lifters are Howards, a quality brand.
 
Parkerising is a process that impregnates the pores of the metal surface with lubricant; for initial lubrication for the break-in period. It has no affect on material hardness.

No cam company makes it's own lifters...or ever did.
They buy from one of the companies that make lifters. They then put them in their own boxes...& charge accordingly. My understanding is that there are only 2-3 companies still making FT lifters. The problem is with the metallurgy of the metal more so than the machining process.
 
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