I will give you great advice.
Call Dwayne Porter, go with his suggestion, and have him order you a cam.
He knows 100% what he is doing and that takes the guesswork out of it.
I have personal experience using his help, and the cams worked perfect.

I just knew this one would come up. Apples and oranges!!

Had em rebuilt once just because they felt a little funny rollen em on my fingers and that was about 6 years ago when I drove it weekly. I drive it less now but what`s funny is the 276 cam mentioned is the cam in my car and it`s got gentle ramps w/low stable spring pressures. When I went 9.98 it had 210 on the seat and drove it that way for several years. ADD a [censored] and I think it`s been closer to to 10 years........

Only downside to the roller is cost IMO.

How so?

For race cars I think smaller motors benefit more from a SR in that a big motor can take more seat to seat duration down low and still be responsive "enough" below the torque peak while at the same time can get adequate .050-up cylinder filling for the heads/peak power RPM from the flat tappet. A comparable flat tappet generally needs more (beyond) peak lift to be comparable so you can get the same effective peak lift duration, and in some cases you can be limited by the steepness of the ramp you can put on a flat tappet. That was (in the early days) a Big part of the reason mushroom tappets were developed.

With a smaller motor it can benefit more from a tighter seat to seat while using the roller lobe to "catch up" at the higher lifts, a smaller motor generally has a narrower powerband to begin with so anything you can do to broaden the powerband window tends to make it more consistent.

my .02 FWIW...interesting thread though...I'm enjoying it

I'm pretty sure those little bottles of ZDDP (zinc) are still available?



I can see the wear particles from the cam & lifters being thrown into the cylinder bores by splash, but how would they get through the oil filter to the crank and bearings?

Nobody's mentioned the old "Mini-Express" mushroom cam/lifters P3690588 (316 adv. @ 0.654) and there's a bigger one 328, 0.690. Lifters are a PITA to change but the few people who have run one have had good things to say about the performance. I think it's around 270 duration @.050. A lot cheaper than a roller setup...

Hydraulic rollers in production engines like the LS7 7.0L that turn 7,000 rpm with a 100k warranty wasn't in anybodies wildest dreams back in the '60s/70s/80/90s. Heck, 10 years ago we would have all thought that this kind of performance was impossible. These are street grinds with over 0.600-inch valve lift too. Sure, solid flat tappet cams can make more peak horsepower at the strip, but it can't touch rollers for the area under the curve and all round street performance. PLUS you can reuse roller lifters as often as you want.

yes i will give Dwayne a call, but when i'm ready to buy.

yeah, but whos making a hyro roller lifter for mopar that can spin 7000+ without heavy springs?

I understand where your coming from with that and i agree, but i do not want agressive ramps that eat up springs. I want longevity in this build as well.

beehives how yah think those engine make 100k without wearing out parts.

The roller Dwayne specc'ed for me was in the car 8 years when i sold it( and I raced it way more than you, and street drove it all the time) with only 1 spring change in all those years.
Never a single issue.

how many top performance cylinder head shops you know that are suggesting and using beehive springs? Not too common around here. I even asked Ryan Johnson about beehive springs and he wanted nothing to do with them. Maybe there more common now but i hear nothin g of them around here.

Cool? Ill be talking to him soon.

Been available for years.

http://www.hughesengines.com/TechArticles/1beehivespringsretainers.php

But anyways it sounds like you already made up your mind, good luck

I will say I was on the beehive bandwagon for a while then got off it hard. Had way too many failures. If you call PAC and ask them for a spring for anything with what I would call a performance lobe, they don't suggest beehives. I was burned two years ago with beehives and that will be the last time.


Just becaus the OE's do something, doesn't mean it translates into the performance world.

I just broke in my SFT with 145 on the seat and 345 over the nose (.620 gross .606 NET) and used Torco break in oil with no issues. If you get it running and th lifters spin they won't go flat. I never use additives. I want th guy who designed the oil to put in it what he thought best.

BTW and FWIW I will use Torco 5w30 synthetic when it comes off the dyno.

You plan on spinning 511ci 7000+rpm on the street?
Why?

For some reason Mopar guys love over-reving their engines and doing wheelies that break stuff and oil down tracks.

My 517 routinely spins 6800+, went 7200 more than a few times. It has a Bullet 264/268 @.050 Hydraulic roller with the Crane lifters....BUT(!!!) These Heads also have the Race W2 Style billet one piece Shaft hold downs (Chapman stage VI's) which are much stronger and more stable than a Cast-In-Head Pedestal....and ports that are happy to feed it up there. Never rev'ed it higher than that...but with the new ported 337 intake it may want to go even a little higher.

I'm not sure it would rev that high or that stable with cast-in pedestals....I can't say 'cause I never had a 500" BB willing to rev this high. I do know the fact that they are Hydraulic rollers don't seem to hold it back at all, this one rev's just like a Solid roller. I think the HR (or any valvetrain) ability to rev has about as much to do with geometry and stability (and minimal oscillation) as it does with sheer mass.

all else being equal one would think a low deck might rev a little higher than an RB....the pushrods are ~3/4" shorter and proportionally a bit lighter.