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Best bang/buck SB shaft rockers for 500# plus springs?

Posted By: Streetwize

Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 08:18 PM

Harland Sharps, Hughes or Comp Pro Mags?

I know the T&D's would be best and if I were racing every week-end I'd probably opt that way.....but of the 3 I've listed which are best and (more importantly) why?

I'm leaning toward the Hughes right now because I've had good luck with their BB rocker gear before.
Posted By: MattW

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 08:36 PM

Quote:

Harland Sharps, Hughes or Comp Pro Mags?

I know the T&D's would be best and if I were racing every week-end I'd probably opt that way.....but of the 3 I've listed which are best and (more importantly) why?

I'm leaning toward the Hughes right now because I've had good luck with their BB rocker gear before.



I have a brand new set TD for INDY 360 CNC heads for sale. Don't know if this would help you or not.
1.65 ratio. Matt
Posted By: Anonymous

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 08:55 PM

Marsh Perf 336 283 0800 Harlands and race them until you retire then sell them.
Posted By: 340B5

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 09:16 PM

If rpm is 6500 or under I would use the comps. The 8620 steel they are made of is tougher than an anvil in the desert, but they're heavy and I don't believe comps 'over the nose" claims about the weight. Mass is mass and it has to accelerate and decelerate in a controlled manner. Higher rpm and I would use something else like the Hughes. I personally don't trust needle brgs not to break,but that's just my
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 09:26 PM

I made an easy test hit the new Bullet cam shifting at 5800 and it felt like she wanted to go 6800+ , that's what I'm worried about.

The Standard Comp SS Mags are way overtaxed now.... I think Comp only rates for like 350 open, but I know they were holding up fine with the milder "endurance" Cam Motion that was 261/268 @ .050 and .585/570 lift , This new cam is 260/269 but much more aggressive lobes .668/.645 at the valve on 1.5's so I gotta make the change or cry about it later.
Posted By: mshred

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 10:49 PM

I would go with the Hughes... I took them to 6800 in my flat tappet motor, and close to that with hydraulic rollers. Had them for a couple of years, and never had any problems with them or their adjustment. I think they are a great piece
Posted By: dusturbd340W5

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/13/14 11:36 PM

Quote:

Marsh Perf 336 283 0800 Harlands and race them until you retire then sell them.



Harland Sharps all the way out of those 3.
you will have years of trouble free use.
Posted By: Locomotion

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 12:32 AM

I recommend Harland Sharps as well. I know they make a pretty thick shaft, which is obviously important to minimize flex with higher spring pressures. While 500 lbs isn't a heck of a lot, it's better to have "more" than what you need as extra insurance. I've never run more than 400 lbs open, but I ran them for many years with a lot of abuse years ago in my W-2 bracket Challenger. I was glad they legalized them for IHRA and NHRA Stock. I'm near 400 but may eventually go higher. (Relatively low lift, but very long duration & steep ramps with Schubeck/Smith style flat composite hydraulic lifters.)
Posted By: DJVCuda

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 12:55 AM

I spun my ultra pro mags to 7 grand

They were lighter then the Harland sharps and the geometry was a ton better.
Posted By: Cab_Burge

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 02:45 AM

I bought the Hughes 1.6 cyro treated with the .4?? offset for my BB with Eddy Victor max wedge heads, I broke two of the stock adjusters(two different races ) and ate the rockers up also, of course. I then bought a set of Manton heat treated adjusters, $200.00 + and haven't had any troubles so far with any more broken adjusters I run around 275lbs on seats and 650 lbs opened, I ran the same springs on Duster motor and never broke a stock Harland Sharp adjuster Go for the best you can swing now It never hurts to have more than you need on many speed parts in motors that are raced, correct BTW, I saw about the same amount of rocker ratio differences( .030 lift varinces ) at the retainers on the T&D as I did on the Harland Sharps, I like and use Harland Sharps more now
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 03:51 AM

All good advice, thanks everybody!!

I think Vic told me there's as much as .040-.045" lift loss on a 59 degree smallblock due to the bad geometry/lost motion of the pushrods.of that's the case you almost need a 1.6 to net the theoretical 1.5.....unless the rocker ratio compensates for the lost motion to give you the true lift at the valve.

Need to bone up, never gave it much thought in a while...
Posted By: FlyFish

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 01:27 PM

I would go with the comp pro mags. I tried to fit the Harland Sharps on my motor a few years ago, but they would not clear my 1.54" springs (not even close). My old style comp pro mags clear fine...but they are the old ones that are not bushed, so they can't take much more than my current 460# spring pressure without galling the shaft. With the new comp pro mags they fixed this issue by bushing them.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 04:11 PM

The only downside I see with the Comps is I'd have to get all new pushrods

I've had good luck with both the HS and Hughes before
Posted By: dizuster

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 05:06 PM

Quote:

All good advice, thanks everybody!!

I think Vic told me there's about .040-.045" lift loss ona 59 degree smallblock due to the bad geometry/lost motion of the pushrods.



I just checked mine when I put it together... It only lost. 014" with a 3/8" pushrod and 380 lbs open.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 05:37 PM

dizuster,

Which rocker gear are you using?

Imagining the variables involved (lifter body/type, cup height in the lifter, Pushrod length, rocker ratio and lateral motion, etc) it's hard to get my head around it being <.020"

I'm not sure the Harland Sharps are going to clear my springs and it looks like the Hughes are only good for 1.5" diameter springs.

I'll get with Hollis and let him do some cipherin'
Posted By: Locomotion

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 06:15 PM

The downside is that it will cost more, unless you can get most of your money back from your current springs. But have you researched to see if there are any beehive springs that would be suitable for your application? That would solve the clearance problems with any rocker set-up you decide on.

FWIW, these are the heaviest beehives I've been able to find:

PAC-1427

Comp Cams 26056-16

Lunati 74855-16

Bottom line is I guess my suggestion wouldn't help.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 07:08 PM

Springs + Ti retainers = probably more

Related note, Has anybody tried applying any type of thin film lubricant coating to rocker shafts?

Just curious, seems like if it would help reduce heat in a piston pin, it would help a rocker shaft
Posted By: BradH

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 07:17 PM

Quote:

The only downside I see with the Comps is I'd have to get all new pushrods


That assumes that whatever brand of rockers you're looking to replace happens to use the same length as one of the other brands you're considering. I know from mocking up a bunch of different BB rockers one time that only 2 out of 5 brands were close enough dimensionally to be able to actually share the same pushrods. All the others were going to need something w/ different lengths.

Quote:

I've had good luck with both the HS and Hughes before


I like Hughes, not a big fan of HS, but think the Comps are probably the best choice from what I've read above.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/14/14 10:25 PM

What about the Mancini's (which are allegedly made by HS?)
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/15/14 03:50 PM

BTTT

Wanting the 411 on the Mancini rockers
Posted By: BradH

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/15/14 06:17 PM

HS w/ bushings instead of needle bearings. If you like HS, they're less expensive and have fewer moving parts.
Posted By: Locomotion

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/15/14 06:28 PM

I believe I heard that they are aluminum against the shaft or bushed. But even with a bushing, the "body" strength may be even stronger than regular HS rockers with the caged needle/roller bearings because the body may not be machined as much to install them. (If they use the same body.)

I also noticed that the shafts are "hard chromed" which may indicate that they are comparable to what Mopar & Crane sell for their ductile iron and/or aluminum rockers. The regular Harland Sharp rockers are advertised as using "heat treated, heavy wall rocker shafts."

May have to call Mancini for a wall thickness comparison as well as what their assemblies are rated at/recommended for.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/15/14 06:34 PM

Leaning toward the Comps right now, I have fairly fat springs 1.53" IIRC. Hate having to change pushrods though.

I did notice that when I had the old Cam motion Cam which was designed for the IROC 358" Motors, the #2 and #4 cam journals were grooved and they moved plenty of oil to the top. I have an 8 quart Milodon Dragster pan on it so adequate volume/baffling/uncovering the sump was never an issue even with the extra oil up top.
Posted By: BradH

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/15/14 06:34 PM

Quote:

I also noticed that the shafts are "hard chromed" which may indicate that they are comparable to what Mopar & Crane sell for their ductile iron and/or aluminum rockers. The regular Harland Sharp rockers are advertised as using "heat treated, heavy wall rocker shafts."


Good point I hadn't considered; the Mancini "budget" kits may not use the high-end HS shafts, which would be a downside for 500# open pressure usage.
Posted By: Streetwize

Re: Best bang/buck SB shaft rockers for 500# plus springs? - 10/16/14 02:40 AM

I went with the Comps this time, i had a 100.00 Amazon gift card from Christmas I almost forgpt I had
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