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Rocker arms

NorthWestFloridaBoy

NorthWestFloridaBoy

Well-known member
I want to replace my stock, stamped steel 1.5 ratio arms with some full roller 1.6 models and I see them in aluminum and steel, which ones are better for DD airboating?
 
Go with the 1.6 Harland Sharps they will give you the most quality for your dollar. I have ran them with over .800 lift and over 8,000 RPM with out ever having a failure. Stay away from the cheap PROFORM heck their fulcrums are sloppy straight out of the box!
 
OK...Here's the real skinny...I'm gonna have to make a few assumptions about your engine/cylinder heads based on what you've posted. First assumption....You're running a Small block Chevrolet. second, the heads are still "stock" with press-fit rocker studs as well as stud bosses. Now a BIG assumption is that the engine has iron heads rather than aluminum.

Now with all the ASSumptions I've made, you will love going to a 1.6 ratio rocker and even better...A 1.7 from Scorpion.

BUT that's just based on rocker ratio alone. A few key points;

Increasing the rocker ratio will require elongating the pushrod slots with a "Lois Tool" if yur stickin with the press-in studs, and relyin on the slots rather than guideplates. If you have screw ins and/or have aluminum heads, no problem there. Also...some aluminum rockers will clear the stud bosses, but definitely not the fat bodies ones such as the Crane Energizers or off-brands like Omegas/Angus that have a lot of material around the trunion.

If I'm correct I suggest going with Comp magnum roller tip rockers or Crane/Elgine roller tips...And Elgin actually makes a 1.6 all stamped rocker I use in circle track engines that works well if the spring pressure isn't too high. But of course, even then....Elongating the pushrod slot is sometimes nescessary.....

So, I guess I should quit assuming and let you tell me exactly what you have and I'd be more than happy to walk you through it.

Felber

P.S. I guess Dave posted while I was typing, and YES Harland Sharp's are awesome, but consider the things I've mentioned in the actual fit, and IF you're goin full rollerized rocker in your application (and it fits) I'd suggest the idea of the Scorpion 1.7...Oh and by the way....That IS if you have the valvesprings to accomodate the 1.6 nevermind the 1.7...So once again...Don't be afraid to ask questions.
 
OK, heres the specs on the heads. stock, cast iron, pressed in studs, no guide plates, all stock valves and springs, casting # 462624. I am aware of the possibility of elongating the pushrod guide holes and I have looked at all of mine with the stock 1.5's and pushrods installed and It looks like I'll have to do at least 1 on each head. Glad you mentioned the roller tip only models. I had looked at those but the macho side of me said if your gonna get some go all out full roller, but if you don't think I need them I'll shop the magnum roller tip models. My cam with 1.5's is only a .368/.398 lift, and if I go to 1.6's I am still only .392/.424 at the valves. What's the diagnosis?
 
Ok....In all seriousness...I think your options are pretty limited if you don't remove the heads. I doubt yur gonna be able to clear the pushrods with the higher ratio rockers, especially if you're already close with 1.5s.

Now my suggestion.....If yur already that close/tore down to change the rockers....Rip the heads off, use the Lois tool and elongate the slots. And another benefit? Check the deck height of the pistons and you most likely will be able to put an .019 or .028 head gasket in there and increase compression, detonation resistance, and SNAP all at the price of a set of head gaskets and a lil bit of your time. Combine that with the increased lift-velocity of the new rockers and I'm bettin yur a very happy camper.

Felber
321 591 2757
 
Budget is limited, could swing the magnum roller tip rockers and some head gaskets but I can't swing gettin screw in studs and installation of them. Can you tell me the best place to get a thin head gasket set. I don't have a lois tool but I thought about mounting them on my milling machine and elongating that way, any thing I need to be aware of if I try that or should I not try that at all and just get the lois tool.
 
Well I'll avoid giving mixed tech signals. IF you start to find yourself getting that far into mods PLEASE consider cost and effect.

Dave you HAVE to agree that he should do himself a favor and not put $250+ into 76cc smog heads with all used components when you can buy MUCH better Vortecs that WILL clear for a few bucks more. GREAT advice comin here, but kinda think we can't see the forest for the trees perse'. We can uprgrade things to the point that he's gonna build a new engine.

I'm just tryin to give balanced advice based on experience. And what I read from the post was that he wanted a simple upgrade considering higher ratio rockers, and I wanted to state facts of how/what it takes to do so. JMO

Felber
 
NorthWestFloridaBoy":2pkt0frs said:
Budget is limited, could swing the magnum roller tip rockers and some head gaskets but I can't swing gettin screw in studs and installation of them. Can you tell me the best place to get a thin head gasket set. I don't have a lois tool but I thought about mounting them on my milling machine and elongating that way, any thing I need to be aware of if I try that or should I not try that at all and just get the lois tool.
Click to expand...

I'm hearin ya....Now seriously...Buy the Lois tool, or in fact I can mail it to you...I actually haven't even used it since my last one got loaned out and didn't come back. I haven't built a stock-headed SBC in over a decade, so it's all yours if need be. Now as for puttin it in your mill....I wouldn't suggest it....I know you can and most likely are better at opperatin a mill than myself LOL, but to find the center points and the setup of the machine really isn't worth your effort when you can buy the tool for $30...All it takes is a drill bit (provided actually) and the ONLY reason you have to pull the heads is to keep iron shavings out of the engine, and IF you wanna be creative there.....Save headgaskets and some labor perse'. But the thinner head gaskets would be nice...The .019s are stamped steel and are MEGA cheap...Can buy em from Mr Gasket or Fel-Pro....The .028s you can buy directly from GM...Hope this helps.

Felber
 
Thanks for the offer on the loaner tool Felber..I will take you up on that when I get the arms, and don't worry I will make sure it gets back to you. I didn't want to do the stud replacement because that meant sinking money into heads that were'nt worth having money sunk into. I planned on getting some vortec heads in the future, but for now these are what I got. I don't have a problem pulling the heads to modify the holes and I would rather do that anyway and go ahead with the thin gasket. So to recap I am going to get the comp magnum roller tip 1.6 arms, thin head gasket, borrow the lois tool from you, put it all back together and be a happy camper, does that sound right?
Thanks for letting me pick you guys brains, that's what I love about this site, I got some great insight from some real pros and now I am headed in the right direction.
 
Just lemme know when you need it and I'll hook ya up.

As for 1.6s on Vortecs...Yes cuz they have drilled holes rather than slots, but ya gotta use tip-aligning style rockers, and also thin bodies to clear the valvecover center-bolts. AKA specific to the Vortec head..Crane and a few others make em.

Felber
 
You guys know where to get a set of rollers for a buick 455? Only places I`ve found where taperformance and poston,but at 750.00 a set,was wondering if there was a better priced set available?
 
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