FrontEngineDragsters.Org Forum
Technical => Matt Shaff's Engine Shop => Topic started by: Mister_Fitz on November 16, 2016, 01:25:48 PM
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I have a set of old Brownfield heads on my 350" SBC in my FED. The intake rockers are slightly rotated due to moved/bigger valves and rocker studs on standard location. I do not like this and has started to look for some shaft mount rockers to once and for all fix this. I need 1.5 ratio and around 0.250" offset on the intake rockers to clear the intake runner. The cam lift is 0.735" in and 0.685" out, spring pressure is about 620 lbs. Max engine speed around 8500 rpm.
When I look at the high quality brands, Jesel, Comp cams, Scorpions they are about $1000 - $1300.
I don't have the hottest cam and springs around, could I get away with something less expensive? Are there any other manufacturer of shaft rocker for SBC with a more affordable price?
BR
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Don't mean to jump in on Matts tuff at all
but..I use lots of that stuff--The old Brownfields may not have correct offset from Scorpion --Jesel is the way to go--skip the others--Jesel will send correct stuff first time--If it was me I would use a set of dart adjustable guide plates --line it all up best I could--slap a set of scorpions for $250 on it and let her rip--scorpion makes a light weight set of rockers that help with the big RPM you are running--for sure have titanium retainers and don't let the "floppy rocker blues " bother you--I would invest in the jesels if they are Great heads--if just mediums or so I would wait until I got some Killer heads then invest in the shaft stuff
Shaft rockers are the best way to go by far but...there are so many heads with many different valve spacing deals--Jesel is about the only outfit I trust--they ship fast as well
Scorpion makes a killer set of shaft rockers for decent price but I bet they have pretty limited application range --it sux to get the wrong spaced parts and have to send it all back
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Don't forget T&D...
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T & D is my first choice for shaft rockers.
Dave is right about adjustable guide plates. Its a lower cost way to make most things fit right.
When we use them you have to be careful of the slot for the stud.
If your intake stud holes expose the intake port you will have a vacuum leak.
We mock it up on the heads, mark the exposed guide plate area and weld the slot up.
Sounds like a lot of work if you have never done it but its not really bad.
Clamp the guide plate to a piece of aluminum and use everdur tig rod.
Grind it flat and your ready to go.
Matt
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Something to think about. I would not invest in a set of shaft rockers for a old set of heads that could very soon be replaced with newer style heads that may need different rockers
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That is the exact point I was making
And --T&D quality is just fine but I have found over the years that Jesel ships product fast no BS'ing around--as a builder I can't stand to wait on slow delivery--T&D has left us waiting especially when you need a single replacement etc
wait until you get a set of dream heads then go shaft and never look back
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You might be right. Shaft mount rockers are a to big investment in these heads.
I have been running 3/8" rocker arm studs with a girdle for some years with out any problems. Spring pressure is around 550 lbs and lift is around .710"
Will this still work with .150" stud mounted offset rockers?
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why wouldn't work if it's just the rocker that's offset i have also run girdles with both 3/8" and 7/16" with little or no problem on a sbc also ran TD and didn't have trouble getting parts and Jesel on bbc it was just a question of getting the right parts as aftermarket heads specs vary even with the same brand