Rockers,Steel Or Alloy??????

General Chat About Exhaust, Cylinder Heads, Fuel Systems And Intake

Moderator: phpBB2 - Administrators

Post Reply
User avatar
john 215
Getting There
Getting There
Posts: 216
Joined: Sun Dec 03, 2006 6:01 pm
Location: luton

Rockers,Steel Or Alloy??????

Post by john 215 »

I am part way building a 4.6,just wondered what opinon you Ladies and Gents have on standard alloy rockers or steel :? ? In my case going to be running a Viper Typhoon camshaft with Real Steel stage 3 heads fitted with there DW 550 valve springs.Going into my TR7 with the odd RWYB in mind.What experience has anyone had with steel rockers? Can these be used with standard or large pushrods as my heads have been modified for larger diameter push rods.Would like roller rocker but a bit too pricey :(


LIVE LIFE A QUARTER OF A MILE AT A TIME.
ian.stewart
Forum Contributor
Forum Contributor
Posts: 2419
Joined: Sat Nov 18, 2006 1:59 pm
Location: Far Far south, any further south and my feet are wet

Post by ian.stewart »

I am running standard rockers, double valve springs and a silly european touring car mechanical cam, and rev the engine to 7k, had no problems at all.
Ian :D :D
THE SMOKING GNU
12.604 with an old boiler of a RV8 and no gas
WHY are there so many IANS on this site???????
User avatar
john 215
Getting There
Getting There
Posts: 216
Joined: Sun Dec 03, 2006 6:01 pm
Location: luton

Post by john 215 »

Thanks for reply Ian,a friend circuit races a TR8,and does the same just thought would ask opinons before parting with the 'Hard Earned'
Once again cheers and Happy New Year, John.
LIVE LIFE A QUARTER OF A MILE AT A TIME.
katanaman
Site Admin
Site Admin
Posts: 3081
Joined: Fri Nov 17, 2006 7:29 pm
Location: Edinburgh
Contact:

Post by katanaman »

alloy is lighter so should be better on a high revving engine, less mass so it can be controlled better. That said Rover used steel rockers on their competition engines. At the end of the day steel rockers were cheaper so that's what I got.
User avatar
ihatesissycars
Forum Contributor
Forum Contributor
Posts: 938
Joined: Sat Nov 18, 2006 8:22 am
Location: Aaaaaaampshire!

Post by ihatesissycars »

I have steel but i would've thought ally would be better for higher revs as they're alot light than my steel ones.
V8'less but a fountain of dorky knowledge ref v8's!
User avatar
john 215
Getting There
Getting There
Posts: 216
Joined: Sun Dec 03, 2006 6:01 pm
Location: luton

Post by john 215 »

Hi Marki,had'nt thought of the weight thing,was wondering about the steel on steel action are they bushed or just plain?
Happy New Year To You.
LIVE LIFE A QUARTER OF A MILE AT A TIME.
ian.stewart
Forum Contributor
Forum Contributor
Posts: 2419
Joined: Sat Nov 18, 2006 1:59 pm
Location: Far Far south, any further south and my feet are wet

Post by ian.stewart »

katanaman wrote:alloy is lighter so should be better on a high revving engine, less mass so it can be controlled better. That said Rover used steel rockers on their competition engines. At the end of the day steel rockers were cheaper so that's what I got.
Rover used Volvo rocker arms, certainly cheaper to buy than tooling up for a production run, and if my memory serves me right the works cars were docked points in the ETCC for running non homologated parts, evedently a scruteneer looked down the oil filler hole as saw the word VOLVO on top of the rocker arm, WHOOPS
THE SMOKING GNU
12.604 with an old boiler of a RV8 and no gas
WHY are there so many IANS on this site???????
katanaman
Site Admin
Site Admin
Posts: 3081
Joined: Fri Nov 17, 2006 7:29 pm
Location: Edinburgh
Contact:

Post by katanaman »

Your right Ian but my point was that steel is fine from an engines point of view.

John they are cast so have less friction steel to steel as cast has a self lubricating property than alloy to steel has. The alloy rockers also have a nasty habit of picking up fine particles from the oil which embeds in the soft alloy and grinds away at the shafts. That's why usually the rockers measure up fine but the shafts have worn. Its also another reason why you shouldn't use old alloy rockers on new shafts as the shafts will just get torn up again.

I wouldn't worry about it and just use what you fancy or can afford, your engine isn't going to be revving to huge figures with that cam anyway so the extra weight wont mean a lot. Just as an aside I have never seen a failed alloy rocker so they are plenty strong enough.
ian.stewart
Forum Contributor
Forum Contributor
Posts: 2419
Joined: Sat Nov 18, 2006 1:59 pm
Location: Far Far south, any further south and my feet are wet

Post by ian.stewart »

katanaman wrote:Your right Ian but my point was that steel is fine from an engines point of view.

John they are cast so have less friction steel to steel as cast has a self lubricating property than alloy to steel has. The alloy rockers also have a nasty habit of picking up fine particles from the oil which embeds in the soft alloy and grinds away at the shafts. That's why usually the rockers measure up fine but the shafts have worn. Its also another reason why you shouldn't use old alloy rockers on new shafts as the shafts will just get torn up again.

I wouldn't worry about it and just use what you fancy or can afford, your engine isn't going to be revving to huge figures with that cam anyway so the extra weight wont mean a lot. Just as an aside I have never seen a failed alloy rocker so they are plenty strong enough.
I quite agree, Cast steel rockers are fine in most applications, I think Edelbrock now make investmant cast stainless steel, quite light too, Stock Ford X flow rocker arms will go way beyond 9k with a little bit of fettling [deburring bassically] while we are talking rocker arms, why are most roller rockers so heavy, they may gain a bit in lost friction, but what about all the power lost accellerating all that mass. do they counteract themselves :D :D
THE SMOKING GNU
12.604 with an old boiler of a RV8 and no gas
WHY are there so many IANS on this site???????
User avatar
HairbearTE
Guru
Guru
Posts: 870
Joined: Sat Nov 18, 2006 12:27 am
Location: Melton Mowbray

Post by HairbearTE »

Ian i think it more a case of the standard rv8 rocker gear being so light. Dont forget many roller set-ups for the rv8 have been put together using pieces that may have originally been intended for chevy applications. In comparison to the weighty stamped steel arms of a stock chevy engine they are in fact lightweight. Also it is worth noting that while some nice aftermarket set-ups can appear to look bulky the most important issue is weight at distance from rockershaft centerline (for obvious reasons). I expect that when that is taken into account there is probably not a lot in it between a big ally rocker arm and a stock steel one.
Image
Boosted LS1
Knows His Stuff
Knows His Stuff
Posts: 518
Joined: Thu Nov 23, 2006 12:05 am
Location: Nottingham, Notts, England, UK
Contact:

Post by Boosted LS1 »

That was the point I was about to make:) weight around the shaft isn't really the issue. It's weight at the nose which is important.

The volvo rockers were also adjustable iirc.

Boosted.
Image
Post Reply

Return to “Exhaust, Cylinder Heads, Fuel And Intake Area”