Discussion in 'Street/strip 400/430/455' started by matt68gs400, Jul 7, 2019.
You can get enough lift with stock
Yes, once you go past around .525" or so roller rockers become more desirable. Can you get by without them, sure, maybe.
500hp with TA aluminum stage 1 heads and stock replacement rockers. Does that work out?
From all the reading on this board i came to the assumption that the better head the less aggressive cam you need and 500hp should be doable.
I like matts post because it seems we are in the same boat..
.the point of me mentioning the bronze bushing is I'm almost 100% certain the early KB BUICK rollers were bushed to allow for repair and keep the aluminum from eating the shaft , if I'm wrong on that I'll more than happily eat crow,..
You included the TA rockers in the group of only being hard anodized riding on a steel shaft which they most certainly aren't and never have been. Or that's how I initially read it,.That's where my initial disagreement was lumping the shitty Proform rockers in with TA's.
And the above was my reference to the new bronze bushed LS trunion upgrade.
As to an aluminum body rocker riding on A steel shaft is as I said that is ignorant I dont care how good the coating is or how "genius" the engineer thinks he is.
Looks like Harland agrees with me
I was however under the impression that there was a design difference between the "needle" and "Torrington" bearing mainly in the way the bearing is captured hence the reason I spone of each independently but if they are the same animal then thatz cool too ha.
whats a "LS" ??
( I own 3 of them , so just joking)
I'm referencing current or last 20yrs of manufacture of roller rockers)
How many aluminum-head engines have the iron or steel camshaft riding directly in the parent metal of the head?
How long have they been making aluminum-based main and rod bearings to ride on a steel or iron crank?
Some small engines and air compressors have an aluminum connecting rod that has NO separate bearing, the aluminum rod is used directly on the iron or steel crankshaft.
I'm NOT saying that aluminum-bodied rocker arms are better without a bushing.
Overall, I just don't like aluminum rocker arms.
Correct me if I'm wrong.....But isn't "Roller Rocker" short for "Roller-Tip Rockers" which has nothing to to do with the mechanism between the shaft and the rocker?
BTW...I wouldn't run Proform anything.
With the rockers you obviously have spring psi pushing up and turning,..on a small percentage of the shaft dia,..its only a matter of time till the steel goes away,..that's why it's almost impossible to find a nice set of 67-71 buick rocker assemblies.
I understand what your saying but all we go on is evidence and there's plenty of it ha. With the overhead cam riding on the aluminum head,.I would Imagine the built in oil clearance and the 360 load distribution plays a role in its survival
That would certainly be a better description for the Proforms,..and even the tips feel a little notchy.
Alot of us know how fun TA rockers are to put on while leaning over the fender,..damn things spinning all over the place ha
The roller on the rocker tip that actuates the valve up and down makes it a roller rocker, NOT because they have roller bearings that ride on a shaft.
I'd argue that that is not correct.
The first "roller tip" rockers I ever heard about were made by Comp Cams, they were very careful to acknowledge that only the tip "rolled".
REAL roller rockers have a bearing at the fulcrum, in addition to the roller tip.
REAL engineers know that only the roller bearing at the fulcrum makes a difference--at least, in the diameters in use in automotive rocker arms. The "roller" at the valve tip is a waste of time, money, effort, and enthusiasm (but it looks good, so marketing makes sure that the tip roller is included.) There are certain aircraft engines that have a "real" roller at the valve tip, which is big enough to do some good. Problem is, it's too heavy for automotive RPM levels. Aircraft engines tend to be topped-out at ~3000--3500 rpm.
I'm always right, even when I'm wrong - Tony Montana
Harland Sharp 1st came out with the ROLLER TIP ROCKER, in 1960.
soon afterward came the full roller bearing rocker arm. ( fulcrum bearing, not just the tip)
the term "roller rocker" referrers to roller bearing fulcrum, NOT TIP!
the term "roller TIP rocker" means what it says,
It's interesting to read this thread. But often discussion drifts away from the OP's intentions.
I think it's safe to say that when you have near unlimited budget there is no reason NOT to go with roller rockers and roller lifters. But if I get Matt right he is tries to build a street engine that makes reasonable power and not a race engine.
As with all those components "wear" is the problem but these engines rarely see rpm's higher than 5000 and the cars get used rarely. In my case it's almost certain it will never see a dragstrip. So I cannot make myself comfy with spending almost USD 1000 on parts that are not really needed. So we look into lower priced options.
I think all the proform stuff is low quality. I will not use it. But why spend so much money on something you probably do not need.
So my conclusion is either go with stock replacement if a mild cam is used or invest in high quality stuff when you need it since the cheap stuff does have its disadvantages
I absolutely love how lots of members share their knowledge. It really help making decisions about something you probably do for the first (and probably only) time.
Exactly my reason back in the early 90's I decided on TA's FULL roller rockers over KB's roller tipped rockers, even tho TA's were about 300 bucks more than KB's
I'll throw another option out there. 68-69 rockers, better than later ones and last pretty long . I installed 69 rockers on Sandy's "X" in 1991, she runs 12.7's with a KB 118 cam and iron manifolds, HP level, I don't know but very reliable and she has over 4000 street mikes on it, drove it to BG, Indy, and GSX reunion in Columbus, beat the snot out of it on the track then drove it home. Hasn't been apart since '91.
You are spot on. Initially I thought for just a little more that proform might be a good budget but. But I won’t put garbage in to save money. I’m just better off with the TA $200 stamped steel for a car with less than 0.500” lift and goes to the track 2-3 times a year.
I still appreciate all the opinions though. It’s very helpful and I learn a lot.
I’m curious what makes them better? Also, can these be purchased afternarket? Are they direct bolt on to a 71 head?
Also, does anyone make a 1.6 ratio stamped steel rocker to fit on the factory rocker shaft?
I concur with this. The one advantage of roller tip rockers, at least in most cases, is the accuracy of the ratio. If stock were swapped to roller tip and an engine picked up 5 numbers I'd put my money on it being related to consistent ratios across the board.