FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: happystang on December 16, 2018, 12:34:36 PM
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Hi everyone,
I'm coming to the stage where I'm measuring for pushrod length-
Where would one order pushrods from? I'm using Harlan Sharp roller rocker arms, so I believe I'd need a 3/8" cup one one end and 3/8" ball on the other, but what diameter for the rest of the pushrods? 3/8" or 5/16"? I'm assuming I'd go with a solid pushrod? (Stock Edelbrock heads, roller cam)
I doubt there's an off the shelf size that would fit so I'd have to go custom.
Thanks!
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No to solid pushrod. Smith Brothers, Trend, Crane, Comp Cams, Trick Flow, even Pioneer, sell pushrods that will work with your parts. I prefer the Smith Brothers chromoly in either 5/16 or 3/8" depending on spring pressures and lengths needed for street use. Through the pushrod oiling, or not is available. Joe-JDC
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I'm going to be doing the same thing real soon.
I was thinking of going with hollow to reduce weight since the rollers are heavy anyway. seems logical but is that right ?
+ 1 on Smith Brothers. they're great to work with.
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99.99999999% of your pushrods are made of tubing.
The tubing is cut and ends are pressed in. Those ends will vary according to what you need to do. Some of the ends will be solid cups, some will be tool steel, some will be 3/8" ball, etc, etc.
The only thing you need to decide on is what diameter tubing you want, whether or not you want them to oil, and what ends you need.
Buy as big of diameter as you can fit in the pushrod tubes in the intake manifold. If you're oiling through the lifters, then you want a pushrod that you can see through. If you're oiling through the head, then you can opt to buy pushrods with a tip welded up. If you're running a factory non-adjustable rocker, then you need a 3/8" ball on one end and a 5/16" ball on the other. If you're running a factory adjustable rocker, then you need a 3/8" cup on one end and a 5/16" ball on the other. If you're running some of the new aftermarket stuff, then they use a common 5/16" ball on both ends.
My advice is to buy a good pushrod length checking tool, get the measurements you need, then call Trend, Smith Brothers, Manton, or contact one of the engine builders here who have accounts with the ones I listed.
The weight of the pushrod really has no bearing on anything. It's seems counterintuitive, but it's kinda like sprung/unsprung weight when we talk about a chassis. The jist of it is buy as big as you can fit.
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Not trying to hijack the original poster here, but maybe we have the same questions.
my pushrods I took out were solid with a 5/16 ball on both ends. so obviously I was not oiling through the rod. is there any advantage to having oil flow through the push rod ?
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Not trying to hijack the original poster here, but maybe we have the same questions.
my pushrods I took out were solid with a 5/16 ball on both ends. so obviously I was not oiling through the rod. is there any advantage to having oil flow through the push rod ?
On some setups, it's cheaper, because the pushrod is readily available from a SBF/SBC/BBC/BBF, etc. However, the rocker arm has to be able to oil that way. Not all rockers will pass oil from the pushrod tip and oil the fulcrum, rocker tip, etc.
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So with the roller lifters and stock rockers I should go with a hollow 3/8 push rod with no oil hole of whatever thickness they suggest I take it ?
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Adjustable rockers?
If so, 3/8" .080" wall thickness, 3/8" cup on one end, 5/16" ball on the other end, non-oiling.
Non-adjustable rockers?
If so, 3/8" .080" wall thickness, 3/8" ball on one end, 5/16" ball on the other end, non-oiling.
Typical pushrods are just tubing, not solid. The ends are either solid or drilled depending on whether the pushrod needs to pass oil from the lifters or not.
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got it.
So on a stock non adjustable rocker set up if I take my push rod length checker and set it at zero lash on the base circle how much preload should a hydraulic roller lifter have ? I'm sure if I run it over to Smith Bros they can make a set if I know the proper preload.
Stock rockers are 1.5 ratio correct ?
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Stock non-adjustable rockers are 1.73:1.
I run them at zero lash plus .060" preload on standard travel lifters.
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.060 seems like quite a bit but I like it. I don't imagine a roller lifter wants any slack if you want them to last.
So just to make sure I'm clear on this , I find zero lash then have them made .060 longer ?
And one last dumb question, does the 3/8 ball go on the lifter or the rocker ? because both ends on my push rods were 5/16.
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I'm running Isky 3/8 cup and ball pushrods with Dove roller rockers. I noted that most hydraulic lifters offer no provision for oiling via the pushrod They're high quality and about half the price of Crane. The Lunatti pushrods are 11/32. They offer one length at 245.00 a set. Smith Bros are great quality and available in custom lengths.
-Keith
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.060 seems like quite a bit but I like it. I don't imagine a roller lifter wants any slack if you want them to last.
So just to make sure I'm clear on this , I find zero lash then have them made .060 longer ?
And one last dumb question, does the 3/8 ball go on the lifter or the rocker ? because both ends on my push rods were 5/16.
Zero lash, add .060” for preload.
On a factory non adjustable, the 3/8” ball goes in the rocker.
I don’t know of any hydraulic roller lifter that won’t allow pushrod oiling but some rockers won’t allow it.
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got it. will do.
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I didn't see anything about a roller cam, just rockers...... I haven't seen any FE hydraulic lifters that provide oiling via the pushrod. Perhaps there are, just not common.
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I didn't see anything about a roller cam, just rockers...... I haven't seen any FE hydraulic lifters that provide oiling via the pushrod. Perhaps there are, just not common.
It's pretty rare that I've seen FE specific hyd flat tappet's unless special ordered these days. Most places (engine rebuild supply places like EngineTech and regular parts stores like Napa) all show only 1 or 2 part numbers that cross to nearly all Ford V8's so you end up with pushrod oiling at the lifters. Not saying its the way to go, but it's the economy of scale and the way these companies help the profit margin. The last time I did a flat tappet 390 I had to special order the "correct" hyd lifters for it because I couldn't get them anyplace local.
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Okay, I'm headed over to Smith brother tomorrow so I want to make sure this is right.
It's okay to put the piston on TDC compression stroke and measure the push length on that cylinder correct ?
So in doing this as you'd expect I have some rod lengths that are a tiny bit shorter than others, so I assume I'd use the shortest one as my length for the set ? And I'm not doubting you Brent, but the instructions say .030 preload and we're talking .060 preload. so to be sure .060 is what I want right?
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i just thought of a possible problem in checking for correct pushrod length.you said you have hs adjustable rockers.they recommend 0-2 threads on the rocker adjust bolt sticking out of the bottom side of the rocker arms.make sure the adjust bolts are not screwed down too far or not far enough when checking for proper pushrod length.i ran into this issue when i bought a set of hs rockers.
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I think that was the OP. I just have stock rockers.
In doing some reading .060 is actually isn't even on the high side . Hughes calls for .080 actually. I'm not sure where comp came up with .030 but it says that's for all hydraulic lifters.
looks like .060 it is.
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.060" on the preload.
For measuring, you want to make sure that the adjusters are choked up tight to the rocker arm body, as fryedaddy says. You want them down far enough that it gives you pushrod cup to rocker arm body clearance, but you don't want them down so far that it starts giving you "pushrod sweep". If the adjusters are hanging way down, a lot of cam lobe lift is translated into pushrod end movement instead of valve movement.
As for where to measure, I think the "EVO" method is more accurate than the TDC method. Pick out a cylinder, roll the engine over until the exhaust valve starts to open, then measure the length on the intake valve. When you're done, roll over until the intake valve opens and starts to close, then measure the one on the exhaust valve.
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OK, I'll check it again and head over to Smith Bros in Redmond.