• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Pushrod length vs lifter brand

Cranky

Banned Henchman #27
Staff member
FBBO Gold Member
Local time
2:27 PM
Joined
Dec 4, 2009
Messages
34,017
Reaction score
41,693
Location
Pasadena, Texas
Engine in question is based on a 400 block.

Question #1.....do hydraulic lifters for a mild cam such as something around .480 to .500 lift vary a bunch between brands as far as plunger dept/height goes?

Question #2....Is a ball/cup push rod that's 8.700 overall length sound about right with a Eddy 6092 head if the block deck is stock and using the old Isky 1604 adjustable rockers?

Reason I ask is there's someone that wants to buy them but hasn't done a mock up yet so I can't tell him if they'll work or not.....and I'm not too sure I want to sell them anyways.
 
My experience is lifters are pretty consistent, there are probably exceptions but I haven't seen them...

When I get to my shop I can get the info on my pushrods, they are custom length for isky rockers, 915 heads that have been cut .060, shim style gaskets & a hydraulic cam...

There was a time I'd remember the length but not anymore...LOL..


I think Edelbrock claims their heads are the same as iron heads & all parts interchange, whether that extends to pushrods?????
 
Considering most lifters are made to fit in an OEM motor without adjustable rockers I would think they're all going to be really close.
 
My experience is lifters are pretty consistent, there are probably exceptions but I haven't seen them...

When I get to my shop I can get the info on my pushrods, they are custom length for isky rockers, 915 heads that have been cut .060, shim style gaskets & a hydraulic cam...

There was a time I'd remember the length but not anymore...LOL..


I think Edelbrock claims their heads are the same as iron heads & all parts interchange, whether that extends to pushrods?????
Tried to find some info on these heads since I don't have them anymore but thought that they were a bit taller to allow for the better taller ports in them? Seems like I have read that some time back and the rocker shaft centerline was a bit higher to allow for that....
 
I found with the solid lifter cup/ball pushrods, a bit of variance between brands of pushrods, when I was replacing just a couple pushrods. I'm sure the lifters were the same. Not sure how that compares with hydraulics.
 
I found with the solid lifter cup/ball pushrods, a bit of variance between brands of pushrods, when I was replacing just a couple pushrods. I'm sure the lifters were the same. Not sure how that compares with hydraulics.

Solids are about 5/16" shorter than hydraulics... So they require longer pushrods...

BTW I looked where I thought the info on my pushrods was.... It wasn't....
 
I'm thinking now days, with any combination, you have to measure for pushrods. Even with stock applications it's best to double check. I had three different lenth pushrods (used) when doing my last build and none of them came close. Bought a checker to figure out the correct lenth and geometry so I could order a set.

Anyone wanting to buy a set has to know what length they will need first. Other than that you're just guessing.
 
Solids are about 5/16" shorter than hydraulics... So they require longer pushrods...

BTW I looked where I thought the info on my pushrods was.... It wasn't....

Right, I realize solid push rods are different length, I was just pointing out my experience was solids not hydraulic, and that the cup design difference between brands seems to vary the "effective length" a bit. I should have been more clear.
 
FWIW.

I have a 383 with Isky rockers. I purchased Crane ball/cup pushrods for the application. I didn't measure anything. I purchased their standard pushrod length out of their catelog for the application. I've installed 5 different cam with three different lifter suppliers. The pushrods fit perfect in all cases, and all the same. I run zero preload and the cup clears the rocker body by maybe 0.010".

So, my observation, as someone else suggested, they are all probably using the same or nearly the same dimension.
 
I think Edelbrock claims their heads are the same as iron heads & all parts interchange, whether that extends to pushrods?????

I have a customer who was running a 440 with a MP 509 cam and the stock valvetrain on factory heads.
He replaced the heads with RPM’s and reused all his old parts.
 
With Hyd. Lifters, the plunger depth changes a little bit. The depth difference may or may not be a problem for you or someone else.

Also, the amount of the lifters plunger has an amount that it can be depressed normally speced by the manufacturer of how far it can be depressed. Also normally the lifter has a spec of a minimum of .020 depressed from its most raised at rest position sitting against the retaining ring.

IF your using an adjustable rocker, you must take into account of where the adjuster will sit. Lastly, the head gasket thickness will come into play. With all of these super small measurements, if care isn’t taken, length of the pushrod may become a serious issue.

The way I measured is with the lifter on the base circle, the rocker arm tip on the valve tip, the adjusting screw set to 1 turn out, I use an adjustable measuring pushrod to set the length without depressing the lifter. Take it out and measure and then add in the amount of lifter depression to the adjustable measuring tool and retest rotating the engine. With a solid tappet, add the lash in at the rocker tip and set it up as before with zero play between the pushrod, lifter and rocker.

Pushrod measuring tools from most places can be purchased ez enough and this should be suggested to the potential buyer.

I wouldn’t sell him the pushrods. It can become an avenue of complaint and harassment. I’d sell him the pushrods after he did what I do above and can verify there length as the same or within a workable size he is OK with.
 
Been talking with this guy for months and months about it. He bought the Eddy heads probably 2 years ago and is wanting some more parts and push rods is one of them. Told him a good while back he needed to do a mock up......
 
Isky are the best but get that ball out too far and you can brak anything
need new adjusters?
go cup adjusters
you can even offset them for more ratio
 
Auto Transport Service
Back
Top