Hot Rod Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
499 Posts
Discussion Starter · #1 ·
Does anyone make a pushrod length check tool that is very sturdy and will not bend when used with typical stock/mild performance springs? Like say open pressures of 200 to 350lbs?
 

·
Registered
Joined
·
499 Posts
Discussion Starter · #3 ·
Seriously? Well I'm mean that's what I was hoping but I was under the impression from the reviews and all the info I've gathered that the common length checkers from comp, lunatic etc couldn't be used on a fully assembled engine and needed a super light spring installed or they'd bend
 

·
Race it, Don't rice it!
Joined
·
8,828 Posts
Your either uninformed, misinformed or chloroformed to believe that. Even the really cheap 5/16x.060 wall stockers are fine at 350 over the nose for the purposes of checking lenght. Any of the standard checkers will be just fine for you.
I would stick to the manufactures you plan to buy from for accuracy of the measurement.
 

·
Registered
Joined
·
499 Posts
Discussion Starter · #5 ·
Usually internet info is all over the place, but all the magazine articles, and even comp cams says DO NOT USE adjustable pushrod length checkers without installing lightweight check springs.

The tool isn't too expensive, I guess I'll just order one and see for myself.
 

·
Race it, Don't rice it!
Joined
·
8,828 Posts
Well, Comp is good about dumbing it down to protect you from yourself because they assume your stupid and don't know any better. I personally don't even own a checking spring. If anything, I take the inner spring out sometimes. It'll be fine. Trust me. Most of us here are tryting to get guys to do the mid lift way of checking for PR lenghts so you don't need to remove anything or even rotate the crank.
 

·
Registered
Joined
·
499 Posts
Discussion Starter · #8 ·
I ordered a crane version with the locknut's, and the comp high-tech version too with no nuts on it.

My Cleveland has hydraulic flat tappet lifters, so I purchased a couple cheap summit hyd flat lifters that I could weld or epoxy fill to prevent plunger movement during testing.

Hopefully even if the spring pressure is too much for these adjustable push rods, the guide plates will help keep them from bending.

Will report back with results!
 

·
Registered
Joined
·
499 Posts
Discussion Starter · #9 ·
I ordered the comp cams one.. thenz found out that Smith Bros. makes adjustable pushrods that you can use in a running engine! I just ordered a few different sizes
 

·
Registered
Joined
·
609 Posts
Here's a link to the "mid-lift" technique that Mr. Johnson mentioned:

He does have the light "checking" springs on, but notice that he only compresses the springs when he's demonstrating something, not when he's doing the actual measurements.
 

·
Registered
Joined
·
1,556 Posts
Here's a link to the "mid-lift" technique that Mr. Johnson mentioned:

He does have the light "checking" springs on, but notice that he only compresses the springs when he's demonstrating something, not when he's doing the actual measurements.
Only thing is OP is working with an unknown cam.
Adam, my suggestion is. You're this far in the game, just let the boys know your combo, and ask for a cam recommendation. That way you know you will be rocking when you get this thing all together! Might cost a few more bucks, but it will be worth it.
 

·
Registered
Joined
·
609 Posts
Well if he's working with an unknown cam, then the first thing would be to degree the cam...
Figure out what the cam is before you bother buying pushrods.
Or get another cam based on what you should have, like EA said...
 

·
True Hotrodder
Joined
·
1,955 Posts
I ordered a crane version with the locknut's, and the comp high-tech version too with no nuts on it.

My Cleveland has hydraulic flat tappet lifters, so I purchased a couple cheap summit hyd flat lifters that I could weld or epoxy fill to prevent plunger movement during testing.

Hopefully even if the spring pressure is too much for these adjustable push rods, the guide plates will help keep them from bending.

Will report back with results!
I guess the modified lifters will work okay, in the past I have just used a solid flat tappet to do the checking.
 

·
Registered
Joined
·
499 Posts
Discussion Starter · #14 ·
The engine was running great before disassembly, and I don't want to change anything yet.

I was only going to put new head gaskets on this engine, but when I got it apart, it was apparent that the heads were getting very worn and the bottom end needed new bearings.

so after the machine shop completely remanufactured the heads and installed hardened exhaust seats, and I out the heads back on, I noticed the rockers were not sitting right anymore.

I've cut and reworked and weld the pushrod guide plates, now I need to set proper geometry and get new pushrods

There's not enough money to invest in new cam right now, plus the carb is already tuned to this cam. I've ordered a dial indicator and will check the cam lift through lifter bore.
 

·
More for Less Racer
Joined
·
20,952 Posts
So is it good enough in a "mystery cam" situation to just get the lobe lift, and multiply by your rocker ratio?
Or is it best to measure the actual valve lift?
You can get the lobe lift of the cam lobe with a dial indicator on the lifter and use that with no problem....actual valve lift is just figured by multiplying lobe lift x rocker arm ratio....that's the same numbers that would be on the cam card, both lobe lift and theoretical valve lift at the correct rocker ratio.
 

·
Registered
Joined
·
609 Posts
You can get the obe lift of the cam lobe with a dial indicator on the lifter and use that with no problem....actual valve lift is just figured by multiplying lobe lift x rocker arm ratio....that's the same numbers that would be on the cam card, both lobe lift and theoretical valve lift at the correct rocker ratio.
That's what I figured, I just thought it was a question worth asking...
 
1 - 19 of 19 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top