Custom Length Pushrods for Olds Gen 1 - 324

Thread Tools
 
Search this Thread
 
Old Apr 3, 2024 | 01:25 PM
  #1  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Custom Length Pushrods for Olds Gen 1 - 324

Working on a 1955 block with 1956 #10 heads. My block is decked slightly ~.010, but my heads will need be cut at least .020. I am NOT building a race motor, just a stock rebuild with performance upgrades like a different cam when/where appropriate with cost.
Question: Should I attempt to find custom length pushrods or adjustable rockers? I have the rocker shafts and rockers already cleaned and ready to go, so I am concerned with cost. I DO NOT have pushrods yet. Thanks in advance for any advise.




Last edited by madmax442.com; Apr 3, 2024 at 01:31 PM.
Old Apr 3, 2024 | 05:02 PM
  #2  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,981
From: Beautiful Southern Maryland
If you are using a non stock camshaft then you will probably have to do something. If your rockers are in good condition I would lean towards custom pushrods. They really are not that terribly expensive. You might even be able to find something in a stock dimension. Most performance pushrods are available in .050" length increments for about $130 for a complete set. I'm sure that is less than what a set of adjustable rockers will be.
Old Apr 4, 2024 | 06:30 AM
  #3  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
thank you, can you recommend a source or two?
Old Apr 4, 2024 | 06:35 AM
  #4  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,981
From: Beautiful Southern Maryland
If you end up needing a custom length I have been using Manton. Any of the cam companies will have pushrods in .050" increments. Comp Cams, Erson etc. But you need to get everything done and put together first and then check and measure.
Old Apr 4, 2024 | 09:12 AM
  #5  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Yes, I will use a pushrod measuring tool with a light test spring once I have the heads on. Do you recommend using the 4 outer pushrods with holes, or just stick with the standard no hole Olds 324 pushrods for all 16?
Old Apr 4, 2024 | 09:14 AM
  #6  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,981
From: Beautiful Southern Maryland
Originally Posted by madmax442.com
Do you recommend using the 4 outer push rods with holes, or just stick with the standard no hole Olds 324 pushrods for all 16?
I am not familiar enough with that engine to answer that question. Hopefully somebody else here will
Old Apr 4, 2024 | 09:42 AM
  #7  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Originally Posted by BillK
I am not familiar enough with that engine to answer that question. Hopefully somebody else here will
Oh, I thought you had built a 324 based upon your responses. Thanks.
Old Apr 4, 2024 | 10:03 AM
  #8  
jmcghee's Avatar
Registered User
 
Joined: Sep 2017
Posts: 602
From: New Castle De
Listen to BillK

Originally Posted by madmax442.com
Oh, I thought you had built a 324 based upon your responses. Thanks.
Bill may not have built a 324, but he has built, probably thousand of engines. When you start decking and milling , ANY engine, you need to measure pushrod lenght. There are members here that have built 324s . they will be along soon and answer your question about the pushrod oil holes . Wishing you sucess in your build.
Old Apr 4, 2024 | 11:35 AM
  #9  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Originally Posted by jmcghee
Bill may not have built a 324, but he has built, probably thousand of engines. When you start decking and milling , ANY engine, you need to measure pushrod lenght. There are members here that have built 324s . they will be along soon and answer your question about the pushrod oil holes . Wishing you sucess in your build.
Yes, I understand I need to measure, I get that. I have also built many engines, just not a 324, there are some issues with finding parts, non-adjustable valve train, the oiling system, etc. I was just curious on what folks are doing is all. I read many folks use the outer 4 pushrods for extra oiling, but not do all 16 as that would starve the bearings. All the oiling for a Gen 1 top end comes from the rocker shaft.
Yes, hopefully someone with chime in. If not, I will just call Tony. Thanks.
Old Apr 4, 2024 | 12:11 PM
  #10  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,981
From: Beautiful Southern Maryland
Originally Posted by madmax442.com
I read many folks use the outer 4 pushrods for extra oiling, but not do all 16 as that would starve the bearings.
I was just looking at the oiling system and I am not sure if that would really help anything at all.

First of all are the lifters designed to meter oil up into the push rods ? Or do you use the later model lifters ? I don't know if they will even fit ?

And then all I can see it doing is maybe filling up the rocker shaft a little faster at startup ? Once the shaft is filled it really wont do much good that I can see. I don't buy the starving the bearings thing. You can only pump so much oil through the clearances in the rocker assembly. It does not matter if it comes from the block or the push rods you can still only pump so much oil through.

Ill be interested to see what you find out. I am always up for learning something new
Old Apr 4, 2024 | 11:01 PM
  #11  
Charlie Jones's Avatar
Phantom Phixer
 
Joined: Dec 2011
Posts: 5,534
From: Apopka, FL
Originally Posted by madmax442.com
Yes, I will use a pushrod measuring tool with a light test spring once I have the heads on. Do you recommend using the 4 outer pushrods with holes, or just stick with the standard no hole Olds 324 pushrods for all 16?
The first gen Olds didn't oil the rockers thru the push rods.
The rocker shafts were supplied with metered oil that was delivered by passageways in the block and heads.
None of the pushrods should have holes, They don't deliver oil.

Once you get the heads on, try assembling the rocker assembly with the original push rods.
Turn the engine so that the # 1 cylinder is in the firing position.
Grab the pushrods between your thumb and forefinger and try to move it up and down.
If you cannot move it up and down. Then it may be long enough.
If you can twirl it between your finger and your thumb it may be OK.
Turn the crank 1/8 of a turn and try the next cylinder in the firing order.
Old Apr 5, 2024 | 07:35 AM
  #12  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Originally Posted by Charlie Jones
The first gen Olds didn't oil the rockers thru the push rods.
The rocker shafts were supplied with metered oil that was delivered by passageways in the block and heads.
None of the pushrods should have holes, They don't deliver oil.

Once you get the heads on, try assembling the rocker assembly with the original push rods.
Turn the engine so that the # 1 cylinder is in the firing position.
Grab the pushrods between your thumb and forefinger and try to move it up and down.
If you cannot move it up and down. Then it may be long enough.
If you can twirl it between your finger and your thumb it may be OK.
Turn the crank 1/8 of a turn and try the next cylinder in the firing order.
Yes, aware the rocker shaft supplies oil not the pushrods, just read somewhere folks use the outer 4 for extra oiling. So for the purposes of this discussion, I am sorry I brought it up. I am simply wondering where to get custom length pushrods for a 324. They will certainly be too long once I mill the crap out of my heads I picked up as the deck surface is pretty pitted (earlier post). The block will need to be desked as well. Unless I can find some thicker head gasket (don't want to), then the pushrods will be probably .040 to .050 too long. What do folks do? Live with the extra preload or where do you find the pushrods?
Old Apr 5, 2024 | 08:35 AM
  #13  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,981
From: Beautiful Southern Maryland
Originally Posted by madmax442.com
where do you find the pushrods?
I already gave you two sources ? Manton will make whatever you want https://mantonpushrods.com/ So will Smith Brothers https://www.pushrods.net/
Old Apr 5, 2024 | 08:36 AM
  #14  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Originally Posted by BillK
I already gave you two sources ? Manton will make whatever you want https://mantonpushrods.com/ So will Smith Brothers https://www.pushrods.net/
Great thanks.
Old Apr 5, 2024 | 10:10 AM
  #15  
Charlie Jones's Avatar
Phantom Phixer
 
Joined: Dec 2011
Posts: 5,534
From: Apopka, FL
Originally Posted by madmax442.com
Yes, aware the rocker shaft supplies oil not the pushrods, just read somewhere folks use the outer 4 for extra oiling. So for the purposes of this discussion, I am sorry I brought it up. I am simply wondering where to get custom length pushrods for a 324. They will certainly be too long once I mill the crap out of my heads I picked up as the deck surface is pretty pitted (earlier post). The block will need to be desked as well. Unless I can find some thicker head gasket (don't want to), then the pushrods will be probably .040 to .050 too long. What do folks do? Live with the extra preload or where do you find the pushrods?
My point was that you may not need custom push rods.
The lifters have a .050 range of motion.
Old Apr 5, 2024 | 10:18 AM
  #16  
madmax442.com's Avatar
Thread Starter
madmax442.com
 
Joined: Feb 2014
Posts: 486
From: Albuquerque, NM
Originally Posted by Charlie Jones
My point was that you may not need custom push rods.
The lifters have a .050 range of motion.
Ok, great point! So, that the preload spec, very helpful!
Old Apr 5, 2024 | 01:02 PM
  #17  
Charlie Jones's Avatar
Phantom Phixer
 
Joined: Dec 2011
Posts: 5,534
From: Apopka, FL
Originally Posted by madmax442.com
Ok, great point! So, that the preload spec, very helpful!
Double check that preload spec on the lifters you are using.
Most are 40 to 50 thousands that's why I threw that figure out there.
Rocker arm and shaft wear actually work in your favor.
You may be OK with stock pushrods.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Nickyloves442s
Racing and High Performance
17
Feb 15, 2019 09:16 AM
Mattyp77
Big Blocks
10
Sep 7, 2018 04:32 AM
2oldsguy
Parts For Sale
1
Jun 2, 2018 06:28 PM
Erinyes
Big Blocks
6
Aug 15, 2014 08:26 AM
Oldwolf
Small Blocks
21
Nov 17, 2009 07:48 AM




All times are GMT -7. The time now is 08:44 AM.