[Mertz]

What is the proper push rod length for a 72 350 that I plan on using comp cams roller tip rockers #1412?

[xntrik]

Originally Posted by Mertz

What is the proper push rod length for a 72 350 that I plan on using comp cams roller tip rockers #1412?

There are several variable factors.

valve length
lifter type
brand of heads
machine work done to heads
machine work done to block

The geometry must be checked on each individual situation.

[steve t]

i would think stock should work, but dont hold me to it

[Sean's]

Yeah , Ok 2 basic types of aftermarket Push rod,s ! Chromoly <<< Touted as being the Blank ! << Personally, I hate um ! Then Think there called Mitche Or Michele . <, Cant remember But think there Mitchel what I use . << My machinist just hand's um too me ??? Ive Never seen the Box .

But this is what I use on Vw motor's Mitchel Aluminum Push rodd's . Same ones used By V8 Builders . There Aluminum , And Expensive . But much easier too work with than Chromoly .

Now On V8 Motors . << Havent Built one in 15 Year's ? It's been a while ?

But Valve Geometry comes intoo play here . Push rodd lenght's are determined by Valve Geometry . << determines the Lenght .

Way I do it is I build an Adjustable Push rod . << Get an approximate Lenght, then Cut tipp off a stock Push rod , Thread it with a Tapp . Then use a Bolt with a Modified head << That duplicate's a Push rod End , Then a Locking Nut ! Thread Nut on the bolt . Then screw bolt intoo the threaded end of the modified stock Push rod . Via adjustable Push rod, with locking nut !

Use Adjustable Push rodd too Get your valve Geometry , correct ! When Valve geometry is correct using the adjustable Push rod . You lock the Nut on it . << Push rod Lenght !

Basically on Vw motor ! I turn the motor over until the Valve spring is 1/2 way thru it's travel . << Have too determine when spring is compressed Exactly at 1/2 way . Then I look at the Valve tipp adjuster <<< Should be in a direct straight line with Valve stem . << Way Vw valve geometry is aquired ? >>> On V8's ??? I dont know !

Hydraulic Lifters ? I dont know ? But do know this ! I would find out . Valve geometry is important ! <<< Difference atween Good motor and a Badd motor ! Not a Guessin game ? Aftermarkrt head's, Valves, Rocker's, the Decking And Surfaceing , Of Block and Heads all affect what lenght your Push rod's need too be too Aquire a Proper valve geometry .

Now on Actually Cutting Aluminum Mitchel Rodd's << Expensive and it's a One shot Deal . You mess um up ! It's over , Buy new sett ! <<, Easier too work with than Chromoly ? But I hate Chromoly Push Rods ! Far as im concerned, chromoly is Only good for Full on Race motor's , Runnin Fuel !

Napa has Book on V8 Chevy rebuild's << Probably has Section on Valve Geometry . There like 20 Buck's I would buy one ?
Well worth the money ! Considerin money that goes intoo Rebuildin a Motor ?

Post again with what Type of Push rod your Gonna be Usin ? << This will determine how I cut them Too lenght . I can Go over how I cut mine, if you like ?


Sean

[71C10]

Originally Posted by Sean's

Yeah , Ok 2 basic types of aftermarket Push rod,s ! Chromoly <<< Touted as being the Blank ! << Personally, I hate um ! Then Think there called Mitche Or Michele . <, Cant remember But think there Mitchel what I use . << My machinist just hand's um too me ??? Ive Never seen the Box .

But this is what I use on Vw motor's Mitchel Aluminum Push rodd's . Same ones used By V8 Builders . There Aluminum , And Expensive . But much easier too work with than Chromoly .

Now On V8 Motors . << Havent Built one in 15 Year's ? It's been a while ?

But Valve Geometry comes intoo play here . Push rodd lenght's are determined by Valve Geometry . << determines the Lenght .

Way I do it is I build an Adjustable Push rod . << Get an approximate Lenght, then Cut tipp off a stock Push rod , Thread it with a Tapp . Then use a Bolt with a Modified head << That duplicate's a Push rod End , Then a Locking Nut ! Thread Nut on the bolt . Then screw bolt intoo the threaded end of the modified stock Push rod . Via adjustable Push rod, with locking nut !

Use Adjustable Push rodd too Get your valve Geometry , correct ! When Valve geometry is correct using the adjustable Push rod . You lock the Nut on it . << Push rod Lenght !

Basically on Vw motor ! I turn the motor over until the Valve spring is 1/2 way thru it's travel . << Have too determine when spring is compressed Exactly at 1/2 way . Then I look at the Valve tipp adjuster <<< Should be in a direct straight line with Valve stem . << Way Vw valve geometry is aquired ? >>> On V8's ??? I dont know !

Hydraulic Lifters ? I dont know ? But do know this ! I would find out . Valve geometry is important ! <<< Difference atween Good motor and a Badd motor ! Not a Guessin game ? Aftermarkrt head's, Valves, Rocker's, the Decking And Surfaceing , Of Block and Heads all affect what lenght your Push rod's need too be too Aquire a Proper valve geometry .

Now on Actually Cutting Aluminum Mitchel Rodd's << Expensive and it's a One shot Deal . You mess um up ! It's over , Buy new sett ! <<, Easier too work with than Chromoly ? But I hate Chromoly Push Rods ! Far as im concerned, chromoly is Only good for Full on Race motor's , Runnin Fuel !

Napa has Book on V8 Chevy rebuild's << Probably has Section on Valve Geometry . There like 20 Buck's I would buy one ?
Well worth the money ! Considerin money that goes intoo Rebuildin a Motor ?

Post again with what Type of Push rod your Gonna be Usin ? << This will determine how I cut them Too lenght . I can Go over how I cut mine, if you like ?


Sean

Click here for the translation.

[hotroddr]

A low-buck way to get it right is to buy one of those $12 length checkers that fits on the rocker stud and then use a small pice of threaded rod/nut stuffed in the end of a stock push rod with the end cut off. You can then order the length you need. Bill

[IanRiordan]

Manley list pushrods in 50 thou increments.

[Sean's]

There You Go 71c10 ! Super Cool ! What you needed ! Translation from German too English ? Or is that American ?

But Super cool ! lott of People put a motor together , spend no time on Valve geometry !
Stock Motor you might get away with usin stock push rodd's ???
But this is where You Slow down , Get thing's Right !
Dig in and Study on it Some . Result's are well worth it !
Thank's ! I enjoyed Readin it ! V8's are Lil different than what Im use too !
Im still workin on figurin out a v8 build !
lookin hard at A Willy's Jeep Truck sittin in these peoples Yard , 2 Flatt tires!
Then again Im still lookin Around .
P.s. Got ant Url's for degreeing Camm's in V8 Motor's ?

Sean

[71C10]

Originally Posted by Sean's

There You Go 71c10 ! Super Cool ! What you needed ! Translation from German too English ? Or is that American ?

But Super cool ! lott of People put a motor together , spend no time on Valve geometry !
Stock Motor you might get away with usin stock push rodd's ???
But this is where You Slow down , Get thing's Right !
Dig in and Study on it Some . Result's are well worth it !
Thank's ! I enjoyed Readin it ! V8's are Lil different than what Im use too !
Im still workin on figurin out a v8 build !
lookin hard at A Willy's Jeep Truck sittin in these peoples Yard , 2 Flatt tires!
Then again Im still lookin Around .
P.s. Got ant Url's for degreeing Camm's in V8 Motor's ?

Sean

Here is some reading for you. Comp Cams