440, what length pushrods do I need.......

[bandit67]

Hi Guys, Mopar newbie here putting together my first big block 440. Did not have a complete engine so not sure what stock length pushrods were used , which is what I think I need. The block is a 67 casting and I m using the 915 heads with stock rocker arms. Stock flat tappet cam used. In looking to purchase pushrods I see several lengths available . I THINK I need 9.315 s, does that sound correct.....thanks......

 

[Frank Mopar]

9.315 is correct

 

[RJRENTON]

To be ABSOLUTELY sure, contact:
Smith Bros. Pushrods
2895 SW 13th St.
Redmond, OR 97756
1-800-367-1533
or go to rheir website: www.pushrods.net
They make custom made rods and will able to confirm or recommend a push rod for your application.
BOB RENTON

 

[turbine68rt]

Are you starting over with a new cam and lifter set? In that case you'll need to determine proper preload according to that respective manufacturer's specified window. Usually between .020-.040. Since the stock rockers aren't adjustable, a custom length pushrod may need to be ordered if the stock length is producing too much or too little preload.

 

[BLK 68 R/T]

Yep gotta measure, especially if the block was decked, heads shaved, thick/thin head gaskets, etc.

 

[451Mopar]

If your looking up 1967 440 you may see listings for a slightly longer pushrod than say a 1970 model. The '67 used a different lifter and I think the lifter seat was lower requiring a slightly longer pushrod. those stock '67 pushrods had a smaller end where it goes into the lifter also.
If using aftermarket / newer style lifters, then just look up the listing for a later model 440.
Ii you want to be really precise on lifter pre-load, you will have to use an adjustable checking pushrod to measure the length.

 

[65wgn440]

Measured mine and came out to 9.25". Standard '70 block, .010" milled '67 heads, MP solid flat tappet. Got them in that length from Comp Cams.

 

[bandit67]

Thanks, the block was decked and heads were milled......how much, don t know. The cam and lifter kit is from Lanati, around .480 intake and .513 exhaust I think. Head gasket is a big thick .39 Fel Pro. I assume those motors were assembled with the thin metal gaskets that were used in the sixties and with the decking I would be CLOSE to stock. But, you prolly correct , I need to measure. But knowing the 9.315 was original...i now have something to work with. ....thanks all

 

[beanhead]

Thanks, the block was decked and heads were milled......how much, don t know. The cam and lifter kit is from Lanati, around .480 intake and .513 exhaust I think. Head gasket is a big thick .39 Fel Pro. I assume those motors were assembled with the thin metal gaskets that were used in the sixties and with the decking I would be CLOSE to stock. But, you prolly correct , I need to measure. But knowing the 9.315 was original...i now have something to work with. ....thanks all

Okay you should measure. Comp's adjustable checking pushrod is about 20-something dollars...you 'might be fine' just buying a set off the shelf as the lifters have a range of acceptable preload, personally I'd opt for the cheap insurance every time and check 'em.

 

[Wietse]

I am not sure but are lifter heights from various manufacturers all the same? Guess not.
If you know the compressed thickness of the head gasket you are going to use you can do a pre-assemble with head bolts snug (not torqued up, or use old bolts) and use a length checking pushrod to confirm the correct length. (after confirming length you need to substract the head gasket compression from the found length)
Don't forget to add the recommended pre-load for your lifters.
You might get away with a standard length, if not, contact Smith Brothers as recommended above.
I also just received my push rods from them and received all support as required from them to make the right choice when ordering.
Since you are using stock rockers you will be using a ball/ball configuration which saves the hassle of determining the "effective length" as with ball/cup type.
Just get the right length checking push rod, like below example.
https://www.summitracing.com/int/parts/cca-7704-1
Check the adjustable length is in the ball park of what you require.