I need a little help for getting the correct 3/8” pushrods for my upcoming ‘69 350” Oldsmobile build.
Edelbrock heads have guide plates for 3/8” pushrods but I cannot find the correct length I should order.

heads https://www.summitracing.com/parts/edl-60519


Cam https://www.summitracing.com/parts/lun-10420702lk

rockers https://www.summitracing.com/parts/csp-s5016

My plan is to use Mahle flat top pistons and possibly mill the Edelbrock’s if necessary to achieve 10.1 compression since the Felpro gaskets are pretty thick.

Can anyone provide a recommendation for the pushrods?

 

Smith Brothers Push Rods. Just Google them. FYI, if you end up needing 9.2" push rods, I can hook you up. Made a measuring mistake, so they are new in the box.

 

You need to order pushrods last. On a hydraulic cam/lifters get them just long enough to provide minimum preload of the lifter plunger. Measure before you put the intake manifold on.

 

Agreed, especially since you said you will be milling the heads. You will need to measure the length needed after all the machine work is done and the heads are bolted onto the block.

 

X2. I offer all different size pushrods in a restricted style.
3/8” are $240.00 shipped and are made here in Florida.
i can also help with the Mahle piston kit as well.
Thanks.

 

I made the same mistake as ajr2820 and have a brand new set of Smith Bros. 3/8" x .083 with the oil restrictors that are 7.95" long. I had an interference issue with the pushrod holes in the ProComp heads so they have some minor scuff marks where they rubbed. They were only used for mock-up/assembly purposes; the engine was never run with these. They're kind of pricey, but I'll make you a good deal just to get them to someone who can use them. Here's a pic:
Rodney

 

Being I’m using Edelbrock heads and adjustable rocker arms, I didn’t know if there was a standard length push rod and you have enough adjustability in the setup I’m using.
I read an old post that Edelbrock recommended a 9.8” pushrod but I think that was referencing a 455

 

Ok that good you have adjustable rockers. You still need to be within range and you won't know what that is till you measure.... My brother also fell into the trap, Oh these are the pushrods you need for this block and this cam and these heads..... The ones sold to him are now swizzle sticks and he had to measure and buy another set.

 

I’ll be reaching out for pistons in a couple weeks.
Thanks

 

As said, you measure pushrod length after the long block is assembled. You can guess a length, but it's not likely to be correct. The problem is not all that many Olds are build (compared to chevy/ford) and there's more variation in Olds parts, so a "standard" or "recommended" pushrod is seldom correct.
It adds a week to your build schedule but, well, it's the right way to do it.

If you haven't measured pushrod lengths before, get a pair of checker springs, one or two adjustable pushrods in the 7"-9" range, and a tool to change valve springs with the head installed (and a compression checker with the schrader removed to pressurize the bore while changing springs). Check with the checker springs, not your real springs.

You might not need to mill the heads to get the compression, but you might need to mill them to get them flat. Also check the intake surface! My latest set of ebrock heads had a 0.002" trough.

FWIW, my pushrod length with a flat tappet voodoo cam, 403 block with ~0.010" cut, Ebrock heads with ~0.010" cut, 0.040" cometic gaskets, and Harland Sharp S5016's was 8.28" (Comp 7161), I also had slight interference with the bottom of the pushrod hole in the head with 3/8 pushrods. Best to go ahead and open those up. Just grind out some material towards the intake - that's all solid aluminum there, as long as you don't wander off towards a port.

 

Thanks for the feedback. Seems to be a lot of inconsistencies with the Edelbrock heads but pretty minimal corrections in lieu of trying to get my # 5’s to work as well.

 

Hello scj64,


Here at Bernard Mondello Racing Enterprises we offer everything you need to do this job correctly!

We sell the Edelbrock cylinder heads and have the custom tapered reamer for the bottom of the pushrod holes needed for modification for small block use.

We also sell the correct (and modified exclusively for us) Harland Sharp S5016 roller rocker arms... If you buy these rocker arms as they come, they will not clear the rocker stud radius for the rocker to go low enough for proper pushrod length.

We can surface the cylinder heads for proper small block combustion chamber size and we sell the correct Cometic MLS head gaskets needed, along with proper 3/8' adjustable mock-up pushrod for correct pushrod length.

We sell the correct .095 wall 3/8'' pushrods heat treated for guide plates with our .040 oil restricted ends (any length odd or even lengths).

We do all this in our complete racing cylinder head shop and we are a known Oldsmobile Specialist.

Thank you in advance,

Bernard Mondello Racing Enterprises
1441 Pomona Rd., Ste 16
Corona, California 92882

www.bernardmondelloracing.com

 

Thanks for reaching out Bernard. I presume you offer port matching a 7111 manifold to your heads?
It would be nice to buy heads, rockers, manifold and related gaskets ready to bolt on. I’ll take everyone’s advice and measure pushrods after the heads are bolted on.
I’m 3 to 4 weeks out on ordering engine parts. What’s the wait time at your shop?

 

Hello scj64,

We're running about 10-12 weeks with our current work load?

If that's okay, you may want to call me @ 951-371-1432 for all the information that's needed when doing this job correctly!

Also you'll need to know you cannot use a mechanical fuel pump with these cylinder heads.. Without major modification?

Thank you,
Bernard Mondello Racing Enterprises

 

SJ,
Not sure how close you are in Md but if you need any help feel free to give me a shout