3/8" pushrods

[c9zx]

I'm ready to order pushrods and I want to order 3/8". Block deck is 10.150" and square, heads are TFS un-milled, HS rockers (ball and ball oil through pushrod), BAM solid roller lifters, intake is ED RPM. The pushrod hole in the intake is .625" which leaves .125 in all directions with a 3/8" pushrod. I think the pushrods will clear the intake. However, I'd really appreciate those with a similar build to share your experience using 3/8 pushrods.

I'd also like input on wall thickness for the 3/8" pushrods as well as input on the oil hole size in the pushrod (restricted or not). My instincts are saying not to restrict but I'd like your input on the question.
Thanks, Chuck (S)

[fairlaniac]

Keep in mind one thing. Chances of any or all of you pushrods to position centered in the pushrod bore of the intake are slim to none. As the valve train goes through it's motions, the middle of the push rod may get close to rubbing or will rub the bore. All just FYI.

[blykins]

As I mentioned in text, you should have room, but you need to buy a 3/8" pushrod length checker and check all 16 holes.  In theory, you should have room, but the reality is that nothing works out like that.  You will have some that have plenty of room, some are close. 

With a solid roller, I like to use the biggest/thickest pushrod I can get.  In your case, if you can fit a 3/8", then a 3/8" .135" wall pushrod.  Don't worry about the oil hole. 

In addition, prime the oil pump with the intake off, because you'll probably end up modifying the lifters to push enough oil to the pushrods.   I have a video on how to do that if you need it. 

[c9zx]

Thanks everyone. Brent, you had told me this before but thanks for repeating it. My NVRAM is not so NV anymore. Chuck (S)

[Barry_R]

Kinda backing up Brett's comments.  On solid roller stuff I consider that .135 as a minimum, and prefer .165 wall if I can get it. 
Solid roller stuff needs to be as stiff as possible.  With lash on a solid roller I prefer not to have oil holes in the pushrod unless using the T&D race rockers where pushrod oiling is mandatory.

[c9zx]

Barry, Thanks for the additional information. I ordered 3/8 .141 wall from Smith Brothers this morning. On a side note, when double checking everything before ordering, I spoke with the people at BAM lifters about cup size. They said it is some special design allowing the use of 5/16 or 3/8 ball ends. I had never heard of that. Chuck (S)

[mike7570]

C9zx, I’m using 7/16 Manton pushrods which fit after a little clearancing. I marked the push rods with blue dye and rotated the engine over to find any interference, then opened the passages for clearance. The push rods were fine at lift but rubbed when on the cam base. The dye left tell tale marks in the intake and on the push rods which made it easy to know where to adjust. Different heads and rockers will have more or less interference and it’s a good idea to check during assembly.