[randy]

i am sort of lost with this one i am rebuilding a 440 30 over with 906 heads mopar purple shaft cam with 474 lift and it will be hydraulic lifters i need to know should i go with the original 3/8 diameter are should i go with the 7/16 diameter and the length i am not sure about i dont have any of the old one to measure them by there so many on the market these days to buy i wont to get the correct diameter and the correct length and what is a good brand for me to buy. thank you.

[Eddie]

Thats a pretty mild setup. You have 3/8 stock from the factory? That size should be plenty strong enough, especially if Chrome-Moly one piece, instead of the flat sheet steel rolled pushrods the factory used I like these Smith Bros. 4130 Chrome-Moly. But there are other ones that are equally as nice. www.pushrods.net or http://chucker54.stores.yahoo.net/pushrods2.html Length may or may not be factor, depending upon machine work to the block and how many aftermarket parts are used in the engine build. You can either rent or purchase an adjustable 'checking' pushrod from either supplier and 'mock-up' one cylinder during pre-assembly. Then you simply tape it up, send it back to them and they will custom make a set to your 'checking pushrod' length.

[dave-r]

I take it you are using stock rockers?

If so use stock pushrods. No need for anything more with that cam.

[dave-r]

9.32 inch is the length on the RB block I think. Round at both ends of course.

Normally you will find that only the ones with a cup end (for adjustable rockers) will come in different lengths.

[dave-r]

If you do have adjustable rockers fitted use the adjustable pushrods or the "cut to length" type.

You need to make them the correct length to give you only one adjuster thread showing on the underside of the rocker when set to the correct preload.

[randy]

yes i am using the stock rockers.Thank for all the information that a big help.