Pushrod length

[bjopau]

How do I calculate the pushrod length?

Now I have:
crane hmv 282-2 cam.
Hydraulic lifters
rockerarm unknown, probably a bit stronger than stock, but in stampet steel.
Pushrods 7,5" (5/16 tube with a little bowl at the ends)
stock 1976 heads.
stock valves/springs

the changes.
comp cl 20-225-4 cam
hydraulic lifters
Sealed Power ZR862 and ZR861 rocker arms.
the heads are planed .040
Milodon 45645-8 - Milodon Street Stainless Valves 1.60
Milodon 45640-8 - Milodon Street Stainless Valves 2.02
COMP Cams 995-16 - COMP Cams Valve Springs
740-16 - COMP Cams Steel Valve Spring Retainers

 

[flyfish]

The only way to know for sure is to buy a pushrod checker (~ 12 bucks), measure, and mail the pushrod checker to a company like Smith Brother Pushrods…That’s what I did.

 

[340sFastback]

Summit sells some pushrod length checkers for cheap:

http://www.summitracing.com/search/?keyword=pushrod length checker&dds=1

I measured mine with one and took it to a local engine shop and they told me what to order. Comp Cams has many many different length push rods you can by off the shelf.

 

[Rob Eppler]

Take a stock push rod and cut it in half [or a convienent place] and thread it to 1/4 X 20 or 10/32 or what ever. place some all thread in the middle of it and "adjust" the push rod to the desired length! Then using a dial caliper measure the over all length and bingo! Do not forget to spec. which ends, wall thickness and diameter you may want. Keep this in your tool box for future builds!

 

[moper]

yup. No calculations. You measure for it. And you should measure several cylinders...

 

[bjopau]

thanks.
that seemed like a handy tool.