fastlane40

Is there a set length of pushrod for a tall deck motor.Is it influenced by lifter type or rocker style?I need a set for a tall deck.Thanks

SkiDoc

iTrader: (4)

You need to get an adjustable pushrod(will micro adjust.) Put the push rod in. Mark the top of the valve stem with pencil. Assemble the rocker arm properly and turn the motor over.
Where the roller on the rocker contacts the valve stem there will be a distinct mark. You want this mark to be in the center of the stem for the best geometry. Through trial and error through changing the pushrod length you can accomplish this. When you get the proper length, measure it and order the correct length. Eric

Young Performance

There is no set length for any motor. There are too many variables. It is affected by valve stem length, cam, lifters, rockers, if the block and heads have been milled, etc, etc, etc. Eric gave you the correct way to measure them in the above post. Just simply determine what length you need and order that length. If it is a twin, be sure to measure both engines. Hope this helps, Eddie.

MESABALANCING

If you don't have an adjustible pushrod you can take a pushrod cut it and thread the inside of the tube and use a piece of all thread between both pieces to adjust the length you need to make sure you use a soft spring or a inner valve spring for the testing because the spring press will break even the nicest adjustable pushrod good luck.www.mesabalancing.com

fastlane40

Thanks for all the help.

ROTAX454

The most overlooked issue when measuring for the correct pushrod length. Great info.

Once you have determined the correct pushrod, this manufacturer is tops.
http://www.trendperform.com/

jeff1000man

Before I had the adjustable pushrods, I used to take a pushrod that was to short and stick it in the hole and lift the rocker until it was in the proper position, take a tape measure or ruler and add the distance to the length of the shorter rod.

If you know what you are looking at while you are measuring then it usually works.

You have to measure both engines because sometimes there are different types of heads, machine shops install different valves, They could have had a valve job that lowers the valve into the head and raises the stem.

Not always a problem, but it sometimes shows up.

Good luck with your project.

38tg

manley make a neat inexpensive tool that assists in measuring push rods. you don't have to rotaye motor over.