As some of you may remember I have done some dyno testing on motors and different parts over the past twenty tears or so. The last motor, 527 C.I. broke a 3/8 x.083 wall pushrod in the middle on a pull causing some damages the the other pushrod and the roller lifters. I fixed the motor and ended up replacing those pushrods with a set of 3/6x.120 heat treated set, that change was done on a DTS dyno and we saw a 2 ft. lb and 2 hp increase at 4100 RPM and a 8 ft. lb and 8 HP increase at 5400 RPM, according to the dyno sheets. The combination on this motor is 1968 440 block with the lifter bushed, Indy SR heads(M.W. ports) Comp Cams solid roller [Email]275@.050[/Email] Int. [Email]282@.050[/Email] EX .440 lobe lift on both, T&D 1.65 rockers, 260 lbs. seat pressure 670 lbs over the nose. 4.380 bore with 4.375 stroke with Manley 6.943 long H beam rods with stock Mopar rod journals, Ross flat tops pistons with valve reliefs and 13.0 to 1 comp. Motor makes peak power between 6100 RPM and 6400 RPM now with the new pushrods. My question is what size pushrods (diameter and thickness) are you guys using and where does your motor make peak power? I have a low deck street stroker motor that makes peak power on the dyno at 5800 RPM but pulls like crazy to 7500 RPM( I get scared and shift it before it starts to lay over
) in the car
I have not had the new 527 motor in the car yet so I don't know how it will do or pull to in the car. I'm thanking that maybe a bigger diameter and thicker wall pushrod will help move the peak power up even more
, what do you guys have and do
All comments appreciated
EDIT.Current pushrods Manto Series V are 3/8 diameter, .120 wall thick, 5/16 ball and ball 9.980 long
I forgot to mention the spring pressures are 260 lbs on the seat and 670 lb. over the nose. What size diameter, length and wall thickness are you guys using