If you have AFR 185's and big cam please read

[ZarnAutomotive]

I got a 347 with a nitrous cam and 185's I need to know what length pushrods are you running, the stock ones are to short, I also have stud mount rockers

 

[RIXX93GT]

I just checked my 185's with FTI cam and it looks like stock or maybe just slightly longer, but Im going with 6.250" long.

 

[ZarnAutomotive]

ttt

 

[ZarnAutomotive]

TTT

 

[Ranchero5.0]

Ditto that, stock length here... Geo looks good. less than 1/8" sweep across the valve...

Jamie

 

[Rick 91GT]

Best thing is to do what Jamie talked about, mock it up and see how the rocker sweeps across the valve tip...only true way to make sure you have the proper length pushrod. You can also purchase a push rod length checker from JEGS or SUMMIT..

 

[ZarnAutomotive]

ranchero do you have a 347? I can't see how you guys are still running stock push rod length, I have never used a pushrod length checker before. I anyone else ? I thinking around the 6.40 length is needed for this application

 

[RIXX93GT]

Just got in from adjusting my valves with 6.250 length pushrods. The sweep starts just inside of center and travels just past centerline of valve tip. I have a pushrod length tool and I dont see a need for any longer pushrod. If anything the optimal length looks like it would be 6.300.

 

[RIXX93GT]

I got a 347 with a nitrous cam and 185's I need to know what length pushrods are you running, the stock ones are to short, I also have stud mount rockers

How big is your cam? I have .563 lift on Intake whats yours like?

 

[ZarnAutomotive]

To be honest I don't know. I had friend that knew someone thats was selling a cam from a car that ran 10's with NOS so i bought and my buddy installed it when he built my 347, all he told me its was a big cam, the problem is I the rockers arms are real loud and the cylinder 1 rockers have fallen off twice, The valves are adjusted right I went over with 2 tech support guys ,So I guessing if there that loose I need more just .5 larger right?

 

[Michael Yount]

Zarn - what we're trying to tell you, gently, is to stop 'guessing' and get (or make) an adjustable pushrod so you can optimize the length for proper valve train geometry. You want the tip of the rocker to stay as close to the center of the valve stem throughout it's travel as possible. A light test spring on the valve for the mock up makes things easier - and use grease or dye/ink to see exactly where the tips are hitting. There has to be some movement from center - the arc of rocker movement requires that - ideally it should start slightly inside of center, swing to slightly outside of center at mid lift, ending up back slightly inside of center at peak lift. Other's pushrod lengths won't help your combination - when you get to this level of dimensional detail, every combo - including those with 'identical' parts, is different. With your symptoms, you clearly have something that is way wrong - measure and work the problem. No need to guess at it.

 

[Rick 91GT]

Zarn - what we're trying to tell you, gently, is to stop 'guessing' and get (or make) an adjustable pushrod so you can optimize the length for proper valve train geometry. You want the tip of the rocker to stay as close to the center of the valve stem throughout it's travel as possible. A light test spring on the valve for the mock up makes things easier - and use grease or dye/ink to see exactly where the tips are hitting. There has to be some movement from center - the arc of rocker movement requires that - ideally it should start slightly inside of center, swing to slightly outside of center at mid lift, ending up back slightly inside of center at peak lift. Other's pushrod lengths won't help your combination - when you get to this level of dimensional detail, every combo - including those with 'identical' parts, is different. With your symptoms, you clearly have something that is way wrong - measure and work the problem. No need to guess at it.