pushrod length/measuring question

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matty wardle

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hi,i,m buildind a 451 stroker low deck,the bottom end is complete and i,m up to buying the pushrods,the engine is using a comp cams hydraulic ex 285 hl,its using the hughes 1.5 rocker system,ok so do i just buy standard oem 383/400 pushrods or do i need set up and measure,i have a adjustable pushrod checker which i purchased,can someone give me advice on all this?????
 
You want to check before you go out and buy a off the shelf part. What your shooting for is 1 to 1 1/2 threads showing below the rocker arm after you set the lifter preload.
 
You need to check it on the base circle, and be aware of what you lifter preload needs to be too.
 
so let me get this straight i take the number 1 cyl to top dead center with both valves closed insert my checking pushrod,adjust it to zero lash with 1 thread protruding below the rocker,then i measure this and add 30 thou to the overall measurement for preload(this is what my comp cams paperwork says regarding preload with there lifters)i dont have a solid checking lifter,does this method sound right,also when i measure from the tip of the ball to the top of the cup,what do i add on for the other half of the cup,and when comp advertise there pushrod lengths,does it take into account the other half of the ball protruding from the cup?????????
 
Yes - that's basically it. TDC on compression stroke. It depends...lol. When I measure and call Smith Bors. I measure overall length and tell them what radius the ball and cup need to have. They take the info and account for it.
If you are using Comp's ball method then you will need to subtract the diameter of the ball from your figure. So fit the adjustable pushrod in place and snug the pushrod's lock nut. Then remove the adujustable pushrod from the engine by backing off the rocker shaft. Then drop the ball in the cup and measure. Then subtract the ball diameter from the overall length.
 
now for the tricky part,where to get a 5/16 ball bearing,is there just a figure for half the ball bearing????????????
 
Eh did you ever get this figured out?

Does anyone know what the pushrod length would be? Or even a guesstimate?
Cheers!

-Shiny
What's the engine for you? What heads ?
The best bet would be to buy a adjustable pushrod for checking proper length.
 
What's the engine for you? What heads ?
The best bet would be to buy a adjustable pushrod for checking proper length.

I bought my "67 Barracuda convertible back that I sold 30 years ago. It came with a brand new really well built 451 stroker shortblock. Debating on what heads to get for it. Want to make big power as the car is back halfed with 4 link coilovers etc.
What pushrod kit is the one to get?

-Shiny
 
1/2 a ball bearing? I swear, some of you guys would make whackin off difficult.
 
I bought my "67 Barracuda convertible back that I sold 30 years ago. It came with a brand new really well built 451 stroker shortblock. Debating on what heads to get for it. Want to make big power as the car is back halfed with 4 link coilovers etc.
What pushrod kit is the one to get?

-Shiny
Look or call 440 source they'll have the single check pushrod.
I'd Probably advise trickflow 240 or 270 heads to start for making great power. Sounds like a nice build.
 
Look or call 440 source they'll have the single check pushrod.
I'd Probably advise trickflow 240 or 270 heads to start for making great power. Sounds like a nice build.
Thanks man!
I was thinking those but none available at all eh. I known of a set of Stealth heads locally for a deal, used but not many miles on them and only two years old. But would like MW port heads.

-Shiny
 
Thanks man!
I was thinking those but none available at all eh. I known of a set of Stealth heads locally for a deal, used but not many miles on them and only two years old. But would like MW port heads.

-Shiny
Well there's plenty of proof a stealth head can make good power, I had a set of stealth heads before I bought the trickflows and used them in trade for my Dana 60. How much power are you looking to make by the way?
The man who post above me IQ52 is worth asking and reading his threads, blow your mind type stuff from him
 
Well there's plenty of proof a stealth head can make good power, I had a set of stealth heads before I bought the trickflows and used them in trade for my Dana 60. How much power are you looking to make by the way?
Oh nice. 600+ would be great.
Not sure how far out the TF 270s are, alot of parts are on backorder right now eh. Maybe I should just get these Stealths. And then get rockers and find an intake, hopefully. And pushrods of course. Ha!

-Shiny
 
watch the utube vid "pushrod geometry for engines" by Straub. its the one with the yellow rocker. they want at half cam lift you want the correct pushrod length to where the rocker is at a 90 deg right angle to the valve stem for the most area under the curve. & I think add/subtract for preload/lash amounts
 
I guess I’ve been checking pushrod length wrong for 20 plus years now ! I’ve never seen or heard of any of this mess in this thread ! Zero lash , make the rocker arm make contact on the valve in the center of the valve, through out the travel of the rocker arm ! When that happens pull out your adjustable pushrod and measure it ! Order the pushrod that is that length ! 20 plus years of doing that very thing ! Never had a problem ! Obviously, I have a lot to learn on measuring pushrod length
 
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