MikeGyver

iTrader: (5)

Sorry, I don't know what I was thinking. My morning pill must have not kicked in yet when I posted.No, I never understood that you already have the tool. I hope you accept my apology.

Feed

iTrader: (2)

It doesn't really matter what torque spec you use when using the pushrod length checker, rockers will be tight. You are using the known minimum length of pushrod checker + desired preload amount + thread pitch of length checker X number of turns to get to zero lash. Thread pitch is .05"

07NBSChevy

I was just giving you a hard time.. no wories man. Heck, I wish I new more about getting the desired pushrod length, and I was an engine tech for GM back in the day. Tho it was something I never did because I never did cam swaps at the dealership.

07NBSChevy

I was referring to once I have the desired pushrod length and preload and was going for the final torque.

07NBSChevy

Also, I forgot to ask. Is it necessary to measure all 16 pushrods for each cylinder or do I just need to do one cylinder? I am currently going to use cylinder #1 and measure intake and exhaust.

07NBSChevy

So messed around with it today and started with 7.350"
-On intake I got 22 ft lbs at 1-1/2 turns which is 0.0705 Preload.
-On exhaust I got 22 ft lbs at a tad over 1-1/2 turns which is roughly 0.075 preload

I tried 7.375" and got 22 ft lbs at 1-7/8 turns which is 0.135 preload and way to much. Also tried 7.325" and it was to short.

So looks like 7.350" pushrods and 0.070-.0075 preload is going to be it. I will check again tomorrow since I am a bit tired and do not want to do this twice.

Beatdown Z

iTrader: (18)

Sounds like you got it figured out.

Beatdown Z

iTrader: (18)

I don't know if ARP studs have a different thread size than factory bolts, but if they do you can just a factory bolt to figure out pushrod length, then throw the stud back in for final assembly.

07NBSChevy

I did figure it out. Thanks for all the help guys. The ARP Head Studs, #234-7207, The nut is a 24 threads per inch. I did try today with torquing them down to 25 ft lbs and noticed I got another 1/32 or less, more of a turn, which is not really going to effect much. Either way both Intake and Exhaust valves I got 25 ft lbs between 1-5/8 and 1-7/8 turns, at least on cylinder 1, so 0.076375 on exhaust and 0.088125 on intake. Even if I go over .083 preload shouldn't hurt, I read that .070 thru .090 preload from center travel of 0.08307085 is ideal for up to 6200 rpm. I will triple check everything once the pushrods come in. I am going with Comp Cams 5/16 7.350" .105 wall. I really wanted Manton 5/16 Series 3 .118 wall pushrods but they said there is some wait time since they were not stocked, and the Mantons were $30 more.

Can someone explain to me the purpose of using tapered pushrods over straight ones?

All you had me wondering about the arp difference on the ARP so I did a test. I am hoping it works out in my favor and maybe this is why ARP recommends 25 ft lbs instead of 22.

So I used the 7.350" pushrod checker and used the ARP stud and started with the exhaust vale. I got 25 ft lbs at 1-5/8 turns. I found my stock rocker bolt and did the same thing at 22 ft lbs. I got 22 ft lbs at 1-5/8 turns. I moved on to the intake valve now. With the ARP Stud I got 25 ft lbs at 1-7/8 turns. Used the stock rocker bolt and got 22 ft lbs at 1-7/8 turns. So I am wondering if the added torque equals out with the ARP over the stock bolt.

TXsilverado

iTrader: (19)

Why go through all this crap if you have a length checker? The best method is to just use a length checker. The bolt turn method is a guess at best IMP