push rods how long

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Jun 12, 2010 | 10:00 PM

gregs86

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From: Pace fl

push rods how long

hello just thinking someone may have the same set up
I have the zz4 short block with AFR 180 heads with a roller cam from tpis it hasnt arrived yet or should i just get a adjustable push rod and test it figure somebody would have the answer

Jun 12, 2010 | 11:19 PM

John A. Marker

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From: Dublin CA

I used hardened push rods from summit...part number SUM-1457200 they are 7.2 inches. Stock is 7.8 inches. You have to use the shorter rod because of the total height of the roller lifter.

Jun 12, 2010 | 11:25 PM

Pete K

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Mock it up and measure it. If the AFR have valve lengths that are .100 longer than stock, you will need something in the 7.300 range. Nevertheless, don't guess.

Jun 12, 2010 | 11:42 PM

GREGGPENN

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From: Overland Park Kansas

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Quote:

Originally Posted by Pete K

Mock it up and measure it. If the AFR have valve lengths that are .100 longer than stock, you will need something in the 7.300 range. Nevertheless, don't guess.

That's probably not too far off. Mine were angle-milled 9cc. At .008" per cc, that's .072" removed. My 195's ended up taking 7.2" (with that much removed). IOW, mine were milled close to the same amount as you think should be added.

(I'm going under the assumption that AFR uses the same core before CNC'ing the 180/195 heads.)

Jun 12, 2010 | 11:47 PM

tpi 421 vette

Melting Slicks

Joined: Mar 2002

Posts: 3,107

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From: S.L.C. UT

Quote:

Originally Posted by John A. Marker

I used hardened push rods from summit...part number SUM-1457200 they are 7.2 inches. Stock is 7.8 inches. You have to use the shorter rod because of the total height of the roller lifter.

The hyd roller engines have a stock length of 7.200" The flat tappet cams came with a 7.800" length. If you are running the stock ZZ4 cam, there is a good chance you will need a 7.200" pushrod. Small base circle cams create the need more than anything for shorter pushrods. And most mild cams don't have a greatly reduced base circle

Jun 13, 2010 | 11:35 AM

MK 82

Melting Slicks

Joined: Feb 2008

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From: Palm Beach

Just did a cam swap on my LT4. Put in a CC503. Had to go from 7.2 to 7.1. Using the adjustable pushrod is the right way.

Jun 13, 2010 | 06:23 PM

JAKE

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From: Kempner Texas

DO NOT rely on what someone else is running. Measure then buy what your combination calls for.

Jake

My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!

Last edited by JAKE; Jun 13, 2010 at 06:26 PM.

Jun 13, 2010 | 06:44 PM

surfer93

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w/Jake.

BTW: Congradulations to your son Jake.

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Jun 13, 2010 | 07:56 PM

John A. Marker

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Joined: Mar 2004

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From: Dublin CA

7.2" should work for you. Same engine as mine (ZZ4) with AFR 180 heads (same as mine). Cam should not make a difference. Roller lifters should be the same height.