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Hi All,
Hopefully not to much of a dumb question but will a standard pushrod length fit my 84' 351 stroked to 393 or do I have to use a length checker & order custom length pushrods? The block has been decked & I will be running AFR185's with Scorpion billet 1:6 rockers & a Comp Cams XE284 hydraulic flat tappet cam.
On a similair subject; is there any value in running a larger diameter pushrod in a street/strip application or are the larger diameter pushrods for hardcore strip engines?
Any help greatly appreciated.

Regards,
Martyn

 

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Any time parts in the valvetrain are changed, you need to check the geometrey.
I've seen quite a variaton between different brands of roller rockers. Base circle vary with the size and type of cam. Aftrmarket heads can change things drastically. Last Windsor I built(425ci) used Victor Jr heads and a solid roller- wound up with a 8.400 push rod-- which is probably 1/4 inch longer than stock.

Push rod size and wall thickness will depend on spring pressure and RPMs . 5/16 can be used in most mild and moderate builds.
 

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Just for reference AFR's website has the ultimate cylinder head guide in their articles section. Part 6 was a 393W with several different sets of heads. They (MMFF) used 8.250 for all the inline heads including the AFR 205's, same deck thickness as the 185's. Should be ballpark but a pushrod length checker and a good machinist may be even more accurate.
 

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Forget about the stock pushrods. Use a length checker, and yes upgrade.
 

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On 2006-09-14 13:28, scottford351 wrote:
Any time parts in the valvetrain are changed, you need to check the geometrey.
I've seen quite a variaton between different brands of roller rockers. Base circle vary with the size and type of cam. Aftrmarket heads can change things drastically. Last Windsor I built(425ci) used Victor Jr heads and a solid roller- wound up with a 8.400 push rod-- which is probably 1/4 inch longer than stock.

Push rod size and wall thickness will depend on spring pressure and RPMs . 5/16 can be used in most mild and moderate builds.

was your block decked?
I have a 357 with solid roller (1.9" springs) victor jr's, crower lifters and checked to a 8.450" pushrod, close tho
 
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