Bad Blu Formula

iTrader: (3)

I heard that to quiet down your valvetrain you can run a 7.425 pushrod. This ofcourse is if your cam isn't humongous. This probably applies to the .570-.590ish lift cams out there I would assume. Anyone see any results from running the longer pushrod as opposed to the 7.4?

DONAIMIAN

iTrader: (18)

It has nothing to do with cam size, its about accomplishing the correct preload. Since the stock rockers are non adjustable preload has to be set by either shimming the rockers (pain in the ***) or getting the right pr length (need to invest in a length checker) If your worried about it and want to get it right invest in calipers and a measuring pr that way you can get pretty close to the correct plunger depth.

740racing

iTrader: (10)

i run them, but I also have a baby cam .525/.525

sho-me speed

iTrader: (55)

Cam size means nothing. It is the base circle of the cam that determines the preload. I run them because I wanted more thanthe .040 preload that most people end up with when they use 7.4's. I measured mine with a PR length checker and the 7.425 gave me .065 preload.

Zitty'sZ

iTrader: (29)

I just fired my car up tonight after installing a set of patriot ls6 heads and their 226/226-585/585 cam along with 7.425 pushrods and HS rockers and the valve train is VERY quiet! I used the comp cams adjustable pushrod to measure the lifter preload and I also checked the swipe pattern of a few different length pushrods and the 7.425's were right on the money!

Thimble

iTrader: (2)

7.425" is what I used when I was cam-only (LG G5X4 cam). Valvetrain was dead quiet.

CamaroSS7108

Ls6 heads 7.425 TR 224 114. Valvetrain make less noise than when it was stock.

quiet_storm98

iTrader: (48)

so what about if your heads are milled?? does that make a difference in what pushrod length you should use?? for instance i have some tea 5.3 heads that are milled 0.15 so i am wondering what length of pushrod i need.

vettenuts

iTrader: (4)

If running fixed fulcrum rockers (stock, Yella Terra, Harland Sharp) pushrod length will not affect your wipe pattern, only the lifter preload. If you want to figure out the correct preload, buy a $20 adjustable pushrod and take the measurements. Its the best and most accurate way to do this. Make sure your wipe pattern is correct first, then measure for pushrod length.

KONG

iTrader: (4)

Werd. That's why I run 7.45's.

The Alchemist

iTrader: (19)

First, I'm guessing you meant to say 0.015", which is 15 thousands as opposed to 15 hundereds. So is a stock head gave you a pre-load of .050" (for example), then milling the head 0.015 would add that to the preload and yeild 0.065" preload. But by using the pushrod checker, it will take into account the difference in head gasket thickness, smaller base circle of the cam, and any milling done to the heads.

Bad Blu Formula

iTrader: (3)

So for instance in my case: stock heads, gaskets, lifters, and a TR230 with 918's. From people that have that setup, has anyone run 7.425 pushrods? Also, with a motor that has 130k, is it going to be bad for the lifters to have more load?

PREDATOR-Z

Stock lifters have up to .100 preload on stock cams so no issues.
With a TR230 7.425 is the way to go.
XE/XE-R and in between (TR lobes) like the extra .025 on cam only.

JBIRD02

iTrader: (4)

I'm also using 7.425's with my ASA cam. Valvetrain is very quiet.

Ice Knight

iTrader: (9)

Ill be running them when I do my cam swap, that is if I can ever get this stupid salvage inspection done.

01redws6ta

I installed them and still have some "sewing machine" sound...not real bad though. Mine seems to get a bit louder as the engine/oil gets warmed up.

aus1320

Bingo! Same!

stockA4

It's 2023 everybody running 7.450" now boss get with the times

G Atsma

How times have changed!
I still remember WAAAY back in the day, on a SBC you backed off the rocker arm nut until it clicked, then went down just a quarter turn.
Pump-up alleviated. NOT prevented, just put off a few more RPM.....

LS1Formulation

iTrader: (13)

Just being able to adjust the rockers with the engine running was great! I actually cut up a pair of stock valve covers to act as shields and catch the oil before it landed on my headers.