MagiC5

So i'm curious is there a way to reduce the sewing machine sound under my hood???

I have a 98 C5 with a 228R cam, LT's , LS6 intake, Z06 ti's, UD pulley Stock head/block, harden push rod (stock length) LS6 oil pump,


I have oil pressure... sometime enough to make me nervous about blowing the sensor..

I turn my car off at most drive ups, (bank, mcd etc) because they can't hear me over the car.. and dont' get me wrong i love the sound of my car... but at the sametime if i could reduce the the noise under the hood by upgrading some internals i'm all ears...

ws.6kid

use a thicker oil.

Cobra4B

iTrader: (9)

Most all LSX motors have that sewing machine noise... more aggressive valve-train/cam only enhances it.

Apparently there's a new caddy racing lifter that is a direct replacement and is prooving to really quiet things down.

SHINER

iTrader: (18)

are you sure you put in the correct length pushrods?

MagiC5

Running 10w right now... and i think i might look into these lifters when i swap heads in the next couple of months....


is it the heavier springs to keep up with the agressive valve train thats causing the noise or is it just the valve train it's self... I'm using far heavier springs than required for my application.

MagiC5

well i didn't measure them... but i did a side by side comparison of the new and old and are of equal length..

2000LS1TA

iTrader: (26)

I would try a thicker oil. My father uses 20 50 in his chevelle and it has a HUGE cam and there's no ticking

SHINER

iTrader: (18)

I dont think our motors like such thick oil. I would run a 10W 40 Full Synthetic.

Sewing machine sounds are normal get use to them.

you should have gotten 7.400 pushrods with a 228 cam

vettenuts

iTrader: (4)

First number only denotes pumpability at 40* C, you need to look at the viscosity number at 100*C keeping in mind that the "30" denotes a range not a value. German Castrol is very high in the 30 weight range at 11.7 Cst.

Did you measure for your pushrods? Aftermarket cams generally have a smaller base circle, and as such, to maintain the same lifter preload requires a longer pushrod. If you didn't measure you are guessing. This may be the source of the noise that you are describing that seems to be very loud and not necessary.

slow trap

iTrader: (22)

you will need a longer pushrod than stock with an xer lobe, the base circle is smaller.i didn't know that until pred informed me.the best way is ofcourse to check but you will probably need 7.425 or longer to get the proper preload.i had a set of heads milled .030 so i thought i would need 7.350 but it sounded horrible so i put my 7.4s back in and it made a world of difference,i couldn't believe how much quieter it was.i didn't check preload but the 7.35s were definitely to short.i had a 228r also.i say get you a p-rod checker and find out exactly which ones you need and that will cure alot of your problems.

MagiC5

ok now i'm really curious... Sorry i can't remember exactly what length the rods are i know they are equals of stock which i believe is 7.4???

are you saying i need longer or shorter rods?

DaddySS

In all likelihood you need longer rods. You should measure first but if you have a lot of valve train noise it's a good bet you have too little preload and need longer rods. I went from 7350s to 7400s and it made a world of difference - valve train is nice and quiet now.

SHINER

iTrader: (18)

7.4 is GM Factory pushrod length, unless told by the people that sell the cam and they recommend a diffrent length.

SStheBest

iTrader: (2)

all of u guys are forgetting rocker arms....u would be surprised how much sewing machine noise can be quieted by changin out rockers

SHINER

iTrader: (18)

nothing is wrong with the factory rocker arms(1.7). It is one of the only pieces on the LS1 that some dont wanna change. Its balanced on both sides and isnt heavy. Many aftermarket rocker arms produce valve float which isnt good for the motor and kills performance BIG TIME.

datsbad

iTrader: (3)

what rockers have roller tips that would quiet down this noise and fit under a stock valve cover ?
is there an adjustable roller rocker that could take care of a slightly short pushrod?

DONAIMIAN

iTrader: (18)

FYI stock pushrod length is like 7.38X, cant remember off the top of my head.

SHINER

iTrader: (18)

7.369476383759859373689593729999 or just 7.4, lol Dom

TWISTEDTA

The ticking will go away-Or mostly go away after the springs are broken in. Now a days mine only ticks loud when its first started, then it warms up and you can barely hear them.
When i first installed my heads, it was a different story

ws.6kid

dude.. Just get adjustable rockers and be done with it. that way you can keep your pushrods and adjust to whatever preload you want to keep the noise minimal. They are a bit pricey but convenient...