01ssreda4

iTrader: (96)

For the most part LS heads are very good quality, you find that most (even higher mileage units) do not require a valve job. If you are swapping on a used set, and want to save some $$$ at the machine shop, here is an alternative for you. I hope this gives you an understanding of valve sealing, and saves you some money.

These heads were taken to a machine shop. They were cleaned and milled lightly but no other work was performed. The bill was around $80.



Here's an intake valve. Notice the silver streak around the lower edge. That's where it seals to the valve seat in the head. We are gonna freshen that surface and hopefully widen it some for a better seal.



Take your compound, and spread it like so. Doesn't have to be perfect.



Stick it into its hole and clamp your drill onto the stem so you can use the drill to spin the valve in the head.



Use the slow speed setting on your drill, and move it in and out (on and off the seat). Wow what a difference 20 seconds makes.



Comparison.



The sealing surface in the head.



Exhaust valve comparison. A little pitting on them is normal and nothing to worry about. Once i mate a valve to a hole, it stays there. I dont move it around once its been ground in. Also make sure you wipe as much of the compound off the head and valve as you can when youre done and hit the valve stem with some wd40 to help it slide in the valve guide easier.



Thats it, repeat the procedure for all 16 valves, makes sure you have a nice even band around each valve and you're good. If one looks off or not even all the way around check the valve and see if its bent slightly. Any questions just ask.

StealthFormula

iTrader: (35)

Great write up, easy to follow, thanks for putting this together!

nine8ss

iTrader: (5)

Good stuff man. Thank you

G Atsma

Another potential sticky in the making....

OLDWS6

A friend of mine uses a similar technique but he attaches a 10 inch or so section of rubber tubing to the valve stem to avoid side loading the valve guides.

01ssreda4

iTrader: (96)

6k rpms redlines, non-roller rockers......that drill aint doing nothing to that valve guide.

RonSSNova

iTrader: (3)

And I thought I invented this.......I do it exactly the same.
I use motor oil on the valve stem/guide.

Ron

Modchevelle

iTrader: (9)

I agree with Ron..same here.

Stampede4ever

Do you reverse the direction of the drill? I do it buy hand, with back and forth motion.

Thanks.

01ssreda4

iTrader: (96)

I just go one direction, reversing it wouldnt hurt a thing.

LS1MCSS

iTrader: (18)

Me too. Been doing that for years.

moekluse

iTrader: (2)

I wish I saw this yesterday, i sent my heads to the machine shop!

vettenuts

iTrader: (4)

Done it on every set of heads I have apart (even new out of the box) but I do the old fashioned wooden stick with a rubber suction cup on the end.

Biggest snag for a first timer is to make sure you get all of the lapping compound off the head and the valve.

AnotherWs6

iTrader: (17)

Great info, easy at home stuff for the low budget projects. Heck, even has a Ryobi drill, super budget friendly, lol!

A.R. Shale Targa

iTrader: (2)

Old school method here as well..............
Great info 01ssreda4

01ssreda4

iTrader: (96)

I got the ryobi as one of their $100 HD combo specials. The impact driver is ****, the drill, mediocre at best.

CR500

I'm also an old-schooler and do it by hand with the stem / guide oiled.

Dian

frankly, its the first time i see somebody grab the valve by the stem. the procedure i know is to put a suction cup on the valve face and press on it.

01ssreda4

iTrader: (96)

I started doing it that way, nothing wrong with it, it just takes forever. Quick blip with the drill and youre done. Thats why i do it that way.

Dian

well, suction cup is in a drill of course.