Cascade Crew

Alphius · Posted: Tue Mar 12, 2013 8:12 pm Post subject:

Now that the alternator isn't making terrible noises I can hear the piston slap that my engine apparently has. Sad

Oil pressure is fine and it goes away when it is up to temp, classic LS engine piston slap.

http://youtu.be/Nzj-QMkDIQQ

Twilightoptics · Posted: Tue Mar 12, 2013 8:23 pm Post subject:

Get some good oil in there and drive it.

Alphius · Posted: Tue Mar 12, 2013 8:27 pm Post subject:

I have fresh Rotella T6 in it right now and a Wix filter.

I will get the rest of what needs doing, done, and then drive the wheels off of it. Smile

Stupid dang heatercore replacement
Interior reassembly
Ball joint
Alignment

By the way Paul, you will be glad to know the y-pipe appears to be leak-free. Very Happy

Twilightoptics · Posted: Tue Mar 12, 2013 8:28 pm Post subject:

I forgot about the slap issue myself till I read your post lol.

aaron_sK · Posted: Tue Mar 12, 2013 8:29 pm Post subject:

*Edit: ninja'd Razz

I'm with Paul. The T6 is about as good as your gonna do unless you want to go with a 15w40 and that seems like a bad idea for an LSx.

Twilightoptics · Posted: Tue Mar 12, 2013 8:37 pm Post subject:

Tolerances aren't any tighter than a normal SBC, thick oil might do the trick. Maybe some Castrol 20w50 lol

Alphius · Posted: Tue Mar 12, 2013 8:52 pm Post subject:

Honestly, as long as it goes away when warm I think I will stay with T6. I'm not too worried about it. Tons of people have some slap with these motors, mine isn't any different. I'm gonna see if my dad's '99 does it too when I go visit them this weekend. Wink

He runs T6 too.
Thank you GM. #$%^&*

Loose motors make more power, right? Rolling Eyes

chevymad · Posted: Tue Mar 12, 2013 9:09 pm Post subject:

Only loose when they're cold..

Twilightoptics · Posted: Tue Mar 12, 2013 9:16 pm Post subject:

That doesn't make sense at all. Blowby is wasted power.

Alphius · Posted: Tue Mar 12, 2013 9:19 pm Post subject:

I know guys, I was trying to convey some sarcasm there. Very Happy

I saw like 5 people in different threads on LS1Tech saying that if it has piston slap it will make more power. Laughing

Mine's not as bad as a lot of examples I found so I am just gonna go with it like I said before and not worry.

Twilightoptics · Posted: Tue Mar 12, 2013 9:26 pm Post subject:

My jeep has nasty lifter tap every 10th time it starts up for a few seconds.

Good oil makes it okay :O)

hnkajnk · New Member Joined: 30 May 2011 Posts: 10

Yes, The Z28 has some "slap" when it's cold. I was kinda worried about it.. Shocked

So this is normal?

chevymad · Posted: Wed Mar 13, 2013 6:54 pm Post subject:

GM said if you didn't find too much iron on the magnetic drain plug then there was nothing to worry bout. Basically the pistons are loose when the engine is cold then expand to fill the cylinder.

Did gm use forged pistons? Forgings were famous for this. Especially the old TRW ones because they started out oval and then rounded out as they warmed up.

fiveoformula · Posted: Wed Mar 13, 2013 8:35 pm Post subject:

I always wondered what the rhyme or reason for the noise was... changing oil at chevy, I've heard enough of them start up, some ticked a little, some ticked a lot, some just turn over cold and don't make a sound.

Alphius · Posted: Wed Mar 13, 2013 8:46 pm Post subject:

The LS1 pistons are not forged. They are hypereutectic aluminum.

The short skirt piston design in the LS1 is more susceptible to piston slap than older Chevy engines. There's also talk that quality control wasn't too great on what size pistons that are "in spec" went into what bores that were also "in spec" but left enough clearance for the short skirt piston to knock around a little when it is cold. Basically, GM says it's normal as long as it goes away when the engine warms up.

Tons of the GenIII engines rattle a bit when cold. No big deal.

83Z28BlackBetty · Posted: Thu Mar 14, 2013 9:40 am Post subject:

Dude that's freaking Badass! I'm glad you got it all sorted out. I can't wait to see it in person. Good work man, that's something to be proud of for sure.

-JAKE

Alphius · Posted: Fri Mar 15, 2013 10:28 am Post subject:

I drove around a bit last night. Runs good.
Steam line is leaking a bit of coolant at the head crossover, I will fix that up soon so I can start driving it every day. Smile

This makes me want to do a swap in my truck too. The carb 350 just doesn't compare to the LS1! Very Happy

fiveoformula · Posted: Fri Mar 15, 2013 11:16 am Post subject:

Sick! Get a nice 5.3 or 6.0 in the truck too!

Alphius · Posted: Fri Mar 15, 2013 11:59 am Post subject:

Yeah, I am thinking a 5.3/4L60E 2WD dropout would go in pretty easily and cheaply.
I might not be able to resist the temptation. Wink

Alphius · Posted: Fri Mar 15, 2013 5:47 pm Post subject:

My new air filter. Airaid SynthaMax non-oiled filter. HotWheels for size comparison. Very Happy