Ls3 piston help! - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

1968firebirdls3 · 08-06-2016, 03:42 PM

Hey guys, I had a local engine shop assemble my rotating assembly. I picked it up yesterday and noticed one of the Pistons was facing the wrong way but all the valve relives lined up and looked identical to the next. There is one on each side like this. Is this okay? Will it work? Hurt anything? Please help guys.

1968firebirdls3 · 08-06-2016, 05:27 PM

Anybody?

15rs/ss · 08-06-2016, 05:39 PM

can be answered by only one person.

15rs/ss · 08-06-2016, 05:44 PM

I think it looks somewhat dirty. IM NOT AN ENGINE BUILDER. Someday maybe

1968firebirdls3 · 08-06-2016, 05:48 PM

Thinking the same thing. Considering it's all new parts. Just want to make sure I get enough information so I don't look like a dumbass taking the engine back.

CFD · 08-06-2016, 06:43 PM

Someone wasn't paying attention.

Rcheli4fun · 08-06-2016, 07:09 PM

The arrows are on there for a reason i think the skirts have something to do with it
I would take it back and have it changed no use in taking any chances

1968firebirdls3 · 08-06-2016, 07:44 PM

Yea you guys are right, got In touch with my engine builder and he's gonna fix me up Monday morning. Best to play it safe.

christianchevell · 08-06-2016, 10:12 PM

Did you have it align honed? I am not seeing any cross hatch pattern to the cylinder sleeves, and it looks dirty and oily needs a good cleaning on top of the piston issue. I would dry it with a clean shop rag and spray it with cleaner and also air clean it good before assembling any gaskets on that. Being that our cylinder heads are exactly the same on each side and the pistons may have the top concentric and perfectly split down the center with the valve reliefs perfectly the same in depth it may not have done anything...... Then again with the angle of the valves from the heads ..it appears placed right for even being on the wrong side as far as the reliefs are yet I do not know if the piston has to face front due to skirt or connecting rod or......whatever..... its always better safe than sorry ,Good luck.

1968firebirdls3 · 08-06-2016, 10:45 PM

I did have it aligned honed. There's a lot of cross hair hatches, it's just a poor
Showing. I had it aligned honed with arp main studs

Bo White · 08-07-2016, 09:00 AM

Align hone is a machining process for the mains.

Bo White · 08-07-2016, 09:02 AM

Reason there are arrows on the piston is in case there are offsets machined in the wrist pin hole.

1968firebirdls3 · 08-07-2016, 04:25 PM

I don't think my Pistons have offset machined pins. Will I be okay like that?

CFD · 08-07-2016, 04:45 PM

Most modern day piston design utilize offset pins including LS motors. There are other design factors that could determine direction, you should have them installed correctly without doubt. By the way, they look like Weisco pistons, if so, they are offset.

08-06-2016, 03:42 PM	#1
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	Ls3 piston help! Hey guys, I had a local engine shop assemble my rotating assembly. I picked it up yesterday and noticed one of the Pistons was facing the wrong way but all the valve relives lined up and looked identical to the next. There is one on each side like this. Is this okay? Will it work? Hurt anything? Please help guys. Attached Images

08-06-2016, 10:12 PM	#9
christianchevell old school chevy rodder Drives: 2013 2SS/RS Manual,DM exhaust,CRT Join Date: Jul 2012 Location: Oregon Posts: 5,588 View My Garage	Did you have it align honed? I am not seeing any cross hatch pattern to the cylinder sleeves, and it looks dirty and oily needs a good cleaning on top of the piston issue. I would dry it with a clean shop rag and spray it with cleaner and also air clean it good before assembling any gaskets on that. Being that our cylinder heads are exactly the same on each side and the pistons may have the top concentric and perfectly split down the center with the valve reliefs perfectly the same in depth it may not have done anything...... Then again with the angle of the valves from the heads ..it appears placed right for even being on the wrong side as far as the reliefs are yet I do not know if the piston has to face front due to skirt or connecting rod or......whatever..... its always better safe than sorry ,Good luck. __________________ 2021 Wild Cherry ZL1 A10, Sunroof, Data, Carbon, Nav, RotoFab Dry CAI, Elite x2, Borla ATK, Driveshaft shop

08-07-2016, 09:00 AM	#11
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,018	Align hone is a machining process for the mains. __________________ Retired wanna be cylinder head porter 2015 2SS 1LE Clutch reservoir, Vararam DRX, ported TB, TSP 2" headers, MGW shifter Totalled: 2010 1SS Wilkes Performance/Eagle 416 shortblock, TSP custom valvetrain, PRC 260 heads, Edelbrock Pro Flo 102, th400 swap, 8" PTC 5500 stall= 535/435 at the wheels tuned Gen 3 Performance and Dyno 10.97 @ 124 full weight in 3100 DA CamaroFest X

08-07-2016, 09:02 AM	#12
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,018	Reason there are arrows on the piston is in case there are offsets machined in the wrist pin hole. __________________ Retired wanna be cylinder head porter 2015 2SS 1LE Clutch reservoir, Vararam DRX, ported TB, TSP 2" headers, MGW shifter Totalled: 2010 1SS Wilkes Performance/Eagle 416 shortblock, TSP custom valvetrain, PRC 260 heads, Edelbrock Pro Flo 102, th400 swap, 8" PTC 5500 stall= 535/435 at the wheels tuned Gen 3 Performance and Dyno 10.97 @ 124 full weight in 3100 DA CamaroFest X

08-07-2016, 04:45 PM	#14
CFD Drives: 2SS/RS L99 BLACK Join Date: Apr 2010 Location: Franklin , MA Posts: 6,696	Most modern day piston design utilize offset pins including LS motors. There are other design factors that could determine direction, you should have them installed correctly without doubt. By the way, they look like Weisco pistons, if so, they are offset. Last edited by CFD; 08-07-2016 at 05:08 PM.

08-06-2016, 05:27 PM	#2
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	Anybody?

08-06-2016, 05:39 PM	#3
15rs/ss Drives: 2015 Yellow 2SS LT Z28 cai tune Join Date: Aug 2015 Location: Tallmadge,Ohio Posts: 208	can be answered by only one person.

08-06-2016, 05:44 PM	#4
15rs/ss Drives: 2015 Yellow 2SS LT Z28 cai tune Join Date: Aug 2015 Location: Tallmadge,Ohio Posts: 208	I think it looks somewhat dirty. IM NOT AN ENGINE BUILDER. Someday maybe

08-06-2016, 05:48 PM	#5
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	Thinking the same thing. Considering it's all new parts. Just want to make sure I get enough information so I don't look like a dumbass taking the engine back.

08-06-2016, 06:43 PM	#6
CFD Drives: 2SS/RS L99 BLACK Join Date: Apr 2010 Location: Franklin , MA Posts: 6,696	Someone wasn't paying attention.

08-06-2016, 07:09 PM	#7
Rcheli4fun Drives: 2011 camaro 2SS RS Join Date: Apr 2014 Location: Iowa Posts: 75	The arrows are on there for a reason i think the skirts have something to do with it I would take it back and have it changed no use in taking any chances

08-06-2016, 07:44 PM	#8
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	Yea you guys are right, got In touch with my engine builder and he's gonna fix me up Monday morning. Best to play it safe.

08-06-2016, 10:45 PM	#10
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	I did have it aligned honed. There's a lot of cross hair hatches, it's just a poor Showing. I had it aligned honed with arp main studs

08-07-2016, 04:25 PM	#13
1968firebirdls3 Drives: 1968 firebird Join Date: Jul 2016 Location: Baton Rouge Posts: 48	I don't think my Pistons have offset machined pins. Will I be okay like that?