85LSXTRUCK

iTrader: (2)

What would be the quickest way to tell the LS3 from the L99 looking at them. What should i look for? Say i am looking at a block with heads with the valve covers off?

Jimbo1367

Look at the valley cover. If it's ribbed, it had DOD. If its smooth, its a LS3. You can also look at the timing cover. If the timing has a protrusion (Kinda loooks like a hockey puck and wires coming out of it ) where the cam would go, its a L99. Thats the cam phaser. If the timing covor is flat (upper half) its a LS3

1973 STEP A SIDE

iTrader: (4)

Read !!

http://gmauthority.com/blog/gm/gm-engines/l99/

85LSXTRUCK

iTrader: (2)

I know the difference
in the 2 motors but i never seen the cam phaser on the l99 . By the way i read that long time ago.

85LSXTRUCK

iTrader: (2)

Thank you, thats a good explanation. I just never seen a pic of the cam phaser or the front of the l99 so i know for sure.

85LSXTRUCK

iTrader: (2)

I am looking at a longblock to buy and just wanted to make 100% sure it was the LS3 and I am pretty certain it sure is. I dont want the L99 for the vvt. Does anyone have a pic of the L99 with the water pump off showing the cover?

blk00ss

iTrader: (66)

85LSXTRUCK

iTrader: (2)

Thanx for the picture to show the profound differences. So many people on ebay listing there motors LS3 when indeed there not from time to time. First time i seen the actual timing covers of both side by side. I was searching for a pic like that. Thanx again.

G Atsma

Hopefully you are looking at an LS3, as converting an L99 to LS3 status can be a little costly. L99's can be cheaper than LS3's but the difference is usually not enough to cover the conversion cost.

85LSXTRUCK

iTrader: (2)

Yes its the LS3 for sure. I didnt realize the timing cover was so very different. I never owned an LS with a cam phaser.

G Atsma

NICE! Take it home and feed it well!

86bucket

2 year bump using search function.

Is there a way to tell if you have a LS3 cam or l99 cam? A buddy of mine has to put a stock cam back in his 12' Vette and remove his comp cam. He picked up a cam off Ebay that was from a 10'-15' SS Camaro. We put that cam in without looking at the part # and now curious if he has the correct cam.

I think he is ok since the other cam came with a single normal style cam bolt, and the front of the cam has a single normal hole unlike the l99 front that looks different.

Thanks

01FormulaTA

iTrader: (20)

L99 is a VVT cam, LS3 cam is not. The 2nd cam journal of VVT camshafts has a provision to direct oil to the cam phaser. See pic below...NON VVT cam on the left, VVT cam on the right....L99 cam will have 3066 as first 4 numbers on the cam, LS3 will have 3063

86bucket

Thanks