Swapping in LS3...need help!

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Sep 7, 2011 | 03:57 PM

98_TA_EMLC

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Launching!

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From: N. Va

Swapping in LS3...need help!

Ok guys, I've been searching for a while but I'm not getting a solid answer.

Most people I see in my search are using LS3 longblocks with 54x reluctor wheels whereas I am getting a LS3 shortblock with a 24x reluctor wheel and reusing my 5.3L heads, LS6 intake, etc... I'm going to be reusing as many parts as possible off my LS1.

So that said. If someone could help me narrow down exactly what parts are needed for the swap I'd GREATLY appreciate it! I'll start with my questionable items.

#1. Cam Sprocket/Timing Cover
My question about it: People are talking about the cam sensor being in a different position on the LS3 than the LS1 and requiring a LS2 timing cover with a LS2 sprocket and extending the sensor wiring...is this correct?)

#2. Valley Cover/Knock Sensors
Will my LS1 valley cover and knock sensors with stock wiring work? I'm seeing I need a LS2/3 valley cover and mention of drilling and tapping for knock sensors to screw into....where am I drilling??? I'm also seeing they say a harness is extension is needed....can I just extend the wires and solder back together?

#3. Lifters
I'm seeing pn 12499225 as what's needed for lifters....which show they're good on LS1's. So can't I just use my old LS1 lifters and a LS2/3 lifter tray???

Am I missing anything else? Since I'm using 5.3L heads and LS6 intake, I can still use LS1 fuel components right??? Just gonna need bigger injectors of course.

(I'm helping a buddy do the swap, but to make reading this easier I referred to it as if I'm doing it)

Sep 7, 2011 | 05:02 PM

01badz28

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From: Knoxville, TN

My brain is a little rusty, but I'll try to help. My L92 / LS3 swap has been running for about two year now.

[QUOTE=98_TA_EMLC;15362305]Ok guys, I've been searching for a while but I'm not getting a solid answer.

Most people I see in my search are using LS3 longblocks with 54x reluctor wheels whereas I am getting a LS3 shortblock with a 24x reluctor wheel and reusing my 5.3L heads, LS6 intake, etc... I'm going to be reusing as many parts as possible off my LS1.

So that said. If someone could help me narrow down exactly what parts are needed for the swap I'd GREATLY appreciate it! I'll start with my questionable items.

Quote:

Originally Posted by 98_TA_EMLC

#1. Cam Sprocket/Timing Cover
My question about it: People are talking about the cam sensor being in a different position on the LS3 than the LS1 and requiring a LS2 timing cover with a LS2 sprocket and extending the sensor wiring...is this correct?)

The cam sensor is in a different location - you will need an extension harness. I'm using the stock LS3 timing sprocket.

Quote:

Originally Posted by 98_TA_EMLC

#2. Valley Cover/Knock Sensors
Will my LS1 valley cover and knock sensors with stock wiring work? I'm seeing I need a LS2/3 valley cover and mention of drilling and tapping for knock sensors to screw into....where am I drilling??? I'm also seeing they say a harness is extension is needed....can I just extend the wires and solder back together?

The knock sensors will work with an extension harness - on mine the knock sensors screw into the block. Real close on header clearance, but it works.

I used the LS3 valley cover, no problem.

Quote:

Originally Posted by 98_TA_EMLC

#3. Lifters
I'm seeing pn 12499225 as what's needed for lifters....which show they're good on LS1's. So can't I just use my old LS1 lifters and a LS2/3 lifter tray???

No clue. My stock LS1 was blown to **** so I went with new LS3 lifters.

Quote:

Originally Posted by 98_TA_EMLC

Am I missing anything else? Since I'm using 5.3L heads and LS6 intake, I can still use LS1 fuel components right??? Just gonna need bigger injectors of course.

You should be good to go. The only reason you should get into using a new fuel rail is if you go with an LS2/3 style intake.

Quote:

Originally Posted by 98_TA_EMLC

(I'm helping a buddy do the swap, but to make reading this easier I referred to it as if I'm doing it)

Tell your buddy good luck. The 6.2 is a fun motor.

Sep 8, 2011 | 08:52 AM

98_TA_EMLC

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Launching!

Joined: Jan 2010

Posts: 283

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From: N. Va

Thanks for helping me with that line by line man...I appreciate it!

So it's looking like I'm gonna need cam sprocket, timing cover, cam sensor extension harness, knock sensor extension harness, and LS3 valley cover. That's not too bad!

BTW..I'm a fellow autox'er and took a look at your fquick pics....
I LOVE THIS ONE!!!!

Sep 8, 2011 | 12:31 PM

01badz28

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From: Knoxville, TN

Quote:

Originally Posted by 98_TA_EMLC

That sounds about right. I called Lingenfelter and told them what I was doing, and they shipped me a bunch of stock take off LS3 parts for fairly cheap (along with one of their reluctor wheel converter boxes).

Yeah, I figured you were a fellow cone junkie. That was taken at 411 Speedway - two wheels off into wet grass = 180! They ripped up the pavement for dirt a few years ago, which was a shame because that was a great place to autocross.

Sep 8, 2011 | 02:05 PM

98_TA_EMLC

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Launching!

Joined: Jan 2010

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From: N. Va

So here's my parts list...am I missing anything?

GM LS3 Valley Cover
28-12599296
$116.99

Knock Sensor Relocation Harness LS1>LS1
LS2-KSRH
$22.50

Cam Sensor Adapter Harness
LS2-CSAH-2
$19

2x Cam Sprocket
12576407
$32.18

LS2 Timing Cover
12596023 or 12600325
$78.18

Cam Chain Damper
12588670
$11.56

VICTOR REINZ LS3 Cylinder Head Gasket
54660
$25.99 each

GM Gen IV Cylinder Head Bolt Kit
28-17800568
$61.99 each

GM LSX Water Pump Gasket Set
28-12630223
$8.99

Sep 8, 2011 | 02:07 PM

98_TA_EMLC

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Launching!

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From: N. Va

Yeah I would've enjoyed racing there myself. Everything we do around here is flat surfaced pavement...banks make for more speed = more fun with entry and exit points

Sep 8, 2011 | 03:56 PM

01badz28

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From: Knoxville, TN

Quote:

Originally Posted by 98_TA_EMLC

Looks good. Not sure about the head bolts since it sounds like you are using LS6 heads - mine is using L92/LS3 heads. Might as well do a new timing chain while you are in there - my C5R has held up well.

Quote:

Originally Posted by 98_TA_EMLC

Yeah I would've enjoyed racing there myself. Everything we do around here is flat surfaced pavement...banks make for more speed = more fun with entry and exit points

I was hitting high 80s there with the stock LS1 - would love to see what she would do now.

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