Old LS1 ailing, time for a change.

[A_Harman]

Let's all have a moment of silence for the LS1 in my 2002 Camaro:
254000 miles
14 years of track days
estimate 180 hours of accumulated track time
It has been a trusty steed for all these years, but high oil consumption and high rpm knock has made me buy a new horse. Just bought an LS3 out of a C6 Corvette with 30k miles on it. I think I got a fairly good deal on it because it is coming with the ECU, wiring harness, and all the accessories still attached.

My only definite plan so far is to put a Lingenfelter GT1 cam in it before installation.

So all you LS gurus out there, clinebarger, dailydriver, etc., I need some input.

Would it be easier to keep the OE LS1 harness and ECU, or should I use the LS3 electrics?
The Lingenfelter 58x-24x adapter box is reasonable cost ($255), and I can get a cable-actuated throttle from Summit ($330 for a BBK, more for others).


What kind of issues would I run into if I use the LS3 ECU and harness? Are there gauge issues that could occur?

I'm debating about headers in this buildup. I want to keep the car as a daily driver, and my opinion is that when headers are installed, a line has been crossed making the car less reliable.

 

[austinlunsford]

I don't know much about GM LS engines, but I'm not sure how headers would make the car less reliable, unless they will scrape the ground, or you are worried about exhaust leaks? If you do get them, you know as well as I do, now is the time to put them on while the new motor is out.

 

[SteveSRT8]

Get good quality headers and coat them. Keeps the under hood temps down and protects against rust.

I had headers on a project truck for almost a decade and never heard a peep out of them. Your cam will love you for it.

RIP LS1...

 

[DriveHard]

I have had headers on my daily driver truck for almost 4 years now...never a problem.

 

[mazdamonky]

Headers are a reliability issue? (this is a serious inquiry) I have headers on all 3 of my cars. the only minor issue I had on any of them was an exhaust leak on the 302. Just replaced the gasket and put a new bolt where there was one missing and it was fixed. The only reason I could imagine them being an issue is road salt eating through an inferior quality metal. If you are using a name brand with stainless steel, there should be no issues.

 

[DriveHard]

oh yeah...I had headers on my daily driver Nissan Sentra SER Spec-V for 5 years without an issue as well.
about the only thing you will notice besides the increase in power and torque is some additional noise. Louder exhaust as well as a distinctive noise from under the hood.

 

[DoubleWasp]

I'm also a little lost on how headers are a reliability issue and make a car not a daily driver.

Key is to get good quality headers that are stainless, coated, or both, and with good bends so as not to be an issue for clearance.

If you're set on doing a cam, headers will be no less a detriment, and quite the complement to the cam.

 

[ARCOgraphite]

I see and e-throttle pedal and kit is available, as well as hot rod harnesses.

Why a lingenfelter cam? Sounds expensive - though I bet its got some good dyno time on it. Metallurgy nitriding consistent and better? I would guess one of the big grinders make this for him as a spec part contract.

 

[dareo]

From my limited understanding, in order for everything in the car to work right,(stock gauges) you use the original harness and reprogram the ECU to run an LS3, and the reluctor wheel converter or a wheel swap.

I am interested in the LS3 upgrade as well for my truck, just for fun, stock engine still doing great.

I haven't seen compelling cases for headers unless you really need that very small improvement of power. The GM cast manifolds actually do pretty well.

 

[clinebarger]

The Speedometer, Temp Gauge, & Fuel Gauge will be the biggest hurdles.

The (LS3) E38 ECM does not have a 4000 pulse per mile signal that the Speedo needs, It has a 128,000 PPM signal, You can divide the signal down from 128K to 4000 using a binary counter IC, voltage regulator, 100uF capacitor & a prototype board to solder them to. Cost under $10 in parts. (EDIT....A 2008 Corvette has a dedicated VSS Output too the Cluster/Heads-Up) This MAY BE a 4000PPM signal??)

The Oil Pressure is easy, The sender is wired directly to the Cluster, A Tach signal is easy enough.

On your Camaro the Temp & Fuel gauges get there signals through a Class 2 Serial Data line from the PCM. Unfortunately, A E38 ECM has NO Class 2 Serial data line.......They have a GMLAN "High Speed" Serial Data Lines.
Their are several Class 2 Modules on a '08 Corvette including the instrument cluster. However Class 2 & GMLAN Modules do not communicate directly with each other thus the need for a "Gateway Module"....."The interaction between high speed GMLAN and class 2 is assured by BCM, which is the gateway. Any message to or from the class 2 modules to the high speed GMLAN modules is translated by the BCM"

'08 Corvette Cluster Diagram....

'02 Camaro Cluster...

 

[artificialist]

The LS3 has a valve timing phaser and the LS1 doesn't. Either the LS3 wiring harness would need to be used, or perhaps the valve timing phaser can by removed. Does this Lingenfelter cam do something about the valve timing phaser?

As for problems related to headers, I am not sure if having headers automatically means less reliability. Some cars left the factory with exhaust manifolds that basically resembled headers and it was never a problem. The one problem I have heard is that headers might radiate more heat into the engine bay, and that might be enough heat to shorten the life of various components.

Some people have made a compromise. Rather than keep the iron manifolds or get headers, they have their factory iron manifolds ported and coated with ceramic.

 

[clinebarger]

Option 1. So for the E38 too run the Temp & Fuel gauge, You will at least need a BCM as a Gateway. The Communication Protocol it most likely the same.....But I CANNOT GUARANTEE this to be fact!!!!

Option 2. Keep your current "P01" PCM just for the Gauges, And run the E38 ECM for the Engine.
Cull the harness of all engine function wires & leave Powers, Grounds, ECT circuits, Fuel Level Inputs & Serial Data. Put your LS1 ECT sensor in the right cylinder head. The ECT in the left cylinder head will give input to the E38 ECM, The E38 will provide Tach & Speedo functions, The Oil Pressure Sensor will stay wired to the Body Harness. I guarantee this can be made to function.....But it will be quite a bit of work on your end. I can walk you through it.

Option 3. The Lingenfelter 58x-24x Box, They seem to be quite reliable. But....You need to look over your engine harness, It could be in pretty bad shape at 250,000 miles. Look for splits in the insulation at termination points....TPS/IAC/ECT/MAF etc.
The 3 1/2" LS1 MAF is too small for a LS3, Have it "Speed Density" Tuned if you stay with Gen III electronics & ditch the MAF all together.

Option 4. Tear the engine down & install a 24X crank reluctor & 3-bolt 1X timing gear & Cam, As you know that is what I'm doing......BUT I have a brand new harness on my Gen III engine.


****A C6 Vette Engine Harness will not fit your car very well AT ALL****


Bill @ BP Automotive can build you a "Plug & Play" for all options except #1. He owns a 4th Gen also! BP Automotive


Do you want Air Conditioning? Do you have ASR? What year Vette did your engine come out of?

 

[clinebarger]

Originally Posted By: artificialist
The LS3 has a valve timing phaser and the LS1 doesn't.


LS3's DO NOT have VVT, It is the only N/A 6.2L that doesn't.

 

[A_Harman]

Originally Posted By: ARCOgraphite

Why a lingenfelter cam? Sounds expensive - though I bet its got some good dyno time on it. Metallurgy nitriding consistent and better? I would guess one of the big grinders make this for him as a spec part contract.


The Lingenfelter cam is about the same cost as everybody else's. It's got nearly the same duration specs as the GM Hot Cam, but with higher lift. Lingenfelter's state on their website that Comp Cams makes all their cams.

 

[ARCOgraphite]

spounds good. I have used GM stock performance or Lunati short track cams on the street. Never got to intall a roller for a street car; its the way to go for fattest torque curve.

 

[ls1mike]

Originally Posted By: clinebarger
Option 1. So for the E38 too run the Temp & Fuel gauge, You will at least need a BCM as a Gateway. The Communication Protocol it most likely the same.....But I CANNOT GUARANTEE this to be fact!!!!

Option 2. Keep your current "P01" PCM just for the Gauges, And run the E38 ECM for the Engine.
Cull the harness of all engine function wires & leave Powers, Grounds, ECT circuits, Fuel Level Inputs & Serial Data. Put your LS1 ECT sensor in the right cylinder head. The ECT in the left cylinder head will give input to the E38 ECM, The E38 will provide Tach & Speedo functions, The Oil Pressure Sensor will stay wired to the Body Harness. I guarantee this can be made to function.....But it will be quite a bit of work on your end. I can walk you through it.

Option 3. The Lingenfelter 58x-24x Box, They seem to be quite reliable. But....You need to look over your engine harness, It could be in pretty bad shape at 250,000 miles. Look for splits in the insulation at termination points....TPS/IAC/ECT/MAF etc.
The 3 1/2" LS1 MAF is too small for a LS3, Have it "Speed Density" Tuned if you stay with Gen III electronics & ditch the MAF all together.

Option 4. Tear the engine down & install a 24X crank reluctor & 3-bolt 1X timing gear & Cam, As you know that is what I'm doing......BUT I have a brand new harness on my Gen III engine.


****A C6 Vette Engine Harness will not fit your car very well AT ALL****


Bill @ BP Automotive can build you a "Plug & Play" for all options except #1. He owns a 4th Gen also! BP Automotive


Do you want Air Conditioning? Do you have ASR? What year Vette did your engine come out of?

I like option 3, but like cline says your harness is old maybe pick up a newer LS1 harness?
I also like option 4. Trying to get the Corvette harness to work will be a labor of love.
Of course my favorite is plug and play...Saves headaches and time.