Series II L67 Grand National??!!??
- Thread starter xXch0dyXx
- Start date
grossebarbe
New Member
- Joined
- Mar 11, 2013
Hello everybody. This is my first post here. I've been following this thread with great interest. I'm about to swap the 3800 of a 1999 firebird into my 1987 GN. However I want to use the GN ECM to control the series II.
I believe I will be able to reuse most of the LC2 sensors on the series II. The ones I don't know are the crank position sensor and the cam position sensor. What are the options?
Is it possible to rewire the series II cam and crank sensor into the LC2 wiring harness?
Can someone burn a PROM that will use the series II cam and crank sensors?
Is it possible to swap the vibration damper or only the crank sensor?
Did the only way to get a cam signal is to use a belt driven distributor set-up with the stock cam sensor?
Thank you.
I believe I will be able to reuse most of the LC2 sensors on the series II. The ones I don't know are the crank position sensor and the cam position sensor. What are the options?
Is it possible to rewire the series II cam and crank sensor into the LC2 wiring harness?
Can someone burn a PROM that will use the series II cam and crank sensors?
Is it possible to swap the vibration damper or only the crank sensor?
Did the only way to get a cam signal is to use a belt driven distributor set-up with the stock cam sensor?
Thank you.
I'm using the reverse, L67 ECM on an older 4.1. It's not that hard to cross the sensors actually. Pretty much everything bolts on and since the 3.8L in the FWD Century used the same ECM as the LC2 but with a flying magnet like the L67, I don't see why you couldn't wire the L67 sensor in. Mine works with the LC2 distributor stub system.
You can use the "quick start" ICM to use the L67 rings but I think you'd have to swap to the correct crank sensor for the ICM vs. using the L67. Otherwise it's pretty much much just replace the L67 sensor with the LC2 sensor or repin the harness in the cases of things like CLT and IAT. TPS will require a wiring adapter though since I don't think you physically get the LC2 TPS on the L67 throttlebody.
The IAC is an unknown, I swapped mine for the newer version but I don't know of an adapter to go the otherway. Supposidly it's functionally the same with a different pin out but someone else will have to confirm that for you.
You can use the "quick start" ICM to use the L67 rings but I think you'd have to swap to the correct crank sensor for the ICM vs. using the L67. Otherwise it's pretty much much just replace the L67 sensor with the LC2 sensor or repin the harness in the cases of things like CLT and IAT. TPS will require a wiring adapter though since I don't think you physically get the LC2 TPS on the L67 throttlebody.
The IAC is an unknown, I swapped mine for the newer version but I don't know of an adapter to go the otherway. Supposidly it's functionally the same with a different pin out but someone else will have to confirm that for you.
grossebarbe
New Member
- Joined
- Mar 11, 2013
Thank you ctx-slpr, that solve my issue. I will build an adapter plate to bolt the GN throttle body onto the series II intake. Therefore I wont have to swap TPS and IAC.
grossebarbe
New Member
- Joined
- Mar 11, 2013
Btw what's involved in the ICM swap? Is it possible to rewire the series II ICM into the LC2 wiring harness?
http://www.turbobuicks.com/forums/buick-v6-turbo-tech/57874-quick-start-installation.html and I think Turbo1dr on this board has posted it in the how to section
I have been doing a full paint correction for the past week to get the car ready for the Buick show in Norwalk this weekend. I hope to have it completed by wednesday so we can start fabbing the new 3.5" external gated DP in time for the show. It is going to be a close call. Will post some pics once I get it out of the garage. 24psi at 50% tps is a bit too much for my liking, so it wont be getting back to the dyno or track until this new DP gets fabbed.
GBGN1
stroked
- Joined
- May 26, 2001
A wealth of information, my brother and I would like to put a series 2 turbo motor in our H body hybrid. Does anyone know if the series 2 motor is narrower than the 109 motor? I know the deck height is lower which will make it a little narrower I believe, what about the heads? Does anyone have the width of the series 2 motor exhaust flange to exhaust flange compared to same on the 109 motor? We desperately need the space for exhaust manifolds and down pipe.
thank you
thank you
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
I think I can help you with that info. Measuring the distance from the outside of one cylinder head to the other at the top of the exhaust ports, Series 2 and Series 3 motors have a width of about 17 3/4" which you will find to be significantly narrower than the 109 motors, 3.8 FWD motors, and 3800 Series 1 motors.
That seems nice and narrow, Now if I could only find the same width for the old motor, I would have a concrete idea what I will be dealing with. I searched and saw a width of 26, but that seems too wide, maybe it includs manifolds. I cannot believe the new motor is 8 inches narrower. I could believe 4, but 8 seems crazy.
RunninShine231
Member
- Joined
- Feb 17, 2013
excellent thread am surpried we arent lining up to do this swap. can only imagine driveability improvements, she must be a diffrent animal.. WE ARE ALL WAITING TO SEE YOU TURN IT UP
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
The Series 2/3 engines are superior in many ways compared to the 3.8 and even 3800 Series 1 engines. The heads flow better, the blocks are stronger, etc. But I think why you are NOT seeing people line up to do this swap is because the stock GN transmission cannot be used (without and expensive adapter plate) and a lot of custom parts and wiring work are needed to put it in a G-body. But to me, the performance gains are worth it and I would rather have an electronically controlled 4L60-E than a governor controlled transmission any day of the week and twice on Sunday. But a lot of guys we talk to who are interested in 3800 GN swaps are disappointed to find out many of their performance mods and custom 2004R builds they already bought and paid for won't work with the 3800. And I think that's where the big hang-up is right now.
I have an ambitious plan for my future GN purchase and build. I'm thinking C5/C6 Corvette front and rear suspension + torque tube (to take the twisting forces out of the body and frame), 4L80-E transmission mounted directly to the Corvette rear end, and custom 3800 Series 2/3 build with a modern turbo. The back seat of my future GN will probably have to go in favor of dual bucket seats to clear the transmission tunnel.
If I so choose, I could also install the active handling and ABS systems from the donor Corvette.
-ryan
I have an ambitious plan for my future GN purchase and build. I'm thinking C5/C6 Corvette front and rear suspension + torque tube (to take the twisting forces out of the body and frame), 4L80-E transmission mounted directly to the Corvette rear end, and custom 3800 Series 2/3 build with a modern turbo. The back seat of my future GN will probably have to go in favor of dual bucket seats to clear the transmission tunnel.
If I so choose, I could also install the active handling and ABS systems from the donor Corvette.
-ryan
