My 1989 IROC LS1/4L60E swap
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Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Well I was hoping to have it smokin tires by now but am having trouble getting in with the tuner. Now headed to Jamacia so it will have to wait till we get back...
Good luck with the 6.0! I know a few in this area running S/C 6.0s and they are just flat out monsters!!!
Good luck with the 6.0! I know a few in this area running S/C 6.0s and they are just flat out monsters!!!
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Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Small update, This thing screams!! Wow what a difference! I can't believe how this thing pulls!
far as I know I only have one bug to work out. At wide open throttle, 2-3 shift doesn't happen, just bounces off the rev limiter. Not sure why yet. May need to update a spring in the valve body or lower the shift point or raise the rev limiter??? In the meantime! I am so glad I did this swap!!
far as I know I only have one bug to work out. At wide open throttle, 2-3 shift doesn't happen, just bounces off the rev limiter. Not sure why yet. May need to update a spring in the valve body or lower the shift point or raise the rev limiter??? In the meantime! I am so glad I did this swap!! Joined: Jun 2006
Posts: 576
Likes: 4
From: Gobles, Michigan
Car: 92 Ttop Z28
Engine: Cammed 6.0
Transmission: T-56
Axle/Gears: Built 10 bolt-3.90s w/ PBR discs
Re: My 1989 IROC LS1/4L60E swap
Awesome! Time to post dyno numbers and some ride-along/ fly-by vids!!!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
No dynos here yet, 6 months or so we should have one. Will try a vid! Thanks to you and all who helped with past posts and direct answers. I wouldn't have tried to do it if it weren't for tg.org!!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
I ordered one of these UltraGauges this morning. This is a cheap and effective way to have all my gauges and then some with minimal expence!!
http://www.ultra-gauge.com/ultragauge/index.htm
I thought it was cool........................!
http://www.ultra-gauge.com/ultragauge/index.htm
I thought it was cool........................!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
The #8 coil was interfering with the A/C box directly where the box edge stuck out and a screw was there that held the upper and lower housings together. I took a whizzle wheel and carefully took away material from this area untill it cleared. Cut the screw in half and used some sealer to help it stay. Not saying it wont give me trouble down the road but this is what I did. Mainly I took materrial from the lower half Not the upper.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
I havn't updated in a while, so here goes. Trans is back out. Gonna put the Transgo 4L60E-HD2 shift kit in it. Went playing the other week @ Texas World Speedway and found that the Trans wont shift 2-3 at wide open throttle. This kit should fix that and I will keep ya posted on the results. I will say it is fun to whoop up on mustangs at the track, rolling thru the traps in neutral and still winning!!







Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
1st one is me vs a 90 red Irock with bolt ons and a tune.
2nd one is me vs a supercharged Mustang.
Junior Member
Joined: May 2011
Posts: 22
Likes: 0
Car: 1990 RS and 1991 RS
Engine: LS1 and 350
Transmission: auto and manual
Re: My 1989 IROC LS1/4L60E swap
Holley LS Engine Accessory Drive bracket as well?
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
You are gonna need the two part numbers shown in the pic depending on your water pump and accessories. also a new Idler and tentioner and belt. This is just for the A/C.
Here is a link to most of them. look through the guides and charts to figure out what you will need to purchase.
http://www.summitracing.com/search/p...ey%20ls&ddsc=1
Here is a link to most of them. look through the guides and charts to figure out what you will need to purchase.
http://www.summitracing.com/search/p...ey%20ls&ddsc=1
Junior Member
Joined: May 2011
Posts: 22
Likes: 0
Car: 1990 RS and 1991 RS
Engine: LS1 and 350
Transmission: auto and manual
Re: My 1989 IROC LS1/4L60E swap
Hey ty very much i ordered both of them today, ive been searching high and low for the past 4 days for this, thanks to you and your build its answered alot my my questions and solved alot of my problems.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Glad I could be of service
. I am not sure how other people are hooking theirs up but I am trying to hook it up to where the PCM still works with it. I took the liquid line off and am having the switch area swapped out for the 98 model thread so that I can use the 98 senso/ switch. After that I will add a relay to the system and hopefully have some cold air. It is allready 99 degrees here in College Station! I have asked and looked around here for more advice on how to hook the AC electrical up correctly without much luck. I have looked at schematics till I confuse myself. Once I get my liquid line back I guess we will see if I get cold air or an electrical fire.
. I am not sure how other people are hooking theirs up but I am trying to hook it up to where the PCM still works with it. I took the liquid line off and am having the switch area swapped out for the 98 model thread so that I can use the 98 senso/ switch. After that I will add a relay to the system and hopefully have some cold air. It is allready 99 degrees here in College Station! I have asked and looked around here for more advice on how to hook the AC electrical up correctly without much luck. I have looked at schematics till I confuse myself. Once I get my liquid line back I guess we will see if I get cold air or an electrical fire. Member




Joined: Jul 2002
Posts: 255
Likes: 9
From: Humid Houston on the Texas coast
Car: '86 Z28
Engine: SDPC TPI 350
Transmission: WC T5
Axle/Gears: 3.23 posi
Re: My 1989 IROC LS1/4L60E swap
Have a look at https://www.thirdgen.org/forums/ltx-...9-5-3-t56.html in post# 35. Prolly might want to contact him and verify whether or not he got a fire and then changed the circuit.
M
M
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Thanks!!!!! I will put that photo here for reference and see if he posts up or not? Last was said he was getting married and got a raise and it looks like No updates since????????? I hope there is no foul play goin on?
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Gonna put this here so I don't forget!
http://www.1aauto.com/1A/Interior/Ch...SV00100/336513
http://www.1aauto.com/1A/Interior/Ch...SV00100/336513
Supreme Member
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Joined: Mar 2007
Posts: 1,237
Likes: 7
From: Apopka, Florida
Car: 1989 Pontiac Trans Am GTA
Engine: cammed LS1
Transmission: Monster SS 4L65E
Axle/Gears: 9 bolt posi w/ 3.70 gears
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
That is Awesome! I was wondering where to hook up the main power from the control head!!! YAY!
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iTrader: (1)
Joined: Mar 2007
Posts: 1,237
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From: Apopka, Florida
Car: 1989 Pontiac Trans Am GTA
Engine: cammed LS1
Transmission: Monster SS 4L65E
Axle/Gears: 9 bolt posi w/ 3.70 gears
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
I do need to ask another question. If I were gonna cut the factory coils (need to come down about a 1/4 inch) would I cut off from the top of the spring or the bottom??? The bottom looks to be the the Ideal place unless someone says different?? Thanks in advance!
Joined: Oct 2005
Posts: 652
Likes: 0
From: Crestview, Florida
Car: 86 IROC-Z, 98 Z28
Engine: 370 LSx, LS1
Transmission: T56's
Axle/Gears: 3.73, 3.42
Re: My 1989 IROC LS1/4L60E swap
Nevermind, what 25th said.
Last edited by Rich92 RS; Jun 18, 2013 at 07:24 PM.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Thanks Guys! That worked fine. I havn't updated it a bit so here goes. Got my LS1 "Big Brake" upgrade done along with new struts, strut mounts and steel braided lines and got the a half coil cut off the front springs. Will wirk on getting the B&M console shifter in next and 4L60E-HD2 shift kit done. After that an alignment and hope to get the A/C working.






Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Still waiting to get shift kit installed so I went ahead and got my super cooler installed, That took 3 days. Geesh! Got to measure for hose and finish plumbing it up and then I guess I will Install the B&M Megashifter. May be the trans will be ready to put back in by then.?>?>?>?>

Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Well, Trans still in pieces but I did get the shifter installed. Crazy little relay they give you to put in place of the MLPS....


Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Joined: Jun 2006
Posts: 576
Likes: 4
From: Gobles, Michigan
Car: 92 Ttop Z28
Engine: Cammed 6.0
Transmission: T-56
Axle/Gears: Built 10 bolt-3.90s w/ PBR discs
Re: My 1989 IROC LS1/4L60E swap
With a properly set rev limiter, I am not sure how a shifter could cause engine failure with a electronically controlled trans....
Supreme Member
Joined: Apr 2013
Posts: 1,353
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From: North Salt Lake
Car: '86 Camaro, '94 Camaro, 3 others
Engine: LG4 ->L29, L32->LR4, L36, LG4, L31
Transmission: 700R-4, T5WC, 4L80E, SM465, 4L60E
Axle/Gears: 3.42, 3.23, WTB/WTT 2.93
Re: My 1989 IROC LS1/4L60E swap
I didn't see the claim that the B&M cost a rev-limited engine, but I know the Megashifter takes some learning. I'd guess anyone who installs one will redline first gear the very first time they drive with the new shifter. That would be an easy over-rev. And why manually upshift at WOT anyway? That's what the governor or PCM is for.
Re: My 1989 IROC LS1/4L60E swap
We were at a party late at night Jason went to make a smoke run in my car(82 Camaro). . He didnt know how to work the shifter and drove it at highway speeds for about 40 miles in 2nd gear. The next day it started knocking. Jazzdad should remember.. I told him about it and our buddy Rick helped me go through it when the shop was slow.No rev limiter on this one 
It wasn't the shifters fault

It wasn't the shifters fault
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Ahhhhh, OK. I remember you swapping engines but I didn't remember why. DUDE!! Do you know how many times i've slept since then??? DAMN! I feel old, that was 20 years ago!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Trans is back together so may be today I can get it installed??? Suppossed to be 101 degrees here today!!!!!
Re: My 1989 IROC LS1/4L60E swap
He came back and said "something is wrong with your car everytime I let of the gas it felt like someone slammed on the brakes."
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Alright, trans is back in. Need to bleed the brakes and get front end aligned. Before I do that, Now that I cut 1/2 a coil off the front springs it sits lower than I wanted. The best correction to me would be 1" drop springs in the rear and that would bring it close to level. Anyone with recomendations for 1" drop springs for the rear???
Thanks in advance.
Thanks in advance.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Thanks Poket but that would be too much. I ordered a set of Hotchkis springs for a dedicated 1" drop. I really did not want to drop the rear at all but after taking the 1/2 coil out of the front it makes the rear just look silly. I hate lowered cars but the 1" drop should level it out.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Well I guess I am stumped....... All of these wiring diagrams I am finding for hooking up the A/C circut are for 99-01 PCMs. Mine is a 98. Mainly missing the #43 pin whitch is A/C clutch relay control (ground from PCM to relay). If anyone has a diagram for a 98 I would be forever thankful!!
Re: My 1989 IROC LS1/4L60E swap
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Thanks Bro! Well fun!In the midst of me trying to do this while at work being disstracted by phones and customers I realized that I had soldered some wires in the wrong location (following 99-up diagrams). Not such a bad problem other than I cut off the lables telling me what wire went to what pin location at the PCM! Now to trace each wire back to PCM and start over with this relay, POOP! After doing all the wiring for this swap I feel now that it was easy. Now I have 5 Wires kicking my a$$! I refuse to drive her without A/C, 107 degrees with heat index today!
Re: My 1989 IROC LS1/4L60E swap
I know, I haven touched the car in weeks because its hot as he double hockey sticks out there. My car just needs some tweekeing and its ready. I also went back to school and have noooo time.
You will get there the hard work is done. You just need a little tweaking. You will enjoy your car a lot more knowing you did the work and now know your car inside and out.
You will get there the hard work is done. You just need a little tweaking. You will enjoy your car a lot more knowing you did the work and now know your car inside and out.
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
I just wanted to add that I read somewhere on this forum that you could swap front and rear wheels to bring the front wheels back in after the ls1 brake swap, THIS IS FALSE! the rear wheel on the front LOCKS the wheel against the caliper. NO BUENO!
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Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
Can anyone tell me the number of the connector for the A/C wiring that comes out of the firewall directly behind the passenger cylinder head? It has a DK Green, LT Green and Black wire. The other end of this harness has a blue wire that goes to the High Pressure switch (not being used) and a big fat black wire that I have no clue where it goes. It is the ground for the blower motor, I am not sure where it belongs, Cyl Head, Chasis??
I also noticed I left out the Hot wire to the A/C fan Relay. From what I can tell it had a fusable link at the end and probably went straight to the starter?? Any Idea What the amperage should be on this wire?
So What I am trying to find out is where did the factory have the ground for the blower motor and what amp fuse to put on the Big Red a/c relay wire?
Thanks all.
I also noticed I left out the Hot wire to the A/C fan Relay. From what I can tell it had a fusable link at the end and probably went straight to the starter?? Any Idea What the amperage should be on this wire?
So What I am trying to find out is where did the factory have the ground for the blower motor and what amp fuse to put on the Big Red a/c relay wire?
Thanks all.
Last edited by jazzdadss; Jul 30, 2013 at 08:56 AM.
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Joined: Mar 2007
Posts: 1,237
Likes: 7
From: Apopka, Florida
Car: 1989 Pontiac Trans Am GTA
Engine: cammed LS1
Transmission: Monster SS 4L65E
Axle/Gears: 9 bolt posi w/ 3.70 gears
Re: My 1989 IROC LS1/4L60E swap
Have you tried PM'ing Pocket about your wiring questions? That probably what I would do since he is the wiring guru on here!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
I suppose I am going to have to, I realy hate bugging people. I thought I had it all figured out but something has gone arie!! Everything works but when I activate the A/C the engine idle jumps to 1500 rpm and trouble codes start popping up. The A/C clutch kicks in and it blows cool air but something is wrong...
P0121 = TP sensor
P1545 = A/C clutch relay control circuit pressure switch
P1546 = A/C clutch status circuit low voltage.
Just shoot me now!
P0121 = TP sensor
P1545 = A/C clutch relay control circuit pressure switch
P1546 = A/C clutch status circuit low voltage.
Just shoot me now!
Thread Starter
Senior Member

Joined: Dec 2009
Posts: 702
Likes: 4
From: Texas
Car: 1989 IROC LSX
Engine: Swapped LS6 Forged by LME
Transmission: 4L65E
Axle/Gears: 3.73
Re: My 1989 IROC LS1/4L60E swap
OK, One more post for the day now that I have a headache from looking at schematics!!!
NOTE TO SELF! When using the LS harness, Make sure you do away with either the factory 3rd gen connector at the compressor (With the 1 Amp diode) OR do away with the in line 1 Amp Diode in the LS harness. It does not like having both! Did away with the third gen plug and ran the circuit back thru the clutch cycling switch and the High pressure cut out switch on the compressor. Out of the cut out switch thru green w/white wire to LS PCM.
NOW everything works, No codes, Idle is down where it is suppossed to be.
I hope this helps someone else down the road. You could learn a lot thru my stupidity.LOL!
NOTE TO SELF! When using the LS harness, Make sure you do away with either the factory 3rd gen connector at the compressor (With the 1 Amp diode) OR do away with the in line 1 Amp Diode in the LS harness. It does not like having both! Did away with the third gen plug and ran the circuit back thru the clutch cycling switch and the High pressure cut out switch on the compressor. Out of the cut out switch thru green w/white wire to LS PCM.
NOW everything works, No codes, Idle is down where it is suppossed to be.
I hope this helps someone else down the road. You could learn a lot thru my stupidity.LOL!










Glad I could help.
