79 GMC Sierra LWB 6.0L swap

[79gmc5.3]

Originally Posted by glock35ipsc

Sorry, I got so busy this weekend I didn't go through all my emails! I can take a pic of the one in the Burb, it's the same setup as in the truck.

Thanks Buddy I appreciate it.

[glock35ipsc]

It looks like an additional bracket that is spot welded on to the existing brake light switch bracket. And the pad that is on the brake pedal that the plungers contact is a bolt-on piece. Hope this helps.

[79gmc5.3]

Thanks Bob. Well I drove it to the exhaust shop yesterday and all the way there I was thinking that this is not the way this should run but with straight exhaust I couldn't tell what was wrong. After the exhaust was finished and I was on my way home I could tell it was a dead skip, so after a little searching I discovered a bad coil. Replaced the coil and OMG!!! this thing is a beast! OK now I am satisfied. Need to fix the tach and speedo and I will finished with this swap!!!!!!!!! Sorry still no video but I will post one.

[menace121978]

right on buddy! you had me worried!! glad she's fixed... now about that video

[79gmc5.3]

Small update: Been a little disappointed at how my trans shifts so I took it to a trans shop today that I trust and the guy took one look at the fluid on the dip stick and said water in the fluid. After flushing 32 Qts through the trans it shifts like a new one. Also found out I have a 3.42 gear in the rear end so there is money I don't have to spend. Working on a video now! LOVE THAT 6.0 POWER!!!!!!!!!!!

[Devillusion]

sub'd.............might have to do this to both my trucks now. Dually might have to get a transplant to!

Love it. Keep up the good work

[79gmc5.3]

Hey guys been awhile, just been driving the truck! Runs, Sounds, and Drives great! But these Georgia summer days are killing me with no A/C. So I may need a little help with the wiring. I have 2 wires that are identified for A/C clutch and something else. What do I connect them to? Thanks in advance. I have a video but can't get it to upload.

[glock35ipsc]

Do not connect the AC through the PCM. I don't remember for sure, but somewhere around 2004 and up, the AC is controlled by a serial data signal through the PCM and the BCM (body control module) and the interior HVAC controls. I do know of one guy that tried to hook his up through the PCM and smoked it.

I have mine hooked up very simply. The green wire that ran to the original compressor..... run that to the green wire on the LS's compressor, and run the black to a ground. Done. I've been driving mine a lot running the AC, and have yet to have ANY issues with it. No problems at idle, no surging when the compressor locks up, no overheating at idle, nothing. Just hook up the green wires, ground, and go.

[nlped]

^^^ That, even I can do

[STOCKISH]

Thats the way I am doing mine too. I had the harness made without the A/C wiring in it just for that purpose. Cant wait for a big long smokey burnout video!!!

[79gmc5.3]

Hey guys, Been a while sense I posted, been watching a few of the builds. Had a problem the other day wanted to see if you guys might know what is wrong. Fuel line came off the fuel rail (the feed line) put it back on, now I have a skip. Checked the plugs installed a new set of plug wires, put a timing light on all the plug wires and all are the same "strobe" and still a skip. Have an OBDII code reader and no codes are read. Have not checked the fuel pressure so don't know if that is it. Any ideas? Thanks for the input.

[menace121978]

there he is! how ya been buddy?! as for the problem it sounds like there might be some debris or something clogging the injectors... my best guess anyways.

[79gmc5.3]

Originally Posted by menace121978

there he is! how ya been buddy?! as for the problem it sounds like there might be some debris or something clogging the injectors... my best guess anyways.

Just been driving the truck. I get a lot of people asking me about the swap. They can't believe it when I raise the hood at some of the weekend drive-ins As for the injectors any way to check them?

[mcbassin]

Glad to hear you have been enjoying your truck. Not sure about checking the injectors. When you stand on it do you get the same "skip". Can you hear it at idle? I'm wondering about the compression. I know of one 2001 engine that actually had a bent valve. Of course it had a dead miss. From what your telling us, it's hard to tell if it's electical or fuel? Wish I could help more.

[79gmc5.3]

Originally Posted by mcbassin

Glad to hear you have been enjoying your truck. Not sure about checking the injectors. When you stand on it do you get the same "skip". Can you hear it at idle? I'm wondering about the compression. I know of one 2001 engine that actually had a bent valve. Of course it had a dead miss. From what your telling us, it's hard to tell if it's electical or fuel? Wish I could help more.

Don't think it is compression because the skip is minor. When I first got it running I had a bad coil, dead miss. Now it seems a cylinder is lean. I am leaning towards an injector clogged or going bad. All the spark plugs are tan in color indicating a lean condition. Have not checked the fuel pressure, that may also be it. I am useing a 255 lph walbro pump so that should supply enough fuel, unless something is clogged. I'll just keep marking things off the list till I find the problem.

[nlped]

Check the fuel pressure. The walbro pump is a "volume" pump that your regulator controls the pressure. I would check the pressure at the fuel rail first. If all of the plugs are showing signs of a lean condition, that is exactly what direction I would start with. Also, you can pull the injectors and do a visual inspection of the spray side of the injector for trash, it may be something as simple as that.

Good Luck and keep us posted!

Ed

[79gmc5.3]

Originally Posted by nlped

Check the fuel pressure. The walbro pump is a "volume" pump that your regulator controls the pressure. I would check the pressure at the fuel rail first. If all of the plugs are showing signs of a lean condition, that is exactly what direction I would start with. Also, you can pull the injectors and do a visual inspection of the spray side of the injector for trash, it may be something as simple as that.

Good Luck and keep us posted!

Ed

Well I checked the fuel pressure and 58 psi at idle with the vacuum plugged changed the coils, wires, and injectors with no change. compression is equal on all cylinders and good. Someone told me it could be the cam sensor what do you guys think about that. HELP!!! I am running out of things to change.

[79gmc5.3]

Well I have been pulling my hair out trying to find this skip. Took to a shop to see if they could figure it out and after about an hour it turned out to be a cracked spark plug. So now I am riding again. Want to start on the chassis now just want to take the body roll out of it. What is the best way to get better handling from these squarebodies.

[STOCKISH]

Drop it buddy! Larger diameter wheels with lower profile tires, poly bushings and front and rear sway bars. Mine handles like it's on rails! I love taking an exit ramp at speeds where the Mustang in front of me is on the brakes. Lots of fun for sure.

[menace121978]

Originally Posted by 1972SuperCheyenne

Drop it buddy! Larger diameter wheels with lower profile tires, poly bushings and front and rear sway bars. Mine handles like it's on rails! I love taking an exit ramp at speeds where the Mustang in front of me is on the brakes. Lots of fun for sure.

x2!

and it'll look sooooo sweeeeet!!!!!

[79gmc5.3]

Originally Posted by 1972SuperCheyenne

Drop it buddy! Larger diameter wheels with lower profile tires, poly bushings and front and rear sway bars. Mine handles like it's on rails! I love taking an exit ramp at speeds where the Mustang in front of me is on the brakes. Lots of fun for sure.

Guys your killing me......... I really don't need to spend that kind of money! You need to tell me that a LWB needs to stay with the stock height and wheels and tires............ Come on work with me here!

[STOCKISH]

Originally Posted by 79gmc5.3

Guys thanks for the great ideas!......... I really want to spend that kind of money! I now believe you when you tell me that a LWB needs to be dropped with big wheels and low profile tires............ Come on, any more good ideas?!

There man, I fixed it for ya!

[menace121978]

perfect!

[87chevy.com]

Originally Posted by 79gmc5.3

Hey guys been awhile, just been driving the truck! Runs, Sounds, and Drives great! But these Georgia summer days are killing me with no A/C. So I may need a little help with the wiring. I have 2 wires that are identified for A/C clutch and something else. What do I connect them to? Thanks in advance. I have a video but can't get it to upload.

I'm running my a/c through the computer no problem, Its wired in almost factory like with the exception of the high pressure switch. Its hardwired in so the system functions like normal. What year is your PCM? Maybe I can look at a diagram figure something out for your unless you got your situation solved.
I ran the a/c at first w/o using the pcm and the truck would want to die at idle... because of the drag caused by the compressor.. once I stared at the diagram... I was like why didnt I do this sooner.

clint

[79gmc5.3]

Originally Posted by 87chevy.com

I'm running my a/c through the computer no problem, Its wired in almost factory like with the exception of the high pressure switch. Its hardwired in so the system functions like normal. What year is your PCM? Maybe I can look at a diagram figure something out for your unless you got your situation solved.
I ran the a/c at first w/o using the pcm and the truck would want to die at idle... because of the drag caused by the compressor.. once I stared at the diagram... I was like why didnt I do this sooner.

clint

Thanks Clint, The PCM is from a 2003 GMC Denali with rear air. Of course I not using the rear air.