1987 R10 LS swap info

[dangOl'dodge]

Think im gonna try the seperate fuse block.. At least for the wires i need to run manually. Really not comfortable pulling the whole harness apart if possible. Did you folow the custom fuse block instructions on lt1 swap?

Everyone i ask says they are not sure because they did a custom fuse block so maybe thats what il do,

Howd you hook up ignition wires did you splice them in to the plug in under steering column or run them directly to ignition and run new grounds too?

Maybe i could try using the ignition outta the donor truck and seeing if i can get anything to happen.

Although im thinking I shouldn't have to jump to starter wire from truck to fusebox if the ignition powers up the fuses when hot shouldn't it just power up the starter relay and turn the engibe over on its own?

 

[yevgenievich]

instructions from lt1swap will work if followed correctly.

Although im thinking I shouldn't have to jump to starter wire from truck to fusebox if the ignition powers up the fuses when hot shouldn't it just power up the starter relay and turn the engibe over on its own?

If you want to remain with factory wiring, you have to probe your constant power, switched power and ground wires as a first step in trouble shooting a swap.

I had used part of the wiring from a new harness for ignition and tied to existing wires under the dash. If going with a custom fuse block, you will at least have two relays with it.

While cranking, do you know if you get tach signal? If computer is not outputting a tach signal it could indicate lack of power to the computer or non working crank sensor

As a side note, The picture of the wiring that you had attached is too small to read, so I could not comment anything regarding what is listed on it.

 

[74propu]

Think im gonna try the seperate fuse block.. At least for the wires i need to run manually. Really not comfortable pulling the whole harness apart if possible. Did you folow the custom fuse block instructions on lt1 swap?

Everyone i ask says they are not sure because they did a custom fuse block so maybe thats what il do,

Howd you hook up ignition wires did you splice them in to the plug in under steering column or run them directly to ignition and run new grounds too?

Maybe i could try using the ignition outta the donor truck and seeing if i can get anything to happen.

Although im thinking I shouldn't have to jump to starter wire from truck to fusebox if the ignition powers up the fuses when hot shouldn't it just power up the starter relay and turn the engibe over on its own?

I used the pin out and fuse block set up form lt1 swap as a stand alone harness and used the truck harness for the fuel pump relay the ecm just runes the eng

 

[dangOl'dodge]

update... i ended up removing wire harness from truck, i contacted Adam Warren from LSXHarness.com and he talked me through the stand alone setup.. he was very patient and drew me up some simple wire diagrams for the 4 relays and 4 fuses on the block, would highly recommend his work!

connected a few wires that were coiled up for the ignition and fuel pump etc, and it fired up first click of the key!

Shout out to anyone who helped me in this thread and over on 67-72chevytrucks forum, Adam Warren @ LSXharness.com
Brendan Patten @ LT1Swap.com

Appreciate all the help!

Cory

 

[dougbert]

I will mod'ing my harness as per lt1swap.com and his instructions.

when I get things more done.


good thread here

 

[klroth025]

Update?

I hope to use this thread as an instruction manual for my project considering I have a '87 R10 4.3 tbi and a 2004 Silverado 4.8 4L60E donor truck. I guess my first question is... what is the final word on motor mounts. Are the frame brackets different? (some local people are saying they are not) I have seen some LS swap mounts move the engine back and lower for better weight distribution. Has anyone used these? Pro's and Con's? I have also seen info about oil pans needing to be changed to an LH8? oil pan. For cross member clearance, is this necessary?

 

[dougbert]

I used Dirty Dingo mounts, a set of pics starting at http://www.gmsquarebody.com/forum/showpost.php?p=294740&postcount=36 and beyond

at http://www.gmsquarebody.com/forum/showpost.php?p=294739&postcount=35 are pics of the engine encountering my cross member, but I have a K1500, not a C10 - they have different cross members

and pics of the empty engine bay with standard Chevy mounts in lower left at http://www.gmsquarebody.com/forum/showpost.php?p=292714&postcount=5

 

[dangOl'dodge]

Update?

I hope to use this thread as an instruction manual for my project considering I have a '87 R10 4.3 tbi and a 2004 Silverado 4.8 4L60E donor truck. I guess my first question is... what is the final word on motor mounts. Are the frame brackets different? (some local people are saying they are not) I have seen some LS swap mounts move the engine back and lower for better weight distribution. Has anyone used these? Pro's and Con's? I have also seen info about oil pans needing to be changed to an LH8? oil pan. For cross member clearance, is this necessary?

sorry for the late reply. truck has been parked in the snow bank all winter. never got the chance to get it running 100% last fall, gonna go at it again soon!


experiencing low fuel pressure (40psi ) and idle issues. will start by cleaning injectors and adding an exhaust to the truck, also fresh set of o2 sensors as one of my wires appear to be chaffed up! as for the question about the frame brackets, they look similar side by side but i was lucky enough to score a brand new set from a 305 of the same era for cheap so i didn't bother sticking around to see if the v6 brackets would work! engine fits pretty good with the 305 brackets and dirty dingo mounts, one of my manifolds is rubbing against the frame rails due to it having that EGR port sticking out of it, id say i will be buying a set of headers soon though, wondering what will fit the truck for cheap?

thinking about trying Fbody long tubes off eBay, from what i hear they hug the block pretty close... any one else have any experience with em?

 

[foamypirate]

sorry for the late reply. truck has been parked in the snow bank all winter. never got the chance to get it running 100% last fall, gonna go at it again soon!


experiencing low fuel pressure (40psi ) and idle issues. will start by cleaning injectors and adding an exhaust to the truck, also fresh set of o2 sensors as one of my wires appear to be chaffed up! as for the question about the frame brackets, they look similar side by side but i was lucky enough to score a brand new set from a 305 of the same era for cheap so i didn't bother sticking around to see if the v6 brackets would work! engine fits pretty good with the 305 brackets and dirty dingo mounts, one of my manifolds is rubbing against the frame rails due to it having that EGR port sticking out of it, id say i will be buying a set of headers soon though, wondering what will fit the truck for cheap?

thinking about trying Fbody long tubes off eBay, from what i hear they hug the block pretty close... any one else have any experience with em?

Not sure if you are dead set on headers or not, but Trailblazer/Envoy 5.3L manifolds, and LS3 manifolds will fit really well inside the frame rails, typically. You can usually find them for under $100 on ebay/cl/forums.

 

[dangOl'dodge]

Not sure if you are dead set on headers or not, but Trailblazer/Envoy 5.3L manifolds, and LS3 manifolds will fit really well inside the frame rails, typically. You can usually find them for under $100 on ebay/cl/forums.

well I'm not really dead set on anything just yet, are the trailblazer/envoy manifolds really that much different from the silverado pickup truck 5.3 manifolds?

these are the f body on eBay http://www.ebay.ca/itm/STAINLESS-LO...ash=item2368c8aa82:g:mS4AAOSwZAtXJqgl&vxp=mtr

 

[foamypirate]

well I'm not really dead set on anything just yet, are the trailblazer/envoy manifolds really that much different from the silverado pickup truck 5.3 manifolds?

these are the f body on eBay http://www.ebay.ca/itm/STAINLESS-LO...ash=item2368c8aa82:g:mS4AAOSwZAtXJqgl&vxp=mtr

I haven't used them first hand, but they are supposed to tuck in tighter. I personally went with the Hooker LS swap manifolds (PN 8501HKR), but they are around $300, so not really a budget piece, per se.

 

[dangOl'dodge]

so i thought id give an update on the manifold situation... after reviewing the prices and my options, i ended up going to the scrap yard and finding what i think was a 2005 silverado 4.8 and taking the passenger side manifold off that. it did not have the EGR valve in it and it fits like a glove!!

also last year i think i had mentioned the truck wasn't running very good, bank 2 fuel trim and 02 voltage levels were outta whack, 2 new o2 sensors on it last week and it seems to be running good now! hopefully thats all that was causing me trouble.

another question i was wondering was if i needed the transmission crossmember brace ( small bracket that goes from crossmember to top of frame on passenger side... I'm getting dual exhaust put on tomorrow and i couldn't install the brace due to the current exhaust set up, which is just temporary to move the truck around the yard, pipe is in the way... gonna have to get the exhaust man to install that brace while he's doing the exhaust if thats the case ($$$)

and lastly... i was wondering if i need to keep the speedo cable from the 87 if i get the abbott cable x setup? not sure exactly how it works but i know when i hook up my programmer to the obd2 port i can use that for a speedometer so i know the ls computer is getting a speed reading, does the cable x go off that or does it use that + original spedometer cable to get my speedometer working?