Metal's LSx swap; Finally up and running!

[y5mgisi]

I have some progress pictures.

After pulling all the un-needed wires from the harness, I some how managed to end up with the oil press. sensor wire clipped. I followed directions exactly. In fact, I ended up clipping a few wires in addition to the ones listed on Lt1swap.com.

Since it seems the pcm doesnt care about oil press. Can I just run the wire from the LSx motor's sensor and connect it with the 87 oil press sensor wire?

Nope. You have to use the sensor for your 87. You need to unscrew the LS sensor, get the requiered adapter, and screw the 87's in its place.

I also ended up not removing any wires from the alternator plug. I remember that on the 87 its only a one or two wire deal. y5mgisi ened up just connecting the 1 brown wire I think?

I can hardly remember yesterday... Anyway, most folks will leave the LS alternater wiring in the harness and let the computer work the alternator. When i got my harness it was already removed. Mine ended up being sucky cause i ended up having to wire in a "charge" light to get the alternator to charge instead of justletting the computer do it. Im not 100% sure what you do with the 87's original wire. Thats something you will have to find out with google.

I also don't have C2-D9- pink ign. 1 voltage. I did have all the rest of them.


I was going to start to tape and loom everything back up. However, I can't find non adhesive harness tape anywhere locally. I am just going to have to order from amazon or something I guess.

Just a few shots cleaning up the motor.

Took off the power steering and cleaned it up. Replaced the O-rings for the pressure line too.

I definitely am going to do the service bulletin for the Knock sensor. It is just a little bit crusty in the rear one. Doesn't look too bad though.

Good trick to use is the caps for the knock sensors put a bead of silicone around the bottom.

For sure. Pretty much mandatory.

 

[metalneverdies]

Well I tired the weld a nut / nipple method. I clearly suck at that. Just booger it in there every one said on ls1tech said. It won't stick to aluminum.

Well, it stuck and kinda screwed up the surface. I am quite tempted to take the engine to a machine shop to have them pull the bolts out.

What the hell was gm thinking using such small bolts.

 

[sweetk30]

3/8" nuts also I find work best .

crank up the welder heat .

let it cool 100%

then heat the head up around the bolt .

slow try and turn out the bolt working back / forth .

some take 2-3 nuts welded on as there is loctight on them from factory .

 

[metalneverdies]

3/8" nuts also I find work best .

crank up the welder heat .

let it cool 100%

then heat the head up around the bolt .

slow try and turn out the bolt working back / forth .

some take 2-3 nuts welded on as there is loctight on them from factory .

I used a 1/4" x 20 nut. Its all I had.

When you say crank up the heat, how high? I had the amp dial set to the 5 and 6 position. Feed speed at 30 on my hobart 190. Is that overkill?

 

[sweetk30]

you need the bigger nuts . trust me I do it all the time.

sounds like welder is good . just need more surface area the bigger nut will give you .

 

[metalneverdies]

you need the bigger nuts . trust me I do it all the time.

sounds like welder is good . just need more surface area the bigger nut will give you .

Ok. I will super glue it to the head so I don't have to hold it.

Feed speed still ok? It was so hot that I had to pull the gun back as the wire was melting off almost faster than it came out.

I was afraid to put too much weld in too fast and weld to the aluminum though.

 

[metalneverdies]

Not much progress to report. I ended up having to take the motor to the machine shop to get the two stuck bolts out. One needed a helicoil.

I gave it a try with some quality easy outs borrowed from Cruz89k5 but I had no luck getting the bolts out myself.

Gathered a few more cheap parts.

I am kind of at a loss with which way to wire tgings up. Tempted to run the stock 87 fuse block for a few things then use the extra fuse blocks recommened on lt1swap for the Injectors and ecm. I am at a loss on how to wire it all up correctly though.

I also noticed I have a vss sensor in the truck already for thr factory cruise setup. Any reason I can't just splice the lsx harness vss wires into that sensor?

Also, where did you guys route your factory evap / purge line to? On the 87 it goes to a vac. Line on the tbi. There is no where to plug in on the lsx.

 

[y5mgisi]

Use the 87's fuse block only to trigger the relays. I was under the impression that 90 was the first year for electronic speedo. So im not quite sure what you have. If you modify the harness the way lt1swap has it, you dont need to tie almost anything from the 87 into the LS harness.

 

[metalneverdies]

Use the 87's fuse block only to trigger the relays. I was under the impression that 90 was the first year for electronic speedo. So im not quite sure what you have. If you modify the harness the way lt1swap has it, you dont need to tie almost anything from the 87 into the LS harness.

87 has mechanical speedo but still has a vss feeding a signal to pcm for cruise. I don't know of it uses it for anything else.

 

[broham]

I also noticed I have a vss sensor in the truck already for thr factory cruise setup. Any reason I can't just splice the lsx harness vss wires into that sensor?

I think this Speedo based VSS sensor has a lower pulse/mile than the later LSx. If i remember correctly, these TBI systems are 1000/mile while the later ones, based on the ABS system, are 4000/mile. The amplitude and shape my also be different.

good luck!

 

[y5mgisi]

Its something like that. It only really matters if you are using a electronic trans. And you are using a 700r4 IIRC so you can have your computer programed to accept almost any PPM.

 

[metalneverdies]

Its something like that. It only really matters if you are using a electronic trans. And you are using a 700r4 IIRC so you can have your computer programed to accept almost any PPM.

I Will have to see if eaglemark can program my pcm for that.

 

[y5mgisi]

Do it. He is good and has good communication!

 

[metalneverdies]

Nothing crazy exciting. Got the engine out, working on cleaning up the engine bay. Sooooo greasy.

I am going to start working on pulling wires not needed. Then patching in my harness. Still a bit confused on building my fuse blocks for the stand alone system. No clue how to crimp the long stip of connectors included. I assume that one is the power distribution side.

My wife helped pull the engine. Worked the lift while I guided the engine out. Kind of a tight fit leaving the manifolds on.

 

[metalneverdies]

I have been slamming my head against the wall trying to figure out the wiring situation. I cant decide which circuits to keep with the tbi pin outs.

Do I even need to keep the little 6 pin connector near the two tbi ecm connectors? Looks like it runs trans and brake position sensor.

I also cant decide if its ok to cut off the wires coming up from the transmission.

Is there any guide to which wires to cut coming out ofbthe drivers side fuse block?

The spliced brown/ wht and orange/white wires running to the fuse block can be cut out?

 

[metalneverdies]

Well after another solid 16 hours of online research I have whittled down the number of wires left on TBI side of the harness. Still have a couple of wires to sort through on the bulkhead.

As soon as I get my engine mount adapters I can cut my wires to length and mount up my fuse box.

I should have the Alternator wired up to be controlled by the ECM. I just need to figure out how to get the Stock 87 volt meter to read correctly as I will be eliminating most of the wiring for the 87 alternator.

I am debating ordering the TCC lockup kit from Bowtie Overdrives. However, I snipped the TCC connectors long enough that I should be able to run them into the cab and run a manual lockup switch. Just not really sure how to do that yet. Or when to even lockup the trans. I have seen kits that lockup in 3rd and 4th and kits that only lock in 4th. No clue how or when to use the lockup. Any one have any suggestions?

I am also still a bit fuzzy on if I need the purple wire on BLUE connector pin # 33. TCC Brake switch. I don't think the LSx computer needs to know about that? (Running a 700R4 in manual lockup or in standalone)

I cant decide if it is worth hooking up the P/N safety switch on the LSx computer or not. Is it needed for Emissions/safety inspection?

 

[y5mgisi]

If I remember right, on my 90 at least, the volt gauge got its voltage source from somewhere else. The p/n is up for debate. I think most folks will say you should hook it up. Are you going to be running a speed sensor?

 

[metalneverdies]

If I remember right, on my 90 at least, the volt gauge got its voltage source from somewhere else. The p/n is up for debate. I think most folks will say you should hook it up. Are you going to be running a speed sensor?

Hmm. Guess its back to more reading and wiring diagrams for the volt gauge.


I plan to get a dakota digital VSS and have eagle mark tune my PCM for it.

 

[metalneverdies]

I think I may hook the PCM up to battery power from the original orange wires that powered the 87 pcm. That will put it on ots own fused circuit.

Original harness:
A7: fuel pump relay control: guess I can snip that off at the bulk head?

B10: p/n switch. Can I just run that wire to the LSx pcm p/n wire and solder together?

B1 & c16: splice together to one wire with B+. Potential lsx PCM power. If I dont route it that way I guess I can just snip off at bulk head.

C9: crank input. Runs to the bulk head. Do I need this wire?

A6: SES. I believe I can solder that straight to SES light on new PCM.

B8 A/C on: runs to EVAP pressure switch. I cant find the other end of the connector anywhere. Do I need this wire? Connector is near the bulkhead and runs into other engine connectors. Cant find where the other half connects or goes to.

Any advice?

 

[metalneverdies]

Quick side note. Ordered my VSS adaptor today. Unfortunately I didn't think to check at any other sites. It is cheaper from summit than from the home website.

http://www.dakotadigital.com/index....category_id=-1/home_id=-1/mode=prod/prd57.htm

Currently trying to track down which AN conversion fittings I need to go from the Fuel hard line fittings near the passengers floor board to AN-6.