1989 Build In Progress

[Reddrig]

Started to pull out the old motor. I posted another question about Trans Locup after the new motor is in, will I loose the lockup? I heard the TBI trucks are electronic? What do I need to do to still have 4th lockup after the new motor goes in?

 

[Reddrig]

Motor is out! I posted a question in the 89 Forum about the wire harness, what have other people done with the harness as far as hacking it up for aux things like wipers and so on? My Sniper is self contained and everything runs off that harness, just needs power and ignition switch.

 

[6872xtc]

I don't really have a good answer for you. I pulled the TBI out of my '90 and installed a Proflo4. I worked to keep my electric speedometer in tact while removing the factory TBI wiring. My lock-up worked before and after, but I honestly wonder if the transmission has been modified.
I did use the factory fuel pump relay with my swap which kept the fuse for it in the fuse panel. It just needed some changes to work.

I don't know if my cruise would work though, as I haven't put the stud on the throttle lever to try it.
Everything thing else works fine. I didn't mess with anything that didn't have to do with the TBI.

 

[Reddrig]

So I have a mechanical speedo I believe, my oil pressure will be a new gauge and my engine temp sensor I will reuse. The big one is the trans lock up, I located the wiring for the lock up in the harness. Not sure if I can just cut all the rest of the harness and just leave what I want? Not sure if cutting out everything will disable what I want to keep? The trans lock up scares me, don’t want to burn up the trans.

 

[6872xtc]

Yes, you have a mechanical speedometer, but there is a optical sensor in the speedometer head that gives vehicle speed to the ECM. It can come into play for lock-up. (I think)
I am still using my stock gauges. The gauge and the ECM have different temp sensors with the TBI. The one in the cylinder head is for the temperature gauge. I kept the oil pressure sender for the gauge.

I would get it running and check for lock-up of the converter.

 

[Reddrig]

So I’m going to run a separate oil pressure gauge with a sandwich style adaptor. I’m not sure about the speedo playing a part in lock up either? I’m guessing stuff like wipers will still work if I cut everything out of the harness? Hopefully someone can answer the lock up question with certainty. Below is my new oil pressure gauge and sandwich adaptor which will also allow me to run temp if I want. My sniper is stand alone at this point so once I figure lock up out, I’ll be close.

https://www.glowshiftdirect.com/black-blue-maxtow-oil-pressure-gauge/
https://www.glowshiftdirect.com/oil-filter-sandwich-adapter-for-chevrolet-small-block-305-350/

 

[6872xtc]

I am wondering why you are buying the sandwich adapter when there is an 1/8" NPT port in the top rear of every small block that I know of. Most blocks that I remember seeing have a 1/4" NPT just above the filter pad too, if you want a 2nd port.

 

[Reddrig]

Did not know the port was there, I’ll check it out and return the adaptor if that works out. The adaptor does have multiple ports which might come in handy later.

 

[mrk5]

For the switched power to the Sniper I used a pink& black wire that comes off the harness at the firewall. The firewall connection is below the brake booster. This wire normally provides power for the TBI sensors. I've marked it below with the pink wire.



The rest of the TBI harness I removed. I found something random to plug the big hole where the harness passes thru the firewall.

 

[Reddrig]

Think I may have figured out my Lockup also for any one else looking.

 

[Reddrig]

For the switched power to the Sniper I used a pink& black wire that comes off the harness at the firewall. The firewall connection is below the brake booster. This wire normally provides power for the TBI sensors. I've marked it below with the pink wire.

View attachment 340695

The rest of the TBI harness I removed. I found something random to plug the big hole where the harness passes thru the firewall.

Great info, so excuse my ignorance, my harness separates from the TBI stuff through that large hole and then has a merge point with more of the harness that feeds to that junction just to the right of the brake booster. Did you physically cut the harness that feeds through the hole the TBI stuff runs through? Did you leave the other wiring in place by the booster? That other harness near the booster seems to control most of the aux functions like wipers and what not and possibly fuel pump.

 

[mrk5]

I can't remember what I did with wiring off that plug that went to the TBI and I can't tell from my pictures. I do remember that I just cut what needed cut from the TBI harness to get it out. I thought some about trying to save it for resale, but in the end just physically cut it where needed. If I cut any wiring that came from the plug hear the brake booster I would have capped it off with shrink wrap.

Here are some wiring diagrams that might help you.

 

[Reddrig]

Tore out the AC system and replacing with a delete cover, looks like I may have a small leak with the core. I’m very disappointed, every time I take a step forward I go backwards again..

 

[6872xtc]

Sometimes it's difficult to remember that these trucks are 30 years old or more. A 1991 is almost 30 years old, so lots of us have one older.

 

[sreidmx]

This is going to be nice when its done, that is a stout small block for sure, great choice.

 

[Reddrig]

Well spent 5 hours scrapping and grinding, one more day of prep and then some Por15 for the engine bay. Time for a cocktail!

 

[Reddrig]

So I spent all of today finishing the prep work, degreaser, metal prep and paint tomorrow. Looking forward to the results.

 

[mrk5]

Looks clean

 

[Reddrig]

Finished the Engine Bay with Por15, lots of prep work with this stuff. Turned out really good and should look good with the engine in. Gonna be a few weeks before I can get motor in. Still need to finish fuel delivery also.

 

[6872xtc]

Should look great when it's all back together!