CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond

Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
Nice!
Does that mean the LS swap is off?
I don't know that it could make that much of a come back! Hopefully it only means the drive to Moab just got a little less difficult.

Hope to hell the fuel mileage improves. Now that would be outstanding.
 
A healthy, stock TBI 350 is a much better engine than people want to give them credit for.

Martin
 
Yeah I'm excited to finally experience that.

Although it's still a wore out old motor. Flipping through the service manual looking for tune up info I found a listing of minimum acceptable oil pressure at idle, 2000rpm, & 4000rpm. I'm running just a touch better than those values.

I also think it's a bit of a testimemt that the truck still ran as well as it did even with the timing jacked up.
 
Wow, that's good for you and your truck! What spark plugs are you using. I returned to the stock AC Delco plugs on my Mr. Goodwrench 350 and it made a big difference in the way the motor was running when I switched from a carburetor to TBI.
 
Wow, that's good for you and your truck! What spark plugs are you using. I returned to the stock AC Delco plugs on my Mr. Goodwrench 350 and it made a big difference in the way the motor was running when I switched from a carburetor to TBI.
I had some AC Delco rapidfire plugs to put in but for some reason 3 of them had different electrodes even though the part numbers were all the same. I bought them 3yrs ago so unfortunately I didn't have any exchange/refund opportunity. So I ended up with some NGK spark plugs. The cap and rotor are AC Delco tho.

I bought all of the tune-up stuff 3yrs ago but then never installed any of it. I had just decided that since the truck was running as good as could be expected (or so I thought), I would just leave it alone. When I found the roached plug wires I figured it was time to just get it done. Too bad that didn't happen 3yrs ago. :doah:
 
Glad that woke the truck up a little bit:thumb:

It always makes me happy to find out something like that.
 
I'm glad it worked out. I hate when you're sure you know the problem and then it ends up not being the case. I was afraid that was going to happen this time around. Luckily it all worked out.

I'm still not sure what impresses me most, the quiet motor or how much more pull the motor has. Although I suppose when we start driving in the mountain passes it will hopefully be the power that impresses me most.
 
I had to edit my previous post about fixing the timing. I said the PO had it set at 12° Before Top Dead Center (BTDC), and I should have said AFTER Top Dead Center (ATDC). I gave myself a momentary panic that I had screwed up the timing myself, so I had to double check.

timing-tab.jpg


So the red line is where I found the timing to be and the blue line is where I set it. The factory spec is 0° but I was shooting for 4° due to living at 5000ft and wheeling at 8000ft to 11000ft. I ended up at about 5° because I probably bumped the distributor tightening the clamp.

Speaking of which, the bolt for the distributor clamp is a BITCH to get to. I have my trusty distributor wrench that served me so well all those years with the carburetor and HEI with the coil on the cap. Between the TBI fuel lines, heater core fitting, and wiring harness that wrench just didn't cut it. Finally just had to use a regular open end wrench. Which is why I didn't bother trying to bump the timing back that 1° to hit 4° BTDC.
 
I can honestly say, setting timing/getting to that bolt, is one of my least favorite things to do.
 
I finally used a 2x4 laid across the fenders and the flat panel from a creeper laid between the board and the core support. It was quite comfortable then and easier to reach the bolt. Still hotter than hell on my fingers because I was eager for a test drive and I didn't want to wait for the motor to cool down. :D
 
You'll be better off at 5 degrees than 4, so long as you don't start detonating.

Martin
 
It helps that I also just redid the regulator and both fuel pumps are new. I'm not afraid of too much advance; with carb in the K5 I ran as much advance as the starter would handle. IIRC around 18 or 20.
 
Scott, have you done a weld on brace yet? Curious to see what is needed to be done.

Only a 2wd frame guy will know what I'm talking about. :deal:
 
Is this all at idle? I set mine at 38 degrees btdc at 3k rpms with vac advance hooked up on carbed engine. Its at like 30 btdc at idle with vac advance plugged back in and runs awesome.
 
Is this all at idle? I set mine at 38 degrees btdc at 3k rpms with vac advance hooked up on carbed engine. Its at like 30 btdc at idle with vac advance plugged back in and runs awesome.

It's different for TBI -- the computer does all the advancing, no mechanical weights or vacuum. On the TBI you just set the base (idle) timing with the wire disconnected, and then the computer controls the advance in the dizzy when it's reconnected.

-- A
 
Scott, have you done a weld on brace yet? Curious to see what is needed to be done.

Only a 2wd frame guy will know what I'm talking about. :deal:
Hmmm, no. I may regret it, but I haven't. I just have the bolt-on brace. I guess I'm hoping the bolt-on brace and hydro-assist will hold off any problems.

Hmm I think maybe I should check out the timing on mine.
burnout

Is this all at idle? I set mine at 38 degrees btdc at 3k rpms with vac advance hooked up on carbed engine. Its at like 30 btdc at idle with vac advance plugged back in and runs awesome.
Yeah, pretty much what Dremu said. The idle is set without the computer input by unplugging the wire. The computer takes over timing once engine is running >400 RPM. The timing I'm setting with the wire unplugged is the base timing. The computer doesn't really know what I have the base timing set to, it just adds the timing to it as it's programmed to.

So at a given engine condition the computer is programmed to add in 10 degrees timing. As far as it knows it is adding 10 degrees to the baseline 0 degrees. But in reality because I have it set with base timing of 5, it is really jumping the timing up to 15 degrees.

Based on the before and after timing I was observing the computer must add in over 10 degrees of timing at idle. I can't really give a number because it's off the scale of the timing tab.
 

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