CK5
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'91 K5 Four Wheel Camper

This is the build for my 1991 V1500 Blazer, AKA the K5.3. It started out life being sold to the U.S. Government with a 350 TBI/700r4/241 combo. 4 years with a 5.3/700r4 Combo and now moving to an 8.1L Vortec and NV4500 5-speed.
Drive shaft gonna clear

Yeah, I was just looking at that wondering if that passenger side cross-over pipe was gonna hit the front shaft when it's articulating. Gonna be close if it doesn't hit.

I really like how you painted the valve covers to match the orange block. You know I'm always game for an 8.1/NV4500 swap :waytogo:
 
Talked to Larry after getting back with the truck. Front shaft clearance is a non issue. Gobs of room. Rear might get close at the axle to a muffler at full stuff. We had already planned on adding another leaf or two to level it out. Shouldnt be an issue after.
 
I see it now pass side is up against bell housing, plenty of space. Didn't help my visually challenged self that was lose on other end. Good look system
 
I see it now pass side is up against bell housing, plenty of space. Didn't help my visually challenged self that was lose on other end. Good look system
Well actually upon further review with the front shaft in place it's probably going to be an issue. It's got only a few inches of up travel before contact. It's going to need adjusted. Need to sort out a couple of other items first.
 
Well actually upon further review with the front shaft in place it's probably going to be an issue. It's got only a few inches of up travel before contact. It's going to need adjusted. Need to sort out a couple of other items first.
It will self clearance.
 
sure does :rotfl:
and never noticed a difference in performance.
That’s exactly what would happen to Rob’s :rotfl:. When it was on the rack it looked like the front shaft would clear but once I got it home and actually screwed the shaft in, it was no bueno. We just need to run it out to the exhaust guy for adjustment once we get everything else dialed in.

So, the 8.1 swap has been consummated now :waytogo:
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Stopped by Larry's place on the way home to pick up a tool he needed and give the Blazer a spin. Larry has been working on dialing in little things. One of which is fuel pressure. He had driven it a little and it just felt like it was held back. Like lack of fuel or it just couldn't breathe. Fuel pressure check proved it, low. Like 43 psi idling. Spec is 55-62 psi. It got cranked up. He's found 8.1's like more fuel pressure. It's at 68 now. He said it hauls.

Holy cow he's right. It's an animal. I took it for a spin hitting the main road around Pueblo West. I don't know how fast I was going because the drac module was unplugged but I knew it was exceeding the speed limit in 3rd. It never runs out of torque. Just pulls. As I expected it feels completely different. It's like it lost 2,000 pounds of weight. It moves out effortlessly. Sounds different too. Way more bass to the exhaust. Which is crazy since they are the same mufflers I had with the 5.3.

The funny thing is how well it takes to lug it in higher gears too. The 8.1 don't care. Roll around a corner onto another street in 3rd and it just pulls away. I did the same thing in 4th and it still didn't complain.

It's coming home after the trip to the exhaust shop. I've got all the electrical for the console and camper to reconnect. The flooring needs put back in, but I want to add some insulation to the floor to help with the heat in the summertime. Mechanically, it needs the rear output bushing in the t-case replaced. With the manual trans you can feel it clunk on the rear shaft when the clutch is disengaged and engaged. The rear cv joint is tight, but you can feel a little slop to the tailshaft housing. I still need to do the front shackles and bushings as well. Larry's working up the list for me to go after at my place.

Words really can express how thankful I am to Larry for taking on the swap. We both thought it would be an easier swap since the truck was already running a Howell harness and I had it ready to start installing the drivetrain pretty quickly by having the 5.3 and auto trans already out. Boy were we both wrong. It fought every step of the way. The engine cross member didn't fit right, which probably predicted that the engine was going to be tough to install and it was. The trans cross member didn't want to fit without massaging. Each step of the way proved to have some kind of issue that would require adjustments of some type. The might as well scope creep was real too. We ended up going deeper than we did for the 5.3 install. It proved the old saying on projects costing twice as much as you thought and twice the amount of time. I can't thank him enough for putting in all the effort over the last two months. He killed it.

Should be fun putting miles on it again.
 
Dude, right on page 1 of the 8.1L Resource Page I clearly spelled out ANY BBC manifold would fit an 8.1L :dunno:. If you’re putting an 8.1 in a square, get manifolds for a square with a 454 :waytogo:


- The L18 8.1L has the same foot print as older BBC engines and will bolt in the same as any other older SBC and BBC. In fact, the L18 will accept any exhaust manifold or header from older BBC engines. The starter motor from any older SBC and BBC for use with a 168 tooth flywheel will also fit the L18. Any transmission from an old PowerGlide, TH350, TH400 to Allison, to NV4500, etc. will bolt on to it as well.
Any concerns about melting the plug wires?
 
Any concerns about melting the plug wires?

No, not sure what they would melt on :dunno: There is more airgap with these wires than I've seen on most engines. These particular wires are on my K10, Suburban and Silverado HD. Great wires. You can lug the engine down to a really low RPM and they will not break down (what I mean by lugging it, is being in 3rd or 4th gear at 800/900 RPM while tipping into the throttle. Small cheap plug wires will cause the engine to hiccup, miss and buck leaving you saying "What the f*@K"). Especially the RayLar wires, those tiny things broke down easily. Went through a few sets of those before moving to the larger Taylors the small Raylar wires break down easy. 80 bux is a fair shake for 10 MM wires
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The FB 8.1L group is full of reports of failed wires, even on stock setups. Per the bro-science there, you must have the ceramic boot wires with headers. The factory 8.1 setups had the metal chimneys over the boots and heat shields over the manifolds and some still seem to have problems in heavy towing. A camper truck is kind of like mini-towing all the time, but maybe not enough constant load to make that kind of heat.

(I really wish I had more than a couple hundred miles of 8.1 experience! Still trying to learn.)
 
The FB 8.1L group is full of reports of failed wires, even on stock setups. Per the bro-science there, you must have the ceramic boot wires with headers. The factory 8.1 setups had the metal chimneys over the boots and heat shields over the manifolds and some still seem to have problems in heavy towing. A camper truck is kind of like mini-towing all the time, but maybe not enough constant load to make that kind of heat.

(I really wish I had more than a couple hundred miles of 8.1 experience! Still trying to learn.)
Ah, I see what you are saying. I think we’re talking two different things though. For what it is worth, we had a lot of burnt “open” plug wires on Workhorse RV chassis when the body builder (Winnebago, Fleetwood, etc.) didn’t have adequate grill openings for air flow. The engine bay got so hot the wires would burn open under heavy load. Not at the ends of the wire, but right smack in the middle of the wire. Usually cylinder #6 or #8. Oddly, enough we’ve also seen this a couple times on our new School Buses we build with the 8.8L although that applicate had plenty of air circulation in the engine bay so that one is still a mystery being investigated by PSI. Burnt open plug wire issues are entirely different than being burnt by the manifold. In any event, I haven’t had either issue on my 8.1s…….maybe yet. I don’t follow any of those FB groups very closely as its too time consuming to separate the straw from the manure …..and there is a lot of manure in those groups.

The OEM boot covers would be nice to have but Rob's 8.1 didn't come with wires to swipe them from. I do have those OEM metal boot covers on my 3 though come to think of it. Prolly need to find Rob some :thinking:
 
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We delivered the K5 over to the exhaust guy today. No need to trailer, so I followed Larry over there. It's a out in the county so we had a good little drive to get out there. Since the fuel gauge is suspect right now, the first stop was for fuel. 16 gallons in and we hit the highway. I got to get after it a couple of times. It hauls without anywhere close to the amount of throttle needed to get the truck going in the previous form. Duh, of course, right? But the flip side is, just leave it in 5th once you get up to speed and leave it there. Traffic slowed a couple of times and it got down to 25mph and I just rolled on the throttle and accelerated up to speed again. Pretty cool having that much torque on hand. I did get a little more aggressive going down an on-ramp. It's totally fun to drive again. I enjoyed it before, but it was getting to be a drag to just hammer on it like a pissed off teenager to get up to speed, climb a hill, or even drive into a headwind.

No pics or video. I thought about it, but I just was enjoying it too much to take my phone out of my pocket.
 
Rob,

what are you going to do with the old radiator support, headlight buckets, etc... interested in selling them?

Thanks,

Treb
 
Rob,

what are you going to do with the old radiator support, headlight buckets, etc... interested in selling them?

Thanks,

Treb
Starting another project that could use them is probably out of the question right now, so I'm not against selling them.
 
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