CK5
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1991 Volcano K5 - Family Wheeler - Fully Independent Twin Turbo BBC

But.... 36" of travel would be more better.
In a way, but I'm not making it trophy truck width, just stock width. I might be able to squeeze almost 20" out of the rear travel. The limiter will be the width, and the CV angle from RCV, because in order to get more travel with the CV, I would need to either make the truck a lot wider and/or get a narrower diff like those $15K pumpkins from Fortin where the CV flange can be inside the diff.

I don't think either of those are necessary for me, 16 - 20" of travel without all the unsprung weight of solid axles will work very well for what I want do to. I already have most of the parts to build the center diffs, but I want to get it running as is first, plus I have some more customer projects.

This will still have a back seat for the kids and be about stock width, like the K10 was, I want the body to appear kind of factory while not being factory with the way it works, plus ~1500 HP on pump gasoline will also wake it up.
 
Update on this...I have been collecting parts for this for a while now obviously.

I sold my K10 as is, with the EFI 489 BBC, coil-over Dana 60, etc. I decided time is money to take it all apart and rebuild the K10 just to sell, and I would start over. Went to a good home, guy plans to do light trails and dunes and maybe give it a new paint job. He has a 10 year old son that was very excited.

Now I don't have a running square to drive currently.

Here are my long term plans at this point.

I have a 4L80E I will build for the K5 to go behind a Twin Turbo Big Block, either a 540 or a 572 I will build.

Behind that will be a drivers drop NP205 that I bought I will rebuild with 35 spline outputs I have.

Then at each end will be Aluminum 9" Independent center sections, they are only about 13" wide and I will use them to build a completely custom tube chassis with fully independent front and rear suspension. Double A arm in the front and 5 link in the rear. Not stock at all, I am planning at least 16" or more of wheel travel with nice coilovers and air bumps. I have collected many of these parts already.

This will be light weight and also strong and fast. Will be great for dunes, dirt drags, sand drags, etc.

However, as busy as I am this is going to take time, quite a bit.

So in the meantime I have a complete K5 now, you may recognize, I will just swap in my old 388 I built about 3 decades ago, along with a 4L60E, and have a K5 I can use in the meantime while I build the different parts of it in the next few years. The 85 will be used for a different project, it's very solid but not very close to driving as is.

1st up, get it running...388 SBC, 4L60E, stock NP241, stock axles, 33" tires

Next year I hope to put a cage in the cab, a soft top, etc. I still haven't decided if I will leave it as is or go full vert.

After that I will build the fully independent tube chassis and twin turbo BBC to swap under it.

K5 on the lift ready for action....this first step will be mostly parts I already have to get it running.

1991 K5 previously owned by @longbedder....



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388 SBC I built in 1996, check...(been sitting in a barn for 8 years after I beat the snot out of it for over 20 years)

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More to come in the next couple weeks as I catch up...
So you're trying to get all our California trucks out there.
I am happy that @longbedder 's truck went to you
 
So you're trying to get all our California trucks out there.
I am happy that @longbedder 's truck went to you

Yes we like rust free trucks, they are hard to find here! There are still plans for the 85 I got from you, it will not be abandoned. After buying my K10 in San Antonio 22 years ago and loosening the body mount bolts with only a ratchet I never wanted to start with another midwest truck again, and I never drove it in the salt either.
 
We have rust and road salt here but I still do a little internal giggle when I see an older truck or car here that isn’t just rotted out trash.
 
So I cleaned the engine up, gave it some fresh paint, and of course since I specialize in intakes and EFI I can't leave the carb I built 20 years ago on there. And since I have a dominator EFI system I purchased for the future BBC build, I just need a different intake and fuel rails to work for now.

So I swapped intake and this ole engine is still pretty clean inside, shows what regular oil changes do with good oil. This engine is special to me because it was the 3rd V8 I ever built, but the 1st one I ever built that was mine and by myself. The 1st two I built with my father and they were his, a 468 BBC and a 412 SBC.

I built the 388 SBC in 1996, it's a .060 over 4 bolt 350 block, an actual stock 400 crank with the mains turned down (this was before all the 383 kits were readily available), stock 350 rods, and KB hypereutectic pistons. It has a retro fit hydraulic roller cam, and I bought used World "Sportsman II" iron heads that were previously ported that came with the used Harland Sharp roller rockers.

Specs on the cam were 234/[email protected], .540"/.560" lift, 110 LSA on a 106 ICL, you never forget your first cam.

This engine has been raced and beat on, sprayed nitrous countless times, and it doesn't owe me anything, if it goes now I definitely got my use out of it. It was in the Regal in the pic earlier for over 20 years, went 11.8@115 NA and 10.4@129 on nitrous with pump gas. The K5 is quite a bit heavier so it won't be that fast, but it will be more fun than a wounded stock TBI until I can get the BBC built.

And of course it needs a Volcano, can't leave HP on the table.

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There was some casting flash on the Holley intake I cleaned up, I also did a mild 1205 gasket match, even though the heads are closer to 1206. I need to resell this intake(as used of course) when done, I think its more versatile with the 1205 port.

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And since I am using the dominator EFI, I have trans control already there. So instead of trying to mess with the governor on the 700R4 to change the shift point from teh stock TBI shift point to around 6200, but not wanting to get new driveshafts and input shaft and such for a 4L80E that wouldnt work later, I bought a 99 4L60E out of a burb, had 170k on it for $100, fluid is nice and pink. It will bolt right in. So then I put a Transgo shift kit in it to help it live and a 2800 stall converter. Along with a new filter. So yes I dropped nearly $1000 on a $100 trans just to use temporarily....:yikes:

I figured it had a slim chance stock, and a decent chance with a kit.

I'll definitely use a larger trans cooler as well.

You think it will live for a couple years? We'll see.....

Pictures during disassembly, if you want more look at the Transgo 4L60E Pro Kit install instructions. I did not take the pump out and do internal mods, figured if I went that far I would be rebuilding it.

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Dang! What kind of trail were you running?

Does that thing have actual good motor mounts?
 
I found one, got it ready then plopped it in with the 4L60E and FTI converter.

Installed the poly inserts, old motor mounts were no bueno.

Blasted and painted the engine mount uppers and steering brace, they were raw steel! That wouldn't work around here.... ha ha

I put a new aluminum reverse rotation water pump on and etched my logo in the fuel rails since I have a Volcano insert in there.

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Found some more parts to put on, anything I remove my attention to detail just won't let me put it back on if its all filthy or raw steel, even if it's temporary.

Got a new powermaster 140A alternator coming that should work on the BBC install later too. The idler pulleys felt good but the alternator bearings didn't sound the best.

Bead blasted the cast aluminum accessory brackets..

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I like GM design on the little press in removable inserts that allow double shear with casting tolerances...

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Also added factory your hooks I bought from @kennyw and blasted and painted...

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Chipping away, the cooling system I upgraded so it's ready for a twin turbo big block.

Its a 34" wide diesel width core, but its dual 1.25" aluminum, which is equivalent to a 5 core brass radiator. It uses the wide mounts, 6" wider than a big block radiator.

Because its so wide, it allows dual 16" genuine SPAL fans, for over 5000 true CFM.

I worked with @mrk5, he made the fan shroud to my specs with his CNC router and finger brake.

I also installed the 150A alternator and blasted and painted the battery tray and added a new battery clamp with a new Deka AGM battery.

I have changed the input and both output seals on the Tcase, and the converter seal on the trans before I installed them.

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That's a nice looking radiator, it looks like it fits the factory hold down brackets good. My current diesel radiator is good (knocks on wood) but I've been worried about what to do when I eventually need to replace it, that looks like a great mostly direct replacement option.
 
That's a nice looking radiator, it looks like it fits the factory hold down brackets good. My current diesel radiator is good (knocks on wood) but I've been worried about what to do when I eventually need to replace it, that looks like a great mostly direct replacement option.
I agree, this is why I have the same setup on the way. :haha:
 
We may start selling the setup as it is the largest possible cooling option you can fit without major modifications.

The radiator is a Cold Case unit, I wish it was made in the USA but I could not find a US made unit that is that large and has dual 1.25 " tubes instead of just single or dual 1" tubes.
 
Starting a list to cross off as I post pics and also realize the list isn't complete and it will grow...

install converter bolts
install Tcase brace
install transmission dipstick

cut and TIG weld headers for 3" collector
TIG 02 bung
install headers
install starter
swap fuel pump for Walbro
install adj fuel bypass pressure regulator
plumb fuel system
flush heater core
heater hoses
radiator hoses
install transmission cooler
plumb transmission cooler
add coolant
add transmission fluid
add Tcase fluid
build dual 3" exhaust
remove factory TBI wiring and ECU
reprime oil system
install distributor
install 8 coils
install dominator ECU
install relay box (6 relays for both fans, fuel pump, coils, low beams, high beams)
make new starter cables
wire EFI
wire fans
wire fuel pump
write and install custom 388 DIS SBC/4L60E tune
bring engine back to life

I started to swap the fuel pump, but realized pretty quick, the original tank smells like kerosene and is all gummed up inside and the factory float is broken off and sitting in the bottom. Luckily I had been collecting parts and had a brand new tank and sending unit sitting there to put the Walbro pump into....

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I'm contemplating installing the Dual 450 Walbro setup I have sitting there instead, that was good for a twin turbo BBC, but even just running one of the pumps is overkill for a little pump gas 388.

This 255 Walbro in the stock sender is more than enough, but it's only temporary.

I don't want a fuel cell in the K5, at least not in the cab, I want it to fill just like a stock K5.

I'd have to cut the factory hole bigger to go dual pumps, and then add a sending unit, I have a Holley LiDAR floatless sending unit sitting there too.

I'm just thinking it might be easier to do that now when the tank is still new and dry.

I'll see what plumbing I have here. Don't remember if I bought the fuel plumbing for the K10s 489 with a 100 shot or a 572 with twin turbos....:coolblue:
 
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