GMC / Chevy Project Big Betty, Cummins power in a weekend warrior

[SAVAGE]

Now to tell you about my clutch. When I was going through the engine I noticed I had hairline cracks on the flywheel where the clutch disc rides. With the cracks I learned I had to get it resurfaced or buy a new one. My clutch still had some meat left on it but now I had the perfect excuse to upgreade to a southbend clutch and flywheel. I went with the 13125-OK, this came with a new 13" flywheel (stock is 12.25"), clutch, pressure plate, input bearing, hardware and goodies, all capable of holding 400HP and 800FT.LBS.

Here is the old clutch/flywheel/pressure plate.


And here is the South Bend in the box, and here it is Installed...by a professional.....me.


P.S. This was before the engine was in the truck. Sorry to bounce around.

 

[SAVAGE]

Ok, well I have been pretty busy the last couple weeks but I did make some progress.
I sold some more truck parts and I bought all my paint and primer and stuff. I went with a custom color I had them mix up. Imagine a mix between metallic black and charcoal gray (grey?). I think its gonna look pretty cool.


Ok I have been mainly focusing on my pedal situation. So this was the biggest major PITA ever! Seriously I think that swapping the motor in was the easiest part of this project. Ok I needed the extra pedal from the junkyard for my clutch (i'm converting from a auto). I got the whole brake/clutch assembly which comes with the pedals and the whole huge supporting bracket. Then I took my dash apart to get the steering column out. The new pedal assembly only needed minor modification to work. Where the old bracket bolted through the firewall and to the booster the two top bolts came in from the engine bay and the bottom two where studs on the bracket. The new one from the junkyard all the bolts where studs that stuck through to the firewall. So I got my persuader and knocked the top studs out and it bolted right in. Then I had to drill a 1.26" hole in the firewall for the stock dodge clutch hydraulics I am using. I also had to make a little bracket to bolt it in securely to the firewall because the dodge turn and lock in style only lasted a couple of test pushes.
So here is a view from the engine bay, and the second pic is a view from under the dash. I just welded a nut to the pedal at the height I wanted the pedal to sit and mounted the push rod to that. Pretty simple after the headache of mounting the master cylinder.



And here is the master cylinder resistor. I just tucked the line up behind the windshield wiper motor.


And here is is all done.

 

[SAVAGE]

The origional oil pressure sender that was in the cummins was a two wire. All I had to do was go to napa and get a one wire gm oil pressure sender with 1/4" threads. Note that if you want to do this you will only have about 1/16" clearance from the bottom of the injection pump but it will work. The third picture is the box for the new gm sender that I am using if you need the part #.


Now the temperature sender was almost just as easy. I got a gm sender for my year of gmc truck ('88) and got a adapter to thread it into the cummins block. I think the adapter was 1/2" to 3/4" but dont quote me on that. Kinda funny but both my oil and temp sender part numbers are really 6640! I found that rather convenient .

 

[Bart]

Thanks for the updates. Love the detail of the swap. Someday I may get brave enough to try one of these.

 

[Maverick]

Awesome swap and overall project.

I'm sure you're making mbryson drool. That is his dream tow rig.

 

[SAVAGE]

Ok not much progress but I did get a order in..

I got 4 Rockford Fosgate speakers. Two are the 6.5" R165X3 for the rear cab corners, and the other two are 4" R14X2 for under the dash. I liked these the best because they are Rockfords and only cost $65 shipped. They also have good reviews and include tweeters (3 way speaker).

In other news my wife and I have been looking for a place to live in Salt Lake City this August. Apartments up there are a rip off so we decided to go the cheaper route.

Now we just need to find a rv park where we can park it. We are leaning towards Mountain Shadows, but we are hoping something better will turn up. I'm really hoping someone will turn up with a place we can park and hook up. Sure would be a good way for them to bring in some extra Benjamins.

Anyway if you have something you'll get my hint and send me a message. After putting a down payment on that beast I got more motivation to work on my truck. I added a 4"x4" cross member between the front frame rails to add extra support for the front passenger spring mount because I notched the frame for extra clearance for the A/C compressor.

 

[YROC FAB.]

Its looking good jake. one piece at a time.

congrats on the new home purchase.

 

[SAVAGE]

Hello everyone! Sorry its been so long. I finally have some spare time to get going on the tread again.

Here is what I did for my air intake. I went with a Edelbrock Pro Flo air filter to ensure I got lots of air into the turbo. In the future I might get one of them air filter wraps to help with fine particles but for now its fine. I built this "custom cold air intake" for about $11 from ACE hardware. I got 2' of 4 inch pipe, one 4 inch 90 degree elbow, and one big wide clamp. I ended up only using about 4" of the 2' piece of pipe I bought, but that's why you always buy extra right? I used a die grinder and took off the seams and letters and junk that was raised on the pipe. Then a little black high heat paint and there you have it. A $40.00, 20 minute intake system.


So overall it is functional, fits well and looks cool. Also when you give it the throttle you can hear the turbo whistle the sweet tune of dixie.

 

[SAVAGE]

Mocking up my gooseneck hitch was a bit over my head at first. I had the B&W setup I swiped from the Dodge. However the chevy frame is much too narrow to use the original frame brackets. I was planning on welding it all right to the frame all over the place and building extra crossmembers ect. And good thing I didnt. FYI welding to the frame is a very delicate task. You cant be too hot or too cold. You cant weld vertical or horizontal, only diagonal as it will cause weak areas for the frame to crack. Considering all of this is is almost 100% a very good idea to bolt in a gooseneck hitch with expensive grade 8 bolts. I also had to keep the hitch under 3/4" above the top of the frame as it would hit the bottom of the bed.



So this is what I came up with. I used two pieces of heavy angle iron on each side to sit on top of the frame. Then I notched out the original B&W rails and welded them to the side pieces, careful not to weld across the supporting areas of the rails. Then I used 8, grade 8, 1/2" bolts, with lock washers and lock nuts, and torqued them to around 1,700 ft-lbs.



Overall the design seemed to be very strong. The only thing I would have done different would be to use 1/4" angle iron instead of the 3/16" i used.

 

[SAVAGE]

Here is what I did for exhaust. Ok, I have something to settle. Why the heck is the word exaughst so flippin hard to spell! Seriously, exaghst. Good thing for auto correct because apparently there are some words in this dang language I can never spell, no matter how many times I write it.

I decided on going with 4" from the turbo back. This would provide me with cool sound, and greatly lower my EGTs. I have heard some people say that 5" straights sound deeper, but I still went with 4" because It is able to be found easy at junkyards, which is where I found mine. Plus I didnt want it to look like some of the toolbags driving around with 18" tips on their 400hp trucks. My 4" should give me more than enough air flow all the way up too 450hp. In reality I probabaly would have been fine with 3".



I had to make my down pipe myself. I hate welding exhaust tubing. It feels like using 7018 rod to weld two soda cans together. Anyway I got it all built up nicely. However it came within about one inch of the firewall so I wrapped it all with lavarock header wrap. This also will help with getting EGTs away from the turbo. I then snaked it down the frame, up and over the transfer case and right out the side of the truck. I was planning on having it exit between the cab and rear axle but I ran out of pipe right at the back of the cab so thats what I get for now.



Hey it sounds like a beast, rolls coal, and was practically free.
If I did have lots of money however I would have bought this >>(http://shop.dieseltuff.com/Downpipe-1st-Gen-H1C-HX35-4-Turbo-Downpipe-28911.htm)

 

[SAVAGE]

My dash had quite a few cracks in it from the sun beating on it over the years. I wanted something cheap, and flexible to fill in the cracks. I was going to use bondo but I was afraid of it cracking also. So I used silly cone (silicone). And lots of it.



Then on a few coats of plastidip to cover up all that. I made the gauge pods out of fiberglass and bondo. Pretty easy really.



Here it is all done up. I decided to knock out the holes for the speakers to free up soe extra room for the 4 inchers and add the rockford fosgate grills back on top of the dash. Over all it looks pretty good I think.
Here is a video of the tach working just incase any of you where interested.
[video=youtube;D7mDem-TSmo]https://www.youtube.com/watch?v=D7mDem-TSmo[/video]
Here is a write up of how to do the tach. http://www.4btswaps.com/forum/showt...he-stock-12-valve-CPS-(crank-position-sensor)

 

[mbryson]

Not sure how I missed this but I like

 

[SAVAGE]

For my fuel I used the 2 stock chevy saddle tanks. I do have an extra blazer tank for the rear also for 60+ gallon fuel capacity. But I just stuck with the two tanks because I didnt know how at the time how to weld to a fuel tank (for the outlet/inlet bungs), and also because I cant afford 60 gallons of diesel anyway.
So what I did is ran 3/8" supply hose from the lift pump straight to the big outlet on the fuel sender. I also had to pick up some non-EFI senders because the EFI ones had four outlets and pumps. Then I ran 5/16" for the return straight to the return on the sender. Then I put in a 3 way tee into the return line and ran the extra line from that to a external fuel pump that sucks from the passenger tank. This way I only have to worry about one fuel system, which is all mechanical. The other tank is simply a transfer tank. Then I simply vented the two tanks together at the senders.
I have also decided that my truck is the ultimate doomsday emp proof rig. The only electronics on the motor is the alternator, 3 sensors wires, and one wire to the starter. And I really dont need any of those in an emergency. My fuel shutoff is a choke cable in the dash. I dont even need a battery, if I need to get it started I just need to park on a steep hill and drop the clutch. :greg: Oh and never mind the fact I can mix paint thinner and old gear oil and still drive around.:greg:



Oh and for your enjoyment, heres how a country boy installs transmissions.

 

[SAVAGE]

I case you where wondering why I have become so vauge so quickly its because my phone and my computer both died within a month and I never thought to backup my pictures of the project from one to the other. So if you have any questions or want more details or pictures of something let me know and Ill try to help

Here is how I ended up doing my winkers (blinkers) and park lights. Because the huge gmc lenses had no chance of fitting behind the grille with the intercooler and condenser I used some really bright led lights from napa. I dont need to explain why LEDs are better than regular light bulbs do I?


I wish I had more pictures of my High steer setup. I had to chop up my beautiful new crossmember to make clearance room for the tie rod. I got a 2wd steering box from the junkyard and had to use the pitmann arm from a 83' f-150. I just walked around with a tape measure and calipers till I found one that fit. It had to be 6" from hole center to hole center to clear the crossmember... again. Any way now I have true high steer with the spring less cap conversion. It also came with a knuckle tie in kit to tie the arm into the original steering knuckle. However I just left it for now and just have 2 tie rods on the truck.
These are some serious arms. They are big and heavy, plenty strong for whatever shenanigans I might get into anyway. If your looking into steering stuff check out this company. http://www.fourwheelsupply.net/ Super heavy duty and best of all super cheap!


Also owe a huge shoutout to YROC FAB, YJ_Auzzy and Midstate Jeep Parts for helping me get everything done on the steering.

 

[SAVAGE]

Here's how to do a 2 day paint job. First day prep and body work.



That evening, sling some primer.


Next night, spray paint like a boss.


Good thing my buddies helped me out so much on this or it would have never gotten done.

 

[SAVAGE]

Heres what she looked like right after paint.



Still needed taillights, hole in the bed for the hitch, toolbox ect.

 

[SAVAGE]

Took her out for a nice little test drive. Everything works awesome. Locker, posi, and even my twin stick transfer case!:greg:


Decided better see if she can walk the walk so we towed the tent around the valley.


And here we are for the big moving day. All of our belongings loaded into one trailer.


Made it safe and sound. The truck pulled like a horse with 3 left nuts all 140 miles. I even averaged 12 mpg dragging that 18,000 lb trailer! :greg:

 

[SAVAGE]

So my wife and I decided to take a drive over the moutain and my damn tire decided the altitude and heat were too much to handle.



Well I beat out most of it with my 6lb sledge but It is what it is. Ended up being cheaper to pick up a used set of tires off KSL.


Here is how the black beauty sits right now. Cant complain she's pretty sweet.


In a few more miles Ill be past the break in period for my clutch and I can finally take that stock fuel plate out.

 

[Bart]

Great work on the truck. I love what you ended up with.

 

[XJEEPER]

Sweet build, love the wit as well. Say "gazast"......much easier to spell too!