67 C-30 Dually pickup build.

[DBear]

Originally Posted by 67_C-30

Thanks!

I'm using the original in-cab tank with a sending unit from a '71 - '72 model truck that has the return line. I'm assuming that's all you'd need for your Suburban as well.

On the mounts, I'm talking about the towers that mount to the frame. You can use SBC motor mounts, but you have to get BBC towers.

thanks for the feedback....I have been looking for that sending unit 71-72 with a return line for a blazer/suburban and none have the extra outlet for return line. Am I looking for the wrong thing?

[*Dylan]

Engine sounds solid! Now where are the burnout videos? Have you picked up the fenders yet?

[67_C-30]

A little more progress...

Anybody familar with 6.2 diesels know the factory V belts set-ups can be on these trucks, so I decided to try something a little different. I know I could have gone with a serpentine set-up and eliminated the problem, but I couldn't find any in the local boneyards, and honestly I actually wanted the look of V belts on this old school dually (as crazy as that probably sounds). I decided to modify a hummer 4 groove set-up so I can run 2 equal length belts to the hydroboost pump, and 2 equal length belts to the alternator. Dual equal length belts usually do much better than single or dual different length (meaning where one runs over different pulleys like an A/C belt does on some of them) set-ups in my experience. We'll see how it holds up. I had to space out the pump and the alternator, but I used this as opportunity to put a stainless 1" X 1/8" washer that I made to put behind and in front the hydroboost pump bracket that bolts to the water pump. The brackets always get distorted, and elongated trying to keep it tight, so the big washer will sandwich the bracket and hopefully help keep it tight by having a bigger clamping area. I also have a dual pulley that I'm going to put on the new alternator, but I didn't get to that today.

The Hummer crank pulley is fine to use as, but I had to modify the water pump pulley. It had a raised boss to mount the clutch for the fan on the Hummers. I machined the boss off, and bored a 1.583" X .250" counterbore to help locate the fan. The locating pin on the water pump catches the fan with this thicker pulley, but its only about an 1/8", so I wanted a little more security. The hub on the fan is 1.580" so I gave it a .003" slip fit and it has no detectable play or slop. I bolted it on with M8 X 1.25 X 30mm bolts. Heres some pics of it. It really looks cool on the engine IMO with all those V grooves!

I also got the power steering box mounted today also, and I'm going to try to get the hydroboost system modified and installed tomorrow.

[capev86]

even with a 4.10, you won't be able to get that diesel going to fast without an overdrive. you can get a hopped up 6 speed now with a .7 5th gear and .52 6th. with the original 5.13 that would be the same as a 3.73 with a 700r4 in top gear. the 14 bolt is a nice, but you can get a 4.10 gear for the ho52/72 as well. i'd only bother with a 14 bolt if i was trying to get something softer which would be better with that diesel anyway.

[67_C-30]

Originally Posted by capev86

even with a 4.10, you won't be able to get that diesel going to fast without an overdrive. you can get a hopped up 6 speed now with a .7 5th gear and .52 6th. with the original 5.13 that would be the same as a 3.73 with a 700r4 in top gear. the 14 bolt is a nice, but you can get a 4.10 gear for the ho52/72 as well. i'd only bother with a 14 bolt if i was trying to get something softer which would be better with that diesel anyway.

I put a 14 bolt in the truck and changed the gears to 3.21's. The 3.21's work very well the close ratio NP435 that I'm using. The NP435 is not really a granny 4 speed like the SM420/SM465. It has a much higher useable first gear (4.56) unlike the 7.05/6.68 geared Muncies do. This set up was as close to a OD trans as I could get. Even with high gearing, the truck will still pull as well as 4L80E truck with 4.10's (which was the most popular set up from the factory with 6.2/6.5TD diesel trucks) , and still have a pretty good highway rpm range. I'll be able to run 70 mph at 2400, which isn't too bad. Here's the comparisons between my set-up and a 4L80E truck with the standard 4.10's:

[GruntMoanCough]

Great job! Watching this with interest.

[67_C-30]

Thanks! I truly can't wait to have it all put back together.

[mal68ibu]

The hydroboost on my truck had two bolts line up perfectly (I pulled my hydro from an 89 burb), I drilled out the other two bolts on the bracket and left bolt #5 and #6 off. It works awsome but I still have the stock narrow 70 and older rear brake line so my rear brakes come on to early and strong. I need to replace it with a larger diameter 71-72 style brake line, so that the pressure to the rear brakes does not built so quickly.

[mal68ibu]

Where did you get your 3.21's? Junk yard or new? I've been thinking about this. Since I have the gear splitter it does under and over drive. So I'll have a 20% increase or decrease in transmission speed with this unit. I figured I can use the 3.21's and under drive them to turn them into 3.85's, or over drive them and make them 2.57's. I currently have 3.55's (4.26 and 2.84).

[67_C-30]

Originally Posted by mal68ibu

Where did you get your 3.21's? Junk yard or new? I've been thinking about this. Since I have the gear splitter it does under and over drive. So I'll have a 20% increase or decrease in transmission speed with this unit. I figured I can use the 3.21's and under drive them to turn them into 3.85's, or over drive them and make them 2.57's. I currently have 3.55's (4.26 and 2.84).

They are new Yukon gears for the 14 bolt I put in my truck. If you are running a Dana 60, I'm pretty sure the highest gearset for them is a 3.31, which is pretty much the same.

[67_C-30]

Originally Posted by mal68ibu

The hydroboost on my truck had two bolts line up perfectly (I pulled my hydro from an 89 burb), I drilled out the other two bolts on the bracket and left bolt #5 and #6 off. It works awsome but I still have the stock narrow 70 and older rear brake line so my rear brakes come on to early and strong. I need to replace it with a larger diameter 71-72 style brake line, so that the pressure to the rear brakes does not built so quickly.

Thanks for the info. I actually started on mine today, but I didn't finish it. Did you have to lengthen/shorten the rod, or were you able to use it as is?

I moved the truck to the front earlier so I could work on it and watch the kids play. I got ready to put it back up, and the battery wasn't strong enough to crank it (alternator is wired yet) , so I used the '69 SS as battery charger. I had washed it earlier, so it was already over there.

[67_C-30]

Purdy! I had some left over POR-15, so I coated the power steering box with it. It still looks wet!

[mal68ibu]

On the hydroboost, instead of lengthening my rod, I pulled it as far out as it would go with the master on it, pulled my brake pedal all the way forward, and marked my pedal. Welded a piece of flat steel to the back of the pedal. Took some more measurements and drilled a hole for the bolt. Here I just went out and took this picture.

[67_C-30]

Originally Posted by mal68ibu

On the hydroboost, instead of lengthening my rod, I pulled it as far out as it would go with the master on it, pulled my brake pedal all the way forward, and marked my pedal. Welded a piece of flat steel to the back of the pedal. Took some more measurements and drilled a hole for the bolt. Here I just went out and took this picture.

Thanks for the pic. That's a good idea!

[67_C-30]

I got my hydroboost modified and mounted. There's nothing like taking a new (well reman) part out of the box and breaking out the cut off wheel and drill press on it.

I got the master cylinder mounted, and brake lines run also.

[bigguy69]

looks good!! i really like the way this truck is turning out!

[67_C-30]

Originally Posted by bigguy69

looks good!! i really like the way this truck is turning out!

Thanks! I'm VERY busy time of year owning a swimming pool business, but I am determined to get it going, so I just keep chipping away at it. Sometimes I can only spend 15 or 20 mins a day on it, but I have been doing SOMETHING to it everyday. I got home in enough time this evening to run the hoses for the hydroboost system.

[mal68ibu]

What are you running for brakes and master cyl?

[67_C-30]

Originally Posted by mal68ibu

What are you running for brakes and master cyl?

The hydroboost is off of a G30 1 ton bus, so I just got a new master cylinder for it. I have disc brake spindles off of a '72 C-30 on the front, and the rear (14 bolt from a '97 C3500) has big massive drums.

[mal68ibu]

If you haven't yet I would advise replacing the brake line to the rear of the truck with the 1971 and later larger diameter line. I didn't do that and my brake bias is to the rear quite heavily. I have a willwood adjustable prop valve and its turned as far to the front as I can. The truck is drivable but I definatly need to be on my toes.

[67_C-30]

Well, after making some real good progress on the truck over the last several months, I have ran into another another big snag. Our house burned last Tuesday, so I am living in an apartment while they rebuild our house. I'm thankful we weren't there, and I'm glad we had insurance, but the whole situation just plain sucks! The fire started in my computer room, which happens to be the room I kept many of my new car/truck parts, my guitars, my model car and card collection from my childhood. We lost many pictures, along with all of our clothes, and the kid's toys because of the heat and smoke. I won't be able to work on anything here, obviously, so all of my projects are on hold. This going to be a LOOONGGG several of months for me!

[Palf70Step]

Glad you are alright and a real bummer about the house. Hope the house rebuild goes quickly and uneventfully for you!

[GruntMoanCough]

Sorry to hear about the fire, 'least you're all OK. Good luck gettin' it back together.

[OLDIRON69]

Just a good thing you guys were not there. Good luck on everything!

[67_C-30]

Originally Posted by Palf70Step

Glad you are alright and a real bummer about the house. Hope the house rebuild goes quickly and uneventfully for you!

Originally Posted by GruntMoanCough

Sorry to hear about the fire, 'least you're all OK. Good luck gettin' it back together.

Just a good thing you guys were not there. Good luck on everything!

Thanks guys. It is coming along. They have all the walls torn out and are just starting on rebuilding the house.