Cummins 12 Valve swap

[j_cst_10]

I recently purchased a 1990 Dodge ram 1 ton with a cummins 12 valve and getrag 5spd manual for $2,600 with only 120K miles on the truck!

So what better than to swap the drive train into my 70 CST/10. The dodge has already had some injector pump work and probably puts down 250-300RWHP and around 600-650 ft-lbs. The dodge really moves.

Has anyone done a performance C10 build with a cummins 12 valve?

[bucketObolts]

check the 67-72 truck build thread someone is doing one. What are you gonna do with the rest of the truck? looks like a clean 1st gen. to me. With 120k miles, that would go for around 5-6 grand here. Trust me, I have 3 Cummins Duallys

[j_cst_10]

I was going to sell the truck as a complete roller minus engine/transmission and radiator. The bed, floors, front clip are all rust free with a straight tailgate. Nice interior too.

[5150.4.67]

They are stump pullers for sure. Make sure you put an overdrive in it......

[pulltilbroke]

The Getrag already has a .77 overdrive in it.

That does look like a clean 1stgen though, does it have the usual roof rust right above the windshield?

I will tell you that 12bolt wont be happy with a 12v in front of it though.

[1972K20]

If I was going to do a Cummins swap into one of our trucks, I would at least start with a 3/4 ton truck or better. I just don't think it would be a good idea in a half-ton.

[Bob B.]

If you are asking for opinions, I would not do this swap. You have a nice Dodge there that is worth something as it sets. Sticking that Cummins in a C-10 is going to require major modifications. You will have to cut the firewall and front crossmember. Your 1/2 ton front suspension is not going to handle the extra weight of a B series Cummins. The gearing in your truck will be wrong, so you will have to swap rear axles or install some type of overdrive. Your 1/2 ton 12 bolt Corp. axle will not hold up to the torque of a Cummins either. Nor will the driveshaft. In short, you will end up with a roller Dodge, worth maybe a grand or two, and a freak C-10 that won't be worth much either. If you really have to have a diesel in that C-10, go with a GM 6.2L or 6.5L. It is an easy swap that will not require butchering up the truck, and those GM diesels work well with the stock gearing. They will not tear the truck up. That's just my 2 cents.......

[Big J]

Its been done, doesn't look like too big of a deal to do. Knock it out man, I would if I had one.
http://67-72chevytrucks.com/vboard/s...hlight=cummins

Go to the projects and build section and type cummins in the search this forum window. Looks like there are several cummins builds going on.

[pulltilbroke]

Bob B. makes a few good points but is wrong on a few things. I imagine your C10 probly has either a 3.73 or 3.07 rear gear which would work excellent with the 12v/Getrag combo. another point is the Getrag ALREADY HAS AN OVERDRIVE OF .77 Another point is that you wont have to butcher the firewall or crossmember if you get the engine placement correct although it will be kinda tricky to get big exhaust tucked between the heaterbox, frame and block.

If you do do this swap the 12 will have to be beefed up considerably and you'll have to get a new drive shaft made with at the very least 1350 joints. Theres a reason Dodge used 1410s in there Cummins trucks.

I have done my homework on this swap because I am planning a similar one in my 67 C20.

[Maxxd07]

Horrible idea, you should just sell the dodge to me for $2800.









I would say to go with a 3/4 ton pickup or swap your body onto the dodge frame and make a custom dually bed.

[69 Camper CST]

Hmmm,

Not to disagree with Bob, but I love the 12 valve Cummins. I swapped a 96 P Pump into an 87 Ramcharger. It is a blast that gets great gas mileage... 26 mpg is my best to date and that was cruising at 70-75.

I don't think you would have to cut the firewall as the Chevy's seem to have quite a bit of room and if i can fit a cummins and 2nd gen intercooler where a 360 V8 sat you should be able to do the same, or at least get close, may take some rad support mods.

As long as you get heavier front springs, good bearings and don't tow with it the rear end should last a little while. If you start to tow, I agree the torque will eat it up in a hurry.

I will agree, you got a screaming deal on the dodge and you may be able to put some money in your pocket and pay for a different engine swap... if you want.

[Bob B.]

In all fairness, many times I have seen this swap done it resulted in a mess. Of course, it might have been the knuckleheads that did the swaps too! If you are going to use the Getrag (I hope there's nothing wrong with it!) the ratios would be O.K. with a 3.07, as the other post states. But then again, what fun would the Cummins be if you can't drop the hammer on it once in a while because you are scared to break something? If you could get the Cummins without cutting the firewall (I believe what the others are saying) and the heater box is in the way of the exhaust, you could always use one of the aftermarket HVAC units that locates on the cab side of the firewall. Anyway, good luck whatever you decide to do.

[j_cst_10]

Opinions are like a%$holes, everyone has one right?

Just kidding, but it's going to happen. I was just wondering if anyone did a performance build. Thanks for the support on the swap.

And yes, the drip rail is starting to go, not sure if the windshield in messed up yet or not though.

[haulnrat]

Just Do It!

Different is good.

I have thought about swaping one in my 'burb to make it a real tow machine.

Putting 3/4 ton suspension and rear end would probably be a good idea.

[Beat68CST]

Originally Posted by haulnrat

Just Do It!

Different is good.

I have thought about swaping one in my 'burb to make it a real tow machine.

Putting 3/4 ton suspension and rear end would probably be a good idea.

That is the perfect idear.

[5150.4.67]

You might think about a NV4500. The Getrags had alot of trouble holding up to the 6bt's power. .73 on the over-drive, if memory serves.
My .02.
J

[rideharder]

only cause its bad ass i vote DO IT!!!! im curently mid way on my cst 10 with a auto and some soon to be power. the motor fits in there with out mods.... but he turbo is where the heater should be and the rad/ IC is a problem heres my build hope it helps ya tear that dodge up
oviously im building it how i want... the consol does not have to be that big nore the truck sit that low
http://67-72chevytrucks.com/vboard/s...d.php?t=450698

[pulltilbroke]

Originally Posted by 5150.4.67

You might think about a NV4500. The Getrags had alot of trouble holding up to the 6bt's power. .73 on the over-drive, if memory serves.
My .02.
J

The reason the Getrag got a bad rap was because a batch of em came out of the factory setup to tight(to much bearing preload) and with the Getrag your bearing preload is critical. Yes the Getrag G360 does have some smallish countershaft bearing and couter shaft but if you take care of them they will provide many years of trouble free service. You have to keep good clean fluid in them, make sure they don't leak and over fill them by 1 qt. I use Mobil1 5w30 full synthetic in my old mans Rag, but there are other good fluids you can use in them also. Don't run 80/90 in em cause its to thick and cant get up to the bearings in the top end of the tranny. You also want to make sure the pilot bearing/bushing is in good shape also other wise you run the risk of destroying the input and cluster gear.

I rebuilt the Rag in the old mans truck a while back and have had absolutly no trouble with it since even towing heavy with it on a regular basis(21,500), I also addresed all the issues I mentioned at that time.








21,500 gross



In other words take care of the Getrag and it will take care of you. I don't think you'll have much to worry about with a truck as light as yours.

[j_cst_10]

Yeah I am getting excited to start the project. I really want to push the stock injection pump, lifters and turbo to get as much hp and torque for the least amount of money. I have done some work already to it, and the power is significantly over stock. It is nice to have the larger factory injectors that came on the 1st gen cummins.

Plans call to intercool it soon and upgrade the stock lift pump. I am having a blast tooling around in the duellly though.

[pulltilbroke]

BEFORE you turn any screws or tamper with the pump put a set of guages in it first. Pyrometer, fuel pressure and boost

[j_cst_10]

Well you are a day late and a dollar short, I've already done all of the pump tuning.

I am putting the gauges in this weekend though. I've been easy on it so far and I have a modified air intake and exhaust to help it from getting nice and toasty in there.

[SchreinerM]

Any new details on this swap?

[Dieselwrencher]

This will be a cool build! I wouldn't bat an eye at dumping a 12v in a 5 lug half tonner. The frame could use some boxing if you're going for big power, but for under 400hp I'd think you'd be fine. If my Vette front end can take it, the truck will too.

[502ms]

I already did it. Just sold it. It fits. The only thing you need to do is upgrade your suspension of course, rear end, driveshaft and rear suspension. The crossmember from the 1st gen can be utilized and you just route the down pipe as you need nea r the firewall and you are golden.

http://leonmillette.photoshelter.com...007l6PaIxsP54/
Password - turbo
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[502ms]

Oh, run a slimmer radiator, electric fans, and gauges. It is a beautiful sound coming from the Chevy.
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