New member needing advice on repower

[RoadGoesOnForever]

Hello all. I got an 82 K5 Blazer that Ive had for 2 years with the anemic 6. 2 NA motor. I have decided to switch it out for a Cummins 6BT motor. Ill be using an NV4500 which I will mate to an NP205. Have any of you guys done this swap. If so, can you lead me to a place to get the parts and info I might need.

 

[Power Wagon]

It's too heavy. Dont' bother.



The 5. 9 weighs a LOT more than the 6. 2, and if you put it in there, the blazer will be so nose heavy and overweight for the axles and tires it won't be safe to drive.



Try looking for a Cummins 6A engine.

 

[RoadGoesOnForever]

Uh, with all due respect I think you need to research this a little more. The 6. 2 only weighs about 250 pounds less at the most. I have a push bumper off of a wrecker on the front of my truck right now that weighs over 200 easily and I can sit on it ( I weight 220 ) and the truck doesnt droop more than half an inch. This is a K5 Blazer not an S10 Blazer. I also have very stiff lift springs in the front to compensate for any added weight.

 

[Matt S]

I'm not sure how much a 6. 2 weighs but a 5. 9 weighs around 1000-1100 lbs. What I think Power Wagon is getting at is the weight would be WAY more than the front axle can handle. Not the springs. Dodge didn't recommend snow plows on trucks because the front axle would be overweight. That is a 4500 lb Dana 60. Not a 10-bolt. That is all. You may need to upgrade the axles in your swap.

 

[RoadGoesOnForever]

Are you sure its not because of the springs. After all, your rigs have coil springs which are more prone to sagging with more weight on the front than leaf springs. Ive seen people with big blocks and very heavy front winch bumpers in K5s and not one has broken an axle tube or any other part of the axle because of too much weight. But I do plan on putting a Chevy Dana 60 in just to handle the power, so the axle will not be an issue. By the way, how do these guys with Ford 2wd vans and trucks get away with it. Do you think that the twin I beam is any stronger than a solid front axle, I dont think so.

 

[bvanetten]

You probably have a Dana 44 up front and that just won't cut it. Also, a full size blazer has a rather short wheel base which might give you problems with driveline angles. This is why... To stick a 6bt in and have it fit right you have to move it all the way back to the firewall. The back valve cover will be a 1/4 in. or less away from the firewall and this will only give you about an inch of space between your fan clutch and radiator. Moving the motor this far back moves the whole drive train back causing potential driveline angle issues on a stock ride height let alone a lifted truck. Does your blazer have a lift? Obviously this isn't an issue on a suburban or a lwb truck. I know allot of jeep fab shops use custom extreme angle CV joints on their drive shafts for lifted jeeps. Will they put up with a Cummins or grenade? I only have experience with autos, and they are longer so maybe this isn't an issue. How about your rear axle. It better be a 14 bolt. 73 to 87 Chevy trucks are known for having frame cracking problems where the steering box bolts up. You would be time and money ahead if you checked that and boxed the frame from the firewall to the frame horns and built your own engine cross member. I don't mean to rain on your parade... I'm a conversion nut myself! But their is allot of research you need to do to stick a 6bt in. Have you thought about a 3. 9bt? It would fit quite nicely, isn't as heavy, and uses the p7100 pump. I've heard of them being bombed to over 500 ft. lbs. Not bad out of a 4 banger! Plus you should be able to find one with a t400 transmission, Chevy adapter plate, and already balanced for automotive use for under $3000.



Keep us posted



Bruce

 

[EOliver]

It's not the springs that are the problem. You can always call up a custom spring manufacturer with the weight and they can build springs for your application. The axle is what we are getting at, it needs to be upgraded. I see you will be swapping to a D-60, which is good and will most likely have a weight rating of 4500#. It doesn't take much to get to that with a Cummins, NV4500, and NP205 all together weighing in at around 1600# or so. That will leave around 2900# left and you still have almost 4000# of rig to sit on there. All in all, you will need the D-60 just for the weight carrying capacity, as you will probably be near the limit of the front axle before winches, bumpers, or snow plows.



It can be done, we are here to help.



Eric O.

 

[RoadGoesOnForever]

OK, perhaps I should have given you guys some more background on my truck and the extent of my research and knowledge. Its an 82 K5 Blazer with 4" of lift (will be 8" by the time the Cummins goes in. It has a 14 bolt ff rear axle, an SM 465 transmission (will be an NV4500 with the swap), NP205 transfer case, and 8 lug 10 bolt front axle. I have Rough Country springs on the front (highest spring rate of any manufacturer) and a shackle flip in the rear. At the time of the swap I will be adding a rear CV jointed shaft with 1350 series u joints ( will take care of driveline angles and power output of motor). Ive already talked briefly to Randy Bleuth at Reliable Diesel in Arizona and he will sell me conversion motor mounts and he also briefly explained that the motor will easily fit with a change in front crossmembers and very minor reworking of a small part of the firewall area. I will also be boxing in the frame at key locations to take care of frame flex from the motors torque. I already have a steering brace to take care of the infamous frame cracking by the steering box. I will also be putting in a D60 front end to handle the power of the Cummins. The main problem right now is money. Ive got two more years of college left and money will be tight for a while. Again, thanks for all your advice guys, but I will definitely be putting in a 5. 9 Cummins. Now, has anyone on this site done this so I can get through all the little details as I go along.

 

[bvanetten]

Ahhh! You have spoken with Randy! Well, that's a different story! I stop buy and pick his brain on a regular basis. Good guy, knows his business. I'm writing his web page as we speak. I've seen a few of his Chevy conversions and yes, the 6bt will fit, a bit tight, but will fit. What R&P will your diffs have in them? What size tires? Why are you putting an 8" lift on it?!?!?



I have to disagree with you on the coil vs. leaf. Coils are by far a better type on suspension. I wish I had them. As to their weight carrying ability... I own a unimog, it has coil all the way around and is rated for 4000 lbs is the bed. No sagging, rides smooth, tons of wheel travel and it is one of the smaller models. You should see the BIG diesels. They have coils also.



Bruce

 

[RoadGoesOnForever]

I have a 410 gear and right now 35" tires. I will have 38"s by then with the same gear ratio. I may go with a 6" lift instead of 8". Ive done some massive cutting of my fenders to fit bigger tires, I just need maybe 2 more inches of lift to fit 38s. I go rockcrawling and trailrunning quite regularly, that is the reason for the lift.