1990 K5 Blazer -- 4 cyl Cummins

[Overdrive]

1980 would still have had the more squared-off, higher hood. This one has the hood/front end that slopes down a bit which came along in 1988.

 

[DarinM]

Yeah - true. What's throwing me is the grill/headlights. But I'm not real familiar with the K5s.

 

[dieselcruiserhead]

Wait until you actually are around one. A conversation with the hood up is impossible. Inside, you will be borderline yelling at your passenger and everything will shake. Sounds cool but you, like many who have done these conversions, will change your mind. You can not change the fact that this motor was never intended to be in anything smaller than a step van.

I would say none of this is particularly true. This stuff really makes me quite upset because it also hurts the resale and value of our vehicles that are probably outfitted with probably the most impressive and reliable, and bone simple diesel engine produced through the late 80s and early 90s with the performance characteristics of a EFI engine, but that can but run with a 12 volt battery for days at a time, if your alternator were to go out.

They are about as loud as a 1991 first gen Cummins and they rattle a little more but the factory motor mounts were designed to address this. I have installed one, have many friends who run them, and several of us are on our second or third installation of them. I will say they are loud, they are 700-800 lbs (about 200-300 lbs heavier than a V8). It takes only a mildly intelligent approach to have good vibration characteristics (aka, use real motor mounts, not suspension leaf bushings like they do with a lot of performance V8s).

Those who attended the diesel course at Overland Expo may recall as I started and idled and throttled this 4BT-powered Rover to address some of these misconceptions.

If they are really loud at idle it is because they have been tuned this way (to have killer torque off idle). They can be easily tuned for noise reduction at idle which is one of the four fueling adjustments on the fuel pump, like like a Rover 300TDI or any other diesel with a Bosch VE pump (which is probably 90% of 4 and 6 cyl diesels through the 80s and early 90s). This is the only particular point that can be bothersome.

It is also has gobs of power, but in particular jobs of torque. Mine would fly up the passes here in Utah at 75 in 5th with 35" tires and get 23-25 mpg on average.

I am on the installation of my second one. I would say it is a little loud and uncomfortable for a family vehicle but this is the ultimate expedition engine.

I hope it helps.

 

[Rovertrader]

good time to ask this question I suppose- I have access to a 4BT in a bread truck, and a 24 valve 6BT missing the turbo and injection pump for $3k for the pair. No idea on condition- supposedly the 4BT was running when parked. My thoughts are even if both get rebuilt, not a bad deal. Thoughts?? Thanks

 

[dieselcruiserhead]

Sure, probably.

The 24 valve would be hard to fit into something, it is a massive engine but has value particularly rebuilt. The best place I've found is a company called Tennessee Diesel Conversions 865 809 7402 that is an authorized Cummins dealer. The parts for a rebuilt are not cheap nor is the machine work, figure about $3000, so it has to be of value to you. All of the 4BTs I've seen seem to keep running and running. My current one was leaking coolant out of the head gasket (normally a no-no) but ran perfect and had good compression so replacing the head gasket (which is about a 2-3 hour job on one of these!) was ridiculously easy. So all food for thought. If it runs and you can get it cheap it would be a good way to go...

 

[Rovertrader]

was thinking a Garrett on the 24 valve, and a mechanical pump which I hear is quite a combo and eliminates lots of issues. Maybe stick it in the 47k mile 1983 2500 Suburban I just found. Is it really that simple though? The 4BT would fit lots of projects, and as you said, seem to never give up the ghost...

 

[lt1fire]

Wait until you actually are around one. A conversation with the hood up is impossible. Inside, you will be borderline yelling at your passenger and everything will shake. Sounds cool but you, like many who have done these conversions, will change your mind. You can not change the fact that this motor was never intended to be in anything smaller than a step van.

Not true at all unless it has been tuned to be this way. My buddy's 95 with a 4bt in it is louder than stock but very liveable, and since the sound deadening has gone it is wonderful.