The Stovebolt Site Forums The Parking Lot Big Bolts 6.5 swap? 1966 GMC 960

I am contemplating putting a. 1993 6.5 turbodiesel in my truck, I was curious if anyone has done this? Will the vacuum pump on it be enough to run the booster? I don't see a way to use the hydroboost off the donor truck with the dual clutch/brake reservoir. It would be replacing 327 v8

Hy BorderMechanical, I confess I know next to nothing about the engine you are contemplating swapping into your truck. The scuttlebutt I have heard has not been positive, not terrible, but not positive. I believe there should be a clutch master available for occasions when the truck had air brakes, if you could locate one of those you could at least separate the two functions, brakes and clutch. Do some more research on the engine, see what people have to say about it

There are people in the 'states who support the 6.5 and it does well, I don't know who they are, perhaps they are in Salt Lake City. Google 6.5 info.

Ed

a '93 is better from the fuel system standpoint as it is still a DB series mechanical pump, '94 & up used a DS pump which has a electronic control system that was lets say less than robust. I'm a bit jaded as I've worked on all the G.M. diesel since I started in 1980. I can't say as I would swap one for a small block V8, would be a step backwards IMHO, I'd stay with sbc or go to a LS engine.

The vacuum pump on the 6.5 won't give you anything for the brake booster, it could barely survive for the turbo waste gate. Most 6.5 users did away with the pump due to failure.

I'd run the 6.5 if the block isn't cracked.
In fact I missed out on a 1992 6.5TD, auto that would have been a good fit for my '56.

so the 6.5 i have is from a 93, still in the db pump era, and i will now plan on an electric vac pump, reason for the swap is i need something that i can work every day without costing me a fortune on fuel, also will idle/high idle all day to run my air compressor/picker etc

I have some updates. Pulled. My 327, and the 6.5 out of. My donor. Also pulled my sm420 and. Am in the middle of a rebuild. I found a NOS countershaft for that, but could use a first/reverse gear if Anyone has one to spare.
Two issues came up so far.
1. The adapter plate to the much larger bellhousing had to be trimmed on the right side to clear the exhaust manifold.
2 the bellhousing itself, and more specifically the slave cylinder for the clutch won't quite clear the manifold.
3. Have to use the SBC starter as the teeth on the flywheel are different than the previous ring gear.
So that being said I can't 'notch' the bellhousing, as. That is where I need to bolt the SBC starter onto.
Possible. Solution is an aftermarket SBC turbo kit, or run it NA for a while. I'll have to see if I can find another option, I heard the van manifolds were different.
I'll post pics. Tomorrow

you can see where i notched the adapter plate for the larger bellhousing, but i cant notch the bellhousing as the slave cylinder for the clutch sits right there. my exhaust has to move out 2 ish inches

I have a couple of sets of 6.2 HUMVEE exhaust manifolds, they are welded steel tube but not turbo manifolds, you might be able to modify them to fit. I am in the process of building a 6.5 due to the inherent cracked block syndrome. I'm using a 6.2 block and all the externals of my 6.5 so I have spare parts if you need them.

I would be a little concerned about using a standard SBC starter for the 6.5, 20.5:1 compression ratio is a tall order unless you use a high torque gear reduction starter.

Not to mention 2 big cca batteries that definitely need to be up the chore when called apon.

I’ve not had a 6.5, but I’ve ran 4 different 6.2s at one point or another. Still have one 6.2. The biggest issue these engine have is a very heavy starter and it should have a bracket on the front for support. Many times people will install a new starter and not reinstall the bracket. Over time, the two bolt holes on the rear by the bellhousing will crack.... sometimes they crack and other times the bolts shear off in the block...

Bottom line, make sure you have the front support bracket installed!! If yours doesn’t have one They can be found cheap online.

Also check out the harmonic balancer... if they go bad, it can cause cracks in the block at the main web bolt holes and if bad enough it can even break the crank.

These items if checked and maintained will make your 6.5 last a long time.