My son-in-law, a profession air frame mechanic turned multi-engine pilot, is getting serious about putting a Duramax in the '85 Regal, coupled to the wonderful Allison that was found in the Chevy Duramax Silverados. Seems he's beginning to think that since he'll inherit the thing in a few years, he might as well bring it up to date. Technically, he can do it. Probably would cost about $5000 if a suitable engine could be found. We could also sell the 454/TH400/Gear Vendors. The Regal has a very nice interior and could have a very nice exterior with a little work. Anyone know of this being done? My old Trek had a GM 6.3 in it but the P30 had a solid front axle. Maybe it would be wiser to look for a 30' rear engine Barth. Did they ever put a 8.3 Cummins with a 6-speed in a short Barth?
Jim

You might enjoy this video. Not a Barth or Duramax, but how about a 73 Travco with a 1993 Cummins? Just goes to show that anything is possible.

http://youtu.be/Vo11DG1nuGk

The Duramax is not without it$ $hare of problem$.

The 6.2 or 6.5TD is basically a drop-in (4L80E tranny). Equip it with a Suncoast Converters TC, and it's robust. If he's really handy, you can have the 6.5 I replaced in my coach (with the desireable 599 block) - needs a rebuild - for $400 (What I have in unused gaskets and turbo test)

I looked into it when the Duramax first hit the market. I was intimidated by the sump/crossmember clearance issues. It was really a moot point, anyway, as no donor vehicles were in the salvage yards yet.

The 502 I put in has as much torque as the Duramax, anyway.

Mileage? Well, uuuhhh, mmmmmm,

I thought about a Duromax. Issue to deal with are you need to start with a whole donor. Cast aluminum oil pan need modified. Motor- tranny mounts, need fabricated. Rear cross member relocated. Front springs replaced. Fuel delivery issue(tank pump,relays and high presure lines. ECU(computer)mounted and reprogramed and wired. Radiator-tranny hose connections. Accesory mounting(power steering pump-dash air).Vacume pump for dash heat controls, Exaust replacement. Dash modification to install donor dash. Drive shaft input. Rear end gear change ? Be 25 years old for the energy and time to do it. We can all dream though.and bench power our Barths.
I agree with Rusty. 6.5TD with 4L80E. With the O.D. engine speed should be about right. almost a dropin. no computer-would work great with fry oil. 11-12 mpg. Humvee donor.(wars winding down-govt surplus?)

Doorman

Is the 6.5 a normally aspirated engine? The 4L80E is a 4-speed, right? Would you continue to use the Gear Vendors? Sounds like an interesting possibility. Rusty, why did you change to something else?
Jim

Jim , the 6.5TD is turbo charged. This engine is an heavy duty version of the 6.2. This engine is based off the 454 block (external size, motor mounts, accsesory mounts, ect. It uses an engine driven injector pump. The 4L80E is a 4 speed, 4 gear being an overdrive. uses T400 output shaft. Not as strong as a 400 stock but can be upgraded with shaft and T.C. does have a lockup T.C. If done right it could look like a stock setup. The 6.2 is a normally aspirated engine that did come in the P-30 chassie. there are a few Barths equiped this way. Rusty has a AMG 6.5TD and modified 4L80E in his Breakaway. The AMG is a impruved version of the 6.5

Doorman

Not quite. but almost. The 6.2/6.5L are designs completely different from the 7.4L (454) gasser, although the motor mount arangements are the same. That latter engine was abortively made into a diesel, and GM had to redesign into the "Target" engine, and replace the first design. IIRC, that one was around 5.7L

The 6.2 was usually naturally aspirated. The 6.5L NA was extensively used in the AMG-built Humvee. When GM discontinued th 6.5L, AMG bought the rights and strengthened the block 25%. AMG also reduced the compression ratio from 21.1:1 to 18:1 (to increase longevity) and has Navistar do the block casting. The stock 6.5L TD produced 190 HP; mine is rated at 230 HP/420 lb-ft; I also had a gear drive installed to replace the timing chain. Peninsular Engines, who did my conversion, offers versions up to 450 HP.

The stock 6.5L had several block redesigns throughout its career. Only a couple of those are considered robust, including the 599 block.

The 4L80E is actually quite robust, but has weak points, among which are the spline, clutches, and torque converter. In stock form it's rated at 450 lb-ft of torque. Sun Coast Converters rebuilt mine with a brazed torque converter, HD clutches, and a machined spline, and it's now rated at 850 lb-ft. It's a 4-speed with a .75 OD.

Well this is timely. Do any of you know about the Heath Diesel Power Company? I guess they make coolers and other upgrades for the 6.2 and the 6.5....I was just talking to some folks here in the park and they were saying that they had spent the day getting some ecm upgrades on their coach. Turns out they had some work done a few years ago and they stop by to see Bill Heath every time they are in the area. Lives here in town but his factory is in Yakima. Sounds like an interesting guy, guess he set some sort of a speed record in a pickup a couple of years ago at Bonneville, will have to check with a friend of mine that goes to the salt flats every now and then and see if he knows him.

Heath has an excellent reputation on The Diesel Page, a website dedicated to the 6.2/6.5 series (and some Duramax).

Rusty, with your 4-speed, what RPM do you turn at 60 mph and what's your fuel economy? Is 4th gear the overdrive or is overdrive actually a 5th gear? If you don't mind, can you tell me how much an AMG engine would cost with the 599 block? Is it a direct drop in for the 454? Same question for the 4L80E. PM me if you want.
Jim

I run about 1800 RPM at 60 mph; fuel economy is 12+ mpg. Overdrive is the 4th gear. The 4L80E would need a controller, but is otherwise a near drop-in. There are several companies that supply already-strengthened 4L80Es.

The AMG engine would run about $10K; all use the Navistar block. 599 and other good blocks are used for rebuilds. The Peninsular Engines conversions can use all-mechanical components - no electronics for the engine.

Jim, Our coach runs 4.56 rear end gear. At 60 MPH I run just about 3000 RPM. If I did my math right with the 4L80E and locked up converter my RPMs would be around 2100 in 4th O.D. If you use your G.V. with the 4L80E you would end up around 1650. with 4.11 gear you end up in around 1900 in O.D. Running 225 75r 19.5s. This is not exact. but close. I using 103" as my tire dia. What kind of miliage are you getting with that G.V.?

We experimented with the cruise control on our Barth GTG trip to DC & Jim drove up without Cruise @ 58-60mph & we got 8mpg. I drove home using Cruise @ 62-65mph & we got 8.

Go figure.
Tere

East, uphill and tailwind, west downhill no wind.