Help me pick a diesel for a swap

[Curtis Mittong]

Long story short: Car in question is a 66 Bonneville getting a diesel swap. This has been a very long project that got shelved for almost a decade while I saved money, worked, moved, etc. Back when I originally planned this swap I didn't have many options and I was just going to put a 6.5T in it. In the last decade, multiple new diesels have come out and the tech has gotten away from me so I don't know which one to go with.

There are no plans for huge power. This will be a daily driver/tow rig. Think of it as a stock assembly with CAI, intercooler, big exhaust, and a custom (no smoke) tune. I can't really go too wild since I can't really fit a transmission in the tunnel that would take massive torque.

Obvious answer is Dmax, but I wanted your opinions on the others. Focus should be on reliability, parts cost, and a modest nod to NVH

- 7.3L won't fit. Too tall.
- Cummins obviously won't fit unless I want 10" of heads sticking through the hood and want the radiator zip-tied to the front bumper.

- 6.0L: once you fix the oil cooler/EGR cooler issues, is it a reliable machine?
- 6.4L: too complex? Easy to delete the stuff I don't need?
- 6.7L: should it even be considered?

Any others you can think of?

[Yukon6.2]

Why not stick with the 6.5?
Get a new p400 and a new mechanical pump.Add a better turbo and a few mods to up the power a tad,
Simple proven power and mileage,no computers,trans probley the same size as original.
Parts are cheep,work on it yourself,
thats my opinon
Thomas

[Curtis Mittong]

Yukon, the 6.5L is still in my thoughts. My main concern is that a stock Dmax just makes so much more power/torque that I might have more $$ and less oomph in a modded 6.5L than I would a stock Dmax. Plus, I've yet to meet a 6.5L that didn't belch black smoke trying to make power.

[DmaxMaverick]

True. It's hard to make power with a MFI without significant smoke. Of course, there will some guy who comes in and says he makes 1,000 HP and it doesn't smoke one bit. Take it for what it is. You have a general idea of what you want, and you are the one who has to drive and maintain it, long after you stuff everything under the hood.

I suggest a Duramax from a van. It will have less power than an out-of-box truck powertrain, but it will have more than most all 6.5's (250, but that's not permanent), won't smoke (less than 400 HP), and is already coupled to a 4L85E tranny (will fit where Allisons won't). If you are already OK with all the electronics required, the van combo will not need an additional communication interface (such as adapting a truck PCM to a non-Allison tranny). Custom programming will give you the power, smoke level, and tranny performance you need/want with the least headache.

None of the Cummins will fit, reasonably.

The 6.0L Ford is still a POS.

Any 2007.5 or later Duramax will require extensive smog equipment, or deletion and accommodation. Your local emission requirements may dictate how to do that.

[Curtis Mittong]

Dmax - the van 'max is on my radar. I know the longblocks are the same, is the detune in the vans done with programming or are there injector/turbo differences as well?

The other big one on my radar is a truck Dmax with a 6x tranny from TCI, but I can't get a straight answer on how much torque it will take.

[DmaxMaverick]

The truck-van Duramax difference is all tuning. It was detuned to accommodate the early 4L80E trannies, from my understanding.

A 6L90E (or other) tranny could be adapted, but that would defeat the convenience of the van choice. Anything other than an OEM combination will require some electronic shoehorn. Choose your poison. A 6 speed may not be an advantage in a car. They are higher geared than any truck powertrain was designed to operate. At higher highway speeds, it's likely you'll be under the turbo map speed, which may kill mileage, add heat and sooting (internal). It would be a LOT easier to use as much original design as possible. You will likely regret it later if you don't, for many reasons.

[Curtis Mittong]

The truck-van Duramax difference is all tuning. It was detuned to accommodate the early 4L80E trannies, from my understanding.

A 6L90E (or other) tranny could be adapted, but that would defeat the convenience of the van choice. Anything other than an OEM combination will require some electronic shoehorn. Choose your poison. A 6 speed may not be an advantage in a car. They are higher geared than any truck powertrain was designed to operate. At higher highway speeds, it's likely you'll be under the turbo map speed, which may kill mileage, add heat and sooting (internal). It would be a LOT easier to use as much original design as possible. You will likely regret it later if you don't, for many reasons.

Agreed. The 10.5" FF that I put in currently has 4.10s and I have 3.73s in a box if necessary. I haven't decided on a final tire size but there are even 3.42 and 3.21 gears from the aftermarket should I need them to fine tune highway RPM. The drivetrain engineering I have down pat, I'm just a wee bit behind on the latest diesel choices.

I really like the 6L90 idea and looked into it, but they really aren't much smaller than an allison. That plus the computer issues make it a tough one.

The 6x from TCI isn't a huge gearing benefit since it basically uses the OD as a gear splitter in a 4L80E case, but what attracted me to it was the standalone computer and its already very beefy. For not much more than a heavily built 4L85E, the 6x is a good start but I'm having trouble getting a firm torque/GCVW rating from TCI.

[DmaxMaverick]

I think you are WAY over the top with 4.10 gears, and even 3.73. 2.73, or taller, would be more inline with the chassis capabilities. A double OD would be a necessity, being limited on tire diameter and the lower gear. My 2001 cruises 70 @ 1950 RPM's and 55 @ 1500 RPM's, in OD, with 3.73 and 33" tires. If I had 27" tires, I wouldn't need the first 2 gears, and would be screaming in OD on the highway.

Nice choice of car, but it isn't a truck, and you can't make it a truck. You could put the body on a truck chassis, but......

What do you intend on towing? How heavy and to/from where? What do you think a 45 year old car frame should be capable of? Remember... It was designed to go really fast, in a straight line (which a Duramax will compliment very well). Even if you box the frame and swap in a truck rear axle, the steel is still 45 years old, and there's the other end to consider. The Duramax is quite a bit heavier than a 455. They plowed bad enough in original trim. It wasn't designed to do much more than squash bugs really flat on the windshield.

[Curtis Mittong]

Nice choice of car, but it isn't a truck, and you can't make it a truck. You could put the body on a truck chassis, but......

What do you intend on towing? How heavy and to/from where? What do you think a 45 year old car frame should be capable of?

Its more of a truck frame than you think :). Center frame rails were replaced with 3x4" square DOM and the axle-back is 3x3". There are also extensive body stiffening modifications including structural foam and welded braces. Still not a truck, and I'm not trying to make it a truck. Its a hot rod that will be used as a daily driver/tow rig. It will regularly tow a 3500 lb boat and occassionally tow a 6000 GVW 24' travel trailer. Neither one would be towed more than a half day except the boat which will make one trip per year on about a 3000-mile round trip to Canada.

You're right that it will never be a truck, but my biggest strengths are driveline and suspension engineering so I feel very confident. Heck, I used to tow that much with this bonny before these mods and it did pretty well except the sloppy steering box.

[DmaxMaverick]

OK. By the way you were talking it up, with deep gear ratios and such, I was beginning to have visions of a 5th wheel hitch in the trunk.

Your towing needs are light. Up the gear ratio and take advantage of the "car" characteristics. I'd still be very concerned with the front end. You are adding a couple hundred pounds, engine alone. The Duramax in front of a well built 4L80/85 with tall rear gears will serve all your needs, very well. Have another serious look at the van Duramax combo. Randy's Ring and Pinion can provide the 2.73 rear gears. Your DD may get you 30+ MPG, unloaded. Not with truck gears, though.

[Curtis Mittong]

OK. By the way you were talking it up, with deep gear ratios and such, I was beginning to have visions of a 5th wheel hitch in the trunk.

5th wheel in the trunk? Stop giving me good ideas :)


Your towing needs are light. Up the gear ratio and take advantage of the "car" characteristics. I'd still be very concerned with the front end. You are adding a couple hundred pounds, engine alone. The Duramax in front of a well built 4L80/85 with tall rear gears will serve all your needs, very well. Have another serious look at the van Duramax combo. Randy's Ring and Pinion can provide the 2.73 rear gears. Your DD may get you 30+ MPG, unloaded. Not with truck gears, though.

I basically plan to take the turbo map (which is pretty forgiving on an LLY) and look at it versus the final drive and tire size of a stock setup. Theoretically, I need to pick an axle ratio that is between the lowest cruise RPM that I'm comfortable with on the turbo map and the cruise RPM of a stock truck like my 04 2500 with 3.73s. Right now I'm measuring for possible tire sizes that will carry the GCVW and not look like 18-wheeler tires. Once I nail that down I can pick a ratio.

As far as front end weight... no worries. A complete Pontiac V8 is about 720 lbs. A complete Dmax is about 840.

[rockwool]

I have a few suggestions but I don't know how practical they are or if they'll even work, but they might. I'll leave that for you to check out.

At auctions or scrap yards you might want to check for a Mercedes 400 CDI engine and gearbox. There's also a 500 CDI (IIRC) and both are V8's. But I would also consider their V6 series of CDI's (300, 320, 350, etc) that might be powerful enough for your needs (stock or tuned).

I know VW and Audi are big on diesel in the US so check their stuff out too. I know they have nice 2.7L and 3.0L V6 TDI's and a V10 TDI but they probably also have a V8 TDI.

BMW also has powerful 6cyl diesels - 3.0L and 3.5L - and I know they deliver engines to a new purpose built police car in the US. Dunno for sure but they might also have a diesel V8.

Another long shot is a CDI from a Dodge Sprinter, they might be too week though.

[rockwool]

Checked some facts up and there seems not to exist any 500 CDI, at least not in a G-class.

The Dodge/Mercedes Sprinters in Sweden use the 270CDI which might be too weak for you, dunno if they run any bigger engines in the US.

EDIT: The Sprinter comes with a V6 in the US!
OM 642 V6 (http://en.wikipedia.org/wiki/V6_engine) 24v DOHC 2,987 cc (182.3 cu in) 184 PS (135 kW; 181 hp) 400 N·m (295 ft·lbf)
http://en.wikipedia.org/wiki/Mercedes-Benz_Sprinter#Engines


G-class:

270 CDI — OM612 2.7 L Diesel I5 (turbocharged), 156 hp (115 kW), 294 ft·lbf (400 Nm)
400 CDI — OM628 4.0 L Diesel V8 (http://en.wikipedia.org/wiki/V8) (turbocharged), 250 hp (184 kW), 411 ft·lbf (560 N·m)
320 CDI — OM642 3.0 L Diesel V6 (http://en.wikipedia.org/wiki/V6), 224 hp (165 kW), 397 ft·lbf (540 Nm)Source: http://en.wikipedia.org/wiki/Mercedes-Benz_G-Class


Chrysler 300's that are used as taxi cabs over here use the 320 CDI's:

In Europe and Australia, the 300C is available with a 3.0 L diesel (http://en.wikipedia.org/wiki/Diesel_engine) V6 engine (http://en.wikipedia.org/wiki/V6_engine) (internal code OM642 (http://en.wikipedia.org/wiki/Mercedes-Benz_OM642_engine)) developed by Mercedes-Benz (http://en.wikipedia.org/wiki/Mercedes-Benz). It produces 218 hp (163 kW) and 376 lb·ft (510 N·m) of torque and will soon be available with NOx BlueTec (http://en.wikipedia.org/wiki/BlueTec) clean-diesel technology. Fuel economy for the 300C diesel is rated at 26.2 mpg-US (8.98 L/100 km; 31.5 mpg-imp) City, 42.8 mpg-US (5.50 L/100 km; 51.4 mpg-imp) Highway and 34.9 mpg-US (6.74 L/100 km; 41.9 mpg-imp) on the combined cycle. Acceleration from 0-60 mph happens in 7.9 seconds while the top speed remains the same as the petrol V6 (140 mph (230 km/h)).

http://en.wikipedia.org/wiki/Chrysler_300#Engines (http://en.wikipedia.org/wiki/Chrysler_300#Engines%20Found%20one%20but%20it%27s% 20pricey:%20http://cgi.ebay.com/ebaymotors/USED-ENGINE-WARRANTY-MERCEDES-E320-CDI-DIESEL-111K-/180693104371?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a1225f6f3)[/quote]Found one but pricey:
http://cgi.ebay.com/ebaymotors/USED-ENGINE-WARRANTY-MERCEDES-E320-CDI-DIESEL-111K-/180693104371?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a1225f6f3 (http://en.wikipedia.org/wiki/Chrysler_300#Engines[/quote]%20Found%20one%20but%20it%27s%20pricey:%20http://cgi.ebay.com/ebaymotors/USED-ENGINE-WARRANTY-MERCEDES-E320-CDI-DIESEL-111K-/180693104371?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a1225f6f3)




EDIT: The E-class has much nicer outputs than the G-class:


- E 300 BlueTEC 2,987 cc (2.987 L; 182.3 cu in) V6 211 PS (155 kW; 208 hp)@?
- E 320 BlueTEC 2,987 cc (2.987 L; 182.3 cu in) V6 213 PS (157 kW; 210 hp)@3400 526 N·m (388 lb·ft)@1600-2400
- E 320 CDI (-2005) 3,222 cc (3.222 L; 196.6 cu in) I6 204 PS (150 kW; 201 hp)@4200 500 N·m (370 lb·ft)@1800-2600
- E 320 CDI 2,987 cc (2.987 L; 182.3 cu in) V6 224 PS (165 kW; 221 hp)@3800 510 N·m (380 lb·ft)@1600-2800
- E 420 CDI 3,996 cc (3.996 L; 243.9 cu in) V8 314 PS (231 kW; 310 hp)@3600 730 N·m (540 lb·ft)@2200http://en.wikipedia.org/wiki/Mercedes-Benz_W211#Engines

[convert2diesel]

Okay, I'll weigh in here. First of all, a stock 6.5 turbo with a few tweaks is more than sufficient to pull your TT. A stock 6.2 non-turbo is not!!! Verified this early on in the summer with a friends 99 6.5 K2500, mostly stock, and my 5,500 lb. travel trailer. Didn't even breath hard.

The 6.2 in the Roadmaster worked fine with a 3,000 lb Coleman pop-up but fell flat on its face with the aerodynamics of a TT. Have run the numbers for a Cadillac Fleetwood conversion and am faced with the same thought process as you. My choices are a 6.5/4L80 with a center mount turbo (not enough room on the passenger side for a turbo plus plumbing) from a Hummer or van or a Dmax/4L80 combo.

If I go the 6.5, it will be mechanical pump and standalone controller. This will be built from the ground up, using an AMG block and all the fun stuff. Due to the price, if I go with the Dmax, it will be a take out from a known good truck or Van. Any tranny guy worth his salt can make the 4L80 handle anything the Dmax can put out stock.

Looked at all the offerings from Europe and Asia and, while some looked good, parts availability and ease of installation brought me back to the GM diesels everytime. Size and weight wrote paid on the Cummins and the FlowerJoke was just wrong. The 6.5 with a mechanical pump is by far the most flexible conversion engine for these cars.

Don't worry about the weight. Both the 455 (and the 389 that was probably in it to start with) were very heavy engines to start with. The Roadmaster had a SBC in it and the 6.2 only dropped the front springs 1/2 inch.

The Bonnie used the same chassis as lots of commercial vehicles and your parts guy, or suspension guy can match weight and height on a set of springs for you straight from the books. You'll probably have to upgrade the brakes and would suggest the largest sway bars you can get, front and rear. The Roadie actually handled better after the diesel.

The best all round gears are 3.23 to 1, using 235/75/15 tires. In third, with the torque locked up, the numbers were dead on the power curve of the 6.2/6.5 up to about 65 MPH. If you can build your 4L80 to tow in 4th, a set of 3.42 or 3.73 will probably work as well but you will suffer with the mileage. In OD and 3.23s, with no trailer, the engine will just lope along and give you great mileage. If you can locate a 5 bolt, full floating axle the right width, this would be best. The 10 bolts had some real outer bearing problems when loaded.

Your chassis mods are good but I would suggest looking real closely at the rear wheel arches. The overhang on these cars is significant. Add an extra 500 lbs. to the furthest extreme of that overhang and your putting alot of stress on those arches. Make sure the reinforcement follows all the way forward to your side rails. Have seen the siderails fracture due to the action of a load distributing hitch.

Sounds like a great conversion, though a 66 Bonnie without the 389, just doesn't sound right. On the other hand, if its not a collectable, and you can justify it as a daily, than all the power to you. Actually with all the crap we have on these newer cars, and the associated nuisance repairs, it may actually make sense. Good luck on your project.

Bill

[rockwool]

I continued looking into modern diesels and even though they might be rare, European diesel V8's often weigh less than 600lbs and for that reason alone could be worth an extra effort looking for. Aluminum blocks might work just fine for your needs.

This is for example Audi's 4.2L TDI:


Dimensions:

length: 520 millimetres (20.5 in),

mass: 255–257 kilograms (562–567 lb) (automotive - 15 kilograms (33 lb) lighter than its 4.0 V8 TDI predecessor, 4 kilograms (9 lb) lighter than the all-aluminium alloy Mercedes-Benz (http://en.wikipedia.org/wiki/Mercedes-Benz) 4.0 V8 CDI diesel engine).


DIN (http://en.wikipedia.org/wiki/DIN)-rated motive (http://en.wikipedia.org/wiki/Motive_power) power (http://en.wikipedia.org/wiki/Power_%28physics%29) & torque (http://en.wikipedia.org/wiki/Torque) outputs, ID codes:
BMC: 235 kilowatts (http://en.wikipedia.org/wiki/Kilowatt) (320 PS (http://en.wikipedia.org/wiki/Metric_horsepower); 315 bhp (http://en.wikipedia.org/wiki/Horsepower#Brake_horsepower))
BVN: 240 kilowatts (http://en.wikipedia.org/wiki/Kilowatt) (326 PS (http://en.wikipedia.org/wiki/Metric_horsepower); 322 bhp (http://en.wikipedia.org/wiki/Horsepower#Brake_horsepower)) @ 3,750 rpm (http://en.wikipedia.org/wiki/Revolutions_per_minute); 650 newton metres (479 ft·lbf) @ 1,600-3,500 rpm
BTR: 240 kilowatts (http://en.wikipedia.org/wiki/Kilowatt) (326 PS (http://en.wikipedia.org/wiki/Metric_horsepower); 322 bhp (http://en.wikipedia.org/wiki/Horsepower#Brake_horsepower)) @ 3,750 rpm; 760 newton metres (http://en.wikipedia.org/wiki/Newton_metre) (561 ft·lbf (http://en.wikipedia.org/wiki/Foot-pound_%28energy%29)) @ 1,800-2,500 rpm
CCFA: 250 kilowatts (http://en.wikipedia.org/wiki/Kilowatt) (340 PS (http://en.wikipedia.org/wiki/Metric_horsepower); 335 bhp (http://en.wikipedia.org/wiki/Horsepower#Brake_horsepower))

http://en.wikipedia.org/wiki/List_of_Volkswagen_Group_diesel_engines#Six_cylind er_dieselsYou'll find VW/Audi V6 and V8 TDI's on the same page.



Looking at BMW diesels I remembered that Land/Range Rovers were equipped with them (M57) a few years back and might be easier to find that way.

Is 300-430 lb-ft of torque coming from their older in-line 6 cylinders enough for you?
http://en.wikipedia.org/wiki/BMW_M57

Their older V8's range from 413-552 lb-ft:
http://en.wikipedia.org/wiki/BMW_M67


...which lead me to this link:
http://en.wikipedia.org/wiki/Ford_AJD-V6/PSA_DT17#Lion_V8




Happy hunting! :)

[convert2diesel]

The issue here is not "what is the best diesel" but rather what is available. All of the engines you suggest I would give my eye teeth to get my hands on them. The probelm is we are at least 20 years behind Europe in automotive diesels.

The EU actually reward the public for going with diesels. Here we are expected to pay a premium, both on initial sale and in many jurisdictions, expected to pay extra for the fuel.

As a project/hobby vehicle any of the mentioned diesels would be a head turner but regardless of how good these engines are, if your using them as a daily driver, they still need to be fixed occasionally. Most of the bits required for our engines can be bought at our local auto parts store either as OEM or aftermarket parts. If I walked into my local NAPA store to buy an injector for the M57 Beemer engine, the parts guy would look at me as if I just stepped off an alien spacecraft. Needed a timing gear set for a Leyman Diesel belonging to a friend of mine, for his double decker bus he imported from England, and it took almost 8 weeks to get it here. The same part for the GM diesels is usually in stock.

May take a flyer with my brothers Subaru Outback (you call them Libertys) and have a gent in Australia ship me over the 2 liter Boxer diesel for it. Can't buy them here in NA. Will have to jury rig it onto the auto trans and maybe change out the axle gears, but it looks simple enough to at least source most of the bits. We'll see.

Bill

[Edahall]

I agree that the 6.2 or 6.5 GM diesel would be most appropriate for this application. However, someone did somehow shoehorn a Cummins 6BT into this 1970 Monte Carlo.

http://www.youtube.com/watch?v=RO_kjaxIDzc

[rockwool]

The issue here is not "what is the best diesel" but rather what is available. All of the engines you suggest I would give my eye teeth to get my hands on them. The probelm is we are at least 20 years behind Europe in automotive diesels.

I didn't mean to come out like that, I was just proposing what ever I could think of that could perhaps suit him.

"20 years behind Europe" might have been the case 10 years ago, but then GM acquired Alfa Romeo - which was/is one of the leaders in diesel technology. With their Lion series of engines Ford seems to have cached up as well, and Chrysler seems to have partnered with Lancia - another Fiat group brand just like Alfa - and thus will have access to the same technology. But, that's all new or semi-new stuff...




The EU actually reward the public for going with diesels. Here we are expected to pay a premium, both on initial sale and in many jurisdictions, expected to pay extra for the fuel.

In the case of jurisdictions that may be so in some/most EU countries, but here in Sweden the auto lobby has strongly been favoring gas over diesel. That's probably because Volvo used VW diesel engines before they made their own line of diesels (some 10 years back), and SAAB never even offered diesels until GM got hold of Alfa.

Today, still, gas and E85 is stupid silly favored over diesels with particulate filters even though the latter are far better in all environmental AND HUMANITARIAN (through lesser strain on the people in oil producing developing countries) aspects.

Here, the yearly tax for diesel cars are ~2-3 times higher than their gasser equivalent. The price at the pump compared to gas varies - sometimes higher/lower. New E85 cars often get a ~$1000 environmental sales premium, etc etc..

Although, initial sales price is also higher for diesels because of their more expensive technology, at least that's what I've been told.




As a project/hobby vehicle any of the mentioned diesels would be a head turner but regardless of how good these engines are, if your using them as a daily driver, they still need to be fixed occasionally. Most of the bits required for our engines can be bought at our local auto parts store either as OEM or aftermarket parts. If I walked into my local NAPA store to buy an injector for the M57 Beemer engine, the parts guy would look at me as if I just stepped off an alien spacecraft. Needed a timing gear set for a Leyman Diesel belonging to a friend of mine, for his double decker bus he imported from England, and it took almost 8 weeks to get it here. The same part for the GM diesels is usually in stock.

Yeh, and that's only because of there's a small minded elite at the controls. :mad:




May take a flyer with my brothers Subaru Outback (you call them Libertys) and have a gent in Australia ship me over the 2 liter Boxer diesel for it. Can't buy them here in NA. Will have to jury rig it onto the auto trans and maybe change out the axle gears, but it looks simple enough to at least source most of the bits. We'll see.

Bill

Although that 2.0L is quite weak, Subaru deserves major kudos for creating that flat diesel, I will follow their progress with great interest!

I've seen on youtube that they put these in VW type 3 Wanagons - the last good looking kleinbus - and make some serious killer vans out of them.

[convert2diesel]

A common misconception in Europe is that the big three have similar lines on both side of the pond. Almost none of the diesel offerings you guys enjoy are available here. The only diesel cars here are the Mercedes and the VW and only a limited number of models. The cost to certify a diesel here precludes many from making it into production.

The first two years of production of the Oldsmobile 5.7 diesel left a real bad taste in the mouths of NA buyers. It actaully was a good design but was rushed into production than re-designed by accountants. The result was probably the worst engine ever produced. After 1980 the engine was re-designed again and ended up being a reasonable engine. The fiasco in 78 and 79 pretty well wrote paid on the market perception. Last year of production was 85 and we haven't seen a diesel car here since, only trucks.

Bill