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Engine / Transmission Swap

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grazza
Posts: 1013

Re: Engine / Transmission Swap

Post#191 » Mon Apr 27, 2015 3:20 am

Dont know where the 30mpg figure came from. Sounds like wishful thinking in my limited experience.
30mpg (US) = 7.8L/100km = impossible in any G-wagen ever.

I have one of 3 x om606 conversions downunder that we know of, and the best I have achieved is 17.5L100km (13.4 miles/gallon US) - this was the average on a 11500km trip, failrly loaded up.
This is not good.
I know of a friend getting 13L/100 in a 300GD (om617a) with a 5-speed manual.

But my injection pump has been from Australia to Sweden and back (dieselmeken, Goran) so we will see how the fuel economy goes when I get the G back home from the workshop. From the brief drive I had the other day with this tuned pump - the power was drastically improved (also from 5.5mm to 6mm elements)

However the old 4-speed auto was slipping a bit with the increased power so this week the 722.6 is going in...

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AlanMcR
Posts: 7729

Re: Engine / Transmission Swap

Post#192 » Mon Apr 27, 2015 8:57 am

30MPG (US) is wholly unreasonable with an OM606 in a G. Even the factory setup just hits 20MPG when driven with care. And that is with the 1:1.15 transfer case and 0.83:1 transmission putting the RPM into the perfect 2600rpm zone on the freeway. The best I've ever managed over any extended distance was 24MPG, and that was Tahoe to the Bay with a strong tailwind.
Based on some calculations that I ran a while ago, one could get the OM651 to achieve 30MPG, assuming that the gearing could get the RPMs down to 2200.
Upgrading the turbo, and manifold (for better flow), along with larger IP elements (for earlier burn), might just get you to a routine 23MPG.
...Alan

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grazza
Posts: 1013

Re: Engine / Transmission Swap

Post#193 » Mon Apr 27, 2015 12:12 pm

The best I have found on the net is the W461 G300CDI at 27mpg with the 183hp, a little better than the G350 with 211hp, 24mpg (both using the OM642 engine)

Suppatime
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Re: Engine / Transmission Swap

Post#194 » Mon Apr 27, 2015 12:44 pm

I won't defend the Auzzie, but he said he was running the 606 with factory turbo, adjustable manual wastegate set at 10psi, the 603 manual IP with stock 5.5mm elements. At best, he was making about 170hp, but more realistically, about 150.

I'm hoping for a similar setup, and if most of my driving is around town, I'm hoping for the 23-25mpg range. Hoping.

When I was able to drive my G, I was getting 20mpg with the OM617 non-turbo and 4-speed configuration. I have an overdrive 5th in my new Getrag, and while I'm not hoping for any miracles on the highway, I hope to see an improvement in economy, even if just by a little.
Filmmaker, Musician, Car Nitwit
Hollywood, CA USA

1980 Mercedes 300GD SWB - OM606/5-speed "Puchy"
2003 Mercedes C32 AMG "Dolores"- FLOODED AND TOTALED
2015 Kia Soul - BOOOOOOOO

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AlanMcR
Posts: 7729

Re: Engine / Transmission Swap

Post#195 » Mon Apr 27, 2015 12:54 pm

Considering that MB was claiming 22mpg for the OM606, I'd look on those numbers with some skepticism. Note that my claimed 20mpg is often met by doubters on the German G bulletin boards.
463_1996_G300turbo_G320_Page_21.jpg
...Alan

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vadimivanovich
Posts: 8643

Re: Engine / Transmission Swap

Post#196 » Mon Apr 27, 2015 1:43 pm

Drew, that 20 mpg was with a 617 NA, right? I assume you were going by the odometer reading as well? Unless it's been calibrated, the odometer is unreliable for mpg calculation. Expecting better economy at double the horsepower is optimistic to say the least... but hey, might as well try.

I started my diesel pursuit for economy & reliability. The 617a swap gave me better economy than the M110 originally in my G, but it's still nothing to get excited about. The 606a should do better still, but I'm not setting my hopes too high. If I can be consistently in the high-teens I'll be thrilled.

Now that I've driven the 617a for about 5 years, I'm ready to peel my foot off the floor mat and be able to climb the sierras in at least the center lane. I don't need a race-G, just one that is capable of doing everything without making me sweat an imminent overheat or get passed by another big-rig.

Economy is a subject we all want to impress people with, but these are simply heavy trucks and it takes a lot to move them.
"The way you think is the way you live"

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AlanMcR
Posts: 7729

Re: Engine / Transmission Swap

Post#197 » Mon Apr 27, 2015 3:18 pm

Suppatime wrote:I won't defend the Auzzie, but he said he was running the 606 with factory turbo, adjustable manual wastegate set at 10psi, the 603 manual IP with stock 5.5mm elements. At best, he was making about 170hp, but more realistically, about 150.

I'm hoping for a similar setup, and if most of my driving is around town, I'm hoping for the 23-25mpg range. Hoping.

When I was able to drive my G, I was getting 20mpg with the OM617 non-turbo and 4-speed configuration. I have an overdrive 5th in my new Getrag, and while I'm not hoping for any miracles on the highway, I hope to see an improvement in economy, even if just by a little.

5.5 elements are an mpg hindrance. The smaller the pump element, the longer the injection time. This leads to later injection and less efficiency.
...Alan

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grazza
Posts: 1013

Re: Engine / Transmission Swap

Post#198 » Mon Apr 27, 2015 4:22 pm

It would be awesome if I could get close to 10.6L/100km.
13L/100km might be a realistic goal, for country driving.

Some interesting comparisons (manufacturer specs): http://www.caradvice.com.au/compare-specs/

All turbo diesels.

....................................Engine.......L/100km...MPG(US)
Landrover Defender 110_____2.2L 4_____11.1______21.2
Landrover Discovery 4_______3.0L V6____8.8_______26.7
Landcruiser 76-series________4.5L V8____11.9______9.7
Landcruiser Sahara__________4.5L V8____10.3______22.8
Jeep Wrangler Sport_________2.8L 4_____8.0_______29.4
Jeep Grand Cherokee________3.0L V6____7.5_______31.3
Mercedes GL________________3.0L V6____7.7______30.5
Mercedes ML________________2.1L 4_____6.4______36.7

Suppatime
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Re: Engine / Transmission Swap

Post#199 » Tue Apr 28, 2015 12:14 pm

AlanMcR wrote:Considering that MB was claiming 22mpg for the OM606, I'd look on those numbers with some skepticism. Note that my claimed 20mpg is often met by doubters on the German G bulletin boards.
463_1996_G300turbo_G320_Page_21.jpg


Hm. Well, even 22mpg would be an improvement. I forget exactly which calculator I used, but someone had linked here on ClubG to a fuel consumption calculator based on diesel G engine variants and gearing... I'd gone over my ratios and thought that if I was able to keep my street driving between 30-40 mph in 3rd or 4th gear, I could be getting upwards of 27 mpg. Of course, with that calculator, my fuel economy dropped to a dismal 14 mpg above 65 mph.

Alan, yours is a completely factory setup, no? (I'm very curious how you got that into CA, by the way). Yours runs all the factory computers to an automatic transmission with the stock elements... and you also have the factory trap, increasing your back pressure (if ever so slightly).

I know Grazza has a 606 in his 460... I'm curious as to his economy in various conditions.

I didn't know the 5.5mm elements would be a hindrance. My girlfriend's E300D 606 non-turbo is returning about 30 mpg with that slushbox of a transmission, and she has a lead foot.

This will be interesting when I get to it. I wish I could say the body work is going faster, but I now have 2 body mounts that need complete fabrication (front passenger side was severed and I knew about it, but the next one back on the driver's side took over it's weight duties and was already rusty, so it's gone).

A couple more months for body... then front axle... then interior panels get redone while the engine goes in.
Filmmaker, Musician, Car Nitwit
Hollywood, CA USA

1980 Mercedes 300GD SWB - OM606/5-speed "Puchy"
2003 Mercedes C32 AMG "Dolores"- FLOODED AND TOTALED
2015 Kia Soul - BOOOOOOOO

Suppatime
Posts: 1215
Contact:

Re: Engine / Transmission Swap

Post#200 » Tue Apr 28, 2015 12:17 pm

vadimivanovich wrote:Drew, that 20 mpg was with a 617 NA, right? I assume you were going by the odometer reading as well? Unless it's been calibrated, the odometer is unreliable for mpg calculation. Expecting better economy at double the horsepower is optimistic to say the least... but hey, might as well try.

I started my diesel pursuit for economy & reliability. The 617a swap gave me better economy than the M110 originally in my G, but it's still nothing to get excited about. The 606a should do better still, but I'm not setting my hopes too high. If I can be consistently in the high-teens I'll be thrilled.

Now that I've driven the 617a for about 5 years, I'm ready to peel my foot off the floor mat and be able to climb the sierras in at least the center lane. I don't need a race-G, just one that is capable of doing everything without making me sweat an imminent overheat or get passed by another big-rig.

Economy is a subject we all want to impress people with, but these are simply heavy trucks and it takes a lot to move them.


20 mpg is on that 617. I have 30.5" tires on my G at the moment and it registers I'm going slightly faster than I actually am. Any calculations I've done have been on the fly by my trip meter and how many gallons I put in.

I'm hoping to at least tie my current fuel economy. That, coupled with actually being able to climb hills in traffic would be fantastic. I'm in the same boat as you, more or less.
Filmmaker, Musician, Car Nitwit
Hollywood, CA USA

1980 Mercedes 300GD SWB - OM606/5-speed "Puchy"
2003 Mercedes C32 AMG "Dolores"- FLOODED AND TOTALED
2015 Kia Soul - BOOOOOOOO

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