Home   Forum   Classifieds   Tech/DIY   News   Articles   Chat   Contact Us

Realistic MPG expectations thread

Forum rules
Welcome to the Tech/DIY information archive. This area of the board is for reference purposes, please direct general tech discussion to the G Wagen Technical Forum.
Johnny Christensen
Posts: 1370

Re: Realistic MPG expectations thread

Post#11 » Thu May 28, 2015 9:20 pm

Hi GermanStar.

That looks great. What kind of transmissions do you have in those. Manual / Automatic? Straight 1:1 or with a overdrive?

I take it, the GD300 is the 3L normal aspirated?

User avatar
grazza
Posts: 1013

Re: Realistic MPG expectations thread

Post#12 » Fri May 29, 2015 2:32 am

I recently measured 13.2L/100km.

OM606 na with turbo added, 11psi, no intercooler. Dieselmeken tuned IP with 6mm elements. ALDA not yet working (waiting for brackets to covert to horizontal fitment since its fouling the engine mount)
722.608 5-speed auto (overdrive 5th) with Ole's controller
265/75R16 BFG AT tyres on modified 8" wide steel wheels
roof rack with lights
no extra load weight or camper fitted

I may get better with the ALDA working. I would expect perhaps another 1L/100km saving without the rack and 31" tyres.

User avatar
GermanStar
Posts: 415

Re: Realistic MPG expectations thread

Post#13 » Sat Jun 06, 2015 3:24 am

Hi Johnny!

603 has 5speed manual and 4.88 diffs.

606 has 5speed manual and 44:10 diffs.

Bouth have 5th overdrive.

User avatar
inkblotz
Posts: 8202

Re: Realistic MPG expectations thread

Post#14 » Wed Jun 10, 2015 4:05 am

463, 603A, SWB, Autobox, Full-time AWD
18-23mpg

Mark

montyW
Posts: 10

Re: Realistic MPG expectations thread

Post#15 » Mon Feb 27, 2017 11:31 am

463.321, 603.972, 1994 G350 Turbo Diesel Auto LWB, permanent 4x4 on factory spec tyres.

Typically around 21 mpg (UK) brim-to-brim. Best result 25 mpg.

User avatar
tiktaalik
Posts: 709

Re: Realistic MPG expectations thread

Post#16 » Tue Jun 20, 2017 7:54 am

I have recently purchased a 300GD with an OM617A diesel engine and a 4-speed automatic transmission. I believe the gearing ratio to be stock: 4.9:1. I have only tracked fuel economy for 1600 miles. My last fill up was 14.6mpg (US), with a 16mpg average and a best of 17.1mpg. I know this is a heavy beast but I am still not very impressed with the fuel economy. What can be done to improve fuel economy on this particular set up?

User avatar
AlanMcR
Posts: 7729

Re: Realistic MPG expectations thread

Post#17 » Tue Jun 20, 2017 8:58 am

This might be illustrative of the challenges of the OM714A with stock gearing. Optimum fuel efficiency is in the center of that eye:

OM617APerformance.jpg
...Alan

User avatar
Chris
Posts: 4549

Re: Realistic MPG expectations thread

Post#18 » Tue Jun 20, 2017 9:10 am

Try to never drive over 45mph, you may get nearly 20 mpg.

I get 14.7mpg (US) in the wife's OM617a powered 230G cabrio on 35" tires (4 spd manual, 5.33:1 axles) when cruising 65mph with frequent WOT bursts up to redline/4400RPM, it's quite challenging to not use the full ~200hp afforded by the new IP and turbo, If I never exceed 3500rpm the economy figures easily reach 18-19mpg.

Manual transmission with overdrive should yield a 1-2 MPG improvement in fuel economy too, huge tires or "fast axles" (4.36:1 ratio) would do the same thing, but if you are at stock OM617a power levels the G may loose too much 'drivability'.
IG: #traildustrestoration

User avatar
tiktaalik
Posts: 709

Re: Realistic MPG expectations thread

Post#19 » Wed Jun 21, 2017 2:36 pm

Thank you. Very helpful. I'll slow down and see if it makes a difference. Do any of you have a Webasto Coolant heater installed? I have a Webasto Thermotop C that I'm contemplating installing. Would that improve the fuel economy? I've heard it might.

User avatar
AlanMcR
Posts: 7729

Re: Realistic MPG expectations thread

Post#20 » Wed Jun 21, 2017 2:57 pm

The coolant heater would help (a little bit) if you lived in a super cold area. Otherwise it it more of a comfort thing.
...Alan

Return to “Tech: Diesel Engines and Conversions”

Who is online

Users browsing this forum: No registered users and 14 guests