Turbo time update with Pics!

[39Ronin]

So after driving the G for a couple of months I have decided to swap my 5cyl 3.0L N/A engine for the a Turbo'd 300D engine. I live in the mountain town of Squamish, BC which lies between Vancouver and the famous ski resort of Whistler. Although I am at a fairly low altitude I commute everyday with many long 9 - 10 % grade hills. I can do about 110 km/h on the flats but on the hills I can bog down to as low as 65 km/h so it makes for a painfull commute. The original engine boasts a whopping 88 horses while the turbo'd engine has 130 horses, but is also can be tuned for more.

I purchased a running 300D with 390,000 miles on it for $350 cdn. I pulled the motor out yeasterday and I plan to strip it down and do a full engine rebuild prior to installing it in my G. I will try to keep this updated with my progress as the project moves along. It will be done in my rare spare time but hopefully I will be done by the end of the summer. Also in the plans are a waste veggie oil kit and a set of 33x10.5 tires.

 

[Fernweh]

Good project to do, the normally aspirated engine with its 88hp is really not very powerful.......

I must congratulate you for your decision to complete overhaul the transplant first, while most the people who did the work just dropped that old turbo motor into the G-wagen and run it that way.

There are a few other issues, like transmission input shaft bearings you might have to look into as the turbo motor has quite a bit more torque.

The other thing is the tire size you would like to run on your g-wagen. With 33" tall tires and without changing the diff gearing you might loose all that gained hp and crawl up the grades with 65km again.

I have experienced that with my "powerful" 300GE M103 engine until I did the needed diff gear change to compensate for the large tire dia.

The P3 forum has a vast information on the work you have in front of you - go there and search for it.

Good luck and keep us posted on your progress.

 

[michaelgroves]

I'll be watching with interest! My 460 model 300GD is also much in need of more power, so I might consider something similar.

 

[4Rescue]

OOOOH neat, I can't wait to see this and the final product. I'm pretty dam happy with my truck, but man, a Turbo-Diesel would just make it perfect. Good luck on the swap, I'll bet it'll make a great truck even better eh...

CHeers

Dave

 

[39Ronin]

Good project to do, the normally aspirated engine with its 88hp is really not very powerful.......

I must congratulate you for your decision to complete overhaul the transplant first, while most the people who did the work just dropped that old turbo motor into the G-wagen and run it that way.

There are a few other issues, like transmission input shaft bearings you might have to look into as the turbo motor has quite a bit more torque.

The other thing is the tire size you would like to run on your g-wagen. With 33" tall tires and without changing the diff gearing you might loose all that gained hp and crawl up the grades with 65km again.

I have experienced that with my "powerful" 300GE M103 engine until I did the needed diff gear change to compensate for the large tire dia.

The P3 forum has a vast information on the work you have in front of you - go there and search for it.

Good luck and keep us posted on your progress.

Good points, I am member over at the P3 forum and have been in contact Warren T in regards to the swap. He advises to use the sedan transmission with the sedan turbo'd egine and 32 - 33 inch tires.

The way I have it figured is:

Currently I have 88hp with the static loses I figure I am only getting 40hp to the wheels, so with the turbo'd motor at 125hp (maybe more after tweaking) I should see almost 100% increase to the wheels. The torque is also increased with the turbo'd engine. I will prefer to run 33's for better clearance off road but I don't want to cancel out the gains by running a bigger tire, so i will try some 33's I have and still hang on to the 30's I am running now just in case.

These are my stock OM617#'s versus the turbo'd OM 617A

W123.130 1976–1985 300D 3.0 L OM617 I5 Diesel 88 PS (87 hp/65 kW) @ 4400 169 N·m (125 lb·ft) @ 2400

W123.193 1980–1985 300TD Turbo 3.0 L OM617a I5 Diesel 125 PS (123 hp/92 kW) @ 4350 245 N·m (181 lb·ft) @ 2400

Cheers,
Neil

 

[redthies]

Ok... Now I REALLY need to make the eight minute drive over to your place and check out your G... I might even get a day off some time this summer!

 

[michaelgroves]

Good points, I am member over at the P3 forum and have been in contact Warren T in regards to the swap. He advises to use the sedan transmission with the sedan turbo'd egine and 32 - 33 inch tires.

The way I have it figured is:

Currently I have 88hp with the static loses I figure I am only getting 40hp to the wheels, so with the turbo'd motor at 125hp (maybe more after tweaking) I should see almost 100% increase to the wheels. The torque is also increased with the turbo'd engine. I will prefer to run 33's for better clearance off road but I don't want to cancel out the gains by running a bigger tire, so i will try some 33's I have and still hang on to the 30's I am running now just in case.

These are my stock OM617#'s versus the turbo'd OM 617A

W123.130 1976–1985 300D 3.0 L OM617 I5 Diesel 88 PS (87 hp/65 kW) @ 4400 169 N·m (125 lb·ft) @ 2400

W123.193 1980–1985 300TD Turbo 3.0 L OM617a I5 Diesel 125 PS (123 hp/92 kW) @ 4350 245 N·m (181 lb·ft) @ 2400

Cheers,
Neil

Looking at the comparative figures of the two engines, it seems to me that you will be way better off with 33" tyres, even if you kept the same gearbox. Your increase in power and torque is proportionally greater than the increase in wheel diameter. So your new effective torque in every gear will be no less than it is right now, and you should reach maximum revs in each gear just as quickly, if not quicker, despite that representing a higher road speed.

Of course, there are probably better ratios for your new engine and tyres, but I'm pretty sure you wouldn't cancel out your gains by going to 33s.

 

[Gurkha]

The ZF 5 speed G/18 used in Euro 300TD is rated for 160bhp so if you have that tranny, you would be fine for the 130 horses made by your turbo 617, I have a spare turbo 617 lying and if your project works out, I will graft that into my Gurkha.

 

[Fernweh]

If you increase the diameter of your tires you will loose approximately 10% on engine power for each 1" in increased tire size.

Starting off with the - I do believe stock size - 29" tire and change to a 33" tire you are looking at almost 40% power reduction - from the new turbo 130hp down to 78hp.

Just from the increased tire size the top speed should be faster at a given rpm, but you will never get there - engine power loss.

 

[39Ronin]

I plan to get more HP from the turbo engine by tweaking it, my friend is a tuner by trade and thinks we can get 150 HP after some mods. I can't comment in great detail yet as I haven't asked exactly what he is planning but I will share as soon as I know. He has a 1991 civic with over 300hp. I am not as concerned with fuel economy as I will be running veggie.

 

[michaelgroves]

If you increase the diameter of your tires you will loose approximately 10% on engine power for each 1" in increased tire size.

Starting off with the - I do believe stock size - 29" tire and change to a 33" tire you are looking at almost 40% power reduction - from the new turbo 130hp down to 78hp.

Just from the increased tire size the top speed should be faster at a given rpm, but you will never get there - engine power loss.

Sorry, but this is just wrong.

You lose no power at all by changing wheel diameter. And other thing being equal, a change from 29" to 33" will require only 14% more torque to turn the wheel.

You will need the same power to drive at the same road speed, but your wheels will be turning 14% more slowly. (Power=torquexRPM: your torque requirement is 14% higher, your revs are 14% lower, the power requirement is unchanged). If you use the power of your new engine, you can, of course go faster than with the old engine.

 

[Fernweh]

Sorry, but this is just wrong.

You lose no power at all by changing wheel diameter. And other thing being equal, a change from 29" to 33" will require only 14% more torque to turn the wheel.

You will need the same power to drive at the same road speed, but your wheels will be turning 14% more slowly. (Power=torquexRPM: your torque requirement is 14% higher, your revs are 14% lower, the power requirement is unchanged). If you use the power of your new engine, you can, of course go faster than with the old engine.

You are right.....the loss of torque is 3.5% per 1" diameter increase of tire size so all together it will a 14% torque loss.

 

[snyder.hunter]

Back on the subject here - the turbo diesel swap is one worth doing. I had an M110 engine in my SWB truck and it did not serve me well (overheated all the time, got awful gas mileage)

I found a motor in awesome condition (zero blow by, no leaks, turbo had zero play - couldn't ask for something better) and I threw it in the back of my G and drove up to Montreal and Warren and I worked side by side to put the motor in my G. Things like custom motor mounts, custom throttle linkages, shifter linkages, driveshaft spacers, heavy duty input shaft bearings, new clutch parts (flywheel, pressure plate, clutch, throw out bearing, pilot bearing) all had to be put into place. We also had to modify the air intake as well (didn't want to run the sedan airbox so we set up the G air box to work with the turbo inlet.

If you have any questions about the process you are more than welcome to PM me or ask here in this thread. I've driven over 2000 miles with the swap and have returned around 22-24 mpg and not had any serious problems at all. Woohoo!

 

[39Ronin]

Just an update: I completely stripped the engine down and the head and block are back from the machine shop, it is time for re-assembly. I will keep you updated in the progress.

 

[kerry]

Good swap. There's a diesel performance tuning thread focused mostly on the 617 engine over here:
http://www.peachparts.com/shopforum/forumdisplay.php?s=&daysprune=-1&f=15

That forum is where you want to be for tons of knowledge about MB diesels. The general consensus on that forum is that you are not going to make a lot more horsepower with the 617 turbo without a lot of $$. You can turn up the ALDA but without putting on a bigger turbo and an IP which sends more fuel, you're pretty limited.

Not sure about transmission in the G-Wagon but I would think a 5spd transmission from an MB van (207d, 307d, 407d etc) might be a good choice. They have a very low first gear.

By the way, I've owned a 300d with a 617 NA and a 300TD with a 617 turbo in Denver. There's a huge difference between the two engines at altitude.