Put the 235/75s in the calculator and it looks like 2600 rpm would result in 54 mph and 2900 rpm = 60 mph, if it's strong enough to do it.  May just work.

I think you are on the right track now.  I would plan for the top cruising speed at 55-60 mph-I think that is pretty realistic with the 1.6 and non-agressive-tread 235/75 tires.  Beyond 60mph, the Samurai aerodynamics, or lack there of, really start to impact the vehicle rolling resistance load.

If you need more power or a little bit of breathing room at the top end, you could swap out the fifth gears in the transmission.  What year is your Samurai?

It's an 87, so I believe I've got the best stock gearing already.

If it were available a 3.36 gear set with original tires seems like it might work even better.  Would put it in the 10% range and lose the added weight and rolling resistance of the larger tires/rims.  But the larger tires will certainly be more aesthetically pleasing with the lift.

J.T.

With the 205/70 tires at 55mph and the .795 fifth, you will be spinning at 3000rpm.  Pretty wound up for a diesel, but just getting it to the sweet spot for the 1300cc Suzuki.

With the 235/75 tires, 3000rpm will yield 62mph.  At 55mph it will be spinning at 2700rpm.  Sounds like that is pretty doable gearing wise.  You need to be spinning several hundred RPM higher than the engine did in the Rabbit to push all that air in front of the Samurai.

At least with 235's you can get away with not putting on a lift. 

What about an Isuzu diesel?

At least with 235's you can get away with not putting on a lift.  

What about an Isuzu diesel?

I believe I read that he just bought the Rabbit.

I've seen the Isuzu Diesel swap done too..around 1998.  From what I remember the engine was quite physcialy large and that it weighed a lot.  I remember the owner was having problems with the front springs collapsing under the weight.  The rig was a dedicated trail rig too.

For a Samurai, I think the VW Diesel, due to its smaller size and weight, is probably a better choice over the Isuzu.  IMHO, the VW NA diesel is a great choice for a trail rig-that low end chugability is awesome.

At least with 235's you can get away with not putting on a lift. 

What about an Isuzu diesel?

I'll still lift but nothing too aggressive, I was a big fan of OME before I ever thought of owning a Sami and probably would have put a set under it even if I didn't think the couple inches would be helpful for the diesel swap.  It'll be a good choice all around, saving my oil pan from those monster speed bumps and guaranteeing the taller tires fit well.

Rash is correct in that I already bought a Rabbit donor.

The Samurai I have is an 87 Tin Top in excellent condition inside and out.  Once I finish the engine swap and clean up the wire harness it's going to receive a frame up restore.  Finishing touches will include a bed liner under carriage coating and Dynamat insulation throughout the cab.  My first vehicle was an 89 Mazda B2200 LX, this Sami has the same look and feel of my beloved truck with the advantage of being 4wd.  I will have my trophy 80s ride and it will be beautiful.

The OME lift is a good daily driver lift.  It lifts it about 2" and will allow for up to 30" tires. 

I have a clean '87 tintop in my stash as well.  Gotta work on it this weekend-the brakes.  It has a 1600cc Sidekick enigne, weber/header, 0.795 fifth, a 4:1 t-case and 215/75 tires.  I was contemplating a OME spring set install on it a few months ago, but decided to just drive it one more year with the stock springs.

I've seen the Isuzu Diesel swap done too..around 1998.  From what I remember the engine was quite physcialy large and that it weighed a lot.  I remember the owner was having problems with the front springs collapsing under the weight.  The rig was a dedicated trail rig too.

For a Samurai, I think the VW Diesel, due to its smaller size and weight, is probably a better choice over the Isuzu.  IMHO, the VW NA diesel is a great choice for a trail rig-that low end chugability is awesome.

Might be thinking of a different diesel.  I was going for the 2.2l C223, from the Luv/Pups or the 1.8l 4FB1 from the Chevette/IMarks.  Both are pretty light for a diesel.

No it was the 2.2 Isuzu.  I can't find any definitive info source, but a quick search states that they weigh around 400-500lbs, which is quite a bit more than the Suzuki engines.

Been reading a lot of praise for http://www.performancediesel.ca/index.htm

If I'm really feeling the lack of power getting the IP tuned may bump me over the threshold and based on their claims could possibly increase fuel economy under normal light driving conditions.

As soon as I pull the engine I'll replace the head gasket, port and polish valves, replace all pumps except timing and vacuum, replace timing belt and rebuild injectors as standard procedure before putting it back into service.  I'll have to think on it due to the cost but it would be the perfect time to send it off.

So many choices

I run both diesel and gas in com pairable Ford work trucks . Both 95s both 4wd both standard cabs . While the diesel is better at pulling a trailer that's about the only advantage. Maintenance is higher cost not lower cost on the diesel due to the sheer volume of the fluids and filters required to properly maintain the rig . Fuel is more costly. Maintenance is more costly. And quite honestly the diesel (a power stroke) is just obnoxious to drive...IMO only.. I will say this though, when it comes to hauling a load it is my go to rig.... PS: I've had both rigs for 10 years and am basing my opinion on a ten year service cycle. If this doesn't sway you then here is a way to regear your Sammy - CJ5 axles -  ring and pinion gears for the rear 44 and the front 30 are available in almost any tooth count that you would ever need.....Boxcar....

I finally found the answer to my original question.  A 3.40 ring & pinion set came in the European diesel Samurais.  Now I suppose I need to weigh the value of a backpacking trip through Spain to visit a Pick 'n Pull.

Those 1.9 Peugot TD Samurais are very rare though.  I think they only sold them for a handful of years, maybe 98-2001 to the best of my knowledge, and those TD Samurais didn't exactly sell well.  I would give Axis Eng (or whoever is selling the kit now) a call and tell them what you have, and what you want to do and see what they say about the gearing.

If you really want a 3.40 r&p, I would get on a European Suzuki BBS and see if anyone has a set to sell.  However, I think that the 1.6NA VW engine doesn't have the low end grunt, nor the top end needed for this gear set.  The 3.40 gearset was for a 1.9 turbo diesel engine that churned out 89 ft-lbs of torque out at 2,000rpm and 63hp at 4,500rpm  Nearly 20-ft lb and 12hp more than the 1.6NA VW diesel.  

I would also like to point out that the 1.9 Peugot TD still put out less torque than the 1.6 8-valve Suzuki gas engine which put out 93 ft-lbs at 3,000rpm.  

The 1.6 8-valve actualy has a lot of low end grunt all the way from idle to the 3,000 torque peak.  I have a 1600cc 8-valve in a tintop Samurai that has a 4:1 t-case gearset, 215/75 tires, but is stock otherwise.  It's one super torquey and quick Samurai!

Noted.

I am staying the course of 235s and stock gears for my current ambitions.  I have a lead on a set in the UK that I may snag due to the rarity and rebuild a second set of axels with them to have on hand for the future.

My motivation for updating the thread was to provide proper closure, so many are left open ended which makes the trolls mad.  Just trying to keep the peace.

Thanks again for all your input, I'd buy you a beer if you weren't so damn far away.

J.T.