A build up question for the Knights

[Biscuit]

I am starting to dream about FJ55s again (always wanted one but the availability in CO when I bought my 40 was limited to one and it was more work than I wanted at the time). I have started to put together in my mind what I would want to do.

Here is my current thoughts, I want to see if you, the Knights of the Iron Pig, see any fatal flaws in my idea. (i.e. don't want to get several thousand in only to realize my idea was flawed)

Years: 1974 or earlier chassis flipoff2: CARB and their regulations)
Engine: 1.9L VW TDI (now before you dismiss it, it has very similar specs to a 3B, and I can get the european variant that is more powerful that and the 55s are only 600lbs heavier or so than the Passats which ran that same engine)
Transmission/Tcase: MiniTruck, coupled to the TDI via an Acme adapter plate
Axles: Front cruiser stock, rear cruiser/minitruck hybrid to center the diff
Tires: I was thinking 31x9.5s on stock rims. Though if 33s fit without cutting (emphasis there) I will look into those.

Obviously I'm going to replumb the fuel system with a new tank, lines, etc. Maybe a 49gal extended range tank.

Let the comments begin.

 

[KliersLC]

I don't think you'll be able to turn the 33s with that engine unless you regear.

Other than that its sounds like a pretty good idea, you should be able to get around 30 MPG too...

Also, passats may only be 600 lbs heavier, but they are a heck of a lot more aerodynamic than a Pig. You might have trouble maintaining HWY speeds. What is your intended usage?

 

[scottryana]

I like the idea, but I am unsure how the 1.9TDI will perform pushing a pig. If diesel is really what you are looking for, I would have to suggest a cummins 4bt-4bta. The power and torque are very good. The only draw back is that the engine is very deep, so you would have to lift around 4" making the 33" tires a good fit. Isuzu also makes nice smaller 4 cylinders I think that they are called 4jb - 2.8L or 4bg - 4.3L. I think that a great resource that hasn't been explored is yanmar diesels they are small, lightweight, and very tough. What ever you end up doing make sure that you document it well. I really regret not doing that with my project.

Ryan.

 

[Biscuit]

Aerodynamics is a good point...I failed to think about that. Time to do some basic aerodynamic guestimating.

The major goal would be for more expedition-esque wheeling. More of the easier longer trails, no major rock crawling.

A 2.5L may stand a better chance of pushing the pig (150 or 180hp no torque figures yet). I'm just partial to the VW TDIs as they get way better fuel economy that most other diesels. Thankfully there is an outfit who can get them with less than 30,000 miles on them from Europe.

I'll have to look into the yanmar diesels, never heard of them, but to quote von Braun "research is what I'm doing when I don't know what I'm doing"

And oh you better believe there will be one heck of a good log and write up for this if I go for it. Heck it may just become a book...it would be a Knights of the Iron Pig Bestseller!

 

[Biscuit]

Here are the engine stats for all options on the table:

VW 1.9L TDI:

90hp@3750rpm
155ft-lbf@1900rpm
​

VW 2.5L TDI (harder to locate):

140HP@4000rpm
213ft-lbf@1900rpm
​

Toyota 2B:

93hp@3600rpm
159ft-lbf@2200rpm
​

Toyota 3B:

90hp@3600rpm
159ft-lbf@2200rpm

​

Toyota 2L-T:

86hp@4000rpm
139ft-lbf@2400
​

Cummins 4BT (all numbers AFAIK):

105hp@2500rpm
286ft-lbf@1700rpm

​

My current train of thought is that if a 3B could power the Pig then the 1.9TDI should also be capable of it.

 

[scottryana]

I think if you can find a 2.5L you will be much happier. All of those engines except the cummins and the 2.5L VW are considerably weaker then the F-2F that was in the 55. Once you load your 55 up, I think that it would be seriously pushing the limits of the small diesels. There is a green 60/62 on here that has a 4bt engine swap done by Profits, maybe you could track him down and see if he has any input. Dieselcruiserhead is also a good resource for diesel powered 55s.

Ryan.

 

[Biscuit]

Looks like the 2.5 will be perfectly sized now that I have done some research.

The UK version of the Audi Q7 has a 3.0L that can push all 5,200lbs of it up to 135mph. So a 2.5L should be able to push a 4,000lb 55 at highway speed just fine.

 

[dieselcruiserhead]

So you know the stock 3B is literally completely gutless wonder, especially with slightly larger tires (31s or 33s) and 4.10s. You can tweak the TDI's pretty well but it is a PITA. Regardless, you will have to use mini truck running gear (5 speed) which will be a shortcoming and weak because these are the only adapters available, unless you want to fork down $1000-$1500 for a custom adapter to use that particular engine, which I think is retarded.. What I would do is, if you want it semi stock, and still get similar mileage that you would get with the TDI: (maybe 30-33 with the TDI, boosted up to 125 hp, using a mechanical pump), is do an Isuzu 4 cyl diesel. Then get an adapter from isuzudieselswapper.com The Isuzu should fit in a lightly lifted rig, FWIW..

Or do the Cummins. But you need the big lift, 4" minimum, SOA preferred. Either will yeild low 20s in MPG, and keep you running fairly stout driveing gear. Hope it helps..

 

[dieselcruiserhead]

PS click the link in my sig. Outdated info but still some good stuff...