Thread: Sitec's 101..

Originally Posted by garrycol

I thought you had done this before - it did fit before I assume .

There's something exciting about taking a gamble with an even bigger engine and box!! As long as the fan is only 20mm off the rad, and I get my conversion plate to the LT slim the rear prop should still be a sensible length!!! 4/500mm

Originally Posted by Sitec

...my conversion plate to the LT slim the rear prop should still be a sensible length!!! 4/500mm

Make sure that the conversion plate, however you do it, is dowelled to either the gearbox, or the transfer box. If you rely on the fasteners to hold it in alignment, it won't be accurate enough and you will have shaft troubles. The same applies to the engine to gearbox junction.

The photo you posted earlier of the spaced conversion plate, didn't fill me with confidence but it would still work as long as it was dowelled,

Cheers Charlie

Yup, defo something that'd be happening. I'd planned to use M12 CSK bolts with Allen key heads to bolt the plate to the box, and then mimic the rear of an LT 77/R380 on the new plate. From what I can see, the shaft they've had made slides onto the ZF splines and is then held in place by the transfer case.... Another fella in the UK has done the same to his 110, and here's his conversion shaft.. Still worries me how this shaft will handle 200+ hp and 500nm of torque...

Well, if it works, here it is... The 6Bt running. Red light is oil, and white is charge.

Originally Posted by Sitec

Yup, defo something that'd be happening. I'd planned to use M12 CSK bolts with Allen key heads to bolt the plate to the box, and then mimic the rear of an LT 77/R380 on the new plate. From what I can see, the shaft they've had made slides onto the ZF splines and is then held in place by the transfer case.... Another fella in the UK has done the same to his 110, and here's his conversion shaft.. Still worries me how this shaft will handle 200+ hp and 500nm of torque...

Hi Simon,

If it's welded it will break. The problem it the side loading on the rear output gear (or input gear to the transfer case).

I once used a piece of a sliding female yoke spline from a Ford C6 Auto to mate a New Process 435 4-speed truck gearbox (same spline) to a Series transfer case. This tube was welded to a precision made Series rear mainshaft input section for the transfer case. Others did the same with Ford C4 Autos to Series transfer cases - all broke.

We had to make the C4s complete auto - transfer case shafts and have them heat treated and straightened. In the NP435s we replaced the mainshaft with one from an International that had an SAE 10 spline output and manufactured in R4 and Q5 (IIRC) internally splined SAE 10 for the box and Land Rover Series for the transfer case. We then supported the rear of the shaft with a new massive parallel roller bearing in a new support housing - losing any rear PTO output. The plan was nothing we made would ever break! - a good plan

Bob

Good info. Bob!

Wagoo told me by email, that he used an NP box on several Series Rovers; his method is to grind or turn (I can't remember which) the gearbox's output splines to a slightly smaller diameter and enlarge the internal diameter of the gear in the transfer case. This allowed him to run very powerful engines, such as big displacement V8 engines, without ever breaking the boxes,

Cheers Charlie

Originally Posted by chazza

Good info. Bob!

Wagoo told me by email, that he used an NP box on several Series Rovers; his method is to grind or turn (I can't remember which) the gearbox's output splines to a slightly smaller diameter and enlarge the internal diameter of the gear in the transfer case. This allowed him to run very powerful engines, such as big displacement V8 engines, without ever breaking the boxes,

Cheers Charlie

Hi Charlie,

Yes, you can close-couple the NP445 and 435 (and Turner, Borg-Warner, etc) as Bill did with an adapter plate (someone is mentioned on Teri-Anne's website doing them in the US) but I think we measured it up and the output flange was very close to the bellhousing and needed machining for clearance. Did not want to use a smaller diameter front tailshaft either. So we made an adapter 140mm long and supported that with the gearbox/transfer case crossmember so that the whole torque was not on the alloy LR transfer case attachment. That was with a 302 Windsor at over 250HP, mate has a 351 Windsor that used to make 400HP - he had to tone it down for his wife to drive.

Bob

The way I understand it the two pieces of the shaft are machined to an interference fit, pressed together, then welded and cleaned up on the lathe to suit.

Originally Posted by Sitec

Well, if it works, here it is... The 6Bt running. Red light is oil, and white is charge.

Nice, that'll be the most powerful sledge in SA.
Too bad you don't get much snow...