Supercharger v Turbo

neither will do good to an old engine...

They both put LOTS of extra pressure on the motor. But out of the 2, they will be the same price in the end, Turbo is new and warranty, takes no engine power to run, eg extra pulley, and the supercharger will work lots better more power.

but jump on the 80scool list, 1000ish owners there, that have been thru this before....
Welcome to Land Cruiser Owners On Line

A supercharger or turbocharger both work in a similar way (by stuffing more air into your cylinder) but use different mechanical means to achieve it. Usually a supercharger will run at a lower boost pressure than a turbo so it will put lower strain on the motor in that way, but is mechanically driven which will create load in other ways - like on crankshaft bearings and front main seals.

Turbos use exhaust pressure that is just going to be wasted anyway, so don't create the same mechanical drag or drain on the engine.

Superchargers are normally set to provide lower boost levels at lower rpm - but with the right size turbo you can provide similar boost at similar rpm points - or vice versa - you can supply turbocharger type power with the right supercharger combo. Additionally they don't have the drain in bower a supercharger causes with associated belts and all that stuff. This is why turbo diesels are very common and supercharged diesels are not.

Using either a turbocharger or a supercharger on a tired engine is a sure fire way to need an engine rebuild - which is a cost you have to consider as at least a risk if not an outright purchase price - and you could get all your original power back and more besides with a good rebuild.

If your engine is higher milage you might be better off with a larger or later model diesel engine or engine management system to get the power you're looking for.

I'm no expert on diesels as most of my mechanical background is in passenger cars (performance and wrecking) and motorbikes (mechanic a long time ago) (although 2 strokes are similar to diesels in many ways), but I'd say that since the factory chose turbo over supercharger with it's millions of dollars worth of R&D so should you.

Personally I was planning on using a Toyota 4AGZE supercharger on my Vitara but now even I'm leaning towards turbocharging due to many of the above issues. My petrol engine is more desperate for the low down boost than your diesel is too so I should be more desperate for the supercharger.

Also $3500 for a second hand supercharger seems a bit steep to me.
As companies like CAPA who specialise in this sort of stuff - their systems usually aren't too much more for brand new stuff fitted with warranty - maybe $4500 or so depending on the size supercharger you fit and the difficulty in application.

As an example my cheapo supercharger I was gonna buy was worth $350 (but it's very small). I would expect more like $1000-1500 for a secondhand supercharger. Look in the trading post.

If the supercharger isn't exactly right for the car you can change the pulley sizes which changes how much boost is developed and where it comes in - also there's plenum sizes and a whole bunch of other stuff to consider. So you can buy that one off a drag car after all if you can get one real cheap......

Thanks Truckster, and Suzuki Viagra for your long explaination, it's greatly appreciated. I think i'll go the turbo after your info, but i might try a larger exhaust first. The cruiser has 150kms on the clock and is running very underpowered. I took the vehicle to a mechanic last week to help solve the problem. He ran it on the dyno before any work in 3rd gear and got 50kw @ 65kph (approx 3650rpm) & 511N.M @ 48kph (approx 2700rpm). After playing with the pump timing and tuning got 66kw @ 70kph (approx 3930rpm) & 592N.M @ 45kph (approx 2530rpm). It still feels very under powered, I think i'll get the injectors done and the pump checked and go from there. Apparently for a 1HZ the factory is 96kw @3800rpm & 285N.M @ 2200rpm - but what gear is that obtainded in, as both the power & torque values are considerably different to what the cruiser is currently outputting. Any ideas???
Cheers

Justin. The 1HZ motor is very asmatic so anything you can do to increase the amount of air getting in will make a big improvement. I put a set of headers and complete exhaust system on my 1HZ and am very pleased with the result. Smoother running engine and noticable power gain. Total cost around $700 so much less than Turbo'ing and without the worry of significant extra strain on the engine. If you go this route just make sure they install a hot-dog as well as a sports muffler. The noise is just too loud without!

Justin. I disagree with Truckster! I put a 2.5 inch system on my 1HZ and it made a world of difference. But he is right in that the excercise is pointless if you end up still unhappy and fit a turbo. Last year I had my injectors reconditioned, fitted a uni-filter and had extractors and the exhaust fitted. The engine developed 1000 ft/lbs of torque and 85 bhp in third gear and was much better to drive particularly when towing. I can't afford any form of forced induction but when you consider the cost of any upgrade a 308 on lpg looks mighty attractive. I'm running 285/75 tyres which are oversize and the dyno mechanic said they would be pulling the figures down. The question you have ask yourself is if you fit a $4000 turbo, will the car perform $4000 better??? Good luck with your decision.