Supercharger v Turbo

Submitted: Sunday, Feb 09, 2003 at 21:41
ThreadID: 3291 Views:5599 Replies:5 FollowUps:13
This Thread has been Archived
I have a 1HZ 80 series diesel and chasing some more performance from it. After reading alot of articles about turbos and the 1HZ engine, it seems to me that this engine is not designed for a turbo and a turbo will certainly not do any good to the engines life?? I have been offered a second-hand supercharger for $3500 and I was wondering if anyone could recomend what I should do, as I understand the supercharger will have no damaging effect on my engine. Also I would like some info on how different the turbos and superchargers work.
Back Expand Un-Read 0 Moderator

Reply By: Truckster - Sunday, Feb 09, 2003 at 22:10

Sunday, Feb 09, 2003 at 22:10
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
AnswerID: 12766

Follow Up By: Kev. - Sunday, Feb 09, 2003 at 22:41

Sunday, Feb 09, 2003 at 22:41
Truckster, do you know of any other landcruiser forums that dont use your email as the online forum like the 80scool list.

FollowupID: 7439

Follow Up By: Truckster - Monday, Feb 10, 2003 at 09:36

Monday, Feb 10, 2003 at 09:36
Not really, But you can open a Yahoo account just for the forum, thats what I did for the Patrol list.......

Then it doesnt interrupt your work or home....

That is T H E Cruiser list.... You dont want to be elsewhere.
FollowupID: 7449

Reply By: Suzuki Viagra - Sunday, Feb 09, 2003 at 22:23

Sunday, Feb 09, 2003 at 22:23
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......
AnswerID: 12768

Reply By: Justin - Sunday, Feb 09, 2003 at 23:30

Sunday, Feb 09, 2003 at 23:30
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???
AnswerID: 12773

Follow Up By: Slunnie - Monday, Feb 10, 2003 at 01:13

Monday, Feb 10, 2003 at 01:13
Justin, you are comparing power at the wheels (your mechanics chassis dyno) to power at the flywheel (Toyotas engine dyno). Power at the wheels will always be less than power at the flywheel due to driveline losses and so can not be directly compared. Torque on the other hand will be more at the wheels than the engine due to the gearing down in the gearbox and diffs.
FollowupID: 7441

Follow Up By: Truckster - Monday, Feb 10, 2003 at 09:37

Monday, Feb 10, 2003 at 09:37
Larger exhaust is a waste of money.... Wont do crap.

And if your going to Turbo it, you will have to hack the new 'zaust up anyway...
FollowupID: 7450

Follow Up By: Truckster - Monday, Feb 10, 2003 at 09:39

Monday, Feb 10, 2003 at 09:39
Slunnie said it best..
The figures quoted from factory are always at the flywheel so they sound better....

Dyno is at the wheels...

injectors are $80ea depending where you go, (~$500!)
fuel pump is around $1500 to get done depending where you go... So not something to 'just get done' !!!
FollowupID: 7451

Follow Up By: Justin - Tuesday, Feb 11, 2003 at 14:39

Tuesday, Feb 11, 2003 at 14:39
Slunnie, Thanks for the input. Do you know how I can compare my dyno results to factory kw & N.M values either working them out to the flywheel or to the rear wheels to see if my vehicle is way underpowered?

Thanks everyone for their input!!!!
FollowupID: 7522

Follow Up By: Suzuki Viagra - Tuesday, Feb 11, 2003 at 17:37

Tuesday, Feb 11, 2003 at 17:37
Justin - there are ways that you can estimate the flywheel output form the measurable rear wheel output but they are at best an estimate. There's so many variables that it just isn't funny - the gear your car is in on the dyno, air pressure, air temperature, driveline frictional losses (eg gearbox, diff), tyre radius and wear, tyre pressures etc etc..... Also some factories used to cheat with their engine dynos by using no exhausts or just open pipes rather than proper exhausts, no fans alternators power steering or air conditioning pumps connected. "Optimised" fuel was also a favourite.

Companies like General Motors and Ford have both got into big legal problems regarding false power claims in the USA - Holden's still at it big time here with it's V8's (why do you think the "claimed" horsepower of the SS V8 didn't match the on road difference between it and the Windsor V8 Ford). Sure the Falcon was slower, but not 50 hp slower.....

If you're determined to try and guess - the normal "guess" figure for a passenger car is approximately 30% higher than measured at rear wheels if a manual transmission. Remember with heavier longer driveshafts, bigger diffs, transfer cases etc more drag will occur with a 4wd even before you put on bigger wheels or run suspesnion lift (which will further increase drag due to driveshaft angles etc).

Guessing 50% frictional losses puts you slightly (99kw) above factory which is pretty good for a tired old motor.

Besides that the dynos all vary in their reading - you could take it to another dyno and get 10% more power (or 10% less) easily.

A favourite trick in performance car circles used to be shop around for the right dyno so you can show a graph of 500 hp when your car is shown in a magazine. Visiting a couple of different dyno stations is the cheapest 50 horsepower you will ever make!

FollowupID: 7535

Follow Up By: Derek - Wednesday, Feb 12, 2003 at 00:19

Wednesday, Feb 12, 2003 at 00:19
Justin. F.Y.I. 1hp=.746kw and 1kw=1.34hp
1ft/lb=1.35582 Nm and 1Nm=.737562 ft/lbs.
The guy who tested my engine said that as a general rule of thumb,
1 hp at the WHEELS = 1 kw at the fly wheel. But then he's the same guy whose dyno said my 1HZ was developing 1356 Nm of torque.
And Andrew, do you know the difference between horsepower and brake horsepower or is it simply the terminology? Hope to hear from you soon.
FollowupID: 7569

Follow Up By: Suzuki Viagra - Wednesday, Feb 12, 2003 at 12:26

Wednesday, Feb 12, 2003 at 12:26
That figure roughly fits in with mine - since 1 hp = .75 of a kw. 30% improvement on the horsepower figure at wheels to guess flywheel = 0.75kw + 0.25kw (1/3 or near enough to 30%) = 1kw.

My understanding is that brake horsepower figure is to realign us horsepower with european horsepower figures. From memory 105 hp = 100bhp or 100ps (pferdestarke or something like that - german for horse power)

Obviously the germans had stronger horses.

FollowupID: 7590

Reply By: Pip - Monday, Feb 10, 2003 at 18:21

Monday, Feb 10, 2003 at 18:21
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!
AnswerID: 12822

Follow Up By: Peter L - Monday, Feb 10, 2003 at 21:30

Monday, Feb 10, 2003 at 21:30
Pip, I'm also interested in extra power from my 1HZ.
Please advise what headers, what exhaust and where you notice any differences.

Peter L.
FollowupID: 7482

Follow Up By: Derek - Monday, Feb 10, 2003 at 21:50

Monday, Feb 10, 2003 at 21:50
Peter. I've used Motivator extractors, a Mercury free flow muffler, a 2.5 in pipe, a Uni Filter and had the injectors reco'd (the pump was not touched in any way). The power has improved and the torque has improved significantly. It still won't blow off a council bus but it's heaps better than it was. It's the best money I've spent on it. Derek.
FollowupID: 7485

Reply By: Derek - Monday, Feb 10, 2003 at 21:40

Monday, Feb 10, 2003 at 21:40
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.
AnswerID: 12840

Follow Up By: Truckster - Monday, Feb 10, 2003 at 22:17

Monday, Feb 10, 2003 at 22:17

Im ditching the turbo and going with a 2.5in zaust!!!

But value of $4000 (mine cost $2800) is up to individuals.... mate got one the other day and like mine can now smoke up 33's :D
FollowupID: 7488

Follow Up By: Slunnie - Tuesday, Feb 11, 2003 at 17:46

Tuesday, Feb 11, 2003 at 17:46
On the chassis dyno the torque figures are higher than those from an engine dyno due to the gearing. Put the thing into L1 and what the figures go through the roof!

FollowupID: 7536

Sponsored Links

Popular Products (13)