Hydrostatic supercharger

[OzDave]

Gday all,

I'm just kicking an idea around at the moment, and thought I'd see what others thought of it... not going to be building it anytime soon, just jotting down some thoughts.

I've got a bit of experience with forced induction, along the lines of turbocharged imports, but have always reckoned that what was missing on the Max was a charger sucking through the intakes running the sides. Dig that can get probably get better performance with turbo's, but for sake of discussion just gonna focus on a charger setup.

I've looked at ones on the market, but gotta be honest, the idea of a belt spinning that close to my crotch would make kicking back and cruising a bit hard, seen too many V8's throw a belt at the drags. Plus I'd really like a setup that keeps the lines clean.

So after renting a dingo (mini loader digger thing) for some garden work I've become fascinated with hydraulic drive systems. Researching them I've found that they're surprisingly efficient, plus can be throttled etc.

So the basics of the idea is to have a pump bolted onto the flywheel, two hydraulic pipes routed up through the chassis and then bolting the motor onto the front of the charger.

A simple model would work just like a regular belt driven, faster the engine spins, the faster it pumps and the faster the charger spins, if you wanted to get fancy there are adjustable pumps and motors that could be used to regulate the speed the charger spins at allowing you to set boost curves and switch the charger on and off, but just looking at the basic setup I think it could work. It'd be heavier than running a belt, but a bit safer and clean up the aesthetics a bit.

What do people think?

 

[tugla]

wow pretty cool idea man. so have the hydo pump running on flywheel to turn charger to pump in air. dont think it matters how big or bulky it is , would sure make cool set up. what about the carbs? chg them or just re-jet.
so when you setting this up??? love to hear that beast fire up. what kind of charger were you thinking of?

 

[OzDave]

Aww if I was to try it I'd go cheap as possible to find out if it'd work. Reckon it'd be an SC14 toyota supercharger (bought for about $AU 300 at a wrecker) which is designed for a 1.4 litre engine (sorry, I'm a shocker at converting to imperial measurements but tis an American forum so best I can say is that's small four cylinder size.) The SC14 came in a bunch of MR2's and corola's.

When I'm not sure if somethings going to work I keep things cheap, so I'd try to rejet, otherwise probably looking at a 4 barrel holley from what I'm reading elsewhere... fuel injection would be best... and programable... but thats a big cost jump.

The airbox would probably go... I'm very hesitant to yank something like that, tuning an induction setup is a nightmare, trying to figure out the maths for the air waves for induction length... but its beyond me why a 1.2 litre 140hp engine has a filter thats 4 times bigger than the 2 litre 350hp engine in my Silvia... I'd yank it and probably look at an oiled foam setup. More maintenance, but I'm used to them and they flow well.

Then it'd be a matter of the hydraulics. I'd hope to find a pump that's roughly the same diametre as the flywheel cover, so then I can try to smooth it into the engine's lines. Hopefully itd just look the same, just 5 or 6 cm's (1 to 2 inchs) wider at the flywheel cover with two pipes coming out of it and disapearing behind the engine. I reckon the SC14 charger would be about the size of the airbox... but of course then there's the plumbing for the hydraulics and the intake, and I'd still need a filter. Wouldn't have to worry about induction so much though, found that when you got forced you dont need to worry as much about resonant frequencies, the beasty will just suck as hard as it can.

... heh... okay this is probably a stupid idea... but the Vmax already has two quasi hydraulic setups... a cooling system and a oil system in which liquids are compressed and forced through the engine... I wonder if you could just piggyback a hydraulic motor onto one of those systems... *scratches chin and has a ponder*

 

[Buster Hymen]

Aww if I was to try it I'd go cheap as possible to find out if it'd work. Reckon it'd be an SC14 toyota supercharger (bought for about $AU 300 at a wrecker) which is designed for a 1.4 litre engine (sorry, I'm a shocker at converting to imperial measurements but tis an American forum so best I can say is that's small four cylinder size.) The SC14 came in a bunch of MR2's and corola's.

This is actually a Canadian run forum so post all in metric if you want! :biglaugh:

 

[OzDave]

hey alright, score one for the glory of the commonwealth empire, I convert to imperial for no-one but if we're all counting to ten it's gonna save a lotta explaining.

Soz if i ruffled anyones feathers, calling canadians a yank is probably on par with calling an ozzie a kiwi. Saw the .com and made an assumption...

*edit* just re-read that and realised it could be read the wrong way, sure everyones cool, but just to make things clear, Kiwi's get wound up by being called aussies, and aussies get wound up when you call them kiwi's, not saying anyones better than the other, just that we get mixed up all the time, no doubt same for Americans and Canadians.

 

[OzDave]

oh and on topic, have been sitting around thinking about how hard it'd be to pull the pipe from the water pump and route it so in spins a hydraulic motor then have the water exiting the motor going back into the cooling circuit... I mean it leaves a whole lotta question about the amount of water that's flowed at what pressure, strain on the pump etc... But if u could actually make use of the hydraulic pressure in the cooling system... Well just think of the potential! Wonder if it's possible to upgrade a water pump...

 

[gamorg02]

off topic. i like dealing with metric over SAE. doing lots of physics in college helped bang that in too.

on topic. sounds like a neat idea man!

 

[naughtyG]

Can we quit on the dual topic posts - it's confusing the Franglish in me! LOL

 

[tugla]

not sure you would have enough pressure from the water pump to drive the s/c fast enough to make it worth while :ummm: guess you would have to do a test and see the flow rate. I would think switching over to the holley would make tuning a lot easier, even running a q-jet would be cool( i'd run that route but i like q-jets thats why).

as for the cdn vs american thing, not sure about most of the guys here but ya for sure rather not be mistaken for one, but no hard feeling know what you meant.

 

[4gasem]

http://www.youtube.com/watch?v=neyqXj-txFA

http://www.youtube.com/watch?v=5TrvXwoGKKU&feature=channel

Hydrostatic!

 

[06VMAXIMUS]

If you use a hydraulic pump, you will probably need to run some sort of a cooler. Shes gonna get HOT!!

 

[hubeerjw]

I was about ready to post on the "Heat" issue. Hydrostatic drives do create a LOT of heat!!!!! Most of the inefficiencies are due to heat. A simple air to oil cooler would cool it quite well and are all over. My 600 Katana uses an oil cooler instead of a radiator and would work quite well in this application and would provide more than enough heat rejection. Most of your time will be sizing components, and then trying to find the right component to fit your application. There are variable flow pumps out there that would also be pretty trick. You may even be able to mount the pump on the secondary gear cover... now go with me for a second on this. If you had it mounted to the transmission, you wouldn't be getting much for gains when you are in 1st or 2nd gear, but really, you don't need it there too often. But when you start spinning the transmission a little faster the pump spins a little faster and then the boost starts to show up. I'm not sure what the deceleration would be like and if still want to go after you let off, but it sounded good to me.... until you start putting it down on paper and creating all the "what if" possibilities. If you need help with some simple component sizing and flows let me know and I may be able to work on some calcs to get you in the ball park at least.
Jeff

 

[Birdoprey]

You would'nt want it hooked to the tranny or final drive. You would end up with mucho boost at too low revs when in the upper gears. Also, boost would build waaaay too slowly if blower is properly sized. Needs to be either driven by engine rpm or by engine load. Neat thought though. Thats the kinda thinking that spurs GREAT ideas!

 

[OzDave]

Yer, that's the problem when you go into the vast unknown like this, there's no similar setups I can just modfiy to suit, gonna have to figure out all the sizing from scratch and that means wandering around asking people questions they really dont want to answer like "How much extra stress can the water pump handle?"

Now personally I reckon the simplest solution would be to piggy back on the oil or coolant circuit. Out of the two I prefer... coolant!

I know it sounds arse backwards, but I'm thinking of what will happen in a failure scenario, especially with placing extra load on circuit. I'd definately prefer a coolant system failure to a lubrication.

Well I'm reckoning the coolant system will probably have a 14 psi cap on it... which is pretty low by hydraulic standards... Course there's two parts to hydraulics, pressure and flowrate... if it's 14 PSI at a massive flowrate might be enough to push 7 or 8 PSI down the neck of the Max... but I've got no idea what the water pump pushes out. Been hearing a lot about electric water pumps lately, so I'm quessing it's probably not going to be much... but if the water pump could be upgraded... Some hulking great unit designed to force coolant through a truck or V8... course that might cause the rest of the system to blow apart at the seams... but if I could upgrade the system rather than trying to hook up another one it'd be something indeed. Just imagine it, ya pull out the water pump, bolt in your new one, rejet the carb, then pull one of the pipes and replace it with two pipes leading to and from the charger... no belts to route etc etc...

Course its always simple to say... Realistically... how much power does it take to run a supercharger? Though the oil pump and water pump are both directly driven by a 140hp engine, they're probably not going to able to take the strain of a supercharger through their circuit...

Just did a google on Hydrocharger's to see if anyone else has had a crack at it... looks like garrett's worked on something of the nature.

http://www.theautochannel.com/news/press/date/19980225/press010273.html

Though the report is from 1998... wonder if they hit a wall...

Well anyways, I think unless someone has some figures on what kind of numbers u get from the cooling and oil system my time would best be spent looking at a matched pump and motor in a completely independant circuit. My thinking is its a case of hooking up the pump, possibly running to a second radiator then hooking up the motor to the charger, return the pipe coming out of the motor back to the pump and spin the circuit. Use the gearing used for traditional belt driven chargers to size the pump's and then just get ones that are strong enough to survive the stress.

I'm really tempted to try builidng one... the whole using hydraulics instead of belts seems simple enough... but the whole converting from a stock N/A to a forced setup is gonna be what makes it expensive, new carbs... probably an engine teardown... Of course I could just whiff one or two psi in through the top... just to see if it works...

 

[06VMAXIMUS]

I think its a great idea to kick around. I don't believe the water pump would provide enough pressure to drive anything (I may be wrong!!). The hydraulic oil idea is great also, but heat and room to plumb it may be a problem. Belt drive is probably the best route, I think the materials they make the belts from nowadays are almost bulletproof. Yes, I have seen them blow apart on high horsepower engines, but the max doesn't put out that much. A hydraulic line failure would be almost as bad as a belt failure when its that close to the "family jewels". Not trying to shoot anything down....just throwing up some thoughts!!

 

[OzDave]

How does this sound for a hydraulic setup. Power steering pump geared down to sit on the flywheel, going up to another power steering pump running backwards... essentially acting like a motor, to drive the supercharger.

Been idly looking at price of hydraulics in my spare time... rather terrifying stuff. Thinking I'm gonna want stuff I can bodge up. Power steering pumps are cheap enough at wreckers and a good 4wd one can flow 15LPM at 1450 PSI which should be enough to push a supercharger around once its geared properly. Plus if I go with power steering there's also power steering coolers etc that are all sized properly for the systems.

2 power steering pumps plus an sc14 supercharger can probably be had for less than $AU500... Course then comes the stuffing about with the jets in the carb.

 

[x-iled]

this is VERY VERY interesting... now tat my bike is gonna be alot heavier due to the mods i'm doing.. i'm kinda giving myself an excuse for more power.. hahahha..

but its the entire set up thats putting me off.. for a forced induction set up.. u will need forged pistons and con-rods too am i right?

coming to this .. if i could get an adapter to fit our oil filter case for an oil cooler mod... am i on the same track as you such that i can route the lines to go to the hydraulic supercharger system instead of the oil cooler or if possible somehow weave the oil filter component into the circuit... is this a possibel idea??

 

[OzDave]

Ahh well I can only speak from experience dealing with turbocharging a small capacity car engine, the particulars of a Vmax would need answers from people who've been there.

With car engines, in particular here I'm refering to a 4 cylinder 2 litre SR20DE block, you can safely go to about 7 Psi before needing to crack the block. It's basically a battle against detonation, the higher the original compression in the cylinder, generally speaking, the less boost its willing to accept. There are ways around it, cooling charge air temp etc. but the lower the cylinder compression the more boost you can feed in.

So regarding needing forgies in a Vmax it'd really depend on the compression ratio, I'd guess that the engine should be able to handle a few psi before needing to go internal, but if you wanted big numbers from forced induction then yeah, probably need to rebuild it.

Matter or fact I do have an oil relocator kit spare that could be used, would just need to make an adaptor for the Vmax filter cover... but I'm hesitant. Could cause problems if the oil froths up or over heats and denatures, plus putting extra strain on the oil circuit. Could end badly if it fails and the engine runs without lube before shutting down. With no figures about what the oil pump puts out and how robust it is I'm tempted to just focus on a standalone hydraulic system.

Not as elegant as simply running two pipes up from the oil filter, but would allow ya ta just focus on the hydraulics and the supercharger rather than having to worry about the side-effects to the lube system as well. That said its already a left field idea, when you've already gone that far why stop!

 

[adambweird]

Not sure if this would point you in any right direction, but I've seen 2WD setups on bikes with the front tire being driven hydrostatically. I would think that parts of that system could be used for some guidance on a supercharger system. I think the setup is made by Ohlins, don't quote me on it though. I do know that it works quite well and has allowed 100 mph on sand with the system on a sportbike.

Could really go off the deep end and design one that could power both a 2WD setup and a supercharger so traction issues could about be eliminated! That would be one hell of a ride on a built 200 hp motor!

 

[Rusty McNeil]

One of the oil pump gears is plastic, both of them if you've done an HD oiler mod.
I wouldn't put the extra load of a hydrostatic system engine oil driven system on that gear train.
Plus hydro heats the shit out of its fluid medium, requiring cooling means, lots of bulky equipment.

Separate pump? Like PS pump?
I'm thinking parasitic losses, coolers to keep the fluid from boiling, all the associated hoses and weight etc would really make it less feasible than a simple belt.

Coolant system is a centrifugal device, would never make the pressure needed. Gotta have PD pump to drive a hydro of any sort.

Stock engine, stock internals in todays typical normally aspirated car engines as stated by someone else earlier, about 7psi is max with something in place to provide excellent detonation control, timing retard in lean something or the other. That's my experience with cars,
No idea what a Vmax can take tho