High speed flanged coupling required

[JohnC]

Not exactly a GT40 question, but is related to power transmission.

I'm looking for a high speed coupling to mate two 5/8" or 3/4" half shafts together, and it would be equipped with a mounting flange that a gear or pulley could bolt to.

Has to be good for 10K rpm, and able to transmit 30-40 lb-ft of torque.

I've had a look around the karting supply houses without any luck, but if anyone here is into shifter karts, etc. perhaps you know of something?

TIA

 

[Scott Calabro]

Cribbj,

Google "Thomas Coupling"

Not cheap by any means but they are used to couple helicopter driveshafts that can turn in excess of 20k rpm and can handle lots of TQ.

If nothing else you will find them interesting!

S

 

[JohnC]

Thanks Scott, found one that is "almost" right, and will be contacting them today to see if it's adaptable.

John

 

[Ryan]

What are you trying to do with this, I would be interested to see any pics of the proposed coupling concept!!!

This just sounds interesting.

 

[JohnC]

Ryan at the risk of incurring Ron's wrath for posting about engines in the transaxle area, I'm building a triple supercharger setup for an inline six cylinder engine. To drive these superchargers, I need a jackshaft, and in order to change the cogged drive belts in the future, the jackshaft has to be split, hence the high speed coupling.

Below are a couple of pics of the system mounted on the engine's head. Next step is to mount the system on the engine block, brace it very well, and fabricate the drive system.

Those are Suzuki motorcycle TB's, and while they and the trumpets are very sexy, they add too much width to the system, so after we run it in on an engine dyno and see how it responds, they'll come off, and a plenum with single TB will be built so it can be fit into a car.

 

[Roark_John]

It would be alot easier (and cheaper) to simply build one shaft that can drive all three superchargers sequentially. It's a relatively simple matter to align them on one axis and either drive with an offset jackshaft and pullies to each unit, or simply mount them back to front with a continuous shaft running through each case (one precision shaft replacing each individual unit shaft), to be driven by one belt.

for example:

[_____]- [_____]- [_____]-
______^_______^______^___

with belts running from the lower jackshaft and pullies spaced accordingly, running individual units

or

[_____]--[_____]--[_____]--

one continuous shaft running all three units at one

 

[JohnC]

Thanks Wyoming; your first schematic is actually how I'd planned to drive them, however the drive shaft would have one split in the middle. I understand this method has already been done successfully in Australia on either a 4 or inline 6 cylinder motor.

I haven't investigated trying to run a common shaft between the three, but to me, that just doesn't seem very cheap or very easy, considering the mods that would be required to the cases. I'll pop the side covers and investigate further, though.

 

[Ron Earp]

o drive these superchargers, I need a jackshaft, and in order to change the cogged drive belts in the future, the jackshaft has to be split, hence the high speed coupling.

Ok ok, you can post here IF you can answer the following: who makes those little blowers, what displacement are they, what type, where do you get them, how much do they cost, and what were they used for originally? :!blank:

Thought about a little plenum between the blowers and the head to put a custom intercooler?

Oh, and what head is that?

 

[JohnC]

Ron, the blowers are made by Aisin of Japan, their model number is AMR500, and each one displaces 500cc's. They also make a smaller one called the AMR300, which is a 300cc blower, and a slightly larger one called the EK10, which is 750cc. Max RPM is 15K for all.

These were originally packaged on several very small Nissans and Mazda's, however Aisin USA has no information on them whatsoever. If you Google on Aisin AMR500, you'll soon know as much as I do about them.

There's a build thread on this project over on the Lextreme website. I'm calling it The 2JZ-GZTE Project

I bought the superchargers from a fellow in San Antonio who's in the import/export business and gets them from Yahoo Japan, and other sources, and then resells them on eBay here in the USA. Going price is around $650 per copy, however he may make a discount for buying 2 or 3 at a time. If you do a search on eBay for "mini supercharger" or "Aisin supercharger" you should find his ads.

There's already a little plenum between the blowers and the head, and it might be a good place for a couple of Laminova tubes, however there's a lot of bracing, injector bungs, and other claptrap inside the plenum, so getting some finned tubes in there would be a chore. I'd planned to inject methanol/water at that point to keep the charge air cool and ward off the dreaded det devil. I also intend to keep the OEM Suzuki injectors to inject a bit of methanol directly into the chargers to keep them cool as well.

This is the first step of an eventual turbosupercharger project, however I don't intend to compound the boost from both the turbo and these SC's. Rather, I'm trying to size the turbocharger so that it doesn't come on boost before 4000 or 4500, so that the SC's will be working in their happy power band down low, and the turbo in its happy band up high. I'll control boost by judicious use of the SC recycle valves and the turbo's wastegate.

Oh, and that's a Toyota Supra 2JZ-GTE head...

 

[Ron Earp]

Awesome! I like it and really appreciate the info. That last small blower I'd had on hand for a project that I didn't do was a Sims and Rohm unit. Very interesting and I hope you'll keep up with it in the engine section, inline sixes are cool.

Normally I'd ask a lot of questions like why not fit a 3L whipple, KB, Roots, etc. but I won't because I like the three little blowers. Neat!

 

[Jac Mac]

Google 'Falk Steelflex Grid Couplings' , ' Tsubaki Chain Couplings' & also 'Rathi Spider Couplings'.

The chain coupling looks primitive but we have run that sort to direct couple the crank to shaft on 200hp Hydroplanes @ over 8k with a prop shaft that twisted like a snake with only the bottom blade in the water. Have seen twin engine dragsters coupling two V8's inline with similar.

 

[JohnC]

Ron, the conventional blowers that you mention just don't "package" well for an inline six cylinder engine. Trying to fit a single blower on an inline six requires some very tricky manifolding, and then of course, everything starts growing sideways, and you soon run out of room in the engine bay. Some people have packaged centrifugal blowers on sixes, however I don't see the point in that. A centrifugal is basically just a belt driven turbo and has a power curve similar to a turbo. Most sixes on the market already have well developed turbo solutions, so why put a centrifugal on that does the same thing, and robs more power from the engine than a turbo?

The only other little blower that could have been interesting was the M45 Eaton. A pair of those probably could have done what I'm doing with the three small Aisins, and perhaps could have been made even more compact, since their intakes are at the rear, rather than being straight through like the Aisin.

But, I really like these little Aisins, and frankly just wanted to do a project with them!

JacMac, thanks for the recommendation on the chain coupling. I hadn't considered those initially but will give them a 2nd look.

 

[Ryan]

Wow. Very trick. I like. I like alot. Very impressive, and yes very cool. Thanks for those part #'s and detailed info, that might become a future option for a chopped/superbike/drag cycle I have been dreaming of building up for a while.

Keep it up MacGyver, well done.

 

[Roark_John]

Thanks Wyoming; your first schematic is actually how I'd planned to drive them, however the drive shaft would have one split in the middle. I understand this method has already been done successfully in Australia on either a 4 or inline 6 cylinder motor.

I haven't investigated trying to run a common shaft between the three, but to me, that just doesn't seem very cheap or very easy, considering the mods that would be required to the cases. I'll pop the side covers and investigate further, though.

Maybe I'm blind to the problem, but why would you use a two piece jackshaft with a coupling? KISS is always the way to go.

Having the main cases modified for a throughshaft is pretty trivial compared to properly engineering a split jackshaft and having all those extra belts and pullies spinning away near the injection units.

Surely the price to have a competent machinist modify the cases to accept throughshafts and seals is inline with or less than that fancy jackshaft coupling you were eyeballing. Not to mention safer, less cluttered looking and far less complicated. Just my $0.02