Eaton M45 Supercharger

Posted By: Anonymous

Eaton M45 Supercharger - 20/10/2006 10:45

I couldn't help but notice on Matt's reply in another thread that he'd supercharged his Coupe as well as turbo charging it.

I sent him a private email asking lots of questions and he gave me permission to quote his reply:

Quote:

Hi there John,

The Coupe is proof of our capability as tuners and a lot of tuning concepts and ideas and at no time would I recommend it to anybody to go to the extremes that we have gone on my car. Some of the modifications work very well and others are not as successful and probably not worth the money.

A full report on my car will follow and I will tell all, successes and failures, do’s and please don’t even consider that modification.

The SC conversion is marginal in terms of value for money, but we had to build it, you can even run the car with the option switched on or not since we use a linear lambda controller on the car which allows us to set target air/ fuel ratios and the computer compensates irrespective of what we are boosting. It will always keep the air/ fuel ratio inline with the target ratios.

We did not do the supercharger conversion to make more maximum power, but rather to make more power and torque low down in the RPM range where the TC suffers from turbo lag.

You could probably run the SC conversion on the standard 20VT setup with little impact on the existing fuel and ignition maps since you will not be producing more boost but rather more boost at a certain RPM level and the stock ECU should be able to adjust for the increase in air flow in the lower RPM ranges, but it would be worthwhile to check with Graham that modifies the 20VT chip. Just don't over do the SC boost

The SC option is completely reversible and I would recommend that you invest in the following components/ modifications before you attempt the SC conversion: (you could sell the 20VT one day and keep the components for your next project after you have returned the 20VT to standard spec. It is a one time investment.)

Programmable engine management allows you to unlock the potential of your modifications, without it you will always be limited by the standard ECU and its lack of flexibility. I use a KMS system and I can provide you with a base map if you need one. I am a dealer for KMS and if you are interested I can help you buy a unit at a good deal.

High capacity fuel pump – I recommend a Walbro 255lph HP pump, lots of suppliers in ebay and close to you in Canada.

High capacity fuel injectors – Talk to Rus at Marren Fuel Injection, but I think 780cc units will do the job www.injector,com You can get the Walbro pump from Marren as well.

Adjustable boost referenced fuel pressure regulator – Again talk to Rus and he will advise you, they have units that simply replace the standard Bosch unit on your car.

Next you will have to some plumbing, try to stick to aluminum and find someone that is excellent at Mig welding, replace all the boost pipes with Al units.

It maybe worthwhile upgrading to a GT28RS turbo units

Upgrade to a FMIC

Move the battery to the boot

If you can find a decent exhaust manifold, go for it

The Supercharger (Eaton M45) you can get from these guys on ebay, units are used but reconditioned, don’t pay more than US$500.00 including the exchange unit penalty. It comes supplied with a magnetic clutch pulley. Clicky

Get yourself a 76mm BMC Cone Filter.

If you cannot manufacture a bypass valve I recommend you buy one from ATP Turbo, they developed it for use as an exhaust diverter valve but it is universal in application. You will have to remanufacture the T piece from Aluminum if you are going that route on the boost pipes, any half decent machine shop should be able to it with their eyes closed.
Clicky
This is how it all comes together:
Air Flow Path
- Air enters the 76mm BMC Cone filter
- The air then passes through the Supercharger
- From the SC the compressed air is fed into the compressor housing of the TC
- The air passes through the TC and enters the FMIC
- From the FMIC the air enters the Inlet manifold through the throttle body

Things to manufacture:
- The SC inlet manifold
- The SC outlet manifold
- The SC mounting bracket, you just mount it where the aircon unit would have been mounted
- The SC should be mounted with the outlet manifold on the top side
- The bypass valve if you are not buying it
- The piece of boost pipe that connects the SC to the TC compressor side
- The boost pipe between the air filter and the SC

Setting it up:
- The SC pulley gets driven of the power steering pump pulley that used to drive the aircon pulley, it should fit the standard setup since it is only 185mm wide and I run a alloy double pass radiator that is thicker than the standard unit. I could be wrong
- The bypass valve opening to the air filter is closed to the air filter until boost pressure of 7 psi is produced by the TC and the SC.
- At this point a solenoid is pulsed by the ECU. (You can also pulse the solenoid to with a pressure switch or an output on a boost controller.)
- The solenoid will allow pressurized air form the inlet manifold to enter the actuator on the diverter valve which in turn will open the diverter valve so that air could be pulled from the less restrictive route from the air filter instead of the SC. (The TC will need more air than what the SC could deliver and will become restrictive in terms of air flow)
- You could choose to let the SC run and continue to provide boost or you could choose to switch the magnetic clutch pulley off by the same signal that opened the solenoid valve.

You are more than welcome to post my replay on the forum for comments, some of the other forum members would probably come up with some other questions that could proof worthwhile and I don’t mind some lively discussion.

I will post pics as soon as the car is in one piece again. We are busy with polishing, sand blasting and powder coating of parts and putting the finishing touches to the car.

More Info

I hope that I have shed some light on the topic, you could do this conversion with less money, works and hassle than what I put myself through, but that is me.

It sounds an interesting project for those long cold Canadian winter evenings!

I guess that you wouldn't need a special trigger from the ECU at 3500 rpm as all you are really interested in is generating boost earlier than before the turbo would normally spool up.

Therefore I was thinking of a pressure triggered switch to say switch off the supercharger via the magnetic pully at about 7psi (or whatever pressure would be needed to get the turbo spinning and take over) and also operate the bypass valve to allow air from the air filter to flow directly to the turbo charger's compressor wheel without going through the restrictive supercharger.

The bypass value on the supercharger would control the boost generated by the supercharger although it's not clear whether this could be operated via the same electronic boost controller that currently operates the turbos wastegate. You might need two electronic boost controllers which I guess would actually be easier to set up.

I'm not sure what's going to happen when you lift off or charge gear. I imagine the boost pressure from the turbo will drop and the supercharger pulley will engage again generating boost. This off course will be vented off via the dump valve but will be instantly available when you open the throttle again.

John

Posted By: JohnS

Re: Eaton M45 Supercharger - 20/10/2006 20:00

you could use the timing variator signal to switch off the supercharger as well. Some of the aftermarket chips use a lower 4000rpm setting.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 20/10/2006 20:07

JohnS great minds think alike as i was just about to suggest this

Im guessing you can get a supercharger with a clutch wheel like an aircon compressor and you could have it kick out then when it hits the variator point?

Posted By: Anonymous

Re: Eaton M45 Supercharger - 20/10/2006 21:03

Do you know if the front engine mount is different between a car with and without AC or whether the AC compressor is fitted to a separate bracket?

Thanks

John

Posted By: JohnS

Re: Eaton M45 Supercharger - 20/10/2006 21:25

Well I know you're a great mind with near 7000 posts...dunno about me tho...

Yes, you could use either positive or negative switching based on the variator signal (either way is easy to wire up). The variator signal is good for other reasons, because the variator stays on in part throttle (<70%) which means you get instantaneous power regardless.
I'd suggest that a geared up (important!) Rotrex centrifugal supercharger might be a better solution as it has a lower load-loss, and is more efficient than a conventional supercharger.

the whole engine mount (single unit ) is different and the alternator is different between aircon and non-aircon cars. I think it's quite a big job to switch mounts in-situ. I guess it may be physically possible but you'd have to measure up before trying. The reason the alternator is different is the adjustment for tension is on the aircon pump on aircon cars, whereas it is on the alternator on non aircon cars. Dunno if adjustable alternators are compatible with aircon - never looked.

There are a few other bits and bobs that also need changing as well.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 20/10/2006 22:21

It can be removed in situ, it's not a fun job but not technical just involved.

You can support the engine using a bottle style jack under the sump using a section of wood to spread the load. You have to remove the wheel and bits of the wheel arch liner to get to the belts. You have to remove the oil cooler and pipes, the power steering pump and pipes and the alternator. The bracket is held on with about 8 large bolts of different lengths (make sure you make a good note of where they came from), some hidden behind the powersteering pump. There are several oil flows etc.

John

Posted By: JohnS

Re: Eaton M45 Supercharger - 20/10/2006 22:25

I can imagine it'd be a pain. How long does it take roughly?

Not as much of a pain as trying to change the oil pump in situ though apparently

Posted By: Anonymous

Re: Eaton M45 Supercharger - 20/10/2006 22:46

it's not too bad. I had todo this to track down an oil leak from the oil filter connection and a mysterious water leak. It took me several days to dismantle as I worked out how to remove the various parts and taking my time. For example how to remove the pulley off the power steering pump (you can't get to the bolts behind the pump without taking off the pump and you can't remove the pump without removing the pulley first.

It only took a day to put back together. Could be done quicker but I missed one of the bolts and it was typically the one behind the power steering pump so the alternator and pump and belts had to be removed again.

I also had fun and games trying to get the oil cooler pipes to refit. The new downpipe H&S I'd fitted at the same time came over further than the old one and I had to try and bend the pipes slightly to get some clearance.

John

Posted By: Anonymous

Re: Eaton M45 Supercharger - 25/10/2006 10:36

Quote:

There are a few other bits and bobs that also need changing as well.

Do you know which other parts are different? How about the coolant hose that fits onto the engine block above the alternator on non A/C cars?

The belt is different but that's easy to replace and I'd fit a new one anyway.

Thanks

John

Posted By: JohnS

Re: Eaton M45 Supercharger - 25/10/2006 15:01

Non air-con cars have a different water rail. Not sure whether you can stick with the one you have though, as I think the difference is the pick-up point.
Obviously the pipe between the rail and reservoir is also different.

I changed my car from aircon to non-aircon ironically

Posted By: Anonymous

Re: Eaton M45 Supercharger - 25/10/2006 16:16

I had big plans too.

I planned to do this 2 years ago to my 20VT using exactly the same induction method. I looked into the Eaton M45 as they go for about £150 on e-bay but decided not to. I brought the supercharger Rotrex CP30-84. I was going to remove the aircon and the Rotrex fits perfect even came with a 5 toothed pulley with just a bracket needed making up. This supercharger uses its own oil system so no need to tape anywhere. Any how never got round to starting due to lack of time and funds so I sold the supercharger on e-bay.

Here our some pics. The type R is now 320BHP at the wheels with just the supercharger and intercooler fitted everything else is box standard.

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/Standard/Rotrex1.jpg

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/Standard/Rotrex2.jpg

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/Standard/Rotrex3.jpg

http://jayman.bulldoghome.com/photos/bdres/jayman_bulldoghome_com/Standard/Rotrex4.jpg

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 11:52

After a bit of background reading there are three types of supercharger, roots, twin screw and centrifugal.

Roots
These are the oldest design and the least efficient. They tend to be large and heavy. They don't compress the air only blow it in discrete bursts. However they are most suitable for low down power.

Centrifugal
Just like half of a turbo, the compressor side. These are the most efficient and are usually small and lightweight. They have a distinctive whine. However they tend to work like a turbocharger in that they only really get going when the turbine spins at about 50,000-60,000 rpm. Thus they will produce the most boost at the upper end of the engine rpm. The amount of boost is equal to the square of the impeller speed.

Twin Screw
These fit somewhere between the two. It compresses air using twin conical screws. There is only a small tolerance on the gap between the lobes making them expensive to manufacture. They make a distinctive whine and are more efficient than the roots but not as efficient as the centrifugal. Typically the engine is at between 2000 and 2400 rpm when full boost is achieved.

Cheers

John

Posted By: JohnS

Re: Eaton M45 Supercharger - 26/10/2006 12:30

On the centrifugal charger front, the way they actually behave depends also on how you gear them. So you could get a small centrifugal charger but geared up so that it is making good power at low engine revs - the chargers input rpm doesn't have to be the same as the engines. The reason why they usually make most power at the top end is primarily because they are not normally paired with a turbocharger.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 20:40

That makes sense but I'd have to be careful to disengage it at the upper end of the engine rpm range otherwise it'll probably over rev the turbine. I'm not sure one would fit in the space available though, a twin screw or roots shape one would more likely fit.

I'll have a dig around and try and find some dimensions. At least with a centrifugal one it typically has standard hose style inlet and outlet where as the other two tend to have custom shaped outlets.

John

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 21:21

To disengage at higher rpm on an Eaton (Rootes) you could easily use the solenoid controlled bypass valve, as on this Eaton diagram (It's usually used to bypass at low throttle settings)

I don't know any cars with both blower and turbo, but it is very common on Volvo marine diesels, perhaps trucks too?

Posted By: JohnS

Re: Eaton M45 Supercharger - 26/10/2006 21:31

aren't most of the Eaton charger twin-screw?

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 21:43

Quote:

I don't know any cars with both blower and turbo, but it is very common on Volvo marine diesels, perhaps trucks too?

Don't forget about the Bugatti Veyron

The Rotrex is a centrifugal type and will fit perfect. As John said you need to get the right pulley in order for it to produce boost where you want it. Plus the noise is beautiful.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 21:50

Yes they appear so, although every reference I've found recently refers to Eaton's as 'Rootes-type'

The boost must be available from lower than 2000 rpm though hence the need for that bypass valve at low rpm/part throttle settings on stock instalations.

Posted By: pinin_prestatyn

Re: Eaton M45 Supercharger - 26/10/2006 22:03

Bugatti Veyron has four turbos... but didn't think it had a supercharger?

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 22:10

Quote:

but didn't think it had a supercharger?

Your right, it has two

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 22:13

Quote:

aren't most of the Eaton charger twin-screw?

Don't think so, all the pictures I've seen including the link above indicate a roots style.

A twin screw supercharger has a pair of very distintive worm screws rather than three lobes along the length of the shafts.

Good old How Stuff Works website

John

Posted By: Anonymous

Re: Eaton M45 Supercharger - 26/10/2006 22:17

Not trying to pull anyone’s leg but a little birdie told me that the W16 engine has two small superchargers in addition to the four turbo’s in order to reduce lag but Bugatti hadn’t released this info with their spec sheet. Whether this is true or not I am unsure but what I do know is. Isn’t it strange you can’t find a real picture of the engine with the angle showing the timing belt? Most of the pics are computer generated. The only real one shows the engine from a frontal view. I’m not trying to start a conspiry theory but it is interesting stuff.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 27/10/2006 11:43

Lancia used both a turbo and supercharger in their Delta S4, and it seemed to work out quite well for them.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 27/10/2006 20:55

The new VW Golf uses both as well.

Posted By: Anonymous

Re: Eaton M45 Supercharger - 28/10/2006 14:53

Toyota produced a 145bhp 1.6 16v mk1 MR2 supercharger(jdm only

), this was happily modded to produce 180bhp with a pulley wheel change, and then the happy guys at HKS brought out a turbo kit to deliver a 'twincharger' this was reportedly 250bhp plus territory and while I was in the IMOC (International MR2 Owners Club) there was a member in the states who had one running 350bhp - from a 1.6

which he posted his drag times at 11.4s on the QUARTER mile. That car weighs onlt 1090kg, and mid-engine helps the take-off.
There must be some real potential in the twincharging route for the coop too!

Posted By: Anonymous

Re: Eaton M45 Supercharger - 28/10/2006 16:06

Just a slight space issue and a decent mainfold to house them. Would be good if someone could develop it. I think superchanging would be better as you could have a single big turbo and the charger should eliminate the lag. I'm waiting to see Matt's coupe's dyno run results.