I've been doing some research regarding more power. I know the best money spent to make the car faster is taking the nut behind the wheel to a driving school.

So, now that I got that out of the way. I was looking at an Eaton blower that a friend is installing into a honda. Well, the next size up should flow what we need for an M3. This charger shouldn't need intercooling and should be a pretty compact package. So have any of you done this or seen somebody with one?

Downing Atlanta has a kit for the M42 / M44 318's, which is supposedly a very nice quality setup. The biggest benefit is that it's SC makes maximum boost by about 2500 rpms, rather than the typical one that only makes max boost near redline.

Haven't heard of anything like that for the M's...

DA gave up on their efforts to produce a kit for 6 cyl bimmers.

A roots blower is exactly what this car needs! It severely lacks pwr/trq down low and the eaton would give it just that! Sometimes I go power hungry and miss my 2001 Lightning, but the M3 is still fun to drive.

Originally posted by AFJm3
A roots blower is exactly what this car needs! It severely lacks pwr/trq down low and the eaton would give it just that! Sometimes I go power hungry and miss my 2001 Lightning, but the M3 is still fun to drive.

I think just the opposite. Our cars need more tq up high to produce more hp. The tq curve tends to tail off after 4k rpms. To me there seems to be plenty of tq for loafing around the city in your daily commute, but runs out of breath on the track above 5k rpms.

But, it's all relative. I've never driven a Lightning.

I'm just exploring alternatives. The roots would give you the extra oomph but a centrifugal blower would make up up top. Then again a turbo would do the same. So, I'm at a crossroads again. After looking more closely frayed was right about the torque curve. It needs to be flattened out so you get that continued pull up top. I'm going to look into the turbo option and the centrifugal blower option.

A question about the centrifugal blower setup: Are they selling with a blow off valve or a recirculate valve?

I believe all blower kits on the market use compressor bypass valves; not sure on the details about how the valving works, or precisely how it compares to other types of plumbing, but my understanding is that boost is bypassed until your foot is in it. In other words, the blower is vented to ambient until a vacuum is created by getting on the throttle.

Blow off valves, I think, operate in a much different manner. Venting the pressurized intake charge to ambient at a preset upper threshold.

Any of you forced induction guys feel free to correct/clarify.

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On a sidenote, as you compare boost characteristics b/t centrifugal blowers and turbos, bear in mind that a centrifugal blower will only make their rated boost (eg, 7psi) at max rpm, while turbo's can spool up and make full boost much lower in the rpm band, around 4k. This is why turbo kits offer such a robust midrange pull as contrasted against blowers.

With either form of forced induction, the thermodynamic laws are the same, and turbo and contrifugal supercharger compressors have nearly identical thermodynamic efficiency. Cooling the intake charge with either system is pretty imporatant for safe engine operation. Most turbos come with some sort of intercooler, but blowers do not.

There's tons more info in the archives on these subjects.

Jeff

Hmm, on a similar note to an Eaton blower, there are lysholm blowers which are similar to roots blowers, but have an 80% efficiency to them, too bad they're loud as SHITE.

I think the biggest problem would be where to put them on our cars. There really isn't much room for one of those big boxes and the plumbing involved in it.

thanks guys, I'm going to do some more research on this topic.

Originally posted by frayed
I believe all blower kits on the market use compressor bypass valves; not sure on the details about how the valving works, or precisely how it compares to other types of plumbing, but my understanding is that boost is bypassed until your foot is in it. In other words, the blower is vented to ambient until a vacuum is created by getting on the throttle.

Blow off valves, I think, operate in a much different manner. Venting the pressurized intake charge to ambient at a preset upper threshold.

Any of you forced induction guys feel free to correct/clarify.

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Frayed is correct here. My dad and I installed an eaton blower on his miata. It uses a bypass valve which closes up when you get your foot into it. The rest of the time the air goes around the supercharger and into the engine. So... it doesn't stress the engine as much and you still get great gas mileage.

They really do produce a mound of power down low. Boost comes on full at about 2,500 - 3,000 rpm. Exactly what the car needed.

Originally posted by Rook

I think the biggest problem would be where to put them on our cars. There really isn't much room for one of those big boxes and the plumbing involved in it.


That is a problem with our cars. It does take up quite a bit of room....

http://www.andyphilpott.com/images/car1.jpg

You'd have to run some sort of manifold from the charger to the intake manifold. And get the flow meter in front of the whole works.

I think that it might not clear the shock tower.....

here's a side view

http://www.andyphilpott.com/images/car6.jpg

I posted this before, but if you haven't seen ithttp://www.fastlane.com.au/Custom_Shed/BoomerBeemer.htm

I always thought someone should develp something like in that link. Take out the stock manifold and stick a blower right there. Dont the DA chargers for 318's do that?

that's an interesting setup.

While I don't want to go too far with promises, I have been working on a positive displacement SC kit for E36's for a little while. I have spent over a year doing research and sizing calculations trying to completely understand the engineering side of things.

At my current state, I have an extra engine sitting in my garage, some brackets in mock-up, a modified intake manifold in the works, and have already worked out how I am going to manage fuel and timing control.

I am fitting a Lysholm compressor to get the most out of the positive displacement pressure charateristics, while maximizing efficiency.

My current plan is to provide a kit where intercooling is not optional, but is standard. I am hoping to have it working on my car in late spring/early summer. I'd like to do it faster, but I have a full-time job and 3 kids...

I already have a 95 and 97/98 M3 semi-lined up for installs once I get my own 325is sorted out.

I plan to do whatever I need to do to make this work. However, I make absolutely no promises yet on whether I will make it worth well enough for "mass" sale, and/or when I will get it done.

I can tell you that in the process of working out the location and packaging of the compressor and the system has already taken an incredible amount of effort, and I am only part way through. I keep telling myself that the problems I am having should make it clear to me why it hasn't been done already (save for the aussie). However, that has just made me more motivated to make it work!!!!

I'm guessing that there is probably enough interest to allow me to sell a few kits when I am done and recoup some of my development costs? I know that for what I am spending I could have purchased an AA turbo kit installed, and that does not include my time!!! I think when I am finished it will give people another option that has the benefits of the existing SC kits (easy install, no "lag", etc), while giving near the power capability of the turbos. The turbo will still win the all-out horsepower war, but the PD SC will give a very different driving "feel".

Any thoughts?

Steve

my thoughts......

Wow, you are my idol. I wish I had the time and resources to do a project just like this one. It's been a dream of mine for quite awhile. Someday.......

I'm very interested in how you're going to cool the air after compressing it and before getting it into the engine.

Any pictures that you'd be willing to show? I can understand if not.

No pictures available yet, and if there were, I would probably not show them.

I am moving in the direction of a front mount air-air intercooler similar to the turbo car setup. How I am actually going to achieve that is an exercise left for the reader, until I complete my project and have the car running with dyno curves, etc....

Don't idolize me until/unless I get it to work!!! :D

:buttrock

Steve

hey you're working on what I someday will be doing as a career so I most certainly jealous

(can anybody else say they're this excited about their job?)

Sounds VERY interesting, I can't wait to see more.

Maybe you provide some light on this for me, which side is the supercharger mounted on? intake or exhaust side?

If you don't want to explain, I totally understand.