[Andy M]

Already taken into account fitment for all E9X models. Measured a ton of cars for fitment already. The only thing that changes is bolt hole configurations for all E9X. I won't know for sure if it will work though until my second prototype is done production and then I can actually get it installed on various models.

Might not work on the Mtech bumper with the OEM diffuser if the bolt holes aren't there. It needs something to be anchored on. I'll need to look at several cars with the M-Tech package and diffuser to know for sure how to mount it on but from what I've seen, it looks as though the anchor point has been deleted (might be due to the way some people are installing it? Not sure on that...)

Big difference is 335 vs non-335. LCI and non-LCI have the same bolt configuration so fitment will work regardless of LCI or non-LCI. The current design has three main sections: center plate and side plate for a total of 8 fins. The location of the non-turbo pipes means only the center plate with 4 fins can be used. The two biggest fins are located on the center plate anyway and if it's for cosmetic purposes, the center plate fins are the most noticible.

I've designed two variations for the fins too - one to work with the CF deflector and one to work without it. Lots of hours spent doing the design!

As for testing the function, I'll need to set up a set of load cells under the tires in a wind tunnel. Might be overly costly at this point unfortunately so I don't think I can get any numbers to show what kind of downforce I might be able to generate. Also, depending on the overall ride height, the downforce would change.

[triggz]

sweet!

[Andy M]

Originally Posted by Havok_2011

No worries, he is working on an E92 version as well.

Thanks. And yes, should work on E92 335 and 328 LCI and non-LCI. Just M-Tech seems to be an issue now based on how it's installed. Considering maybe building some sort of support bracket that will mount directly to the frame. However, with every extra piece of hardware used to mount it, the cost will go up.

[gian335]

Originally Posted by Andy M

Thanks. And yes, should work on E92 335 and 328 LCI and non-LCI. Just M-Tech seems to be an issue now based on how it's installed. Considering maybe building some sort of support bracket that will mount directly to the frame. However, with every extra piece of hardware used to mount it, the cost will go up.

andy, there are tons of us with mtech rears,plus i would definately be able to help, if you need a test car or anything. i think doing one for the mtech would be worth it.

great job so far

[Andy M]

Originally Posted by gian335

andy, there are tons of us with mtech rears,plus i would definately be able to help, if you need a test car or anything. i think doing one for the mtech would be worth it.

great job so far

Thanks. I basically need to look at a few cars and see what the setup is like for their M-tech bumper and diffuser setup. I can probably design some struts that will attach to the actual frame of the car for support.

I'll take it one step at a time though. Waiting to get it fabricated at the factory and then sent to me for installation on my vehicle as the test mule.

[jxu]

Interested!

[Andy M]

Just out of curiosity, how many would be interested in just the CF piece?

Been negotiating with a manufacturing supplier for my CF and if I put in a larger order in at the start of manufacturing, I can probably offer the CF piece by itself for half if not less of the cost it would normally be (as in during regular production - bulk manufacturing is always cheaper).

I'm thinking in the magnitude of $250 to $450 (depending on group buy size?)

[gian335]

id be interested, only for e92 mtech rear however. And i know ur testing it on the regular rear bumpers.

[Tee212]

some quads + diff pls for e92 thanks!

[Andy M]

In all honesty, I don't think the CF piece would look good at all on the mtech bumper. I don't mind trying to get the CF piece to fit but I think it wouldn't look great at all...

The CF piece is more of an option for non-mtech who don't have mtech. I'm thinking that the mtech of the whole diffuser package would just be the fins minus the CF piece since aesthetically it doesn't look so great... (I COULD make it work but I'm not sure how great it would look).

[engotski]

Def interested in this as well. E92 328i

[turugara]

If this really worked out, I'm sure some people would be interested even if function > form

[Andy M]

Just an update on this...

Nothing will be happening for a bit (see this thread: http://www.e90post.com/forums/showthread.php?t=565619).

I'm already looking at making some improvements to the existing design. Already considering doing a full smooth underbody design. I'll be designing it so that it takes air from the front, accelerates it using the venturi effect in order to cool the exhaust system (since our BMW's are designed for air-cooled exhaust systems). It'll also drop the bottom of the car by about 1" so the ground effect gain from it would be magnified. Unfortunately it won't work with cars that are slammed but if you're slammed, you won't need this anyway (because the front of the car will act as an air dam anyway).

Oh and it'll be all done as an add-on so it'll have to work with the diffuser I have designed now (so basically no waste if someone wants more performance later on). Won't be doing it in CF, likely PET and high performance aluminum again (for cost and also durability and heat dissapation).

[gian335]

sry to hear bout ur accident. european auto body is a good shop, ur car will be like new.

I think PET and high performance aluminum is much better for production. Keep up the good work andy

[johnsonz1122]

i suppose this will work on e90 lci non 335i. rite? keep us update!

[turugara]

Keep up the good work! Excited to see this developing.

[Andy M]

There was enough interest so I'm trying to get this to work on all E9X cars.

Right now, until my car is back and I can take measurements, I'm working on a full smooth underbody kit that will be integrated with the diffuser. (that's for my car lol). What I've already designed for the rear diffuser will fit into it so you should be able to choose to what extent do you want to do the aero kit for. (just the back or the whole underbody).

The underbody thing is a lot harder than I had thought at first because I have to design it so the air also cools the exhaust. I'm hoping once it's done, it'll actually cool the exhaust system at high speeds a lot better than not having it on... (and yes, I'm at least having a lot of fun doing this! Finally using my degree to its fullest capacity now!)

[jwise36]

Originally Posted by Andy M

There was enough interest so I'm trying to get this to work on all E9X cars.

Right now, until my car is back and I can take measurements, I'm working on a full smooth underbody kit that will be integrated with the diffuser. (that's for my car lol). What I've already designed for the rear diffuser will fit into it so you should be able to choose to what extent do you want to do the aero kit for. (just the back or the whole underbody).

The underbody thing is a lot harder than I had thought at first because I have to design it so the air also cools the exhaust. I'm hoping once it's done, it'll actually cool the exhaust system at high speeds a lot better than not having it on... (and yes, I'm at least having a lot of fun doing this! Finally using my degree to its fullest capacity now!)

first of all i would like to thank you for doing this, ive been looking for an option like this for some time.
i would be very interested if you need a tester car id be happy to offer mine up its a e90 lci 328xi

hope all is well after the accident, its a terrible feeling but it should look as good as new!

have a good one

[turugara]

How's the car looking after the fender bender?

[E90MCF]

Hope all is well Andy.

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[dzenno]

You'll need a wind tunnel and thermal probes to prove it works...how do you intend to do that? Sounds very interesting on paper though, good luck

[Andy M]

Actually what's interesting is the accident didn't take out the bumper at all. Had Ventureshield on there to protect it from minor bumper hits in parking lots (because no one here will leave a note if they hit you, especially if it's an expensive car). Bumper didn't even have a scratch from the impact. Ventureshield was completely taken out though so I can attest to the fact that it works for a 100 kmph impact!!

Anyway just finishing up the fabrication drawings for the factory.

Decided not to go with the smooth underbody. BMW has already installed an underbody panel system to smooth out the underside and the only exposed areas are the exhaust system and the rear differential. So my underbody will cover the rear differential area and rear bumper area which builds up a lot of turbulence. It'll keep the costs lower again.

Designing an optional frame system with fins though to channel the air through the entire underbody to the back.

And yes, testing it will be difficult. Everyone's setup is different and it depends a lot on the ground clearance too (which changes depending if you have your car lowered or not). Also, the main issue is finding a wind tunnel big enough to put a whole car in... there is a wind tunnel in London (http://www.vigyan.com/capabilities/wind-tunnel1.shtml) however the test section is 3'x4' which is way too small for a full-scale test. Most wind tunnels are usually pretty small because they're used to test a small section of something like an airplane wing and not really for a whole car. When I was in school, we would build scale models of bridges to test the hydraulic effects on the piers and then factor our results for scale.

So...what I was thinking of doing actually is trying it on a 1:18 scale model. I'll build a 1:18 scale mockup and just tape it onto a 1:18 scale model. I'll use load gauges to measure the change in force on the wheels. If I had access to a full scale wind tunnel, my setup will be the same (load cells under the wheels).