OBR engine specs are on the wall poster in this pic, but the resolution is just low enough that you can't read it

http://a6.sphotos.ak.fbcdn.net...979_1332684962_n.jpg

It will also be interesting to see, how the AMG teams do in design, since this will determine, if AMG did their work and just gave them a plug & play solution or if the teams really designed the motor on their own and just used resources provided by AMG.
I think this approach is very interesting on one side, but also very difficult to judge who did the real work on the other side.

Fantomas

Well, even if they did only little work on the engine (as far as I know, there are a lot of Karlsruhe students at AMG to do they degree thesis) then they aren't "worse" than any other team which is using a standard bike engine.

Sure they wouldn't get credit for the engine but so far there aren't many teams out there who did it and would crush them in the Design event.

They probably are getting a really nice engine, that's what counts.

There are some Electric cars with own motors of course but that's another level I guess...

quote:

Originally posted by mech5496:
Ian, that might be because the engine is developed by 2 teams with AMG. Having suspension pickups (and chassis mounts) integrated, basically means that both teams will share rear halves of the car....

I agree that forcing an exact suspension geometry onto a team might be too much, but I see no evidence of ANY load-bearing mounts on those pictures. In mainstream motorsport it's normal for a tranaxle from Hewland, Xtrac, Ricardo etc. to have load-bearing mounts for dampers, rockers and suspension links. The rocker geometry & the exact design of wishbone clevises will be up to the chassis supplier, so they still have control of the suspension geometry, within the boundaries set up by the load-paths through the structure of the transaxle.

I still think this is a missed opportunity, as it appears to be an entirely un-stressed engine & transaxle, so the teams have to duplicate structure uneccesarily. I'd like to have seen a twin cylinder version of this:

http://dot.etec.wwu.edu/fsae/v30/v30pics.html

Regards, Ian

quote:

Originally posted by mech5496:
http://fahrzeugtechnik.fh-joan...-Joanneum-Racing.pdf

Two comments:

1. On page 21 is a decision matrix justifying the choice of a Line-2 engine over some alternatives (L1, V2, & F2). Interestingly the single (L1) wins almost every category except for "Leistung" (Power?). The L2 gets maximum of 25 points here, while the single gets 0 (!), so just misses out.

This seems a bit odd, given my earlier example of the 1970s Can-Am Porsche 917 with its air-cooled turbo'ed flat-12 that delivered 125hp from EACH of its 450cc cylinders. (Seems like some "creative" decision matrixing here... .)

2. On page 44 is the Zugkraftdiagramm (Tractive Force Diagram?). To me, this shows the irrelevance of a multi-speed gearbox when you have a reasonably powerful engine.

Z

Just want to through in that the AMG engine isn't running until now as far as I know. All numbers are results of simulations.
There has been quite a similar project in the past - remember the Mahle engine? We in Stuttgart do. I don't wish anybody bad luck, but I'm more than sceptic. People in big companies very often think that it can't be that hard to build something which is far better as anything else in a competition where just stupid students take part in.
We also were part of the team choosing process and there were a couple of points which led to the decision that our team won't seriously apply for the project. The real reason for turbocharging is, that the new AMGs will all be turbocharged...

As said - my personal opinion. Prove me wrong.

Is anyone else having trouble downloading the pdf? I talked to KIT at FSAE-MI about the engine and would really like to know more. If it's small enough to attach to an email, could someone shoot it my way? It would be much appreciated.

I wouldn't mind comparing it to the Mahle development presentation I recently found in our office

You got pm.

While discussing this new AMG engine earlier in out garage, myself and another team member got to thinking. How does this work per rule B8.7.1

quote:

B8.7.1 Turbochargers or superchargers are allowed if the competition team designs the application. Engines that have been designed for and originally come equipped with a turbocharger are not allowed to compete with the turbo installed.

This engine has clearly been designed with a turbocharger.

To be honest, the intent of that rule (IMO) is to prevent a team from buying a canned engine that will easily outperform everyone else without really understanding the system they are using.

There are few teams that know as much about turbocharging in FSAE cars as the Joanneum Graz team. They know what they are doing, and they more that likely did quite a bit of engineering with the AMG guys over their system, especially since it looks similar to the layouts they have run in the past.

quote:

Originally posted by whiltebeitel:
There are few teams that know as much about turbocharging in FSAE cars as the Joanneum Graz team. They know what they are doing, and they more that likely did quite a bit of engineering with the AMG guys over their system, especially since it looks similar to the layouts they have run in the past.

Which makes it even more baffling that the single-cylinder concept received zero points for power on their decision matrix. The matrix shows that the single-cylinder was the clear winner.

For those who are better with the German language: in their comparison which shows the 360 degree firing order to make more power than the 180/540 degree firing order, did they expand the intake plenum (intercooler tank) volume to compensate for the uneven firing order? I would not have expected the difference in power to be that great, but trying to minimize intake plenum volume would do that. The Rotax 600 ACE 180 degree parallel twin revs to 7500 rpm without balance shafts and its rotating assembly would have been my first choice for this project.

This message has been edited. Last edited by: Mbirt,

quote:

Originally posted by Mbirt:
Is anyone else having trouble downloading the pdf?

Yeah, for some reason I can't open it here either. I thought it was because I was on a university computer, but couldn't open it a home either.

Could someone possibly mail it to me?

Thanks,

Ed

ed.....you got PM...

Sharath

I’ve been working as a new product development engineer for about 15 years now and I can tell you that the subject of how exactly to choose feature objectively is the subject of quite a bit of debate at all levels of the 3 places I’ve done this job.

The company I work for is all about the 6 sigma methods these days and my black belt project was finding a way to use a DOE in a double blind customer preference study so we could figure out just WTF the customer actually wants because when you just ask them they lie. They don’t lie intentionally, but they tell you what they think the right answer is, or what they try to do instead of what they actually do and that leads to putting the wrong features into the product…..and getting the product wrong isn’t tolerated well where I currently work, we are #1 in our market segment and intend to stay #1

Anyway, there are a lot of pages with a lot of good ideas in this thread but it comment caught my eye as a problem.

quote:

Originally posted by Z:

1...... The L2 gets maximum of 25 points here, while the single gets 0 (!), so just misses out.

Generally, with whatever tool you create for ranking, a 0 in any category that was important enough to be on the list should lead to an automatic rejection of the concept…..but a zero shouldn’t have been given there either. It’s easy to create a comparison matrix, then use it as a tool to justify a decision you’ve already made in our mind and it appears that is what was done here.

Scaling is really hard. What I find normally works best is a log or exponential scale of some kind. I like stuff the is 1-10 so for say power, a 1 might be enough hp to get the car through the events….maybe 3-5hp, something that gets you in the game is a 5, say 45hp?, a 7 would be a hp number that is truly competitive, 65hp maybe?, 8 = 70hp, 9 = 85hp, 10 for anything over say 75 because that is about the practical limit and more just spins the tires anyway. The goal is always to get resolution in the area of interest. If the goal is also excellence than another rule that says on certain key issues a score under 5 or 6 or 7 is a veto for the concept.

This is how I do it, hope the ideas are helpful.

Thanks for the forward.
Ed

quote:

Originally posted by Mbirt:
Which makes it even more baffling that the single-cylinder concept received zero points for power on their decision matrix. The matrix shows that the single-cylinder was the clear winner.

That's the point of these decision matrices. By playing with the numbers you will get any answer you want. I already mentioned that from the beginning AMG insisted on turbocharging...

I can't find the document anymore. If you send it to me, I can translate the part you mentioned.

quote:

Originally posted by Bemo:

That's the point of these decision matrices. By playing with the numbers you will get any answer you want. I already mentioned that from the beginning AMG insisted on turbocharging...

That is ALWAYS the problem with this type of exercise. There is simply no such thing as an “unbiased” opinion or rating.

The first pass at any model of anything will have the biases of the person who created it build into it which is why the validation of the model is so important……an unvalidated model is just the opinion of the person who created the model, nothing more. It looks like more because there is math in it…… but it’s all based on assumptions and until a validation is performed you have absolutely no way of know if the assumptions are correct or not or whether the model is complete or not.

Validations suck to do, there is no other way to put it, they absolutely suck….but without a validation you have nothing. You don’t have a useable engine selection matrix, you don’t have a test method that you can use to make decisions, you have nothing but a guess.

quote:

Originally posted by Mbirt:

For those who are better with the German language: in their comparison which shows the 360 degree firing order to make more power than the 180/540 degree firing order, did they expand the intake plenum (intercooler tank) volume to compensate for the uneven firing order? I would not have expected the difference in power to be that great, but trying to minimize intake plenum volume would do that.

In the whole document there is no word about the intake plenum. I don't know what the original intent of the document was, so I don't want to judge, but it doesn't go very deep and a lot of assumptions aren't explained at all.
But I wouldn't tell everything in public either .

Hey Guys,
would anyone care to forward me the pdf as well?

quote:

Originally posted by TMichaels:
Hey Guys,
would anyone care to forward me the pdf as well?

+1