What ...if any.....historical link is there between the Footworks-Arrow F1 Porsche engine ( shown here in one of the responses...as a V-12)...and the CGT V-10 ?????

Architecture / basic design looks awfully similar.........

Wil

Hi Stijn again,

Actually, once you submit a "reply" to the Pelican board, you can click the box that says "notify you when there is a reply". Then you won't have to "surf" and waste time. This is called "E.mail Norification", right about the grey "submit Reply" box. Nice, no?

Since much of my work as an achitect is writing our engineering consultants and Clients with e.mail, I can always "sneak" an extra look into PelicanParts.

eehm , that's why i end up surfing the web a lot
i constantly get drawn to this board by notifications :D

"but boss , i didn't see it was a porsche technical forum, honestly , it looks just like any other IT forum i need for work , honestly"

it does help that i had first pick when we moved our desks around last time.... i'm in the corner , wall to my left, window to my right, nothing behind me that can reflect my monitor, and a nice wall build around me...

Wavey - any idea where that photo of the TAG engine was taken?

BTW: Porsche have been unfairly criticized for the Arrows V12. The engine was designed without knowing what chassis it would end up in - never a good plan ..... :rolleyes: So it really wasn't the engine itself, it was the combination of the engine and chassis, at least according to Manfred Jantke.

Uh -- Yeah. :rolleyes: I was pointing out that the "other" (ie. Non-V6) F1 engine was a V12 as in the picture that I attached.

That's not quite how it worked out. Actually the Footwork engine was the V12 which was (to put it nicely) a dog. http://www.pelicanparts.com/support/smileys/pukey.gif I suspect that it's lack of performance (from an F1 perspective) and all of the money that Footwork had to pay Porsche to develop it most likely contributed to Footwork running out of money. It's not that the engine didn't run reliably -- it did. As I've heard it, the design team was headed up by the same guy who designed the 917's engine. One of the 917's features that was carried over was the center power take-off of the crank. That was all well and good for the endurance racing 917 motor in 1970. But compared to the other F1 engines of the 90's, it was overweight, the CG was too high and it never got around to putting out enough HP. Don't underestimate the impact of engine weight and CG on a contemporary F1 car -- witness performance of the 2003 Renault F1 car with it's wide angle engine which reduced the engine's CG by something like 4 or 5 cm. It was giving up something like 50 HP to the Honda and Ferrari engines, yet the Renault was certainly "The best of the rest" at the end of the season.

So at the end of the day, the Footwork V12 engine was not successful.

The V10 endurance engine is a completely different animal from the V12 engine and I doubt that they carried much over except the DOHC - 4 valve configuration.

John says:

.....The V10 endurance engine is a completely different animal from the V12 engine and I doubt that they carried much over except the DOHC - 4 valve configuration.....

Is this your supposition or can you back this up with data? Not trying anyone's patience ( I hope)...but I would like to see some documented proof either way, since it has been a long standing question that I can't get good answers on...

Porsche has a penchant for not "wasting" a design....they'll use older studies and designs if it avoids having to plow new ground all over again. Case in point...aren't they "both" 68 degree "V"'s ?? I'll "bet" that the CGT is not much more than the F1 V-12 with 2 cylinders chopped off...but I can't find data.

Wil

No, the CGT has power output from the end of the crank

Well, CGT engine is a V-engine and is made by Porsche :-)

Depends what you meen with "carryover". V12 had totally different block, heads, crank and two more cylinders. If that doesn't qualify as "different" then I don't know what does. ;)

They might have reused cylinder head shape (as many do) but I fail to recognize any other similarities except maybe some minor stuff...

In my garage - I wish!

Actually, the source is burried somewhere in my archives. You might try the website on the photo?

Ahhh...Goran....944 and 928 are also very similar from a design / architecture standpoint.....so your argument doesn't hold up well.

I would consider the design "basis" the same if the block casting / reinforcement rib design, cooling passages, combustion chamber design, etc is the same same ( if so). They then can be considered from the same family...especially if the included angle of the "vee" ( are they both 68 degrees??...anybody??) is the same. OK....as you lose two cylinders you can also add/subtract the center power take off. That is an admittedly big difference.

Many other manufacturers use a "modular" design...and these two engines may share more than thought too. I hear a lot of emotional responses, but again...I'm looking for something more substantial which serve to bolster others' "feelings" about this.....

Wil

Wil; You and I agree that Porsche rarely wastes a design idea (in common with most successful technology companies) -- but I doubt that you'll find much connection between the two engine designs. I'm not saying that they didn't copy the oil-pump design, or other details of sub-assemblies. But to scale a 3.5 liter motor up to 5.7 liters...

The F1 engine designed for Footworks.
http://8w.forix.com/por-v12.jpg

The CGT Engine.
http://forums.pelicanparts.com/uploa...1104954808.jpg
http://www.germancarfans.com/photos/...02/1062big.jpg

Some key comparisions:
V angle: F1 - 80 degrees versus 68 degrees in the CGT
Bore x Stroke: F1 - unknown, but competitive engines were about 3.46 x 1.89, CGT: 3.86 X 2.99
Cylinder Spacing: Unknown
Valve angle: unknown

BTW; The Porsche Footwork V12 FA12 weighed about 396 pounds and was reported to put out something like 700 HP versus 340 lbs and 770 HP for a Honda RA122E/B V12.

In general, Porsche has never talked about the V12 F1 engine and so details have been almost non-existant.

Here's a thread from another BBS that discusses it some detail with the interestesting reference to another source about half way down.

That clutch really is a work of art... allbeit very expensive art!

John:
Thanks for posting....some meaningful insight was gained...these don't look like up/downscale of similar architecture afterall....

Wil

What's interesting to us motorcyucle riders is that Porsche has "discovered" the multi-plate clutch (thus allowing it to be smaller), and the "cassette" transmission, which is also a motorcycle-style gearbox.

Is this the wave of the future? I wonder why Honda is not doing this in their cars, since they are the masters of compactness in motorcycles.

No discovery there. Multi-plage clutches have been very common in racing cars for decades -- at least since the '70's. The reason why they have not been generally used on street cars appears to be...

1) No Clear Benefit - No great benefit since for street use a fairly substantial flywheel is a benefit since it smoothens out the idle and makes the car easier to start from a dead stop. Basically most cars have full sized flywheels, so why bother making a small diameter clutch.

2) Action - A multi-plate clutch has a substantially different feel, similar to how re-arranging the clutch disks changes the feel of a limited slip diff. Basically a mult-plate disk will have sharper (less gradual) take-up. To the driver the clutch will be either off or on, with very little in between. This can be a difficult thing for many drivers to manage in stop-and-go traffic.

3) Service life - With a standard clutch there is two large contact surfaces, so any wear is spread over a large area. So if you wear 5 thou off of each surface, you've worn 10 thou off the assembly. Furthermore the wear is relatively low since it is spread out over a larger suface. In a multi-plate disk there are multiple small contact surfaces stacked up. Each disk will wear faster for a given amount of slip because of the smaller surface area. If you have a 3 plate disk (6 surfaces), and each surface wears by the same 5 thou, your assembly has worn by 30 thou and managing the tolerances starts to get difficult. I believe that recent developments in clutch disk materials technology has improved this situation over 10 years ago.

As far as a cassette gear cluster -- I can appreciate the benefits of this in a race car where frequent ratio changes are needed and the packaging is tight around the ground effects defusers, but why bother for a street car? Have you looked at the area around most gear boxes -- not generally the most tightly packaged area in a street car -- especially in FWD cars. So what's the benefit compared to the incremental costs?

Hi John,

Couldn't have said it better myself.

Look at the diagram of the Carerra GT a few posts back, and you'll see why I still think this might be the wave of the future for "sports cars" not
"street cars".

Isn't this fun?

What do you guys think this thing is worth? Damn, it would look good in my garage. :)

Here's a photo I came across of the Footwork V12;

http://forums.pelicanparts.com/uploa...1106521583.jpg

I have that poster in my room :)

Zach - the German website I found that on said it was "very rare". I think they were selling them for 190 euros!