What's the chassis??

[Z3_GoCar]

Maybe I'm missing something in the STCS, but I'm not sure what "is" a chassis? Is it seperated by vehicle style, sedan/coupe/convertible/roadster? Or would it correspond to GM's x-body/j-body/f-body ect.

Why ask this question: well what if a chassis was built from 1992 to 2002 but one varient of that chassis (say a sedan built from 1996-1998) had access to say a throttle body. Would all the other varients (say a coupe built in 2000) have access to that throttle body?

 

[Z3_GoCar]

No one has any idea??

Alright, so how do I get this clarified? Other than a letter to the CRB, are there any other ways?

 

[Greg Amy]

Maybe I'm missing something in the STCS, but I'm not sure what "is" a chassis? Is it seperated by vehicle style, sedan/coupe/convertible/roadster? Or would it correspond to GM's x-body/j-body/f-body ect.

Don't overthink it, don't overanalyze it. It's a BMW Z3, or an Acura Integra, or a VW Golf. If you want to get technical, the chassis is the part that all the drivetrain and suspension bits attach to.

...if a chassis was built from 1992 to 2002 but one varient of that chassis (say a sedan built from 1996-1998) had access to say a throttle body. Would all the other varients (say a coupe built in 2000) have access to that throttle body?

Yes, if you swap in the entire engine and intake that this throttle body was attached to. But if you're asking if you can take a throttle body from "this" engine, attach it to an intake manifold from "that" engine, bolt it to the head from "another" engine, and bolt that to a block from "that other" engine, then install it all in "that" car, then the answer is no. Frankensteins are not allowed.

GA

 

[Z3_GoCar]

Don't overthink it, don't overanalyze it. It's a BMW Z3, or an Acura Integra, or a VW Golf. If you want to get technical, the chassis is the part that all the drivetrain and suspension bits attach to.


Yes, if you swap in the entire engine and intake that this throttle body was attached to. But if you're asking if you can take a throttle body from "this" engine, attach it to an intake manifold from "that" engine, bolt it to the head from "another" engine, and bolt that to a block from "that other" engine, then install it all in "that" car, then the answer is no. Frankensteins are not allowed.

GA

Gee Greg... it says "chassis" not "model" that implies that if the four door came with intake manifold A, and the two door coupe or even station wagon didn't, you could mount A on the motors of the coupe or the station wagon as they are the same "chassis". Since ST doesn't have a vin rule then any version of that "chassis" should be able to use any part that was used on the same "chassis". Frankenstein's are already allowed when the intake manifold can be from either the swapped motor or the "chassis", the horse has already left the barn so to speak.

 

[Greg Amy]

You're overthinking it. You should go work for Red Bull. But send in a "clarification request" if you feel the need. We'll change...sorry, "clarify"...the regs accordingly.

GA

P.S. New entries into the world of SCCA wonder why the GCR is 752 pages - and counting - long. This is why. Did you know the GCR was originally something like 42 pages...? No, really.

 

[Z3_GoCar]

Sorry, I understand that the reg's have grown because of questions like mine, and the "over the motor" solo story Josh Sirota re-told a few years ago.

I can say this latest "hair brained" idea came from you though from our little exchange about the Z3 already being spec'ed in STO becuase it's an e-36. But, the only e-36 that came from the factory with the S54 motor was the Z3...

I don't mean to be a pain. I recently had a Belbin team roles test, and my second team role was as a "plant." Combine that with my "perceving" personality, and you get someone who's really primed for ideas. Hey, I think you've got some of this too, what with your take on port-matching Stoke of genius...

 

[jhooten]

STO:
GCR 9.1.4.1.E.1
E. Engine
1 Intake Requirements: All cars shall use the stock or approved air throttling device (e.g., carburetor, throttle body) and intake manifold for the installed engine, unless noted otherwise.


STU:
GCR 9.1.4.2.D.2

1. All cars shall use the installed engine’s stock air throttling device (e.g., throttle body, carburetor) and intake manifold, unless noted otherwise.

 

[Z3_GoCar]

If I'm going to have to make my motor competitive agianst what the turbo guys are putting out, I'm going to have to be "Red Bull" creative, and use everything allowed by the rules. Rotory guys get the periphal port motors, what do N/A piston guys get? I can't use more cam, I can't even use the max cam limit that we have now.

G​

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. Engine​

1. Alternate engines may be used, if the manufacturer of the vehicleand
engine are the same ....

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The chosen engine must retain its original cylinder head and intake
manifold. Competitors must have in their possession a copy of the
factory shop manual for both the drivetrain and chassis for use
by scrutineers. If an engine from a front wheel drive vehicle is
installed in a rear wheel drive vehicle, alternate OEM intake manifolds
may be considered. The long block assembly of the alternate
engine must remain within the engine compartment with no modifications,
however the firewall may be modified to provide clearance
for intake manifolds and/or engine accessories. It is permitted
to use the OEM intake and throttle body for either the chassis or
the installed engine. If needed to allow the intake manifold fit on
the engine, an adapter plate between the engine and manifold is
permitted. This adapter plate must be no more than 1.0 inch thick
and must be made of the same material as either the head or intake​

manifold.

 

[Chip42]

while I agree the assumption of chassis to be limited to the specific year / make / model / body style when that "platform" might be under many models and myriad body styles is a bit fast and loose witht he language, a simple 1 or 2 sentance definition of chasis in the general ST regs can make it all better.

so, if I'm understanding the STCS paradigm correctly, you will be able to swap the throttle body and intake from one body style or chassis to another as part of the alternate engine, but the coupe won't have access to the TB of the sedan or vice versa when a alternate motor never installed in that "chassis" (wide definition) is used.

actually rather clean concept (though I'd argue the value of it) but I agree on the need to make the wording clear lest it get to a level where that decision is made by a third party - i.e. the COA.

 

[Greg Amy]

so, if I'm understanding the STCS paradigm correctly, you will be able to swap the throttle body and intake from one body style or chassis to another as part of the alternate engine, but the coupe won't have access to the TB of the sedan or vice versa when a alternate motor never installed in that "chassis" (wide definition) is used.

I'm not clear what Christian Horn....er, James is trying to get away with, mostly 'cause I don't know jack about the BMWs. But divorce yourself from what engine came in what chassis/make/model; it's irrelevant.

Let's say James wants to install the SX48 engine from the BMW 486i sedan into his BMW Z3. Compliant. He has to take the entire engine assembly from the 486i sedan - including intake manifold/TB - and stuff that into his Z3. He's allowed to use whatever IM/TB came on the SX48. alternatively, he can install the long block from the SX48 and use the IM/TB from his Z3; to make that fit he can create an adapter plate per the regs.

Aside: the intent of that alternate IM/TB allowance was PRIMARILY for FWD/RWD swaps. I suggest we could have done a better job with the wording. The reason for the adapter plate came from a guy wanting to install a K24 into an S2000; the FWD intake would not fit in his car.

In the end, the results of both of these regs are that you can swap in whatever family engine you want and you can use either the donor engine's intake or the donor car's intake. If the desired IM/TB combo came in your car originally, you can use it, regardless of the engine you install. If the desired IM/TB combo came on the engine you're installing in your car, you ca use it instead. But what you CANNOT do is take pieces and parts from different engines and cars and install those on a totally different engine in a totally different car.

Capiche?

GA

 

[Chip42]

I'm not clear what Christian Horn....er, James is trying to get away with, mostly 'cause I don't know jack about the BMWs. But divorce yourself from what engine came in what chassis/make/model; it's irrelevant.

I completely understand what you WANT to allow, but I agree with James that IF chassis X had 2 body styles or varients - say a coupe and a wagon - and the coupe came with a larger TB on what is otherwise the same engine as the wagon, the rules as written might allow him to swap a motor into the wagon (not the factory installed type) and use the TB/intake from the coupe, being as it's the same chassis.

I think "your" definition of chassis is more inline with the IT concept of year (range)/make/model/body style while the general term "chassis" is often synonymous with "platform" and James is exploring that definition (to a non-absurd degree IMHO). define chassis, close potential loophole. btw, it's a stupid rule if he can't have the coupe TB in an othwerwise identical wagon to continue my example. it would deserve a line item allowance at minimum.

 

[Greg Amy]

...IF chassis X had 2 body styles or varients - say a coupe and a wagon - and the coupe came with a larger TB on what is otherwise the same engine as the wagon, the rules as written might allow him to swap a motor into the wagon (not the factory installed type) and use the TB/intake from the coupe, being as it's the same chassis.

The regs do allow that. Explicitly. Unless I'm totally missing what you're trying to say...and in the end, so what?

GA

 

[jhooten]

You do realize, don't you that the STO spec line for the e36/46 is the M3 not the Z3. Use a 3l or smaller and run in STU at 3300#.

 

[Greg Amy]

You do realize, don't you that the STO spec line for the e36/46 is the M3 not the Z3. Use a 3l or smaller and run in STU at 3300#.

We're adding the Z3. Z4 too, probably, and any other BMW you may have an interest in racing in STO against the Vipers, Corvettes, and Porsche 996tt. - GA

 

[Chip42]

The regs do allow that. Explicitly. Unless I'm totally missing what you're trying to say...and in the end, so what?

GA

I think his example is Z3/3XX series car with 2 different motors with 2 sizes of TB. he wants one car, the TB from another, motor from a 3rd. "chassis" as in "platform" is the same between those cars. up until the above comment, I believed your intent was that a Z3 and 3 series were different by rules, so this would NOT be allowed.

"in the end," the STCS places restrictions on component swaps for some sort of regulation ability. I get that even if I disagree with it (should be displacement/cam/compression etc.. and go). but all it means is that certain combos can't play or that 2 otherwise equal engines are held back by chassis choice. I don't see how that's a win for anyone.*

* and I see where a Z3 might be seen as a superior platform to a wagon, and performance balanced accordingly with all else being equal. but that's not the topic here, it's part swaps within a platform that might not be "legal" by some readings of the rules, and a request for clarification.

 

[Greg Amy]

I'm confused, but I just don't know these cars. But, as far as I am concerned, a BMW 345 wagon is the same car as a BMW 345 sedan is the same car as a 345 coupe, so you're free to swap parts all you like between them. The tuning philosophy of Super Touring allows - encourages - that. - GA

On edit: personal commentary, the BMW Z4 really isn't a good platform for this kinda stuff. I remember getting up close to Rob's ITA Z3, and that rear suspension is pretty basic; comes from the E30 chassis, doesn't it? The E36 was a much better rear suspension as I recall, and I'm sure the E46+ is even better...but I'm waiting for Eric to jump in here and clarify this muddiness...

 

[Chip42]

I'm confused, but I just don't know these cars. But, as far as I am concerned, a BMW 345 wagon is the same car as a BMW 345 sedan is the same car as a 345 coupe, so you're free to swap parts all you like between them. The tuning philosophy of Super Touring allows - encourages - that. - GA

On edit: personal commentary, the BMW Z4 really isn't a good platform for this kinda stuff. I remember getting up close to Rob's ITA Z3, and that rear suspension is pretty basic; comes from the E30 chassis, doesn't it? The E36 was a much better rear suspension as I recall, and I'm sure the E46+ is even better...but I'm waiting for Eric to jump in here and clarify this muddiness...

yes Z3 = updated E30 but Z4 I think is E46 gen 1 and E92 gen 2. I'm sure james knows the part in question, I was just trying to clarify what I believed his point was, as I don't think it's very clear either. of course, I'd have never put a VW engine in a 944, so...

 

[Greg Amy]

... of course, I'd have never put a VW engine in a 944, so...

Ugh, that one still sticks in my craw. Not that I disagree with our response - I'm generally ok with VW and Porsche being "same family" - but I see that whole thing in hindsight as us falling prey to someone's cruel prank. We avoided that pitfall with some subsequent letters this year (Toyota engines in Loti, Chevy engines in some British crap, etc) but unless someone shows me a Golf-engined Porsche 944 entered in STU somewhere I'll wear away more of my teeth each time I see that reference... - GA

 

[jhooten]

We're adding the Z3. Z4 too, probably, and any other BMW you may have an interest in racing in STO against the Vipers, Corvettes, and Porsche 996tt. - GA

And hopefully soon this slow POS:

 

[JS154]

I'm confused, but I just don't know these cars. But, as far as I am concerned, a BMW 345 wagon is the same car as a BMW 345 sedan is the same car as a 345 coupe, so you're free to swap parts all you like between them. The tuning philosophy of Super Touring allows - encourages - that. - GA

On edit: personal commentary, the BMW Z4 really isn't a good platform for this kinda stuff. I remember getting up close to Rob's ITA Z3, and that rear suspension is pretty basic; comes from the E30 chassis, doesn't it? The E36 was a much better rear suspension as I recall, and I'm sure the E46+ is even better...but I'm waiting for Eric to jump in here and clarify this muddiness...

E36 and E46 are pretty much the same multilink rear suspension as I understand.
Z3, E30, and E36 Bobtail Ti all use the same semi-trailing arm rear suspension.

remember that:

The rules require that the:

Intake manifold must be from either the installed engine or the chassis. (allowed for motor swaps*)
and
Chassis must be/ have been available through the US dealer network
and
Engines must have been available in North America.

the S54 engine, installed in the E46 M3 Chassis, had ITB's
The S50B30, installed in the Canadian market 1994 E36M3, had ITB's.

So if someone wanted to run ITB's on their 2.5L egine, they could theoretically run an M54 (E46 325 engine) in an E36 M3 chassis.
If the ITB from the S50B30 are to be used it would have to be as a complete engine at 3.0L regardless of which chassis it's installed in.
Since the M54 came in the E46 chassis, the stock ITM would have to be used.

Also note the S54 engine is 3248cc, which is larger then the 3.2L limit of the class.

Note I am NOT saying this IS LEGAL, not am I saying it IS NOT or it SHOULD NOT be legal. I am saying that's how it looks like the rules read to me.