Legality of crank swaps

[JS154]

The M3 3.0 bmw in a light weight chassis would still have to weigh 3300 lbs. The 3 rotor isn't allowed in STU.

...and has to use stock cams. That will never be a competitive engine in STU with that restriction/requirement.

[Greg Amy]

...and has to use stock cams.

How do you figure? There is no build restriction placed on any 3.0L BMW engine in STU. The E36 M3 3.2L engine has to run stock cam lift (not stock cams) this year because the class displacement limit is currently 3L; however, that engine will be allowed to run uncorked next year (@3520# pounds) when we raise the displacement limit to 3.2 liters for 2012...

I believe our plan is to leave that current engine build restriction in Table A for 2012 to accommodate a Spec E36 classing request, so you can build it either way, whichever you prefer. - GA

[Z3_GoCar]

Then what about the S-54 3.2l motor that's currently classed in STO?
Will it be legal for STU at that point? You let the S-52 with it's crappy stock intake manifold in and by opening it up to all 3.2l motors you'll get the S-54 with it's individual throttle body intake manifold and ability to rev to 9k rpm.

[Greg Amy]

Then what about the S-54 3.2l motor that's currently classed in STO? Will it be legal for STU at that point?

All 3.2L engines will be allowed in STU in 2012. This car will then be dual-classed in STU and STO, different prep levels, different weights.

You let the S-52 with it's crappy stock intake manifold in and by opening it up to all 3.2l motors you'll get the S-54 with it's individual throttle body intake manifold and ability to rev to 9k rpm.

Warts and all. We can't promise everyone will be competitive, and the class gives you flexibility to find your preferred combo.

If this engine over-performs to our class targets, it will either get excluded from STU (see: ITR and S2000 engines in STL) or it will get weight. - GA

On edit: if you think the engine will over-perform relative to all other choices, then please do send in a request to exclude the engine, with appropriate supporting information. That info should include supporting data on what the output capability of the engine can be within the STU regs (or reasonably close) and why you believe that's more than the existing cars in the class.

[JS154]

Then what about the S-54 3.2l motor that's currently classed in STO?
Will it be legal for STU at that point? You let the S-52 with it's crappy stock intake manifold in and by opening it up to all 3.2l motors you'll get the S-54 with it's individual throttle body intake manifold and ability to rev to 9k rpm.

Software tuining only on the S54 is shown below. 100 octane race gas is well-settled to allow 8more hp on the S54 engine as well. And that's just a tune and gas. No headers, compression or cam bumps, nothing.

The S54 engine has no business being in STU.

[Greg Amy]

The S54 engine has no business being in STU.

300 whp is NOTHING in STU. With a weight of ~3500# a 3.2L engine can put out somewhere around 385 crank and still be within the class goals (a guesstimate; I don't have the exact numbers).

You guys need to realize that STU ain't no "let's just cobble something together and go racing" kind of class. STU is a "let's compete in World Challenge GTS-caliber cars". If you're not happy competing against a RealTime Racing-quality Acura TSX, or a Stasis-quality Audi A4 turbo AWD, or a BimmerWorld-quality BMW E46 M3, then you are going to be very frustrated and very unhappy in STU.

I'm not trying to be an ass. We most assuredly welcome your participation in STU, but you need to "level-set" your expectations with that mindset.

GA

[Z3_GoCar]

300 whp is NOTHING in STU. With a weight of ~3500# a 3.2L engine can put out somewhere around 385 crank and still be within the class goals (a guesstimate; I don't have the exact numbers).

You guys need to realize that STU ain't no "let's just cobble something together and go racing" kind of class. STU is a "let's compete in World Challenge GTS-caliber cars". If you're not happy competing against a RealTime Racing-quality Acura TSX, or a Stasis-quality Audi A4 turbo AWD, or a BimmerWorld-quality BMW E46 M3, then you are going to be very frustrated and very unhappy in STU.

I'm not trying to be an ass. We most assuredly welcome your participation in STU, but you need to "level-set" your expectations with that mindset.

GA

Ha, that's only 15/20 hp more than the oe CSL, it's still got at least another half point of compression, intake/exhaust port jobs, removing the remaining cat's and mufflers, and the intake work left to make more than that.

You should have access to the World Challenge VTS horsepower results. The VTS I have doesn't list the hp:

http://www.world-challenge.com/inclu...dc1f09a88ab97c

[Z3_GoCar]

Ha, that's only 15/20 hp more than the oe CSL, it's still got at least another half point of compression, intake/exhaust port jobs, removing the remaining cat's and mufflers, and the intake work left to make more than that.

You should have access to the World Challenge VTS horsepower results. The VTS I have doesn't list the hp:

http://www.world-challenge.com/inclu...dc1f09a88ab97c

Chuck Stickley's already got 400hp from his S-54:

http://forums.bimmerforums.com/forum...t=stickley+s54

[JS154]

How do you figure? There is no build restriction placed on any 3.0L BMW engine in STU. The E36 M3 3.2L engine has to run stock cam lift (not stock cams) this year because the class displacement limit is currently 3L; however, that engine will be allowed to run uncorked next year (@3520# pounds) when we raise the displacement limit to 3.2 liters for 2012...

I believe our plan is to leave that current engine build restriction in Table A for 2012 to accommodate a Spec E36 classing request, so you can build it either way, whichever you prefer. - GA

Correct on wording regarding stock camshaft LIFT.

BMW E36 M3 (95-99) max displ 3200 min weight 3200
Engines are permitted 0.040 overbore, 0.5
point increase in compression.
Engines must use the OEM camshaft lift.

'95 was the 3.0L
'96-99 was the 3.2l


With that table, is there anything stopping someone from dropping a 3.2L S54 into an E36 M3 right now, overboring and bumping compression 0.5?

The only limit is on max displacement it seems, for the E36M3, which is a chassis. Nothing stopping anyone from putting a built S50 (3.0L USDM engine) into an E30 bmw and going nutzo with cams and upping compression and such...that will be 290 at the wheels easy in that case.

If this isn't class creeep I don't know what is. If that's the intent, so be it, but it would be wise then to also do something along the lines like make STL a National class and bump the displacment limit to under 2500cc, to give all the current STU cars. Or perhaps just leave the class alone for a little while. Rules stability is important, lack of rules stability was a huge problem for BMW CR for a number of years and the result was significantly declining participation from 2002-2007.

Increasing the class displacement limit to 3.2L is solving what problem that presently exists? That opens the door to the E46 M3 with the S54 engine and the Acura NSX with the C32B engine, just off the top of my head.

[JS154]

I believe our plan is to leave that current engine build restriction in Table A for 2012 to accommodate a Spec E36 classing request, so you can build it either way, whichever you prefer. - GA

SpecE36 (BMW CR) already fits in STU, stock 2.5-2.8L engines, stock brakes and transmissions at just under 2700# IIRC. A great car for ITR, and a field filler for STU even at it's present weight. with the 1.1 ratio it will become a backmarker in STU.

Well prepped and well driven they turn high 2:13's low 2:14's at the Glen, which is 5-6 seconds/lap off this years STU leaders.

[Greg Amy]

...is there anything stopping someone from dropping a 3.2L S54 into an E36 M3 right now, overboring and bumping compression 0.5?

Yes, the class does not currently allow 3.2L engines, except as per that table. And, as per the opening philosophy, you cannot take an engine from that table and install it into any other chassis.

However, the class displacement limit will be bumped to 3.2 in 2012 (assuming BoD approval, which I wholly expect) so it will be legal for next year. And if someone does it, jesu kristy I'd love to watch that!

Nothing stopping anyone from putting a built S50 (3.0L USDM engine) into an E30 bmw and going nutzo with cams and upping compression and such...that will be 290 at the wheels easy in that case.

Correct. See above "jesu kristy".

If this isn't class creeep I don't know what is.

It isn't creep. It's the exact philosophy and intent of the class, the kind of thinking and engineering we're encouraging for STU.

This is STU. See post above.

...it would be wise then to also do something along the lines like make STL a National class...

Ah, a man with own heart. Help promote it, send emails to your reps, encourage people to double-dip in STL to get its numbers up.

... and bump the displacment limit to under 2500cc...

Nope, sorry. STL was created for two basic purposes: one, because there was no way to get sub-2L car light enough to make them competitive in STU; and two, to have a lesser prep version a la the current World Challenge Touring.

If it's your contention that 2L-2.5L cars are in the same boat as STL, where they can't get light enough or be allowed enough mods to compete with 3.2L full-tilt-boogie cars, then that's another matter entirely. The resolution for that may be another class, though given STL's difficulties with getting National status I'd not hold out hope for that. But if you can demonstrate that a full-tilt-boogie (ftB) 2.5L car cannot EVER put out as much power-per-cc as a ftB 3.2L car, no matter how much money is tossed at it, then you'd have a leg to stand on. But I've not seen anyone try, so it's hard to gage.

Or perhaps just leave the class alone for a little while.

That's where we are now. We spent a lot of time on the class this year trying to figure in how we were going to merge in WC cars, and how to handle forced induction, and to get a general philosophy hashed out and published so that we have a strong foundation for going forward. I'd like to think we're there (if you think differently, speak up; we're listening). There are NO (none, zip, zero, nada) major changes in the works for STx, the only thing we expect to see going forward are classification and allowance requests.

Increasing the class displacement limit to 3.2L is solving what problem that presently exists?

To discontinue the consistent requests for 3.2L cars as specific allowances, cars that we think fit within the performance goals of the class. The S54 fits within that expectation and is weighted at the same 1.1#/cc as all the other cars.

SpecE36 (BMW CR)...a field filler for STU

I concur. Do not read in those allowances as expectations of competitiveness. They are, for the most part, responses to specific requests for inclusion. "Sure, come play in the pool, but don't expect to win." Same goes for IT cars, Spec Miatas, TDI Cup cars, etc.

GA