ST Boost Issue

[chaos4NH]

I think the "tuning" and ECU changes in ST should be a separately discussed issue. Why? Because turbo car boost levels can be manipulated in many ways, some nearly undetectable. For instance, you do not have to go beyond the factory set boost levels - say 16 # in the MS3, but you can extend the RPMs at which the boost is cut. For example, stock boost controller is at 16#, and the ECU sets the RPM of cutting fuel and dumping boost at the waste gate at 5800 RPM, but by a chip change that delays closing of the throttle and extends opening of the waste gate another 750-1000 RPM over stock, a significant change in the peak power level is achieved without changing the boost level. So I will just throw that out for now and intend to address it in detail. ECU changes, chips and "tunes" are too ambiguous, and if allowed, need to be more more clearly defined.
As Will says:
That said, I believe the current non-boost ST rule is probably being stretched a bit, and is mostly keeping the honest people honest.

[nhsilversti]

in my opnion the boost should remain STOCK period. wether it were to be the boost map in the ecu any other means of "changing" boost from where it would have been. no changes should be made ANYWHERE in the boost maps. a car that would normaly be at 12psi @ 6k set to 14.5psi @ 6k (stock peak boost) is what im refering to as ANYWHERE in the boost map.

ted

[chaos4NH]

in my opnion the boost should remain STOCK period. wether it were to be the boost map in the ecu any other means of "changing" boost from where it would have been. no changes should be made ANYWHERE in the boost maps. a car that would normaly be at 12psi @ 6k set to 14.5psi @ 6k (stock peak boost) is what im refering to as ANYWHERE in the boost map.

ted

We are in agreement! Policing will have to be via the individuals conscience.

[cuda6666]

Boost levels can be read and recorded across the rpm range using data logging. Here's how to do it on Subarus:



http://www.legacygt.com/forums/showthre ... ta+logging

Of course, it would be much simpler to just classify turbocharged ST cars up one class from their SS base assuming max boost level HP on the stock turbo.

[WillM]

We are in agreement! Policing will have to be via the individuals conscience.

Me too. I interpret the rule to say that the boost cannot be modified at all, as you guys said above. As with all rules, policing is handled by the competitors of the class via protest.

[rajito]

Of course, it would be much simpler to just classify turbocharged ST cars up one class from their SS base assuming max boost level HP on the stock turbo.

That's an interesting idea.

STI's and Evo's will wind up in STGT against modified Z06 Corvettes, WRX and Speed3's would run in ST1 with ...uh... Buttstangs? Hehehehe!

Another option would be to allow regular mods (exhaust, suspension, etc.) to wind up where they are now. Reprogramming ECU would toss you one level up in ST (assuming all your other changes are ST legal), rather than SP. As I mentioned earlier, most tunes involve raising boost unless the customer requests them to not do so.

Feels like we're creating a lot of rules just to keep the turbos under check

Raj

[chaos4NH]

The like the idea of up one slot instead of going to SP. Don't plan on any ECU changes, so I'd be happy if any that did ended up in ST1. Oh, wait just a minute: In many cases, the ST2 cars were already as fast as the majority of ST1's last year. Joe Lu is certainly an exception!

Raj, we arent creating any new rules by this discussion. I am just throwing out the fact that, without data logging for evidence, we police ourselves. The boost issue certainly puts the Non- turbo cars at a huge disadvantage if ECU mods are allowed.

[eclip5e]

I like the boost level idea how it is currently. It'll be super hard to police otherwise.

If you look at how subaru has changed the mapping of the ECU over the GDA series, it varies alot between model years, and even within model years. One ECU series could have boost taper at 5500 and the next month they release an update where it tapers at 6000. This can be seen with early model WRXes vs later model WRXes.

Changing these properties can allow some evening of the playing field between cars of the same make and model.

I like the rule how it is, but i wont be in ST next year.

[agrabau]

What about drive by wire mapping? that can affect boost and power without touching the boost map.

Maybe ECU mods should be open and power mods via hardware should be banned for ST.? That would be easier to police.

Or.. just say that turbo cars with modified ECUs should be in XX class and not ST.

Just a suggestion since there are a million and one ways to "interpret" the boost rule.

[turtlevette]

When i had my turbo regal back in the 80's the trick was to put a bleed off valve in the pneumatically controlled wastegate circuit. A rubber hose that could be swapped out in a few seconds with a pinhole would do the same thing and be undetectable. The computer would think the boost was lower than it actually was and increase boost. With knock sensing this is a relatively safe practice and the computer continues to maintain the correct air fuel ratio regardless of where the boost is. If you run racing gas, the computer will not sense any knock and will keep the timing advanced allowing some tremendous boost levels. I replaced the converter and mufflers with straight pipe and it still wasn't loud at all. I used to walk big block LS6 chevells and such "like they were standin still" just like the Beach Boy's 409. It was a fun time.

It is so very easy to get huge gains on turbo vehicles with simple tricks such as this. You don't need any high tech mapping, drive by wire, or blah blah blah.

[mossaidis]

When i had my turbo regal back in the 80's the trick was to put a bleed off valve in the pneumatically controlled wastegate circuit. A rubber hose that could be swapped out in a few seconds with a pinhole would do the same thing and be undetectable. The computer would think the boost was lower than it actually was and increase boost. With knock sensing this is a relatively safe practice and the computer continues to maintain the correct air fuel ratio regardless of where the boost is. If you run racing gas, the computer will not sense any knock and will keep the timing advanced allowing some tremendous boost levels. I replaced the converter and mufflers with straight pipe and it still wasn't loud at all. I used to walk big block LS6 chevells and such "like they were standin still" just like the Beach Boy's 409. It was a fun time.

It is so very easy to get huge gains on turbo vehicles with simple tricks such as this. You don't need any high tech mapping, drive by wire, or blah blah blah.

So... you mean to say no turbo's in ST? YES! I love it! Herb?

[turtlevette]

So... you mean to say no turbo's in ST? YES! I love it! Herb?

NO i don't mean to say anything, just rambling like an idiot.

[chaos4NH]

So... you mean to say no turbo's in ST? YES! I love it! Herb?

NO i don't mean to say anything, just rambling like an idiot.

I think most of the responders got my point, but this talk of changing classes for turbo cars is way off the mark. Despite the large assortment of cars to classify, I think Nate and the others got the basic classes in pretty good shape.
What the issue being addressed is/was the of mods allowed in a given ST class. The rules allow ECU changes, but do not allow boost changes. With few exceptions, ECU mods (chips, plug and plays, piggy backs, etc.) effect the boost profile on turbo cars. Since boost changes are not allowed by the rules (and I agree with it!), I felt that ECU changes for the turbo cars should not be allowed.
As for the boost profile changes that the Subie folks say are constantly being done by the factory, I say tough! EXAMPLE: You should not be allowed to use the 2006 profile on your 2002 year car, as it most likely is effecting boost. You are stuck with the factory settings. Same would apply to my car if the 2008 model has a different ECU package that boosted hp, torque or otherwise changed the boost profile.
So, Ted and I are in agreement, no ECU changes allowed on turbo cars in ST. It just becomes a slippery slope and not enforceable.
Actually Tom, who is rambling now? BTW I thought your tales of early turbo mods were great! Always an education to be gained here on the forum, and it supports my premise very well.
See you all at the banquet.