https://www.evolutionm.net/forums/ev...-lbs-gain.html

Intake, catback, tune Evo X. 340whp, 364wtq.

I might have to put the talon aside and autocross the X.

 

I'd write a letter that ECU vs boost controller only benefits certain turbo cars and not others then, whereas both will benefit all classes of turbo cars?

 

That's a good point, but it's also worth pointing out that opening up boost control hardware changes is more in line with how enthusiasts typically modify their cars before reading the SCCA rulebook. One of the goals of the ST classes is to allow common modifications for street cars, and boost control is one of the most common modifications for boosted car enthusiasts.

 

You guys can try, but there's an extreme aversion to opening up boost in ST*. I think the ship has sailed on "common modifications", it would have had to have been instituted a long time ago.


In my opinion it's more likely that they will issue a tuning take-back and revert to stock ECUs only than to allow modifying the boost control system.

 

I also don't think they will go that path of opening more things up. That list is long and soon things would get to the SP level, where things are not that great as of last few years/decades.

And, taking toys/mods away from folks in ST would probably hurt the category more it would be beneficial - I just don't see revering anything back to anything...

 

Opening up boost control does not get anywhere near SP level. Stock injectors are still a huge limiting factor since you can't run E85 and all the boost.

 

It doesn't get to the SP level, but it is going in the same direction.

Since one of the major reason for bringing open ECU to the ST is inability to police such a common mod for turbo cars and mechanical parts of the turbo control are easy to verify for legality, I really don't see this being extended to include it.

The only reason for including such a mod is to give more power for some/all of the turbo cars, which is not intent for allowing open ECU in ST. Extra power that some/most turbo cars will get from this is a necessary evil that seem to be less of an evil compare to the inability to verify legality of the ECU code changes.

At least, that is what I think SEB is doing this for...

 

A new allowance for boost control changes only makes sense if the current proposal passes. Because if the proposal does pass, SOME cars will have unrestricted (except by physics) boost.

My grenade proposal for ST* would be to open up the ECU but take back all the exhaust modifications (i.e. stock or stock-like cats and you can't remove any). I suspect someday it will be a lot harder to pass inspection with an ST* car than it is today.

 

Figure I would update this thread with my findings on my EVOX set up.


Modifications:
FA500 Coilovers (custom valving, custom spring rates 12k Front 16k Rear
Ciro Front brackets on full stiff
18x10.5 ET22 Wheels
275 Rival S tires (not stu legal, will be used to kill off at locals before 265 are bought)
Cobb SF Intake and Inlet
AMS High Flow Pipe
3 inch Catback
AEM Boost and Wideband
Open Source Tune for the proposed open boost tune. I will be making a 2017 legal tune within a week for comparison.


Virtual Dyno result with open boost:



Wheels and Clearance:




Front Clearance: Camber is at -1.5, alignment will be set to 3.7ish. I do not anticipate any rubbing or issues.




Rear Clearance: Camber is at -1.2, alignment will be set to -1.8ish. Rear will def need to be rolled.




Oddly during a quick test run, no rubbing during normal driving. Clearly it will rub during high loads.


Anyway the car is coming along nicely. I will update once I get the roll/alignment to show exactly what needs to be done. Keep in mind I am on wider 275s in these pics.


I will also show a direct comparison of stock boost table vs open boost tuning.

 

Don't get your hopes up, that tune is def not using the legal stock boost control system. Holding that much boost at high rpm on the stock solenoids is impossible. They are either using a 3 port or boost pills.....not legal.

 

The green line is about the max of stock solenoids with the stock O2 housing, downpipe and cat, with a 3" cat back and intake. I know this because that's exactly what my GF's MR does with WGDC at 100% on the stock solenoids...lol. The red and blue lines seem like they're probably a boost controller. Adding a test pipe and O2 eliminator DP with a dump won't make that much more boost, especially up top, with the stock solenoids.

 

My boost trace above is with maxed solenoids. You are simply not getting any more boost unless you somehow restrict the exhaust wg flow or mess with other hardware. 24psi spike down to 16ish by redline.

 

An O2 dump will make more boost due to reduced back pressure at the turbine outlet.


Does your car have a high flow cat, or a test pipe?

 

o2 dumps are not legal. The car has a AMS High Flow Cat pipe on it.

 

Perfectly legal:


Exhaust manifolds, headers, downpipes, and associated EGR tubes may be replaced with alternate units. Exhaust exit may be relocated provided it meets Section 3.3.3.B.16. Relocation of the oxygen sensor on the header is permitted. Exhaust heat shields which cover only, and attach solely to, these parts may also be replaced, removed, or modified. All other exhaust heat shields may be modified the minimum amount necessary to accommodate allowed alternate exhaust components. Mounting brackets/hardware which serve no other purpose are considered part of the exhaust components.


3.3.3.b.16 says exhaust must exit behind the driver or the side of the car. Well, a wastegate dump isn't technically the exhaust, and every other racing organization makes exceptions for external wastegate dump locations. And I've asked my local about O2 dumps and have been told they're fine.