Thats what im looking at... Stealth install and removal for those nasty trip to the dealers.... =)

 

Shiv,
I have a question for you regarding this thread:

https://www.evolutionm.net/forums/sh...threadid=24551

Looking at the Dyno charts from Altered Atmosphere, why is Dyno #6 and #9 different so much? Both cars equipped with Vishnu DP, Hi-Flow Cat, Cat-Back, and XEDE. But why a 15whp difference? Is there something else different about both cars that were not mentioned? Maybe you can clarify on that. Thanks!

shobe

 

me too

 

i agree also especially for a no name-ish type exhaust with such a stock like image.it must be solid stainless all the way through .the computer is cemi ok but again for a no name-ish brand it steep.i expect that ecu to be no more than $500.

 

The XEDE tuning and exhaust modifications couldn't make up for lost hp from somewhere else. My car (#9) dynoed around the same difference from #6 when both vehicles were in stock form on the exact same day and same dyno as well. That hp could be lost from anything such as slightly different piston tolerances, etc. That same day we had stock Evos dyno between 218whp to 236whp. It seems some engines are built to more exact tolerances.

If enough work is done to both engines, they may equalize at some point, but I have no clue where that difference currently lies.

Mark

 

I'm not sure why you call Vishnu products no-name. They would not be famous in the Honda/Acura market, but Shiv has been around in the Miata and Subaru world for years and he's a very well known engine management tuner.

Also, you can check out various dyno runs of Evos on 93 octane at the link below:
https://www.evolutionm.net/forums/sh...threadid=24551

Mark

 

I'm very impressed with the in-depth discussion on this ECU topic. Thanks Shiv and other people for these valuable info.

I have some questions about the Vishnu Stage Zero upgrade, much big will it impact the emission? That is, will it passes the nasty California emission test if I install that? Also I have a concern about the gas mileage, will that drop the gas mileage noticeably? I definitely won't want to get the mod that turns my Evo a gas monster...

Lastly, can someone post a audio clip of your stage zero exhaust?

Thanks!

 

I believe that mod is called the throttle.

In all seriousness, I think I am seeing slightly better gas mileage with Vishnu S0, perhaps owing to the leaning out of the A/F ratio in the higher RPM's? Anyone else with Vishnu S0 noticing this or am I nuts?

 

Hi guys,

The Stage Zero should have no negative impact on tailpipe emissions. We've done NOx, CO and O2 readings (at idle and at 3000rpm) with the Stage Zero installed on our shop car and they were virtually identical to the results when the car was stock. Just one of the steps in the long and arduous CARB exemption process.

As for fuel economy, it should improve noticeably with the Stage Zero installed as both fuel and spark curves are mapped to improve operating efficiency over the entire rev range at anything greater than 1 or 2 psi of boost. Fuel economy at vacuum cruise should remain largely unchanged. But who's at cruise all the time?

Cheers,
shiv

 

Shiv, I need to clarify something. There will be "one size fits all" ECU maps that don't require any dyno tuning and will be perfectly safe to run on all cars with a specific set of modifications?

Jesse

 

You shouldn't have any problems with emissions. This thread has a sound clip of the Vishnu dp, hi-flow cat, and cat-back exhaust:
https://www.evolutionm.net/forums/sh...threadid=24352

Mark

 

Sort of. I currently have safe and sound XEDE maps for stock EVOs, EVOs with a cat-back and EVOs with cat-backs and downpipe. For both 91 and 93 octane. So basically six maps for different conditions. Tell me what you got and I'll give you an appopriate map. No need for further dyno tuning or fiddling.

One reason I'm traveling all around the US (CA, DC, Washington State, NYC, etc) for EVO tuning is to constantly refine and test new maps in different cars in different environments on different dynos.

Cheers,
shiv

 

Wow. No emission impact, better performance and yet better gas mileage? That's the first time I heard of a performance modification that actually improves the fuel efficiency. I think you should convince to put your product on as a factory option like the FQ300 selling in UK!!

 

Shiv,

Since you tuned my XEDE, I have decided to remove the dp and hi-flo cat retaining only the cat-back for Auto-X classification purposes.

What impact will this have other than no longer being an optimized map? Any thing gonna grenade on me?

Also you told me to remind you about getting the knock sensor feature added to my firmware. What do I need to do?

Thanks,

 

Hi John,
There is nothing inherently dangerous about still running your current XEDE map after the downpipe removal. XEDE map database will also be on-line (on our website) next week with updated versions of Xupdate and XMap and a basic feature tuning guide. You might want to try a couple of different maps yourself to see which one works best for you.

As for the knock sensor feature, it's already in your XEDE. No need to update your firmware. Wiring directions and basic info will be in the upcoming documentation. The new firmware upgrade I told you about last week (and am testing right now in our EVO) introduces closed loop boost control, real-time map switching and a few other neat features.

Cheers,
shiv