[sstarch1]

BMW E90/E92 335i Engine Modification FAQ
Created November 23, 2006
Author: sstarch1

Vishnu Tuning

References

XEDE for Sale!

Most "official" support thread from Calvin and Hobbes(?) from Vishnu

XEDE Numbers so far...


Take 1: 335i Tuning from the Vishnu Nerds.
Take 2: From Vishnu – Tuning the 335i
Take 3: Vishnu 335i coupe tuning update
Take 4: Vishnu 335i: Tested the new Dealership ECU update on the dyno
Take 5: Vishnu 335i – Finally tested the Vishnu Stg. 1 “kit”
Some Engine Tidbits from the Vishnu nerds.
Vishnu’s first customer for XEDE+Exhaust
Take 6: Vishnu does Canada
Take 7: We finally dyno a Steptronic all proper-like
First production Vishnu " PROcede " installed! -- Results


Q's and A's

GENERAL
Q: Is the Xede a small chip card placed in a free slot inside the ECU panel?
A: Not quite. It's a separate computer box about 1/4 the size of the factory ECU. It sits just next to the factory ECU in an empty "shelf". Very convenient

Q: If the dealer reprograms your ECU, will the settings remain the same with the thought of having to remove the Xede before reprogramming?
A: Yes, the ECU can be reprogrammed independantly of the XEDE. The two are fully discrete from each other. Likewise, you program the XEDE without programming the ECU.

Q: Is the installation simple with no wiring, cutting, etc required and take less then 15 minutes?
A:Correct

Q: Will the Xede cost $3000 being released mid January?
A: Not quite. The current (EDIT: ADDED 11/24/06) intro price for the XEDE kit (XEDE, boost controller and harness) is $1300. It may increase slightly in January.

Q: Does it improves gas mileage under normal conditions 1-2 and loss of 3-4 under heavy?
A: Yes.

Q: If the Xede is a card (like a video card in a pci-e slot on a computer) couldn't the dealership find it when lets say they look in the ECU panel?
A: As mentioned the Xede is its own box with a wiring harness and a serial connector (for laptop interface/tuning) coming out of it.

Q: What is piggy back riding the ECU?
A: Piggy-back computers, be definition, work with the factory ECU, not instead of it. The XEDE essentially recalibrates all the sensors to induce a higher level of performance without the ECU being the wiser.

Q: Will you offer your products to us in europe also? Can we get a plug and play Xede?
A: I'd be happy to ship overseas. But without confirming that the european cars have the same ECU code/functionality as the ones in North America, I wouldn't want to risk it. I have received a couple of emails lately from folks in europe asking me to come out there to install and tune Xedes. I'd certainly be up for it if there is sufficient demand.

Q: Will future maps be free?
A: Yes, maps are always free with XEDE.

Q: Is the XEDE 100% undetectable by the dealership?
A: Yes, as long as the XEDE with all components are removed carefully and completely. The dealership can though notice a great change if they driver the car with the XEDE in play.

Q: How much is custom tuning and when will it be available to me?
A: Vishnu travels to major cities at least 2 times a year with custom tuning being $250 hour plus dyno renting.

Q: Will XEDE work with steptronic and paddle shifted 335i’s?
A:Yes

Q: What are these “maps”?
A: Maps are a given number of offsets loaded into the XEDE and tells it what to do and what the car to do.

Q: Where is this “switch” to switch maps?
A: The switch is part of the XEDE harness & we are working on a indoor cabin switch as well.

Q: Can the XEDE be connected to the sport button allowing it to be turned on and off?
A: There probably is, but we have not explored that as we want to make sure that the XEDE is not intrusive to the car.

Q: Where is the XEDE harness connected to?
A: ECU

Q: Is there anyway to get the XEDE tuned before it leaves the factory on order?
A: Because every car is different, having an aggressive map at start would not be ideal.

Q: How do I update the map from my computer?
A: The XEDE works with a serial port cable. One can buy a serial cable to USB cable to link to more updated computers that don’t have serial ports. The maps will be on our site as a open source and free for anyone to download.

Q: Has the rev-limiter and speed limiter increased or removed?
A: No


PERFORMANCE

Q: Is the XEDE tuning have dynamic power mapping?
A: All modern cars have what you may call "dynamic mapping," in the sense that they all search for targets, and make changes to the map if these targets are not met. Now, altering those targets without being over aggressive is the tricky part (the part that hasn't been figured out by audi tuners). So, this brings us to your question about the xede being static. The base Xede is static. Using 3 dimensional maps, it outputs a given value per a given X and Y value. (Load or variable being Y, and RPM being X) With that said, the Xede is working in conjunction with your factory ECU which is not static (this is the brilliance of an intercepter system). The factory ECU still has all of its ability to step in and make changes when it sees fit. So, the Xede is static, but it does not work in the static manner that a standalone does.

Q: What is the MPG while using the XEDE?
A: During normal driving, expect 1-2mpg improvement. If you're flogging the car hard, expect to get 3-4mpg less.

Q: What is the confirmed zero to 60 times?
A: In the low 4s range. Depends on surface quality and launch.

Q: What is the confirmed qtr mile times?
A: To official times yet. I'd expect mid to high 12s. Time will tell.

Q: How useful is all this power if you don't have an LSD?
A: Very useful. See videos

Q: What is the practical HP gains without the custom exhaust-I'm not that interested in PEAK HP, more middle of the range HP...
A: On 94 octane, we've seen gains of 55-60whp and 70-80lbft of torque. At just 10-11psi. With no mods other than the Xede.

Q: What additional boost with the XEDE create w/out the custom exhaust?
A: Boost pressure are 10-11psi with the factory exhaust. 11-12psi with the upgraded exhaust.

Q: Does it have 0-60 in low 4s based on conditions and 1/4 undertermined but expected mid-high 12's?
A: Yes and Yes.

Q: What are the octane variations available?
A: 91,93,94, 100+

Q: Will the XEDE be self adaptable to future aftermarket upgrades such as exhausts, etc?
A: No, but one should load a new map to maximize the potential power when available or ship the XEDE back to us for this configuration.

Q: What happens if I order a 94 octane XEDE and fill up with 91?
A: Take it easy with the car until one can burn off the tank or turn the XEDE back to stock.

Q: What is the difference between ordering the XEDE and getting it custom tuned?
A: Not all cars are the same and with that we are able to make more power with a few slight tweaks.

Q: Will I get any gains if I have a 91 octane XEDE and put race fuel in my car or anything higher?
A: Although it won’t negatively affect the car in any way, one can’t take full advantage of the gas without the proper map loaded.

Q: What are the expected numbers for 91 octane with just the XEDE?
A: 320whp & 350rtq.

Q: I am very interested on installing a BOV such as the upcoming one from CP-E, any problems?
A: It is best for one to resist the temptation of the BOV as our cars were not designed to release excess boost pressure into the atmosphere. Doing so will effect your tuning and cause the car to run poorly. The car was designed to recalculate that excess air back into the intake system, bleeding off the air that was accounted for by the MAF sensor will confuse everything.

Q: What happens if I have a 91 octane XEDE and my gas station doesn’t have “true” 91 octane fuel?
A: Slight variances on octane will be fine true or not.

WARRANTY/SAFETY

Q:If the dealership doesn't detect XEDE will the ECU somehow detect it?
A: No. The Xede is completely invisible to the ECU and dealership.

Q: How long will Vishnu provide support for the product?
A: We still support products from 1999 (the first year of our company). So I don't think this is an area of concern.

Q:What is the risk in using mods that will be detrimental to the reliability of the car?
A: Shiv@Vishnu

Q:Since BMW tuned the engine for 8.5 lbs of boost, and the direct injectors are rated for 3000psi, isn't the additional boost from XEDE tuning going to "stress out" the injectors? Are there any long term tests out there to show that the XEDE system doesn't hurt the injectors?
A: I'm not sure how you can stress out a solenoid other than subjecting it to too high of fuel pressure or running it static/wide open too often. But for what it's worth, we don't run any higher fuel pressures that stock with the XEDE. Nor do we run the injectors static.

Q: Will constant installing and uninstalling of the XEDE cause problems, etc?
A: No, as long as it is safely and completely removed.

VF Engineering
VF Engineering working on upgrades for the 335i

HS-Elektronik
HS 335i Chip tuning (Europe)
http://www.hs-elektronik.com/datenbl...35i-306ps.html

Miscellaneous

E92 335i CP-E TiAl BOV Kit Prototype
335i BOV Valve Installed
Stock 335i/Vishnu 335i/E?? M3 Dyno Grpah Comarison
Milltek HyperBoost diverter valve / BOV and exhaust
BMP Design catback exhaust systems



Work in Progress:

What sort of actually questions are worth answering specifically?
Post the questions and answers and if they sounds good, ill add them to the specific section. Or you could post the questions only, and hopefully we can all muster the energy to asnwer them.


Feel free to PM me with any request/comments/tips.
..i think this faq is about 10% done..

[sstarch1]

Added, take 6.
Any suggestions or additions by the way?
Just let me know.

[OpenFlash]

Wow. Great work sstarch1. Thanks for taking the time to do this I'll throw in my 2 bits...

1. Is the XEDE tuning have dynamic power mapping?
Answer: ????????

I second that


2. What is the MPG while using the XEDE?
Answer: During normal driving, expect 1-2mpg improvement. If you're flogging the car hard, expect to get 3-4mpg less.

3. What is the confirmed zero to 60 times?
Answer: In the low 4s range. Depends on surface quality and launch.

4. What is the confirmed qtr mile times?
Answer: To official times yet. I'd expect mid to high 12s. Time will tell.

5. If the dealership doesn't detect XEDE will the ECU somehow detect it?
Answer: No. The Xede is completely invisible to the ECU and dealership.

6. How long will Vishnu provide support for the product?
Answer: We still support products from 1999 (the first year of our company). So I don't think this is an area of concern.

7. How useful is all this power if you don't have an LSD?
Answer: Very useful. See videos

8. What is the practical HP gains without the custom exhaust-I'm not that interested in PEAK HP, more middle of the range HP...
Answer: On 94 octane, we've seen gains of 55-60whp and 70-80lbft of torque. At just 10-11psi. With no mods other than the Xede.

9. What additional boost with the XEDE create w/out the custom exhaust?
Answer: Boost pressure are 10-11psi with the factory exhaust. 11-12psi with the upgraded exhaust.

Hope that helps!
-shiv

[Backattack]

1. Is the XEDE tuning have dynamic power mapping?
Let me clarify, will XEDE automatically increase power when using higher octane fuel? I know that there are cars that will automatically tune UP the power when better air, fuel, etc. environmental changes occur.

[sstarch1]

Added more questions from various threads.

Just noticed that the Q/A section is not optimal in that, the questions are presented in no logical order, from a general question to a more complex one. But i might wait to organize that once i have more information to sort, unless it is something that really is necessary atm.

[russ_777]

2. What is the MPG while using the XEDE?
Answer: During normal driving, expect 1-2mpg improvement. If you're flogging the car hard, expect to get 3-4mpg less.

This is ambiguous. The normal driving part is clear. However, it's unclear when you say "expect to get 3-4 mpg less" whether that's referring to the stock car being flogged or the tuned car being driven normally. In other words, if you get 1-2 mpg better than stock when driving "normally", are you saying 3-4 mpg less than that, or 3-4 mpg less than the mileage the stock car gets when flogged.

9. What additional boost with the XEDE create w/out the custom exhaust?
Answer: Boost pressure are 10-11psi with the factory exhaust. 11-12psi with the upgraded exhaust.

This Q/A is also ambiguous. The questions asks what boost is added by the tuning, while the answers state what the absolute values of the boost (presumed max) are with both the XEDE and the XEDE + Exhaust configurations. Two different things. I would prefer to see a set of 3D plots showing boost on z axis, with rpm and throttle % on x & y axes (all other variables held constant) - one for each of the three configurations. That's the only way you'll begin to get a complete picture of what the modifications to boost are.

[Backattack]

New QUESTION!!! Since BMW tuned the engine for 8.5 lbs of boost, and the direct injectors are rated for 3000psi, isn't the additional boost from XEDE tuning going to "stress out" the injectors? Are there any long term tests out there to show that the XEDE system doesn't hurt the injectors?

[OpenFlash]

Originally Posted by Backattack

New QUESTION!!! Since BMW tuned the engine for 8.5 lbs of boost, and the direct injectors are rated for 3000psi, isn't the additional boost from XEDE tuning going to "stress out" the injectors? Are there any long term tests out there to show that the XEDE system doesn't hurt the injectors?

I'm not sure how you can stress out a solenoid other than subjecting it to too high of fuel pressure or running it static/wide open too often. But for what it's worth, we don't run any higher fuel pressures that stock with the XEDE. Nor do we run the injectors static.

-shiv

[eurotekm3]

TECHNIK is also working on single turbo setup for the 335i....

[Backattack]

Originally Posted by shiv@vishnu

I'm not sure how you can stress out a solenoid other than subjecting it to too high of fuel pressure or running it static/wide open too often. But for what it's worth, we don't run any higher fuel pressures that stock with the XEDE. Nor do we run the injectors static.

-shiv

I think the compression ratio on the 335i is 10.5/1, so what exactly is the air pressure in the cylinder at TDC when running stock vs. XEDE boosted? My rough numbers are about 250psi and 275psi respectively. Aren't the D-Injectors working a "little harder" after the XEDE mod? I feel that the Direct Injectors will be the most sensitive part of this equation. Do you offer a warranty on an engine that has been XEDE modded? Or at least warranty the components like the Turbo and Direct Injection system for 50K miles? I mean, if none of this causes any damage to the vehicle wouldn't that be simple to do; provide a warranty? Thanks.... My 335i Sedan will be here middle of December... it will be your next 'experiment' if you can warranty your work and the engine too.

[335i=:)]

Haha. Funny stuff.

Comon guys, warranty a 1st year engine worth thousands. to make a 1300.00 sale? That's rediculous and as a business owner myself am astounded when people ask me similar questions in my own business. At best, he will warranty the xede itself, I would be very surprised if he warrantied anything else. He has alot of overhead outside of the hard cost of the xede itself.

Time to be diplomatic shiv, have fun.

[OpenFlash]

We're thinking of offering a special XEDE that costs $2300. It will warranty the turbos for 4 years. And another XEDE that costs $4300 and it will warranty the engine for 3 years. And if you want the entire turbo/engine warranty, it'll cost $5400. And there will be a 2 page long limited liability clause explaining the things you can and can't do to keep your warranty intact.

Just kidding.

Shiv

[sstarch1]

Hahaha.

[ArmyBimmerDude]

Shiv and Vishnu have been doing all the R&D possible to make sure that the Xede is safe for all 335's out there. He's done tests after tests, finding out what the limits are and pushing the vehicle to them. If there have been errors or problems with the Xede, they have been corrected. And he has never given anyone a reason to doubt him. He's always been straight forward with every question asked here.

So if people are still worried about the Xede damaging their BMW, then maybe its time to either look at the alternatives or to not modify your vehicle.

Me personally, he's answered every relavant question that I've had, and sometimes more than once. I'm getting the Xede whenever it comes out and the exhaust when I get back to the states for 3 months next year.

Shiv and Vishnu rocks

[Backattack]

Originally Posted by Backattack

I think the compression ratio on the 335i is 10.5/1, so what exactly is the air pressure in the cylinder at TDC when running stock vs. XEDE boosted? My rough numbers are about 250psi and 275psi respectively. Aren't the D-Injectors working a "little harder" after the XEDE mod? I feel that the Direct Injectors will be the most sensitive part of this equation. Do you offer a warranty on an engine that has been XEDE modded? Or at least warranty the components like the Turbo and Direct Injection system for 50K miles? I mean, if none of this causes any damage to the vehicle wouldn't that be simple to do; provide a warranty? Thanks.... My 335i Sedan will be here middle of December... it will be your next 'experiment' if you can warranty your work and the engine too.

Making fun of my question is one way of answering it... not sure if it's the right way. It seems the two questions that keep getting dodged are the warranty/factory warranty, and dynamic mapping... I guess it's in your best interest not to answer honestly. Good nuff for me.

[OpenFlash]

Originally Posted by Backattack

Making fun of my question is one way of answering it... not sure if it's the right way. It seems the two questions that keep getting dodged are the warranty/factory warranty, and dynamic mapping... I guess it's in your best interest not to answer honestly. Good nuff for me.

Sorry, I really didn't mean to make fun of you questions. My point is that unless you want to pay a massive premium guarding against something that simply wont happen, the idea of a tuning shop offering a drivetrain warranty on performance items isn't going to happen. I really don't want to charge an obnoxious amount of money for a upgrade kit that delivers 50% of what it should. And the majority of people don't want to pay for such a kit either. Even if it does include a very-limited warranty coverage claim.

And I'm still not sure what you mean by "dynamic mapping." I don't think I have a history of dodging questions (esp. technical ones). So please explain what you mean.

Thanks,
Shiv

[sstarch1]

I think dynamic mapping is the case where, lets say, instead of you loading a XX octane map and a YY octane map, you could have a map that would adjust all the setting to the octane that it reads.

So it would be a more advanced program.

I actually dont know why you wouldnt do that, shiv?
not enough memory or preccessing power? It would be easier, though might take a little longer to develop.
Do you need more data from the different octanes, so that later, you might put out a "master" map that would switch between stock and tune, and read the octane and other pertinents, and then optimize performance.

[RiXst3r]

My buddy with an s4 and a GIAC chip was raving about the "dynamic mapping" and how his car was getting faster and faster as the chip "learned" the engine and fuel limits... is this what everyone means by dynamic mapping?

[Backattack]

Originally Posted by RiXst3r

My buddy with an s4 and a GIAC chip was raving about the "dynamic mapping" and how his car was getting faster and faster as the chip "learned" the engine and fuel limits... is this what everyone means by dynamic mapping?

Please accept my apologies everyone... I am only interested in a lively discussion... I understand that the new BMW inline 6 is really a strong engine and what Shiv is doing is simply tapping that extra engineering for all of our benefit. The next 335 I get will probably be the last car I have for the next 5 years so I want a healthy balance of performance, reliability and flexability. It seems Shiv has really meet those criteria; I'm just a little inquisitive.

Back to adaptive engine control/dynamic mapping...
Yes, a system that can adapt to the fuel, air, air pressure, temperature, etc. And I think that would be a big $$$ project. Now I understand right now for 1300 bucks this system is probably static and that's fine. I'm seriously considering getting it... I will do it, but I want to see you tune it and give me all of the ins and outs about it.

The dealer told me that my 335i Sedan will be here in the middle of December; are you interested? I live in Riverside, CA?

Thanks for entertaining my questions everyone!

[BMWnewbie1]

Vinshu,

You mentioned that stock is build for a specific power/economy/emissions market. This strikes me as being correct. But while we talk about power and economy, where did the emissions go? Dare I say I even care about emissions? Can you tell me what it is going to be like, ballpark?

[Dustin Bramell]

The phenomenon known as "dynamic mapping" in the audi world is not as spectacular as they make it out to be. Trust me, I owned 2 S4s in the past. The "dynamic" part of it is created through over-agressive mapping. The car isn't trying to move up to limit of the ignition advance and fuel tables, but rather being chopped back down to it, through feedback from the knock sensor. This is a very dangerous way of doing things, and normally produces less than stellar results. Case in point, I wrote my S4s off as a tuner car a long time ago.

However, all modern cars have what you may call "dynamic mapping," in the sense that they all search for targets, and make changes to the map if these targets are not met. Now, altering those targets without being over aggressive is the tricky part (the part that hasn't been figured out by audi tuners). So, this brings us to your question about the xede being static. The base Xede is static. Using 3 dimensional maps, it outputs a given value per a given X and Y value. (Load or variable being Y, and RPM being X) With that said, the Xede is working in conjunction with your factory ECU which is not static (this is the brilliance of an intercepter system). The factory ECU still has all of its ability to step in and make changes when it sees fit. So, the Xede is static, but it does not work in the static manner that a standalone does.

Originally Posted by Backattack

Back to adaptive engine control/dynamic mapping...
Yes, a system that can adapt to the fuel, air, air pressure, temperature, etc. And I think that would be a big $$$ project. Now I understand right now for 1300 bucks this system is probably static and that's fine. I'm seriously considering getting it... I will do it, but I want to see you tune it and give me all of the ins and outs about it.

Thanks for entertaining my questions everyone!

[sstarch1]

Added to FAQ. Great Answer.