[DrDomer]

As an upcoming Procede user, I was hoping to start an intelligent discussion about people's expectations of reliability of 335's with the Procede or Turbo Tuner or other ECU modification. I was hoping to base this discussion on people's experiences with tuning other turbo vehicles, as obviously we haven't had a lot of time to know how things will go with the 335.

I know.. I know.. the whole pay to play argument. I have no problem with that.

I would also prefer it if people (hopefully with experience and knowledge) would weigh in on exactly how these control units modifications of engine working parameters would possibly affect short and long term reliability.

I have seen an inkling of this in other threads. Shiv has made some references to "safety" when designing the Procede.. as has Jeff on behalf of the Turbo Tuner.

Please don't make this a Procede vs. Turbo Tuner thread.

I think this will be helpful on what to expect for us tuning newbies. I would rather not have to troll Evo forums to get an idea of what to expect.

Thanks.

[bhvrdr]

I think this is a good question. I've been following closely to see how datalogging software for the 335i has progressed so people can post logs of stock versus modified cars.

When it comes to turbo modified cars there are three big players (and a crapload of small players)...

Boost
Fuel
Timing

The relationship between these variables is tied up in multiple simple and more complex 3D maps, most of which are interdependent.

The main enemy of any engine and most importantly the turbocharged engine is HEAT.

Oil temperatures seem to be an interesting topic. I noticed myself a 50 degree difference in oil temps when doing a long term test drive yesterday between the automatic transmission car I drove and the manual transmission car. The manual running 220 degrees with the automatic running 270 degrees. This was running them through the exact same test area with same ambient temps. Not the hugest of issues though since anyone willing to modify their 335i should at least have the sense to look at a factory guage and add oil cooling if necessary, which it would have been on one of the cars I drove.

Intake temperatures: I havent seen many logs of this at all. Keeping down intake temps is important for making power and for lengthening the life of the motor. Turbochargers that force more boost into the car (all things being equal) will require more intercooling. The difference between stock vehicle intercooling and modified vehicle intercooling efficiency would be great to see data on. I'd love to see logs.

Exhaust gas temperatures: Every manufacturer has a maximum continuous and a maximum peak exhaust gas temperature the recommend in their vehicle. No one has posted what these manufacturer specs are for the 335i but I would suspect not more than 1000 Celsius. Things that will have to be known are: Is there enough fuel being added to adequately cool the cylinders and keep EGT (exhaust gas temp) within normal limits. Is the timing spot on so that the motor is not sensing detonation and having to pull back? Is boost within its efficiency range?

All great questions and the logging software will open doors to answers that I am anxiously awaiting as I follow your guys forums in the hopes of having one of these great cars.

cheers! Mike

[DrDomer]

I appreciate the response. I know there is a wealth of info out there.

[Terry335]

Short version: If its not knocking it will last a long time.

[OpenFlash]

Originally Posted by Terry Burger

Short version: If its not knocking it will last a long time.

No. A modern engine control system will not allow for knock. Instead, it will keep trimming timing back globally until knock is squelched. The downside of this - besides being slower- is that such a car will run considerably hotter (less mechanical and thermal efficiency) than one that runs knock-free with more ignition advance.

Shiv

[e.n335]

Reliability is a good point. For me, the fact that Shiv has huge turbo tuning experience since years and the excellent PROcede hardware, offer big advantages for us PROcede users compared to other solutions. The fact, that Shiv developed and evolved the PROcede over months with his own daily driver says a lot. He explained everything he did briefly, so that also people with not that deep technical knowledge could understand the importance of timing, boost and fuel. Vishnu authenticated efficiency and reliability of their tuning in the Bathurst race.

I always would choose to buy the PROcede, as I did and ordered already. Even if my decision would be wrong, what I clearly don't expect, I can remove it without leaving a trace.

But still the reliability question remains, why ? The 335i's in Bathurst ran on lower boost pressure. Even though, Vishnu has been very concerned about EGT's and the tiny 335i turbos. I understand, that a tuning company has to show big gains in hp and torque. But why not as an option ? If Vishnu would provide "racing" maps ( boost 12.5 psi or more, corresponding to the current maps ) AND "street" maps ( max. boost 11.5 psi, like used in Bathurst ), the customers would have the choice what they want to do with their cars. Not everybody is interested in huge gains. Big gains and other pro's of the PROcede are more than enough for me.

Of course, "race" and "street" maps should be further developed and maintained in the future, so that everybody can share the results of ongoing development / improvements of the PROcede. If so, I also could choose whether I like to make more power by using the "race" map, producing more heat or opt to go for a hardware extension ( exhaust, intercooler, etc. ), keeping the temp's as low as possible. I would love to have the best ECU mod for the 335i currently available ( my point of view ) and having reliability-related options as well. Vishnu offers already a detuned map for the PROcede, +20whp, +50lbft if you ask for, but this is not what I have been looking for, long term.

The more engine parameters you can control, the more reliable the tuning could be, depending on the tuner's intentions and knowledge. So the best ECU mod would be reprogramming the unit. But this will have a lot of downsides, compared to the PROcede's capabilities. TT would never be an option for me due to the restricted functionality it provides, although users like the TT and it works. Low price and easy installation / deinstallation have no impact on quality of engine tuning. I'm not pushing a PROcede vs. Turbo Tuner discussion, just trying to point out some differences between ECU reprogramming, piggy back ECU's and plug-in boost controllers.

My $0.02.

Cheers
Eugen

[BMW_drei]

For me the bigger concern should be the mechanical parts of the powertrain (I'm a mechanical engineer, so I lean that way anyway). I trust that Shiv has done his homework and is paying close attention to the engine managementproblem, but he probably has no way of knowing for sure where the limits are in the powertrain (up to and including the pistons, rods, etc.). Particularly since these components will suffer from reduced life at the limits, and life is something that only time and use will tell.

I'm watching the modded cars, as well as BMW's design moves, to see what components can't take the higher forces involved. My concerns go to the transmission and powertrain more than engine components because the incrementally higher forces inside the engine are small compared to the rotational forces already present in stock motors. Since the slightly increased wear on the driveline might or might not be enough to take life of these components down below my target useful life (~75k miles minimum), I'm on the fence. I've experienced enough examples with my Jeep to keep these concerns up front -- with my recent rebuild on my Wrangler, I specifically weighed the benefit of higher power against replacement of the driveline, and with an offroad vehicle durability is a major factor.

[e.n335]

In general, as long as the engine power output does not exceed the numbers of the new BMW Alpina 335i, I am not concerned about other parts than the engine ...

[DrDomer]

Originally Posted by eugen.niederreiter

In general, as long as the engine power output does not exceed the numbers of the new BMW Alpina 335i, I am not concerned about other parts than the engine ...

Do you think that the design of that car took reliability into account? If so, you're saying the HP and TQ gains are similar to those of the Procede so if you stay in that ballpark you should have better reliability? Seems simplistic, but I'm the least knowledgeable here.

[BMW_drei]

Originally Posted by DrDomer

Do you think that the design of that car took reliability into account? If so, you're saying the HP and TQ gains are similar to those of the Procede so if you stay in that ballpark you should have better reliability? Seems simplistic, but I'm the least knowledgeable here.

I'm making assumptions about BMWs design practices here, but since I work in a similar field, I'm comfortable saying that it is probable that BMW looked at the reliability of the drivetrain during the design of the 335. It's in their financial interest to do so, at least during the warranty period. Since they have a long history of designing cars, they have the experience to make sound judgements, assuming they aren't pushed outside their design experience by other factors (cost is the most common).

I'm assuming Alpina covers their work with a suitable warranty, which means they will avoid overreaching the limits (at least during the warranty period). Since they work closely with BMW, I'll bet the Alpina engineers have access to the same calculations BMW did when they designed the car.

Wear and reliability is a fairly well understood engineering problem, at least in this area, so if the tuned output is roughly the same as Alpina, and Alpine has kept the same stock components, the reliability in the near term should be fine. If Alpina has changed out any part of the driveline, that opens up the possibility they were close to the limits otherwise.

[OpenFlash]

Originally Posted by eugen.niederreiter

But still the reliability question remains, why ? The 335i's in Bathurst ran on lower boost pressure. Even though, Vishnu has been very concerned about EGT's and the tiny 335i turbos. I understand, that a tuning company has to show big gains in hp and torque. But why not as an option ? If Vishnu would provide "racing" maps ( boost 12.5 psi or more, corresponding to the current maps ) AND "street" maps ( max. boost 11.5 psi, like used in Bathurst ), the customers would have the choice what they want to do with their cars. Not everybody is interested in huge gains. Big gains and other pro's of the PROcede are more than enough for me.

If we could have run the race cars at 12.5psi, we would have. Not just for power but for lower fuel consumption. During testing, we found that the higher boost we ran, the less we had to rev ou the car. With 11.5psi instead of the 8-9psi we initially tested with, the drivers would use all that extra midrange torque instead of revving it out to 7000rpm. This made the car run cooler and with lower fuel consumption. Surprised me too!

Compared to our street cars, the boost pressures we ran in the 12HR race is virtually identical above 3500rpm. The only time we ever see 12-13psi of boost with the street cars is at very low RPM. Something that race cars never see anyway.

Shiv

[Terry335]

Originally Posted by shiv@vishnu

No. A modern engine control system will not allow for knock. Instead, it will keep trimming timing back globally until knock is squelched. The downside of this - besides being slower- is that such a car will run considerably hotter (less mechanical and thermal efficiency) than one that runs knock-free with more ignition advance.

Shiv

If the 335 PCM is anything like that of a late model Corvette, it will move between a high and low octane map based on rpm, map, and the knock sensors. It's hardly a "global timing retard", it’s a targeted timing retard based on the rpm and map where the knock occurred.

Plus, the timing retard is only under limited parameters, so I doubt it would have even a noticeable impact on engine temperature.

The low octane table is usually the lowest timing will go. If it knocks at that level, its headgasket time.

[DrDomer]

Again... sounds like people don't think reliability should be an issue. Typically, do turbo engines have problems under 50,000 miles if engine management is altered to increase boost, etc? I know.. a broad question... just trying to get a feel of what we're all getting ourselves into.

[OpenFlash]

Originally Posted by Terry Burger

If the 335 PCM is anything like that of a late model Corvette, it will move between a high and low octane map based on rpm, map, and the knock sensors. It's hardly a "global timing retard", it’s a targeted timing retard based on the rpm and map where the knock occurred.

Plus, the timing retard is only under limited parameters, so I doubt it would have even a noticeable impact on engine temperature.

The low octane table is usually the lowest timing will go. If it knocks at that level, its headgasket time.

There's a huge difference between a Corvette computer and the computer in your BMW. Especially with respect to knock control. I suspect having turbochargers has something to do with this.

shiv

[Terry335]

Originally Posted by shiv@vishnu

There's a huge difference between a Corvette computer and the computer in your BMW. Especially with respect to knock control. I suspect having turbochargers has something to do with this.

shiv

I described how the Corvette system works, why don't you enlighten us on the 335 system?

[DrDomer]

Originally Posted by shiv@vishnu

There's a huge difference between a Corvette computer and the computer in your BMW. Especially with respect to knock control. I suspect having turbochargers has something to do with this.

shiv

That seemed obvious to me, but I generally don't know what I'm talking about so I didn't say anything. I need to read "how engines work for dummies".

[OpenFlash]

Originally Posted by Terry Burger

I described how the Corvette system works, why don't you enlighten us on the 335 system?

Terry-- There's plenty of info that we've posted regarding the factory ECU. Just do a search.

[lkraven]

I liked the original version of your post better, shiv.

You've tuned the Suburu's, shiv. Additionally, I imagine you've had quite a few hours looking at the 335i. Based on your experience, what do you think about likely failures or weaknesses in the drivetrain as a result of ANY boost increases?

I've got a fair amount of confidence that the Procede adequately addresses fuel, timing, and heat management issues with your tuning philosophy, but the only impact you have directly is on the signals to the ECU.

Could you shed a little light, even if it's just personal opinion, on the rest of the drivetrain with boost modifications?

[BMW_drei]

Originally Posted by shiv@vishnu

Terry-- There's plenty of info that we've posted regarding the factory ECU. Just do a search.

Less argumentatively --
I'm guessing that the Corvette chooses between 2 defined map tables based on where it has sensed knock in the past, but the BMW biases igntion retard (and other parameters...?) across the board when it senses knock?

I'm a mechanical guy, but from what I know of controls, it sounds like the BMW system is more complicated to get right but better at nailing the sweet spot than the 'vettes A or B mapping. It sounds like (please confirm...or tell me to get lost...) the BMW controller (including when the Procede is in play) self-tunes better and will optimize itself better than the Corvette?

[Terry335]

Originally Posted by BMW_drei

Less argumentatively --
I'm guessing that the Corvette chooses between 2 defined map tables based on where it has sensed knock in the past, but the BMW biases igntion retard (and other parameters...?) across the board when it senses knock?

I'm a mechanical guy, but from what I know of controls, it sounds like the BMW system is more complicated to get right but better at nailing the sweet spot than the 'vettes A or B mapping. It sounds like (please confirm...or tell me to get lost...) the BMW controller (including when the Procede is in play) self-tunes better and will optimize itself better than the Corvette?

Just to clarify on the Corvette system, the maps represent the highest and lowest amount of timing for a given RPM/MAP (ignoring transitional items). The system picks a number in-between those two tables based on knock, remembers it, and slowly tries to go back to the high table over time.

I didn't realize people had discussed the 335 knock system in great detail; I'll do a search later today.

[Doccommando]

What concerns me is oil-cooling to the turbos themselves. I haven't been down inside the engine bay of a 335, so I don't know what the situation is, but do these turbos receive adequate oil cooling? How much heat is being reflected back onto the turbos from the engine heat shielding?

The B5 S4 owners had to deal with a ton of turbo issues because of inadequate cooling (I previously owned one) and I'm hoping the 335 won't have these issues.

[stressdoc]

Alpina & Hartge both have amped engines. Long term reliability? Hard to judge, given the way that such cars are often driven.

Cooling, for both the little turbos and the 5th cylinder, seem to be major issues. Aftermarket products in that area may not be as sexy as gaining 100 ft lbs, but seem at least as important.