[aflatau]

Well,

I thought I would start my own custom single turbo build thread. The car(e90 335i) will be going into the shop soon to start the process..

When I first start doing research I had quite a few questions I had for my self that I went out and found the answers to share with you guys:

• What turbo should I go with?

This was my first issue I needed to over come, I originally wanted todo a custom twin setup - such as GT2832rs but my fabricator said it would be a lot more costly to go that route and a pain in the ass and suggested a single setup.

From there I was concerned about boost lag, I am so use to the powerband of the current OEM twins. So I did some research and found the following turbos:

• Garret GTX3582r
• Comp CT4 6465 Billet
• PT6466

While looking trough all these options I found that the best bang for buck would be the PT6466 for the power goals I want to go with. Problem with this turbo is that it is the most lagy out of the three. But at the end of the day I decided to purchase this option. I purchased the Vband inlet and outlet housings to make a simple install and remove process.

• Do I run an external or internal wastegate?

I was concerned about which wastegate to run, due to the fact that our OEM system is an internally wastegated setup. I dug around and sent some emails to Terry and found out that an external wastegate is not an issue and to go that route.

• Upgrade the boost solenoid?

This option here is still up in the air, I was concerned about running the OEM boost solenoid due to the fact that they some times fail in open state to cause over boost. So I decided to shell out and purchase a MAC boost solenoid I got from ebay for less then $40 shipped. This here will be a trial and error process and won't know more till I get to that point in the process.

• Upgrading the BAR Map Sensor?

Since the OEM Bar Map sensor is only a 2.0 bar, and I plan on running more then 20 PSI on this single turbo, I had to find a suitable Bar map sensor. Luckly
BMS offers a plug and play harness for the N20 3.5 bar map sensor. I purchased the map sensor from ECS Tunning and ordered the harness from BMS.

• O2 Sensor Placement pre-turbo?

So with going single I have learned that you have to place the O2 sensors before the turbo, when typically you would do post placement. The reason for this is that our OEM ECU reads two separate banks, 1-3 and 4-6 for A/F ratios. If you put the O2 sensors post turbo with a single turbo it mixes the gases and throws off the A/F ratios which will cause a tuning night mare.

• What fueling am I going to run?

Well since I have an upgrade LPFP with the Walbro Intake option, I will be running a big e85 mix of atleast 70/30 and move up from there if the system can take it. I want to see what I can do with just e85 around. Hoping to reach 25-26 PSI on E85 alone, but at this point its all hopes and dreams.

• What tuning platform?

Well with the new option of open flashing, I will be running the JB4 G5 with the open flash to tune this project. This is where I will see needing the most help from Terry, I will be making a new thread on this alone about this topic.


Those are the questions of what I could think of now, I am sure during this process I will have more, and have more answers to share with you guys.

The parts I have purchased so far are

1. Exhuast head flange from RB Turbo
2. Tial MVR Wastegate
3. 3.5 Bar N20 Map Sensor
4. Plug and play harness for bar map sensor from BMS
5. PT6466 Turbo with Vband housings
6. MAC Boost Solenoid

Right now I am also currently sourcing up the raw materials for the manifold and etc.

We will be designing a top mount manifold for this turbo, which leads me to ask some questions maybe you guys can help me answer.

Air filter placement, Where do you think the best option is to place the air filter?

What do you think the best placement is for the o2 sensors with out burning them out?

I will update this thread as I go, the car should be going under the knife this weekend if I get all my parts in time.

Please if you have any questions or comments, please feel free to share.

[Eleventeen]

Originally Posted by aflatau

For those who have done a custom one off Single. Couple quick questions..

Did you go with a internal or external wastegate?

I was recommend to put the o2 sensors pre-turbo? Any reasons why?

I have the Jb4 G5 with backend flash, does any one know how the JB4 will communicate with the single if I go with an external wastegate setup?

I went with an external wastegate.

The O2 sensors must be kept in their respective banks (cylinders 1-3 and cylinders 4-6 are measured separately) A single turbo mixes the exhaust gases, so A/F ratio must be monitored pre-turbo.

The stock solenoids can be used to control the wastegate. You can run a straight flash (like modified Cobb maps) like I am currently doing or run a flash w/ JB4 G5. Obviously a flash w/ Procede also works.

[aflatau]

Originally Posted by Eleventeen

I went with an external wastegate.

The O2 sensors must be kept in their respective banks (cylinders 1-3 and cylinders 4-6 are measured separately) A single turbo mixes the exhaust gases, so A/F ratio must be monitored pre-turbo.

The stock solenoids can be used to control the wastegate. You can run a straight flash (like modified Cobb maps) like I am currently doing or run a flash w/ JB4 G5. Obviously a flash w/ Procede also works.

With the stock solenoids do I need to purchase any sort of extra parts to work with an external wastegate?

With your external wastegate which one did you go with and what pound spring do you have in there?

[OpenFlash]

I don't recommend using the stock solenoids.

[enrita]

Just ask terry...

[aflatau]

Originally Posted by shiv@vishnu

I don't recommend using the stock solenoids.

any reason why?

[OpenFlash]

Originally Posted by aflatau

any reason why?

In the frequency they are designed to operating in, they don't have a very good dynamic range. And we have had one fail when running them with pressure going through their chambers. That was enough to make us decide to cough up another $50-80 for a conventional race proven solenoid. The other concern is that they can fail in the open state causing uncontrolled boost conditional. Whereas standard solenoids almost always fail in the closed state causing underboost.

We have tuned closed to 50 n54 single turbos without a single wastegate related failure so I can't say we regret making that decision early one in the development stage 2 years ago.

[OpenFlash]

Also when putting the o2 sensors pre-turbo, make sure you use thermal isolators to reduce their operating temps. Probably overkill but worth doing.

[Eleventeen]

Originally Posted by shiv@vishnu

In the frequency they are designed to operating in, they don't have a very good dynamic range. And we have had one fail when running them with pressure going through their chambers. That was enough to make us decide to cough up another $100-150 for a conventional race proven solenoid. The other concern is that they can fail in the open state causing uncontrolled boost conditional. Whereas standard solenoids almost always fail in the closed state causing underboost.

We have tuned closed to 50 n54 single turbos without a single wastegate related failure so I can't say we regret making that decision early one in the development stage 2 years ago.

If you're using the AEM solenoid (or any of the the blue & black solenoids labeled as whatever brand), you can get them for about $40 if you purchase them under the MAC Valves P/N. They manufacture almost all of the performance boost solenoids.

[OpenFlash]

Originally Posted by Eleventeen

If you're using the AEM solenoid (or any of the the blue & black solenoids labeled as whatever brand), you can get them for about $40 if you purchase them under the MAC Valves P/N. They manufacture almost all of the performance boost solenoids.

Yep... Even more reason to not use the stock valves. The MAC valves work nicely in the 30-40hz range.

[aflatau]

Originally Posted by Eleventeen

If you're using the AEM solenoid (or any of the the blue & black solenoids labeled as whatever brand), you can get them for about $40 if you purchase them under the MAC Valves P/N. They manufacture almost all of the performance boost solenoids.

Do you got a link to that?

[aflatau]

Found it on eBay for those curious http://www.ebay.com/itm/231031755026...84.m1439.l2649

[GeorgiaTech335coupe]

Good luck with the build. Just make you have plenty of 2 things: time and money. My build has gone way over budget and taken way longer than expected.

[3000GT MR]

Easier to just buy a kit and throw it in one weekend. To each their own. I wouldn't say you would necessarily need a procede but i would go with something proven. Which right now is the procede Unless your a tuner or have one readily available then keep the JB and pioneer it. I know Cobb is capable to a point but going into higher boost levels you'll need a piggyback

[Transport3r]

would you even be able to tune it with a flash only if you're not using stock solenoids?

[aflatau]

Originally Posted by 3000GT MR

Easier to just buy a kit and throw it in one weekend. To each their own. I wouldn't say you would necessarily need a procede but i would go with something proven. Which right now is the procede Unless your a tuner or have one readily available then keep the JB and pioneer it. I know Cobb is capable to a point but going into higher boost levels you'll need a piggyback

The person who is doing the custom single turbo on my car is also a tuner. We will also be in contact with BMS to dial in the JB4 for the boost settings.

Originally Posted by Transport3r

would you even be able to tune it with a flash only if you're not using stock solenoids?

Not sure yet, this is still up in the air. It was only $40 and I thought it was a wise purchase / insurance.

[pwr hungry]

Originally Posted by aflatau

Well,

I thought I would start my own custom single turbo build thread. The car(e90 335i) will be going into the shop soon to start the process..

When I first start doing research I had quite a few questions I had for my self that I went out and found the answers to share with you guys:

• What turbo should I go with?

This was my first issue I needed to over come, I originally wanted todo a custom twin setup - such as GT2832rs but my fabricator said it would be a lot more costly to go that route and a pain in the ass and suggested a single setup.

From there I was concerned about boost lag, I am so use to the powerband of the current OEM twins. So I did some research and found the following turbos:

• Garret GTX3582r
• Comp CT4 6465 Billet
• PT6466

While looking trough all these options I found that the best bang for buck would be the PT6466 for the power goals I want to go with. Problem with this turbo is that it is the most lagy out of the three. But at the end of the day I decided to purchase this option. I purchased the Vband inlet and outlet housings to make a simple install and remove process.

• Do I run an external or internal wastegate?

I was concerned about which wastegate to run, due to the fact that our OEM system is an internally wastegated setup. I dug around and sent some emails to Terry and found out that an external wastegate is not an issue and to go that route.

• Upgrade the boost solenoid?

This option here is still up in the air, I was concerned about running the OEM boost solenoid due to the fact that they some times fail in open state to cause over boost. So I decided to shell out and purchase a MAC boost solenoid I got from ebay for less then $40 shipped. This here will be a trial and error process and won't know more till I get to that point in the process.

• Upgrading the BAR Map Sensor?

Since the OEM Bar Map sensor is only a 2.0 bar, and I plan on running more then 20 PSI on this single turbo, I had to find a suitable Bar map sensor. Luckly
BMS offers a plug and play harness for the N20 3.5 bar map sensor. I purchased the map sensor from ECS Tunning and ordered the harness from BMS.

• O2 Sensor Placement pre-turbo?

So with going single I have learned that you have to place the O2 sensors before the turbo, when typically you would do post placement. The reason for this is that our OEM ECU reads two separate banks, 1-3 and 4-6 for A/F ratios. If you put the O2 sensors post turbo with a single turbo it mixes the gases and throws off the A/F ratios which will cause a tuning night mare.

• What fueling am I going to run?

Well since I have an upgrade LPFP with the Walbro Intake option, I will be running a big e85 mix of atleast 70/30 and move up from there if the system can take it. I want to see what I can do with just e85 around. Hoping to reach 25-26 PSI on E85 alone, but at this point its all hopes and dreams.

• What tuning platform?

Well with the new option of open flashing, I will be running the JB4 G5 with the open flash to tune this project. This is where I will see needing the most help from Terry, I will be making a new thread on this alone about this topic.


Those are the questions of what I could think of now, I am sure during this process I will have more, and have more answers to share with you guys.

The parts I have purchased so far are

1. Exhuast head flange from RB Turbo
2. Tial MVR Wastegate
3. 3.5 Bar N20 Map Sensor
4. Plug and play harness for bar map sensor from BMS
5. PT6466 Turbo with Vband housings
6. MAC Boost Solenoid

Right now I am also currently sourcing up the raw materials for the manifold and etc.

We will be designing a top mount manifold for this turbo, which leads me to ask some questions maybe you guys can help me answer.

Air filter placement, Where do you think the best option is to place the air filter?

What do you think the best placement is for the o2 sensors with out burning them out?

I will update this thread as I go, the car should be going under the knife this weekend if I get all my parts in time.

Please if you have any questions or comments, please feel free to share.

Not to be a dick, but if you're still asking all of those questions, you shouldn't be "building" your own single turbo kit. Not to mention, wtf would you pick the 6466 for a one off kit when you could just buy a 6466 kit from shiv /fftec?!? I hope your pockets are deep bud, cuz everyone who's built their own ST will tell you they're in deeper than if they had just bought a kit, and they're all sorting out issues they can't seem to get rid of that you wouldn't have to deal with if you bought a kit. Best of luck though.

[BoostAddict]

This thread might be useful to you since we've basically gone through all that already. The car has been running great with no issues other than a coil back going bad. http://www.e90post.com/forums/showthread.php?t=803384

[aflatau]

Originally Posted by pwr hungry

Not to be a dick, but if you're still asking all of those questions, you shouldn't be "building" your own single turbo kit. Not to mention, wtf would you pick the 6466 for a one off kit when you could just buy a 6466 kit from shiv /fftec?!? I hope your pockets are deep bud, cuz everyone who's built their own ST will tell you they're in deeper than if they had just bought a kit, and they're all sorting out issues they can't seem to get rid of that you wouldn't have to deal with if you bought a kit. Best of luck though.

The only "building" I will be doing is sourcing up parts and driving my car to the
shop where I will be doing the install. The tuner who is doing my custom install had a 1000 whp e36. So not to worried about it, but thanks for your concern 'bud'

Originally Posted by ***********

This thread might be useful to you since we've basically gone through all that already. The car has been running great with no issues other than a coil back going bad. http://www.e90post.com/forums/showthread.php?t=803384

I have actually read that whole thread! thanks for the link man. Glad to see others doing custom work. I just recently replaced all my coil packs and swapped out my plugs with NGks less then 2k miles ago.

[BoostAddict]

Are you 6at or 6mt? With the 6at and stock stall launching the st is painful lol

[aflatau]

Originally Posted by ***********

Are you 6at or 6mt? With the 6at and stock stall launching the st is painful lol

I am a 6MT.

[NoahSamuel]

This is what I don't get about e90/92 owners. Rather than buy a proven kit that has records behind it and plenty of community support from other members with the same setup, you'd rather build a custom setup. I'm betting to save money, on top of that.

You're going to end up with an expensive custom setup that will get spanked by a fftec car. On top of that, there are so many nuisances that you haven't accounted for thus far in your thread.

Just because someone builds 1000whp e36 m3 kits doesn't mean they can do the same (or anywhere close) on a n54.


Good luck, regardless. In for final cost totals and underwhelming performance.