E series 6466 build questions

[Schmidty335i]

I finally made up my mind for my hopefully final turbo upgrade. I am going to order the Speedtech Gen 2 6466 kit. I just wanted a little info if anyone could provide me with it I would be very appreciative. My main concern is turbo surge since I don't have a BOV and the turbo doesn't have a DV built in. I was thinking about buying a N54 charge pipe with a Tial BOV and this is where my mind starts thinking from my DSM days. I plan to use a MAF with my new kit and since the BOV will be downstream from it, do any of you suppose it will cause any problems during shifting since there will be air being released that was accounted for by the MAF? Or do I need to choose between having a MAF or using a BOV? Thank you for any help you can provide and if you think of any other items I should be thinking about I would love to hear them. As for boost control I am just going to use a MAC with my JB4 until i get back to an area with E85 close then i am thinking i will pick up the REFLEX.

 

[sk8]

I run without a BOV on my 135i with a 6266 and no issues so far. The tune I'm on has the MAF coded out, so can't speak on that.

I have been running without a BOV on my turbo e30 for a few years now with no issues. Yes it will surge when you left off the throttle, but I love the sound.

 

[CalvinNismo]

Could you run a diverter setup more similar to a standard N54 (with hoses)? So you vent back into the intake, but post MAF?

Or, could you attempt to emulate the S55 logic? The S55 doesn’t use a diverter, or blow off valve from the factory, apparently there is some trick wastegate logic, but I’m not too clued up.

 

[wheela]

Could you run a diverter setup more similar to a standard N54 (with hoses)? So you vent back into the intake, but post MAF?

Or, could you attempt to emulate the S55 logic? The S55 doesn’t use a diverter, or blow off valve from the factory, apparently there is some trick wastegate logic, but I’m not too clued up.

Yeah, I've read instead of closing the throttle plate on let off, s55 just cuts fuel, leaves the throttle open, and adjusts the vanos for overlap so the excess pressure just blows through the engine. I think your're right about the wastegate too, it would make sense to close that and blow through the turbine to help keep it spooled. Someone please correct me if I've butchered this too badly

 

[wheela]

Could you run a diverter setup more similar to a standard N54 (with hoses)? So you vent back into the intake, but post MAF?

Or, could you attempt to emulate the S55 logic? The S55 doesn’t use a diverter, or blow off valve from the factory, apparently there is some trick wastegate logic, but I’m not too clued up.

Have you heard if anybody has been able to do this on an n55 DME?

 

[CalvinNismo]

Have you heard if anybody has been able to do this on an n55 DME?

I haven’t, but I'm sure with the right tables it could be possible! The N55 and S55 are fairly similar. I don’t know for sure though, I’m only speculating, it would probably require a good chunk of work/development.

 

[sk8]

MHD has the overrun brap option on the n55 F series cars. Hopefully it gets added to the E series eventually.

 

[Schmidty335i]

Thank you all for the replies! I still have some time to consider what to do, I will look further into the options you guys mentioned. I just pulled into Busan south Korea and placed my order from speedtech! Got the Gen 2 6466 with a 1.0 A/R. Super excited, should have it installed in July when I get back to the states. I'll make sure to take a lot of pictures and let everyone know how it's running.

 

[wheela]

MHD has the overrun brap option on the n55 F series cars. Hopefully it gets added to the E series eventually.

Do you know if this is emulating what the s55 does with blowing excess pressure through the engine vs. burble?

 

[wheela]

Thank you all for the replies! I still have some time to consider what to do, I will look further into the options you guys mentioned. I just pulled into Busan south Korea and placed my order from speedtech! Got the Gen 2 6466 with a 1.0 A/R. Super excited, should have it installed in July when I get back to the states. I'll make sure to take a lot of pictures and let everyone know how it's running.

Awesome! I'm excited to live vicariously till I get something! I'll be waiting for a build thread!

 

[CalvinNismo]

Do you know if this is emulating what the s55 does with blowing excess pressure through the engine vs. burble?

I believe MHD (F-Series) emulates the M2 N55 brap, but it’s not actually supposed to have any performance benefit, just a sound thing. (I had previously thought it was like a very mild compressed air anti-lag, like what you’re describing.)

I’m sure us N55-E guys will get an update with some goodies soon enough! Hopefully!

 

[Schmidty335i]

Decided to move the discussion I was having with you over here to not get the other off topic. @SLOWESTN54 Thanks for the reply about the Eldor coils for the B58, I went through a ton of different coils with my normal ignition and ended up with Eldor ones. Didn't know that they were OEM on the B58, the website I was about to buy the Nexsys kit only had the non oem options available. Thanks again for letting me know about the Eldors and most of all the correct plugs!

@Torgus I think I saw somewhere on here that you have the Spec 3+ clutch I currently have a Spec 2+ with about 25k miles on it. In your opinion would you just knock out a clutch change at the same time? I was thinking about just getting the 3+ to be safe.

 

[SLOWESTN54]

No worries! Always happy to help. As for clutch, I say go with the x clutch organic twin disk. It’s what I run. Easy enough to drive, holds more power the the spec stage 3+

 

[Torgus]

Decided to move the discussion I was having with you over here to not get the other off topic. @SLOWESTN54 Thanks for the reply about the Eldor coils for the B58, I went through a ton of different coils with my normal ignition and ended up with Eldor ones. Didn't know that they were OEM on the B58, the website I was about to buy the Nexsys kit only had the non oem options available. Thanks again for letting me know about the Eldors and most of all the correct plugs!

@Torgus I think I saw somewhere on here that you have the Spec 3+ clutch I currently have a Spec 2+ with about 25k miles on it. In your opinion would you just knock out a clutch change at the same time? I was thinking about just getting the 3+ to be safe.

I think I would wait until the stage 2+ starts to slip, unless you know you are going to be making way more power than the 2+ can hold. As you are not going to be running 100% E85 or any E85 with the 6466 I would stay with the 2+. Even if you run 93 + charge pipe meth the stage 2+ I think will hold.

When my 3+ slips I will go twin disk fwiw.

 

[Schmidty335i]

Another question for anyone who knows. I want to run all hard lines for my wastegate, does anyone know if the Precision turbo uses 1/8 npt for the nipple? Also, the same for the tial wastegate and MAC solenoid, I want to use 1/8 npt to 4an adapter then use steel braided PTFE hard lines to connect everything. Thanks again for all the information you all have already provided.

 

[ap485]

Another question for anyone who knows. I want to run all hard lines for my wastegate, does anyone know if the Precision turbo uses 1/8 npt for the nipple? Also, the same for the tial wastegate and MAC solenoid, I want to use 1/8 npt to 4an adapter then use steel braided PTFE hard lines to connect everything. Thanks again for all the information you all have already provided.

Yup! It’s 1/8”npt for both turbo and wastegate. Actually, I’m running the same adapter 1/8”-4an with 4an lines.

 

[Schmidty335i]

Thanks @ap485 I appreciate it! I am going to order the parts now. Are you running a BOV with your setup? If so do you know if you have to use an additional MAC module to control it or can I just tap the intake manifold for a boost reference after the throttle blade?

 

[Schmidty335i]

Well thanks again to everyone, I just bought a 4 port MAC, BMS charge pipe with Tial BOV, the Nexsys B58 coil conversion kit, Eldor coils with the plugs that @SLOWESTN54 mentioned and all the hard plumbing and connectors for the wastegates @ap485. As always with me and the questions, I have another one... what kind of range of power with pump fuel (92 oct in Washington state) would I be looking at with my current fueling mods. I have a charge pipe methanol kit with two nozzles 5&7 CM (i use 50/50 mix) along with a fuel it stage two LPFP and a spool FX-150 HPFP. I am honestly hoping for somewhere a little north of 500whp with that setup. Then down the road after I lick my wounds from all the money I am spending now on everything I will install a Reflex and PI and see what the stock block can do before it dies.

 

[SLOWESTN54]

500 is definitely possible for pump gas with that size turbo. But I’m not we’ll versed in N55’s enough to tell you if that’s safe for the engine.

 

[Schmidty335i]

Only one way to find out I guess.... kidding. It sucks not having the octane readily available to a guy when you are willing to buy it. I miss the days when I first got my car and lived in San Diego, there was corn on pump literally a block from my house. @SLOWESTN54 how far are you from Washington? I think I am only like a few hours from the boarder where I am now. Wish I knew someone from Canada when I was still in Japan (I left in 2022) I was trying to send a R34 GTR home, but I couldn't ship it to the states because it was too new (the military would have even paid for it to get shipped home for me if I had somewhere to send it that would accept it).