cavemancan

Is the BNR turbo on the Dyno thread? Whats the difference in laymans terms between the BNR and MM's 3071?

Edit:

Well after reading some more it seems the BNR flows about 10lbs more = moe powa? I also heard we might need to upgrade the greddy's intercooler if we want more then 16 psi? Also, I read issues with a 3" vs 3.5" MAF? Can anyone enlighten me?

cavemancan

Kane

iTrader: (1)

Yes, those are all issues! Lol time to hit some threads and get some intel! I can't type it all out on iPad.

MazdaManiac

iTrader: (3)

The current turbo in the MM upgrade can flow well over 50 pounds of air. I have yet to actually see a compressor flow graph for the BNR, though I can tell you that the 3 I have run into "in the wild" have made no more power than the regular GReddy turbo.

The GReddy intercooler is good to well over 40 PSI or 500 HP, whichever comes first (for two totally different reasons).

You can use ONLY a 3.375" i.d. MAF tube and expect the MAF to work properly because that is the ONLY diameter that puts the sample pickup of the MAF in the center of the tube.
At that diameter, the MAF is accurate out to about 460 g/sec of air (±40).

Is that a threat?

Brettus

iTrader: (2)

They need to modify that restritive bend /"volute" coming off the compressor...... heh

and a couple of other things .....

MazdaManiac

iTrader: (3)

You know my system has the same volute, right?

cavemancan

Charles...let's do this!

Yet? Is it really a limitation of the turbo or the Greddy system design? (Waits for Brettus to chime in on the "...restritive bend /"volute" coming off the compressor..." argument that causes MM "volute" issues)

I am guessing in this case size does not matter? I am being serious and cracking a joke.

Ok so what do I need to do to resolve this issue? Buy an AEM and modify it or something? (This is under the impression I do not go BHR which there is a 99.9% chance I will cause I trust you mongrels to take care of business!)

I have this theory that you enjoy watching MM's blow off valve release pressure. To a certain extent I do to, and pretend I understand 50% of what anyone is saying.

I am guessing your car is the testing platform for the BHR/MM turbo system.

cavemancan

So I have a whole new array of questioning. Since my blabbering up there /\/\/\ I've moved up in the world and got myself a reman from Mazda...Not to mention a few other goodies thanks to BHR, MM, and Mazmart. So here is the thing:

I talked to a budy of mine and he is willing to build me a custom Turbo kit. Tuning will be done by MM so no issues there except getting it tuned quick enough based on the obvious timing issues with online tuning. Amongest the unknowns is turbo sizing. He wants me to ask if the following turbo's would be any good in the Rx8 world:

- HOLSET HX40W: used in diesel trucks Diesel Truck Turbo and Diesel Truck Turbo
- Borgwarner EFR: AWESOME TURBO Perhaps the EFR 6758? (67mm cold...58mm hot...not sure if I know what I am saying here just repeating what I see on there sizing chart)
- EVO 8 16 g Turbo: he said he has two of these suckers in his garage so wondering if any good in our application?

I also read somewhere about internal wastegate issues. If I got the BorgWarner would this be an issue? Anything you would recommend?

I know some will advise me to read up and turbo sizing and let's be honest. I'm not dumb but that thread scared me...LMAO! Can I understand some of it...Sure...but I'm still lost a bit. Cold side...hot side...what size is best etc etc.

Additional note since you all will ask what are my goals: 350 wHP, cooling (mazmart water pump installed currently with remedy thermostat...we plan to build a v-mount rad/intercooler like MM's), capable of long racing sessions (new to this so not sure what long is...20 min?), dayly driven still, preventative measures to prevent any accidents (much like MM did with dumping boost preasure during a unforseen lean condition), etc.

Mods currently: AEM intake, BHR ignition/midpipe, greddy exhaust, ACT flywheel/clutch, Cobb on 4th NA tune, Mazmart Remedy water pump and thermostat.

TeamRX8

iTrader: (25)

turboz is serious bizness, srsly

cavemancan

Team...It's a good thing Teddie tells me your a nice guy in real life! Edit: translated your sig...trying not to stick out too much.


Everyone else...I have more infoz (lol) on the EFR Turbo mentioned above:

Compressor Specifications
Compressor Type: Forged-Milled Wheel (FMW) Extended Tip
Compressor Wheel OD (exducer): 67mm
Compressor Wheel Inducer: 53.9mm
Max Flow Rate: 49 lb/min
Built-in BOV: All EFR compressor housings incorporate an integrated BOV.
Compressor Housing: 2.5" inlet, 2.0" hose coupler outlet

Turbine Specifications
Turbine Type: Low Inertia Gamma-Ti Turbine Wheel
Turbine Wheel OD: 58mm
Stainless Steel Investment cast Housing
Turbine outlet: GT-Vband (aka small 3" vband) ~92mm OD for all EFR turbos


EFR 6758 Turbo Link







Or would a EFR 7064 be better?



I am basing these questions on the Turbo sizing thread that yielded this graph:



How do these compare to Turblown's? Turblown GT35R

If I were to guess based on what I've read the GT35R is best??

TeamRX8

iTrader: (25)

ok, have fun

Kane

iTrader: (1)

Why would the GT35R be the best?

Describe how you came to that conclusion. You are correct BTW, but knowing why is more important.

RotaryMachineRx

iTrader: (1)

Wtf dude.... what does that even mean??

Caveman posts his power level goals, the type of driving style he wants to incorporate and different turbo options; WITH flow maps, turbo dimensions and all the info you could ask for (plus some) to answer his questions and you reply with this???

I'd rather see 100 more threads started of "What exhaust is best for my Rx8?" than see you reach 13, 095 posts of that nonsense......

cavemancan

I am having trouble understanding due to limited time (at work...lol) but based on your math (no I don't understand it but again havent spent much time on it either) there is a 7lb/ min and a 51lb /min goal which would allow quick spool of the turbo plus continued efficiency all the way to redline. So we effectively know that the turbo we would like should at very least encompass either the majority of that efficiency range or in the case of personal preference either spool quicker (the 7lb/min is within the efficency range of the turbos compressor map) or provide more top end power (the 51lb/min is within the efficency range of the turbos compressor map). Idealy it would be a combination of both but that turbo does not exist based on what I've seen so far.

Subliminal message: you should have had BHR rebuild your engine!

Smartass!

Brettus

iTrader: (2)

For a 350whp goal (and quick spool) you want the smallest turbo you can find that will deliver 50lb/min at 2 PR , and the smallest turbine/housing that will adequately flow that 50lb/min .

Brettus

iTrader: (2)

please don't quote this chart - the maps for the 18g and 20 g are wrong .

cavemancan

Right...not sure what I am looking at in regards to turbine/housing sizes or how to judge them. At the very least I understand the point of smallest turbo capable of PR of 2 and 50lb/min.


Everyone...I was shown this website and it looks cool! It helps you pick the right size turbo for your application but to be honest I am not sure how to derive the figures it requires here for the calulation. Some help is appreciated...

Borg Warner MatchBot

cavemancan

I only used it for the red dots...LOL! If you have an update I would gladly edit and replace.

Kane

iTrader: (1)

Yeah, you are tracking.

Your goal flow is at a PR that is too high for your engine.

45-50lb MIN is what you should be aiming for and those turbo's you posted needed a PR of 3 or more to be efficient. Diesel turbo's are typically like that, high PR in a narrow operating range.


Ideally, getting a Variable Vane Turbo would be what you wanted.

TeamRX8

iTrader: (25)

that means he wasn't interested in hearing about it so I bowed out gracefully. Damned if I do or don't I suppose.

What he posted was a bunch of big plans when anyone knowledgeable can see he doesn't have a good grasp on the subject. I didn't want to rain on his parade and wouldn't have said anything else, but as usual some dipwad has to go and start blaming me for not doing anything more than trying to be nice about. If you're not interested in what someone has to say then only a complete f'ing idiot goes out of their way to antagonize that person, but I suppose you consider yourself smarter than this ...

999miki

Change displacement figure to 2.6 and it will start making sense. VE will be highest around peak torque, so around 6-7k rpms, then it will decline, how much depends on backpressure. Boost is obvious and after you settle on certain compressor, adjust efficiencies. Then match turbine. BSFC and AFR will directly affect calculated power.

EFR 7670 could be quite good fit for your application http://www.turbodriven.com//performa...6_wrsin=92044&

In the end, you will find out, that Borg Warner EFR stuff is oriented rather for high pressure ratios. Garrett compressors of similar dimensions are more efficient at lower PR.

For example, EFR 7670 at 50 lbs/min and 2 PR works with about 60% efficiency. GTX3076R of similar dimensions and comparable peak flow is 70% efficient at same point. GT3582R is even more efficient, as it should be, its substantially bigger compressor. On the other hand, even smaller GTX3071R operates at 60% with same requirements.

GTX3071R, GTX3076R and GT3582R meets your compressor requirements with good efficiency. Turbine sizing is bit more complicated... 82mm compressor has been proven to be little too much for GT35 turbine for rotary application, same applies to GTX3076R. Interesting would be newly released GTX3576R as it has better wheel match. Its not just about wheel sizes, but about speed at which turbine operates, and this is dependent on compressor speed in given conditions. Its very complex

cavemancan

Am I right in thinking the Borg Warner EFR 7064 would spool quicker than the GT35R? Which would provide better midrange power(I'd be willing to shift at 8k instead of going to redline...Thought I read somewhere that could aid in preventing excessive heat...prob BS)? Could they be modified to have a PR of 2 at 50lb/min? What would you have to do? I wonder if I could contact BW and see if they have a service to do just that. The reason I ask this is those turbo's have the wastegate internally and would save me money in buying an external one as well as making the system less complex?

Turblown

No reason in even talking about BW EFR turbos, no one can get their hands on them.

GTX3576R is what you want, if money is no issue

or this @ a much cheaper price

http://turblown.net/store/index.php?productID=257

we also offer it in a To4E compressor housing; no extra charge

I have all of them in stock, and ready to ship.

cavemancan

Whats the difference between the GTX3576R and the GT35R...the maps look same at first glance?


Edit: Well according to this compareson it's not worth the extra money nor would it spool a significant amount quicker in our application and you lose a little efficency up top.

cavemancan

That helped a buttload! I'm still wondering based on the above comparo with the GTX and GT if the added cost is even worth it for a smidge of quicker spool time. Not sure if it's worth almost double the money (like $700 + more).