strokercharged95gt

Good Morning All

I normally post on another site, but it seems that there is a much better knowledge base here on rotaries in general. I have been mulling over a turbo change because I have gone above my original 450-500 hp goal because that just what happens.

Based on my the BW Matchbot, it looks like I am about maxing the S362SXE (0.91 AR) out as my 8,000 RPM point is right at the edge of the speed line. This all is assuming I did it correctly. (see below)

I am looking for some guidance on the best turbo to get me to 550 rwhp and maybe a little room to grow (600 max). The easiest swap would be a S366 or S369 as it should be a direct replacement. I fear these might be a bit laggy on my setup. Looking at maybe the EFR9180 or waiting on the EFR8474. Anything Garret or Precision I should be looking at?

As it stands now, the best spool I see on my top mount S362SXE is 10 psi by ~3,650, 20 psi by ~4,200, and 25 psi a few hundred RPMs higher.

Current Setup
Rx8/Adaptronics Hybrid
13bREW Conservative Bridgeport (32mm relief port), pull 14mm Hg at 1,500 RPMs.
Pineapple EP4A Exhaust Ports
2" Sch 40 Manifold/3" Downpipe/3" exhaust (top mount design)
JGS 50mm wastegate recirculated
Twin Bosch 044 pumps (2nd pump comes on at 5 psi)
8AN Feed/6AN Return with surge tank
3 Stages of Injection (1000/1000/1650), current injectors max at ~25 psi, E70, and 8,000 RPMs
Excessive LIM/FFE rails
SPEC Twin Disc/5 speed transmission
Methanol/Water Injection (Injecting 800 cc/min of water/meth @ 25 psi, pre-turbo and Greddy elbow)
Flex Fuel (E50-E70)
D585 coils, Autolite 3932 (gapped 0.20)
Usually shift between 7,800-8,200 RPMs
Leading timing 6-10 at 25 psi, 10 split
EGTs around 1625 F during a full pull

Current Matchbot




A quick log showing spool on the current top mount S362SXE from a third gear roll.



Sorry for the long winded post, just trying to think of any potential information someway may need to provide the best turbo recommendation....

Turblown

iTrader: (12)

76mm turbine wheel ? Boost response looks normal to me for your setup. Moving up to those s366/69 units will add another 500 plus to your current response( as those are 80mm turbine wheels also). Has the current setup been on the dyno ?

strokercharged95gt

It has the 76mm turbine wheel, so I will have to change the rear if moving to a 66/69. Never dyno'd the car, only street tuned. Is there any reason go with an EFR9180 for my goals, or should I be waiting on the new EFR8474?? The EFR8374 doesn't look like it has the legs for what I need. GT42 too big?

Turblown

iTrader: (12)

9180 1.05 gets my vote. It is the best choice by far, and you should not see any increase in lag. We have them in stock.

Howard Coleman

iTrader: (6)

even though you posted lots of good info i can't tell you which turbo to buy... however i can give you some addtl info that might be of help...

as you may know BW recently added to their already wide range of relatively new engineered turbos...

all the info is avail in their 2019 catalog as to inducer exducer comp maps etc.

i have found it is helpful to simplify as there are lots of numbers. i solve for the average area of the compressor and turbine wheel. generally flow follows area in current design wheels.

here are my BW 2019 numbers:

.................................................. ..................Compressor Trim...................compressor avg area....................................... turbine avg area............................... approx max rotary rw power

BW S300SXE 62................................................ .54............................................... .......6.54....................................... .................6.31/7.14......................................573 @62% eff @ 41 psi
BW EFR 8374.............................................. .......55......................................... ..............6.62................................ ........................5.91...................... ........................550 @ 68% eff @ 35 psi
BW S300SXE 63................................................ .52............................................... .......7.06....................................... ..................6.31/7.14......................................580 @58% eff
BW EFR 8474.............................................. .......66......................................... ..............7.10................................ .........................5.91..................... .........................693 @66% eff @ 35 psi
BW S300SXE 64................................................ 54.5.............................................. .......7.18....................................... .................6.31/7.14.......................................618 @62% eff @ 35 psi
BW S300SXE 66................................................ .52............................................... ........7.74...................................... ....................7.14.......................... ....................648 @ 60% eff @ 37 psi
BW EFR 9180.............................................. .......56......................................... ..............7.85................................ ...........................7.14................... ...........................656 @ 66% eff at 39 psi
BW S300SXE 69................................................ .58............................................... ........7.94...................................... ....................7.14.......................... .....................731 @ 60% eff at 35 psi
BE EFR 9274.............................................. ........62........................................ ...............8.18............................... ............................7.14.................. ............................791 @ 60% eff @ 36 psi
BW S300SXE 72................................................ 62................................................ ........8.18...................................... .....................7.14......................... .....................833 @ 60% eff @ 42 psi
BW EFR 9280.............................................. .......66......................................... ..............8.36................................ ...........................7.14................... ............................829 @ 60% eff @ 37 psi

before moving on to other interesting comparative areas a few caveats:

power numbers derived from BW comp maps. maps are generated by powering the compressor wheel w an electric motor. our "motors" may or may not be able to drive the compressor to
the end (max flow) of the map. while max power on many of the turbos is generated at a high boost number a look at the map often shows that almost the same power can be generated at a
significantly lower boost.

both Trim and Efficiency matter. lower Trim favors spool, higher Trim favors top end.

i log IAT directly from the turbo (before IC) and also at the stock location at the UIM. because it matters as to IAT i use EGT type (K) Thermocouples. they are accurate to within 5 degrees F and a few thousands of a second.
i hear about "fast acting" sensors other than thermocouples but i KNOW K Thermocouples are dead accurate and IAT is very important to keep low. first you need the data and then you need to manage. in a typical power run to 20 psi IAT out of the turbo goes from close to ambient to the 400 F in a few seconds. (one) of the reasons i use straight methanol as AI injectant is that nothing works like methanol to lower IAT. period.

yes, you can run a base fuel such as ethanol (E 85) and you will get lower IAT as there is simply more alcohol working to lower the charge air. i like the lubricity of gasoline and it is my opinion based on 6 motors run on E85 that it is not possible to properly lube the rotary internals. there is no doubt that gasoline delivers way more lubricity than alcohol. just rub the two between your fingers. further, unless you are planning to spend a lot of time above 600 a combo of gasoline and 1000 CC of meth as AI will be knock free.

while the small numbers on the comp map showing Efficiency may get lost in the shuffle they are very important. all we are trying to do to make power is get as many oxygen molecules into the motor. simply put, if they are vibrating from being heated they take up more space thereby limiting the amount and therefore offering less to burn and less power. part of the heat generated is due to slippage between the wheel and the air. obviously this is the key challenge as to wheel design. the advent of greater/cheaper computer aerodynamic modeling, ability to make the design and better materials has all propelled the turbo into another zipcode as to efficient delivery.

not only has this increased max delivery but it has also lowered IAT everywhere on the map. everywhere on the map is important. everywhere is how you get to max flow. everywhere effects the cumulative heat into the motor.

with that in mind i look at the width of efficiency islands. i decided to use 70% as it is intact on all the maps. the wider the island the better the delivery as to mitigating heat. (heat is enemy one).
i measured 70% width at 17 psi, 20 psi and 30 psi and then added the three pounds per minute together. bigger is wider/better.

SXE
62..................................107.5
63...................................103
64...................................106.75
66...................................114.5
69...................................120.5
72.....................................91.5

EFR
8374...............................92.5
8474...............................96.5
9180..............................100.5
9274.............................73.9
9280..............................63.7

another expression of efficiency is the turbo able to stop surging and start working. this is the left vertical line and the sooner the turbo starts working the better. here, smaller (pounds per minute) numbers are better.
at 17 psi:

SXE 62......................20
SXE 63.....................20.5
SXE 64.....................20
SXE 66.....................22.5
SXE 69....................24
SXE 72....................26.5

EFR 8374...............23
EFR 8474...............26.5
EFR 9180...............27.5
EFR 9274...............27
EFR 9280...............28.5

from purely an output/quality of output the SXEs, excepting the newer EFR 8474, hold a slight advantage. later design compressor housing. the EFRs probably hold a spool advantage due to the hot wheel being 40% less in weight.
i did a lot of road testing this year and found the SXE 62 to be right on the money powerwise... 488 at 20.4 psi which would calculate to 550 at 25 psi. i found not much difference in power (my .91 ran well at 8850) between the .91 and 1.0. there was a modest amount of higher backpressure and EGT with the .91. i swapped to my EFR 9180 and made 575 at 24.9 psi very rich. EGTs were almost 100 degrees less and back pressure was lower. my guess is the 80 mm hotside wheel rather than the 1.05 housing made the difference..

as to your choice... there are so many factors... for example, if your motor makes good power around 9000 spool may not be as important an issue as when you shift your motor is flowing lots of air at 6000+. if you have stock ports and your motor is all done near 7000 spool is more important as you are really low on the rpm band.

a few nice options:

SXE 66. notice the trim is 52!. promotes spool and plenty of max flow and el cheapo but a gem quality-wise
of course the new EFR 8474 looks great but i wonder about the hotside being a bit small to power the compressor and also higher EGTs and backpressure
EFR 9180 i love mine and it may be my Texas Mile turbo in 2019.
SXE 69 would be an excellent low cost alternative to the 9180.

having recently returned from the PRI here's a few nuggets...

Garrett was SOLD by Honeywell and is now a totally separate company. IMO, a big disappointment. it appeared that under Honeywell and their new President Dan Sussna they were going to be able to
tap into Honeywell's aerospace aero tech, but now, no. i continue to question the hotside sizing of their only real 500+ hp dual purpose turbo, the GTX3584r GEN 2. can a 5.17 sq inch hotside power
the compressor map to slightly over 600 rotary rwhp? the 70% island width is not great at 91.5. start of flow is at 22 at 17 psi.

Borg Warner is doing a bit of restructuring and giving the aftermarket guys more latitude as to design, a good thing looking forward.

Xona/Tial is introducing an interesting turbo near the end of the first quarter. the compressor (67.7 X 94) is 8.17 sq inches which should place it in the high 700s powerwise. the interesting component is the hot wheel. uneven vane length
similar to the typical compressor. Xona aero is a product of Tial in Michigan and rates a look later this year. i may test one against my 9180 in April/May. Xona also has a very well engineered bearing system.

so which turbo are you going to choose?

Howard

RGHTBrainDesign

Except you're forgetting the excellent Compressor to Turbine Ratio of the G42-1200, G42-1200C (compact), and G42-1450. Personally, I'm picking up a G42-1200 Compact w/ 1.28 A/R T4 Divided for my build once all is said and done. It'll be, hands down, the best turbo for a 2-rotor wanting 650whp reliably.

strokercharged95gt

Wow thanks for all the great information. I originally was leaning towards the S369SXE but the possible 500 rpm higher spool scares me a bit.

The EFR9180 looks like more than I will ever need and more with great spool. Heading to the 1/4-mile tomorrow night to see what I can do mph wise with a nearly maxed S362SXE.

If I can keep the car together, I will be putting in a order for a EFR9180 in the next few weeks.

RGHTBrainDesign

PM me. I'll see what I can do to help you out.

strokercharged95gt

Just wanted to throw some content up here because why not.

Took my REW swapped rx8 out to the track recently to do a shakedown run. I am having nasty wheel hope issues, but that is for another discussion.

Here is what a S362SXE looks like on about 22 psi (turned it down for the first pass). Long story short, I lost power in 4th, boost dropped (you can hear the wastegate shut as the car is trying to make more boost), registered a ton of knock, and the car would not run.with 0 vacuum. Saw nothing wrong with the motor, towed it 70 miles home, only to find out I blew the main vacuum line off of the UIM. Never been so happy with a vacuum leak. Compression numbers all normal.

Anyway, massive wheel-hop aside with a 2.2 60', I was still able to hit 97.13 mph in the 1/8th mile and limped it through the 1/4 mile at 12.4 @ 113.6 MPH (should of been 122mph based on the 1/8 trap). I have had it turned up to 27 psi on the street so I will have to get back to the track to truly see what this turbo can do with a full run and more boost. Still haven't found the max of this turbo. Probably going to wait on the upgrade until I max this one out. 100 mph in the 1/8th may be just a few psi away.

Leading 12-14, 10 split
22 psi
A/F ~12:1
IAT 90-140
Ethanol 62%
500 cc/min water/500 cc/min of methanol
EGT never exceeded 1600

If the car didn't lay over in 4th I am convinced I would have caught the 392 Scat Pack Charger A8. Damn automatics just get out of the hole too damn fast.

zx1441

That 2.2 60' killed your mph. Dont know what tires you had on, but If you use slicks and a clutch fluid control valve (Tilton, etc) you should be able to instantly drop your 60' to some 1.7's without touching anything else, same boost, and I bet your trap speed in the 1/8th will be over 100mph, and at the 1/4 a 25+mph back half.

KNONFS

iTrader: (14)

Looking good; glad is was a vac leak and nothing else!

strokercharged95gt

I am going to put some new urethane differential bushings in to replace the factory 110k miles, 15 year old bushings. Hopefully this can take some of the bone shaking wheel hop out of the car. It so bad that it internally shakes my radio face plate off my radio and knocks out power to my center console electronics. Tires are MT 235/60/15 Drag Radials @ 20-22 psi. On that particular launch I was at 5500 RPMs. I have tried 6000, but it spun the tires hard then wheel hopped. Launch too easy and the car falls on its face. If the bushings don't fix I may need to try a clutch valve as you stated above to let the spec twin disc kiss the flywheel a bit easier.

Gilgamesh

Sounds like you might grenade a diff pretty soon, even the serious autoxers are blowing stock diffs in Rx8s.

Most guys run bias ply slicks to keep the rear end happy, that wheel hop will kill your diff quickly.

strokercharged95gt

Stock axles as well.

strokercharged95gt

Well where do I begin.

A few nights ago I was doing some testing.

At about 6,500 RPMs in 4th gear at 24 psi, I suddenly lost power and lifted off the throttle. Heard a ticking noise. Oil pressure was good. Water temp was good. Vacuum at idle was normal. So i limped it about 8 miles home.

It was late at night so I reviewed my logs. A/F was 11.5:1 on 60 ethanol content (which is usually richer than I run it). Leading timing was 10 degree's with a 10 degree split. No abnormal knock counts in the log (didn't hear anything either).

Yesterday I did a compression test and got equal pulses on both rotors with high 90s in the rear and mid-90s in the front (been that way for years). Coils and plugs all tested normally. I drained the oil to look for bearing material and saw nothing abnormal.

Figured I either cracked an iron or cracked my turbo manifold.

This morning I took the turbo and manifold off to inspect them, both checked out normally.... Decided to peak in the exhaust ports to see if any damage was visible in the rotor housing......

and........



The exhaust sleeve folded up into the port????????? This is a junkyard housing when I got it, and I have put every bit of 10k miles of the hardest miles imaginable on it.

Thoughts???

Keep in mind that this car could start, run, idle, and drive like this.....

Howard Coleman

iTrader: (6)

you now have an exhaust port that flows like an RX8.

RXBeetle

I don't recall if you have EGT probes but a couple of pre-turbo thermocouples are cheap insurance. It's the only feedback I have that gives individual rotor feedback.
Is it possible you lost leading ignition on that rotor? Chernobyl scenario wouldn't be surprising at 0-deg off the trailing plug.

strokercharged95gt

I have an EGT probe in the rotor that blew. I would rarely go over 1650 F during long pulls, usually max of 1600-1650 F. I still have compression in that chamber. Has anyone ever seen a sleeve peel back and clog a port like that?

I checked all my coils/plugs. Everything seemed to be firing the way it should. I started the pull halfway through 3rd gear so I was only on the throttle maybe 4-5 seconds when this happened.

Howard Coleman

iTrader: (6)

i thought the liners were inconel which melts at 2450/2600 F. given you were running a bunch of ethanol your EGTs should have been right where you quote. maybe a certain Asian country is now making knock off liners. the only way you would get into the melting range would be to have a large amount of detonation which can be 3500 F... but you didn't.

strokercharged95gt

You can see right between my two markers in the graph that my RPMs laid over and I lost power. No abnormal knock there (only high knock values between shifts when I get a nice backfire). A/F was right at 11.5:1. I have done runs up much higher at much leaner mixtures without any negative effects. This is so weird, maybe when I pull the motor apart I will find something else.

Saw this from another post by RotaryEvolution "the sleeves usually only have bending and blockage issues if the pins holding them in place become loose which allows the sleeve to pivot up and into the exhaust stream which then compromises them. almost no material known on the planet will survive that scenario and amount of pressure/heat involved. when they sit in the proper position the flames travel over the surface and the material remains rather cool. the port design is actually made for the purpose that the flame has a buffer area as it expands in pretty much the same way that the sleeve is shaped." https://www.rx7club.com/rotary-drag-...e-968076/page2

The bad sleeve is loose inside the housing. Wonder if the pin broke first and caused it to get in front of the exhaust stream and melt it? Or did the melting cause the pin(s) to break?

RXBeetle

Melts at at 2450/2600F but yield is dropping like a rock above 1400F. I don't doubt that the material temperature is lower than the gas temperature, providing the sleeve is in place....

strokercharged95gt

Just need some quick advise.

Pulled the motor apart. Everything was okay except for the sleeve. I did notice some corner seals springs were collapsed on the front rotor (the one that the sleeve caved on). Maybe driving the 8 miles home knocking/ticking was the motor off balance from only firing correctly on one rotor??? That may have caused the front rotor to vibrate around and collapse those springs?? Just a theory...

The sleeve pins were too far down in the housing to be able to tack weld so I had to grind out the sleeves. The questions at hand, should I weld up the big half inch hole in the rotor housing since I plan on running without sleeves??? Where does that passage go by the way??? Lastly, my primary runners are 2" ID and without the sleeves the PPorts are 2.5" ID exit. Should I just chamfer the turbo manifold flange 1/4-inch all the way around to create a smooth transition from 2.5" ID PPort exit to 2" ID primaries???

Here is picture for help understanding.

Howard Coleman

iTrader: (6)

there is a reason Mazda went to the trouble and expense to use Inconel sleeves in the exhaust port. aluminum melts at 1221 F. suggest you pick up a sleeve.

you will gain nothing by eliminating the sleeve. while it has a larger exit area, you are going to neck it down to fit your manifold. the smallest area in a tube/runner rules.

feel free to weld the EGR hole in the sleeve as it goes nowhere in a single turbo app.

strokercharged95gt

Thanks HC. Anyone know what brand/type of exhaust sleeve is the most durable??? Thanks