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Need help with Turbo Upgrade from S362SXE

Old 12-26-18, 09:43 AM
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Need help with Turbo Upgrade from S362SXE

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....

Last edited by strokercharged95gt; 12-26-18 at 10:41 AM.
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Old 12-26-18, 07:19 PM
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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 ?
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Old 12-27-18, 07:22 AM
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Originally Posted by Turblown View Post
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 ?
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?
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Old 12-27-18, 09:45 AM
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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.
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Old 12-27-18, 11:44 AM
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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

Last edited by Howard Coleman CPR; 12-28-18 at 11:41 AM.
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Old 12-27-18, 08:30 PM
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Originally Posted by Howard Coleman CPR View Post

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 GTX3582r 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 85.

Howard
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.




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Old 12-28-18, 09:05 AM
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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.
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Old 12-29-18, 03:25 PM
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Originally Posted by strokercharged95gt View Post
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.
PM me. I'll see what I can do to help you out.
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