Borg Warner S300sxe on 20b?
 

Planning out a 20b project and wanted to see if one of the S300sxe turbos would be a decent match for a 20b? Looking to make around 500-600whp between 15-20psi. I was looking at maybe a s369sxe with T4 .96 open scroll


I was running an older s360 .88 open on a street port S4 13bt making 475whp @20psi and I want something similar in response to that turbo

You'll be on mark with your given PSI; however the AR is too small. I tried the EFR 9180 .92 and it severely choked the engine and wouldn't make more power past 400/400 @9PSI even if we increased boost. That's with 3.5" exhaust too.

the SXE line would be a very nice fit for you as you have 50% more push on the turbine wheel so spool certainly won't be an issue..

you have two choices, both would work well.

the SXE 66 can make 648 rw rotary and the 69 will top out around 738.

FYI, BW will be revamping the 69 in the near future and the flow will significantly increase.

both turbos use the same 80 mm turbine wheel which is excellent for your high flowing exhaust stream. go w the 1.0 A/R.

one of the key features of the SXE family is the efficiency improvement over the EFR.

a comparison of compressor maps shows the efficiency islands are much wider than the EFRs.

for instance, take the 70% efficiency island at 3 pressure ratios (29.4 boost)......

EFR9180...................... width is 34.5 pounds per minute

SXE 69......................... width is 41 pounds per minute!

the payoff is more power and lower IATs, a win-win.

the SXE line was developed after the EFR. not particularly knocking the EFRs as they also have significant positive features as the lighter turbine wheel and uprated bearings. all good. pick your preference.

as to max power at one pressure ratio and 20 PSI limited to 60% efficiency:

SXE 66............573 & 595

SXE 69............622 & 663

this assumes your motor can drive the turbo to the edge of 60% flow. given you have a 20B i would expect it wouldn't be a problem.

Howard

bufferovrflo

You'll be on mark with your given PSI; however the AR is too small. I tried the EFR 9180 .92 and it severely choked the engine and wouldn't make more power past 400/400 @9PSI even if we increased boost. That's with 3.5" exhaust too.

Yes, but it is mainly the IWG choking exhaust flow which is going to be really important on a 20B.

You might only lose 20-60rwhp on a 13B with the IWG (based on what other set-ups lose with open dump EWG vs recirculated EWG), but add another rotor's worth of exhaust and its choke city.

I think a 20B 9180 with the 1.05AR and good priority dual 60mm wastegates would get you another 100-150rwhp (so 500-550rwhp).

I have noticed people are making more peak HP on the exact same compressor and exhaust wheel spec journal bearing BW SXE over the IWG EFR.

And this is why- internal waste gate vs external waste gate.

-edit-
on 13B highest 9180 IWG I have seen is 570rwhp (please correct me if you find higher).

on 13B highest 9180 EWG and S366 are both a little over 660rwhp.

Thanks for the great feedback! Looks like the turbo's are both great options. Wish they came with larger single scroll options. I think the 1.0 a/r turbines are twin scroll and 20b manifolds that I have seen for sale recently are single scroll

I still want to see what the EMAP readings are once you get a chance on the new ecu.

BLUE TII;

We have seen 600+ rwhp on 3 different IWG turbo cars now, the only time I have seen more on the EFR EWG is on semi pport cars( make those 650+ figures).

BLUE TII;

We have seen 600+ rwhp on 3 different IWG turbo cars now

Thanks for the correction, I hadn't seen those charts.
I will keep looking for them.

The 666rwhp S366 I was thinking of was "Neutron" on this forum- large street port and E85.

But I hear S366 has some special sauce on the compressor side compared to EFR 9180?

Thanks for the insight; after the dyno session I was definitely changing to EWG to test out the 1.05 and possibly the 1.45 AR, this will be with 4" exhaust later this year. For now I'm enjoying the hell out of this turbo! :)

Me too actually. I need to see what my fabricators schedule is like then I'll set things up with you.

No special sauce. Nuetron is putting the 9180 on at the moment actually. He also runs the 1.1 AR and a cat actually ! It's one of our twin gate ewg setups. The 9180 will make more power based on the back to backs vs s366 I have seen.

Dan I have a t4 1.05 I can swap with you when you are ready. Maybe have your fab guy add the WG runner at the same time as the emap bungs(1/8 female npt).

I would think a S300 would be too small on the hot side for a 20B.
According to BW's Matchbot, the larger AR 80mm turbine flows about 25% more than the 74mm wheel you currently have. You're going to be pushing 50% more volume through it, so it's not a great fit.
Something in the S400 range with a large A/R 83mm (T4) or medium A/R 87mm (T6) would be a better choice (150% current flow). You also have the added benefit of cast compressors that are less "peaky" with comp maps that favor high boost (EFR). People seem to neglect the importance of matching both sides of the turbo to an engine. It's easy to look a compressor map and have a good idea of how it'll work, but the hot side has more unknowns (Emap, muffler backpressure...)

Yeah, I agree; running an EFR 9180 on a 20B at 550rwhp is like running an Apex'i RX6 on a 13B at 400rwhp- stressed engine from high exhaust manifold pressure.

And the low end power still isn't as good as it could be the 9180 20B because of the compressor surge line on the big single.

Another option is twin parallel turbos to expand the exhaust side area. Most times parallel twin turbos would result in horrible spool from compressor surge lines, but there is one stand-out turbo.

Twin EFR 7163 in 0.85AR housings flow as much as a single 83mm exhaust wheel in the 1.25AR exhaust housing.

https://cimg2.ibsrv.net/gimg/www.rx7...43a70a30f2.jpg

And the 7163 compressor surge line is so good that even halved for twins it is as good as the EFR 8374 up to ~14psi boost (amazing up to 2.2PR).

https://cimg5.ibsrv.net/gimg/www.rx7...ab21e807dd.jpg


Twins good for 800rwhp on a rotary that spool like a 600rwhp single up to 14psi (but significantly worse over that boost).

They go for ~$650ea at the end of the IRL season for good used units ( I picked up a couple).

sequential. parallel is nonsense :)

The Indycar EFRs seem to be of a different breed than the rest of the line up. Because Indycars run between 18-22psig, their compressors seem especially efficient at rotary-friendly boost levels. I picked up a pair of 6758s for a 5.3L LS project for cheap from a friend at Andretti Autosports. Probably a little small for my applications due to the small .85A/R and tiny turbine, but shouldn't sweat making 650whp+. Rumor has it that BW limits the turbos to 3000 miles on the race cars, so a lot of them are removed in good condition.

I wish MatchBot could be configured for a rotary, but there's no way to really fudge the efficiency to mimic the rotary's violent exhaust.

Well I did get some numbers with the 66mm SXE with a 1.0 AR. Had some major issues with EGTs and did not cut tuning short even though I knew I should have:( Either way the 66mm SXE made 568 WHP @ 20 psi and was a major improvement in all areas compared to the old school S366.

There was no knock what so ever but ended up with low compression on all faces front and rear. Looking at the logs showed EGTs just past 2300 degrees Fahrenheit during steady state tuning which is basically the max the probes read. Have no idea what the EGTs were during actual boost pulls since the probes were melted at this point.

Pulling the motor now to see what the damage is but I am guessing housing will be reusable since there is consistent compression on all faces. Just low.

SXE 66..

here you are on the map. 20 psi (2.36 pressure ratios) and 568 rotary rwhp..

http://imagizer.imageshack.us/v2/xq90/924/85baai.jpg

your egt # sure looks amazing. often EGTs are more a function of timing than AFRs.
it would seem that your timing had to be way retarded as if it had been way advanced you would have broken some serious internals. perhaps you cycled into prevent mode w zero timing?

it might very well be you just collapsed your corner seal springs as they are the first item to react to high heat. you can easily lose 20%++ of your compression w flattened CSs.

the S300 SXE 366 is a serious turbo with approx 650 rotary potential. it also has a small (52) trim to aid mid-range as it is really a 69 with a smaller (66) inducer... note how wide the efficiency islands are on the map.

Howard

Any idea why EGTs were through the roof? What ignition system are you running?

I am running direct fire AEM Smart coils.

I do not know anything concrete as of now but I would have to guess retarded timing along with a pretty lean A/F. Cruising A/F is basically stoich, which is pretty lean for a rotary.

Just as a point of reference-

I never had a problem running high EGT at low load on my rotary as far as engine components (besides the EGT probes which did melt at one point). Did that for 15 years or so.

I ran 1,000C for cruise (because 15:1-16:1 AFR) and had it richen up with any load (like even climbing a hill on freeway). It dropped to 700C when I gave it any gas and slowly climbed back up to 800C at full load.

Got like 24-26mpg freeway.

That's exactly what I want. We need to get together over Facebook Chat with Seth (Skeese) and build out some maps. :egrin:

15-16 afr cruise.. you'll need negative split. that's what he's running.

We are to find out soon enough

Very nice set up. As the OP mentioned in post 5 what style of exhaust outlet did you go with to match your turbine housing. Turbo spec?

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Curious, how do you have the B, C, & D ground wires wired from those coils? I ask because if those wires are joinded together as a ground, you will have ignition breakup in the upper rpm's. David Hayes just recently had his wiring corrected after a recent dyno session.

You got that kind of freeway MPG with a 20b? What was your cruising timing? I get no where close to this with mine and I cruise at 15.4 A/F with negative split. I get 16MPG hwy.

Nope, I never had a 20B. Just on a 13B.

Still not as good as my stock FD though. Drove that home at 55mph (don't ask why) and damn near got 30mpg.

Honestly not sure. These coils are wired up using a c ludwig harness for the last 4 years. The only issue I have ever had with these coils is trying to run very rich on E85 at higher boost levels. With E85 it wasn't an issue. Leaned it out and ignition issues went away and power went way up.

share you injector pulse width at a specific MPH. lets get some data on this. lets see who has the lowest Inj P/w and they are getting the best MPG. i thought the way to do it was 13.5 afr and as much timing as possible, but i did some research on negative split for cruise and leaning it out as much as possible a while back, havent done it myself yet, working on tuning power right now :)

also t-von, you dont have stock ports, they help alot.

Chris originally ganged all the grounds together (he was the one who pioneered the use of these coils on a rotary after all), but soon discovered that was not the best way to do it. Ignition breakup at high boost/rpm as everyone else is mentioning. Now power ground goes directly to battery terminals and the others go to rotor housings. Not sure if you have a revised harness or not. It's easy to fix if not.

I don't have stock ports?? What makes you say that? ;) I'll just say that I don't have you typical PP setup and I'm still experimenting. My new connectors just showed up to rewire my coils. I stupidly didn't leave enough wire on the original connectors when I wired them the 1st time. As soon as I get everything hooked back up, I'll get those pulse width numbers.

Yep joining all 3 gounds is what I did too. Now I'm trying to fix that as the power of my setup never seemed right.

Thanks for the info. I definitely have a revised harness. There is a ground at the battery and the rear rotor housing.

The turbo is a bw sxe 366, t4 ar 1.0 exhaust housing but its been modified to an open t4 by the turbo shop....not a cheap mod.
It has a v-band outlet and im running a 4-inch downpipe.

:icon_tup:

Bud, I'm running this exact turbo (sxe69) on my street port 20B. At the turbine limit around 17psi... the 1.0 a/r is just too small... I need a bigger rear, but BW don't go bigger in the 300 range.

You can order a 1.1 300sx turbine housings from full race but that will still be way to small. It also more then double what the other housings cost for some reason.

So for the 20b does that mean the SXE 400 series that has up to a 1.25ar available is more suited. Or would it depend on whether your talking stock engine to modded.

Thanks for the first hand experience stokrx

For the turbine flow, I think yes.. The 300sxe69 compressor flows fantastic, if only you could get the bigger A/R!!

Not sure if a larger one could be made/modded to fit..

_Dave.

If you step up to an S400, there are different turbine wheels available. 83mm, 87mm, 96mm, & 110mm. You can look those phi charts on Borg Warner's Match-Bot, but here are some quick numbers.

An 83mm with a 1.0A/R flows about 9.4% better than a 80mm S300 with the 1.0A/R
An 83mm with a 1.1A/R flows about 13.8% better
An 87mm with a 0.9A/R flows about 18.1% better
An 83mm with a 1.25A/R flows about 22.5% better
An 87mm with a 1.0A/R flows about 26.9% better
An 87mm with a 1.1A/R flows about 31.3% better

The standard S475 comes with a 96mm 1.32A/R turbine.
That monster flows 45.8% more than the 80mm 1.0A/R

There are FOURTEEN turbine and housing combinations on the S400. Pick your poison.

With a stock port 20B what would you expect out of a 1.05AR 9174 T4 Twinscroll with EWG?

I think I may go with the S472SX-E with a 1.1 rear. Should make great power at a lower psi and will have room to grow. The response should be decent. Choosing a turbo is a pain in the arse! lol

What kinda hp and target boost are you ariming to acheve. I havent decide which turbo I plan to use for my 20b. I do have a brand new S475 with a T6 1.10AR hot side but I feel like its a overkill for my 20b. The Borg Warner S472-SXE seems interesting and a better choice for a streetport 20b.