Hey so I am collecting parts for my next turbo build. It's in an FB but I'm using a 6Port 13b motor with 3mm apex seals and everything else I'm ordering. My goal is 350hp min but really want to break 400hp. I am going to use S5 engine harness and adaptronic ECU. so here's the questions,

1. turbo. being that I'm starting from nothing what is a good turbo to go with. I really like the BNR stage 4 for an S5 but I also like the turbonetics t3 turbo, what is the best as far as just the turbo goes? or is there something better I should be getting.

2. does anyone know how hard it is to port match a turbo LIM to a 6port motor or would I be better off mounting the turbo different do it not right next to the intake like that.

3. has anyone used adaptronic ECU and how did you like it.

4. for the TB I'm looking at getting a 80mm single butterfly and an adapter Rising RPM
would this be better than say a stock TB and has anyone done this. how did you like it?

5. fuel pump. I'm sure if I looked it up I could find this out easy but while I'm posting why not ask. how many PSI am I going to need to run and any recommendations on a good fuel pump?

that is all for now as I am still in the early part of collecting parts. actually all I have now it motor 6 port intake and injectors (725cc x2 primary 1000cc x2 secondary)

I know I have a lot of questions. this is my first turbo build and I figure if I'm going to do it I'm doing it right. so any insight you may have would be greatly appreciated. Thank you

 

We have an entire Adaptronic section here FYI;

Adaptronic Engine Mgmt - AUS - RX7Club.com

You will want at least a 255lph fuel pump for 250 to 380rwhp.
Make sure you rewire it with a higher gauge power wire too.

It takes quite a lot of work to port match the T2 lim to a 6 port LIM. Honestly if I were to do a 6port turbo, I would use the stock 6 port intake manifold( have the ECU control the ports). It would be the best of all worlds, just like the Rx-8 intake manifold setup.

Turbo wise depends on how much power you want, and how much you are willing to spend.

Borg Warner S200SX 7670

Garrett T04E 60-Trim Turbocharger

Turblown Engineering TDX Series Turbochargers

Those are a few good entry level turbos.

 

what series rotors do you plan to use?

and 3mm isn't necessary, if you use the right seals.

and a stage 4 won't get you safely to 350, let alone 400 if you are running anything higher than 9.0:1 rotors. if running the non turbo 9.4-9.7:1 rotors you will have to overshoot your turbo size and run less boost.

 

Let me understand something.

9.0 = hybrid ok

9.4 or 9.7 = hybrid not ok, stick with stock S5 turbo or get a bigger aftermarket turbo

 

running pump gas even with water injection, yes. that is correct.

the higher the compression ratio is the less safe it is to run high boost, so you need a larger turbo to compensate.

keep in mind that is based off of his goals of 350whp, which is still pushing a higher stage hybrid rather hard. it's based off the principle of pump gasoline and knock suppression, you can't toss any turbo on any rotary engine and run the turbo until it runs out of air. once you move beyond the 9.0:1 ratio the rather linear curve takes a nosedive for internal knock levels in relation to boost with gasoline. boost level relates to knock, every turbo produces different amounts of air at a certain boost level without taking intake efficiency into account. airflow(lb/min) makes power, not boost level.

my rule of thumb for just premium gasoline(91AKI/ pump premium western states):
8.5:1 = 20psi
9.0:1 = 18psi
9.4:1 = 15psi
9.7:1 = 12psi
10:1 = 10psi

those i consider upper levels, or the point at which knock will destroy an engine with repeated cycles. some people have run the threshold and even surpassed it with overly conservative tuning. water injection helps the turbo engines dramatically, but i have noticed it does less for knock suppression on what i consider the high compression engines over 9.0:1, which could probably be offset by increasing the water injection but i honestly have not and don't much feel like testing that theory. it also would require more spark energy than a standard setup.

 

Has anyone tried a hx35

 

Seeing as right now im looking at series 3 rotars (9.7:1) was only planning 10-12lbs with turbonetics t3 custom ar .67 t4 fins. Though it seems i should get s5 turbo rotars to lower compression I'll be able to run a little more boost which will help with my goal of 350-400. And the 6 port factor isn't going to play too much of a roll in all this? I may have been under the miss understanding that 6 would some how increase compression

 

Thank you for the information. It's what I was looking for. Just trying to make sense of it.

I have a couple of 9.4 rotating assemblies and one 9.0. I'm kinda considering a BNR stage 1 hybrid on a dead S5, or just get an S4 unit and swap the turbine housing over (paying attention to the double heat shields if applicable). I also have a slightly bigger eBay turbo, the same as 7dust (where you have to throw the turbine housing in a BBQ to heat it up before welding, lol). It has slightly larger dimensions on both wheels and a 1.15 AR so should breath ok, even on a 9.4:1 CR.

I also have two decent stock S5 turbos that will stay stock.

From what you're saying, and if I'm understanding correctly, you shouldn't use a hybrid on any 9.4 or higher CR rotors. However it's ok on a 9.0 rotor set. But then the boost PSI is kinda limited on stock turbos where as the aftermarket ones are supposedly rated for up to 30psi (yeah right but the point is it can do higher boost than a stock S5 and not turn the air into a heat gun as much).

So what if I did this: Use the two stock S5 turbos on the two 9.4 rotating assemblies and only seek modest power (220HP or less for safety) at 10psi or less. Use 91 octane fuel and employ intercoolers of 2" or 2.5" charge piping, but not interested in water injection at this time.

Then for the 9.0 assembly, use the aftermarket turbo or the hybrid and crank up the boost to get me to my 270HP - 300HP goal. Also use a 2.5" or 3" intercooler charge pipe and maybe water injection, depending on how hard it is to reach 300HP safely.

The alternative is to combine the 9.4 rotors with the aftermarket turbo (the overshoot turbo size like you mentioned) and try the hybrid on the 9.0 assembly, keeping your rule of thumb in mind.

Lastly the 9.4 rotors are in an R5/Y 13B. The irons should handle up to 220 without breaking. The 9.0 rotors are from an FD. I'm considering swapping the FD assembly into an R5 if necessary to reach my power goals with the FD irons but I'm so new to this way of thinking I don't know what to do. Don't want to dowel pin or stud. Any suggestions?

Oh before I forget, the three vehicles getting turbos are a GSL-SE, REPU and a rotary baja. I'm looking to double the factory HP and a huge ported NA motor is not appropriate/applicable here. They all require low end torque, not high end peaky HP. I'll let someone else play with that stuff. Kinda tired of loud and no torque, you know?

GSL-SE = 270
REPU = 220
baja = 140 to 160 with lots of fast spool and low end torque (because bug engines had way more torque than HP at a much lower RPM than a rotary, and the tranny hates high RPM anyway).

Thanks!

 

GSL-SE 9.0:1 any larger stock port config, stage 1-2 hybrid turbo running higher boost(10-12psi), or a T04B turbo assembly T4 .96A/R
REPU 9.4:1 R5 port s4 turbo ~9-10psi
baja 9.4:1 3B porting(from the REPU) if you have it sub 10psi on a stock S4 turbo if you need less power but want the most torque. there's better turbo options but this should still do fine for spool with those tiny ports.

for low end response leave all the ports untouched with the exception of perhaps opening up a 3B's exhaust. the baja probably wouldn't even need a turbo but with that configuration the response should be nearly off idle. no intercooler for that should even be necessary, as long as the engine and bay temps aren't high and it isn't tracked/run at maximum loads for more than a few minutes at a time.

 

Awesome! Thanks. Just a few specs on the aftermarket turbo/engine stuff.

EMUSA T04B T4 divided 1.15AR
cold
70.00mm
54.14mm

hot
73.45mm (I think this is like a small P-trim)
63.15mm

The other turbos aren't S4, they're both S5. Is this what you meant about better turbo options for the baja? Or did you mean like a small T3 or something that would spool super fast but maybe choke out up at high RPM?

Back when this S5 turbo was in PercentSevenC's car, it literally could spool right off idle. His engine was a streetported R5 13B though. This baja engine is just stock 12A Y irons and 76 Cosmo housings with Cosmo rotating assembly. Maybe 9.2 CR rotors? They're the heavy R5 rotors anyway.

The Cosmo rotor housings have been ported up to 12AT spec. I went up about 2mm and then recreated the factory bevel. I didn't go wider and I didn't go down because they already open at T2 spec and used to close at 3B spec (tiny!). No need to open any sooner unless I want to kill my low end torque. Same goes for my intake ports (left at 12A port timing at 40 degrees). Just an FYI the exhaust sleeves are the same as GSL-SE sleeves so bigger than 3B but smaller than T2. They also have thermal reactor ports which I've blocked with a steel plate and another gasket (See below).

pic: S5 turbo on baja engine (76 Cosmo core with Y irons)


I hope the small basically stock porting will spool this turbo as fast as it spooled on PercentSevenC's streetported R5. We can only hope. Otherwise what's the point, right? I could easily go NA but then I'd need a big decent carb that won't care if it gets jostled around back there. The racing Nikki with Grose jets will work, but it's also a great candidate for boost prepping for the REPU. Can Grose jets handle boost?

 

As for the REPU, it does have some good features.

The strongest modern nitrided R5 irons I could find with 18 tension bolts.
FD tension bolts (not that it mattered much but I had some)
74 ported intakes (All four, and it's what these had stock, so made sense, oh and the intermediate iron has tall runners like a Y)
j-spec rotor housings have GSL-SE exhaust port timing and sleeves (came stock that way, left them alone for supposedly better low end torque if NA and an anti-reversion lip if turbo)
S4 NA assembly
Atkins 2mm apex seals (good idea here?)
S4 NA flywheel 24 pounds (excellent amount of weight in a chassis of this size)
225mm new Exedy disc, gonna swap to a stock pressure plate as the current centerforce feels like *** to drive (Doesn't seem to match the REPU's pedal travel which wants to engage on the floor even fully adjusted and both cylinders are fine and worked correctly on a stock pressure plate before)

Gonna do a full 3" exhaust with like three big mufflers because I have the space
MSD fuel pump
Mallory 4309 fpr
2.5" intercooler mounted down in front of the oil cooler if I can figure out how to do it. Otherwise just run without an intercooler and keep the boost down at stock levels (7psi for S5, I think?)

Then up the boost with a manual boost controller to 10PSI like PercentSevenC had... without an intercooler! Scary. The engine didn't pop. But I don't want to risk it; so if intercooler, 10psi, otherwise, stock boost.

Semi-locked dizzy set to advance only to 10 degrees, but idle will go back to 0 for good idle quality

Wanting to use the racing Nikki because it's been hogged out to 26mm primary venturis where stock Nikki size is only 20mm. Also a 76 Cosmo reverse runner manifold for the longer primary runners and better low end torque.

It's the one on the left, now with a Nikki stud pattern.


Gonna build or buy a 2.5" Nikki carb hat.

The S5 turbo is stock other than inside the rear plate it's been clearanced so the wastegate can open up more. I might also bend the lever to port out the wastegate holes. Good idea? Bad idea?

 

Oops, I realize I'm mucking up this guy's thread. If it's ok I'd like to post a few more pictures and end on the FD setup for the GSL-SE.

Here is the racing Nikki compared with another newer stripped Nikki. You can see the gap differences between the primary booster venturis on these two carbs. I hope the big venturis allow a bunch more power for the REPU, but if not, I can just throw this carb in the baja and do an NA setup because it will still perform well as an NA. Just not sure if can handle boost with Grose jets, you know?

hogged racing Nikki (bigger than a Yaw, bigger than a Sterling)


typical stripped Nikki


The REPU's 18 bolt R5 (count them) Mazda Automobiles housings with GSL-SE port timing

 

honestly just about any of your configurations will work for the lower output setups under 250 but if you want the most torque save your smaller ports and turbo for those. IIRC the Y port runners are the same as the 3B but the ports inside the engine are larger, i could be thinking backwards though as you probably have more experience with the old school engines.

a T3 flanged turbo will spool slightly faster than a T4 with the same specs but choke up quicker in the power band.

an S5 turbo in place of an S4 would work better, so yeah keep that setup. most of your response is going to come from healthy high compression engines, smaller intake port size and a decent turbo that doesn't have much drag when spun. modifying the wastegate arm on the S5 doesn't yield much so i wouldn't try doing too much and muck it up.

 

The FD setup will have a J&W manifold from Summit, a boost prepped Holley 650 DP, stock 9.0 rotors, Goopy 2mm apex seals or Atkins, S5 NA flywheel or a light steel, 46mm precision or 50mm godspeed wastegate, knockoff SSQV BOV, 2.5" or 3" intercooler, full 3" exhaust. Some kind of carb hat (cheapie off of eBay or whatever).

That's all I can think of. Thanks for reading. Anything else I should be aware of?

 

Awesome. I'll definitely keep the two Y/R5 engines as they are in the baja and REPU and do both S5 turbos. They're both healthy and start up super easy. (Even the baja did on just starting fluid before I did the 24v mod lol). Thanks!!

As for the Y vs whatever else, all Y irons had tall runners and 40 degree port closing. The 3B all had short runners and 50 degree port closing (this is what I refer to as 74 spec) so high velocity for good low end grunt (the REPU needed it) but would choke out at higher RPM. All 74 spec Hitachi carbs also had 22mm primary venrturis but separate runner manifolds so again some choking off at high RPM. The best choice is to have channels, I've found, but then it messes up the idle calibrations and is not for the faint of heart (tried it with mixed results).

The R5 varies a lot depending on year and whether it was nitrided or not. Most have tall runners and most have typical 12A 40 degree port timing. The few oddballs out there could have NO/GSL-SE/S4 NA primary port timing (shorter than 12A but close at 40 degrees I believe and can be ported to 74 spec as I've done it a couple of times) and those should not be used, especially if they are not nitrided. No point in hurting yourself twice like that. Better to get a typical Y iron and start with the better foundation, unles you need the injector bungs. But a true NO should be avoided at all cost. It even warns you with a big NO on it.

 

Earlier you asked why do a turbo in the baja? So far I've test driven it rotary powered twice, each with a different 13B and both times the low end was pathetic. Like as gutless as the old bug engine below its powerband. Only the 6 port had anything above 4k up to 7k when the Nikki secondaries opened (modded manifold to fit a Nikki on a 6 port). But the primaries of both engines were awful. I want good low end torque but won't ever go piston powered. Why when I have access to an S5 turbo and it fits so snugly next to the engine?

Ok, I won't mess with the wastgate arm. I have a feeling keeping them at sub 250HP won't require anything special like that anyway. RETed recommends it, but Percent's turbo never creeped as far as I know. That engine swallowed up every bit of boost that turbo made, even with a full 3" exhaust.

Oh and the baja will get a 2.5" muffler with maybe a 3" downpipe. The 3" DP will consist of a 3" SS u-bend in 14 gauge. We know these S5 turbos like a 3" DP but the rest of the system can be 2.5". I figure the length of a 3" u-bend will sort of mimic a typical short DP. Gonna add an O2 bung somewhere in there too.

Or the other alternative is a 2.5" DP, thus keeping the entire thing 2.5" from turbo outlet to muffler inlet, but I need the faster spool of a 3" DP while keeping noise levels under control from the single 2.5" muffler. If I could fit two mufflers back there, I'd do 3", but I only barely have the room for a single. It's a Magnaflow 5x11 offset/offset for maximum muffling. They only come in 22" length.

Is such a short 3"DP a good idea? Or keep it at one consistant size even if it means possible slower spool? Thanks.

 

One last thing. One of the turbos was rebuilt. The other is still stock and kinda loose. The rebuilt one was pretty stiff before its first test fire in the GSL-SE. I let it go through a heat cycle but didn't drive it. When it was cool enough to touch (can't remember if I had to wait), I turned the shaft and it felt a lot better. Must have broken in?

The other used turbo is so loose it can be spun just by blowing compressed air into the inlets. Now I know ball bearing turbos can do that easily, but I didn't know how well a journal bearing could.

The rebuilt turbo isn't loose enough to spin just with compressed air, but it did spool up pretty well during its test run, according to PercentSevenC. You'd rev the carb and it would spin up and then spin down with a whoooshh sound. This is all very new to me so I assume this is what they're supposed to do just free reving.

I have yet to test fire the loose turbo. I wonder if it should ultimately go in the baja? I'm looking for fast spool to make up for small ports and a small muffler. The rebuilt one can go in the REPU if it had to (gonna test drive in the GSL-SE first). Which is better? Sorry for so many questions. Total noob here.

 

most of the low end grunt is lost to the carburetors, fuel injection helps a lot with that but it's not easy to put FI on the older engines which also ironically have the best porting for torque.

both turbos should feel similar but a loose/tired turbo can actually spool slightly quicker.