Makenzie71

Found a full car to pull stuff from with a fresh motor...soooo...The initial list is going to be...

S5 N/A Stock Block
Stock ECU/Electronics
Full exhaust (2.5" downpipe to dual 2" ID runners to muffler)
Full intake (FMIC, hard pipes, K&N)
720cc Injectors
S-AFC
Wideband setup...or at least an AFR gauge...

Turbo is up in the air. I'll probably settle for an S4 or S5 variant for now, but I'm not opposed to making a new manifold and using a different turbo that would be more suited to my final goal.

I'm hoping that the initial setup will run about 250whp. My final goal is 350whp.

Now, are there any commonly available turbochargers that would be well suited to the 13B and for my 250~350whp range? I don't mind making a manifold for it, but I really can't throw thousands of dollars at it (really couldn't throw too many hundreds of dollars at it).

Second, will the stock air meter be able to handle the extra draw from the compressor? I've heard mention of using heavier springs for the slide...if this is needed where do I get the springs? Would it be possible to swap the NA meter out for the Turbo meter?

RotaryRocket88

iTrader: (7)

Tuning a 9.7:1 CR turbo is not going to be fun. The SAFC isn't going to have any timing control, which would go a long way towards not blowing it up. You would need a standalone or Rtek 2.x to gain that ability.

The AFM won't be a restriction in the power range you're targeting. There are cars making 350+ whp that still have a stock AFM. And you're probably going to want to use a turbo AFM from the start. It'll give you a headstart on getting the mixture right.

Makenzie71

I'll hunt a TII AFM, then. I wasn't concerned with it being restrictive...I was just worried about the slide slamming open way too soon.

The RTek is cool but it's going to be out of my reach for a while...can't afford it and getting a pda just to be able to operate it. I can handle timing the same way I did with my Supra...I'll just keep it 3~4* retarded from the baseline. Not great for performance but it'll give me some cushion. Not looking forward to AFC tuning but it won't be too bad with a wideband.

Any ideas for turbos?

I appreciate your patience with all my questions, maestro! I used to be chin deep in all this stuff but it's like starting all over again now...

KhanArtisT

iTrader: (2)

SAFC is a bad setup for an already dangerous setup because it changes the AFM reading which alters timing. I would use an adjustable FPR to get the AFR's as close as possible and keep the boost down if you have to run the stock ECU. Or run water/meth.

With the stock ECU and the 9.7:1 rotors you're going to have to run too many safeguards to make your power goals IMO. C Ludwig here put down 253whp@8psi with a streetported S5 NA-T with a Haltech.

Makenzie71

Aaron Cake pulled it off successfully with a stock ECU and S-AFC. Safeguards are fine, this will be the setup I have to work with.

Aaron Cake

iTrader: (1)

My engine is an S4 engine and the tuning method I used was "hose fuel into it so it doesn't blow up".

You need a standalone, there is no way around it. A local owner tried to do an S5 NA turbo setup using the S5 turbo and blew about 4 engines.

For 350HP, go GT35. Yeah, there are other choices but the GT35 is quite a nice turbo and a fairly standard turbo on an RX-7 these days so there is lots of support. All the manifolds are available as well as downpipes, etc. 350HP should be no problem at around 16 PSI.

Makenzie71

Aaron, I sent you a PM a couple days ago...you can ignore it. Thanks!

Then hose fuel in I will lol. It'll just be something I have to work with. I'll be trying to source another engine and will try to find a low compression TII block, but I can't really see a lot of difference between running 14psi on a low compression block and 7psi on a high compression block. I guess we'll see. I already know it'll be a feat of careful monitoring of the fuel adjustment and AFR's.

I'll look into the GT35.

I'll mention that the 350hp goal is not something I expect to reach right away. I expect to get another block and rebuild/port it to get there. 250whp is where I would like to start at.

Thanks Aaron!

RotaryRocket88

iTrader: (7)

Aaron's setup was with 9.4:1 S4 rotors, which is actually a big difference. Increased CR means the resolution you have for tuning needs to be even better. I also forgot to mention the timing changes the stock ECU makes in response to the SAFC, like KhanArtist noted. Since the SAFC tricks the ECU into supplying more fuel (by showing increased airflow), the ECU compensates by advancing timing. Not good. You can start with a turbo ECU, which has more appropriate fuel & timing maps, but you'll still have to compensate a lot for the NA rotors.

The stock turbo timing maps are a mixture of safe and aggressive. The top end in particular actually runs very aggressive timing, which is ok with the stock turbo because torque and boost begin to dip towards redline. But if your intention is to use a bigger hybrid or full turbo, you would be needing to pull something like 5-10 degrees out of the ~4500-7000 RPM range to hope to keep it safe (in addition to a lot of fuel). As an example, the stock S4 turbo ECU runs 34* lead timing (at 90-100% LOAD) at 7168 RPM. In contrast, the timing maps I've been looking at for people running bigger turbos (that can carry torque to redline) run around 18-25* (depending on boost) at the same RPM. And that's usually with lower CR rotors too. Retarding the CAS 3-4* isn't going to cut it.

Just some things to think about with the power goals you have in mind. With the limitations you'll have for tuning, I think I'd shoot for around 200 whp on a stock turbo running low boost. It might not sound as appealing, but it'll be faster than a car with a blown engine. A lower compression engine would have more potential with the limited fuel/timing adjustments you'll be able to make.

Edit: I see I took too long typing this out, and Aaron beat me to it, lol.

Makenzie71

Yeah I forgot about the 9.4 vs 9.7 thing.

Okay well then I got a big question: Can the RTek 2.1 be tuned using a laptop? I have a laptop. That eliminates some expense...and I really know absolutely nothing about PDA's. If I ditch the S-AFC, that'll free up at least $225 in my budget. I can part ways with a few of the niftier S5 parts (car's going to be parted anyway) and make up the rest to get the RTek S5 NA 2.1, which has (from what I'm reading) fully adjustable timing and fueling maps. Would that take care of this?

I'm also looking at fuel pumps and fuel pressure regulators. Do you have any suggestions as far as what I should look for there?

edit...okay well found out it is NOT tunable with a laptop but the PDA's are apparently cheap so I'm looking into them.

RotaryRocket88

iTrader: (7)

Rtek 2.x can only be used w/ a PDA, but you can get them on eBay for next to nothing. I bought a Palm M515 for $30 for mine. And the S5 NA 2.1 would give you lots of fuel & timing correction ability, but the injector preset is limited to 550/720 at the largest. So, if you wanted to go with 720s all around (or even bigger), you'll have a lot of fuel to pull from the map manually. But it can add or subtract up to 50% to/from fuel, so that's a huge range.

As for aftermarket FPRs, I can't suggest anything. I've never used anything but the stock FPR. I'm not at all an expert on all this stuff, but I'm in the process of teaching myself, so hopefully it's still good info .

Makenzie71

**** I need to read more into the fuel maps then.

If I understand it right, though, the presets are basically to give people starting points to tune from, and I should still have the ability to go in and adjust enough to compensate for larger injectors. Hopefully I'll only have to do a lot of adjusting in the low RPM area to compensate for having 720's all around.

I'll look for an M515.

RotaryRocket88

iTrader: (7)

Yeah, if you run 4x 720s on the 550/720 setting, you'll mainly need to pull fuel from the low rpm, vacuum areas of the map. The ECU will still be supplying more fuel above the secondary transition point because the primaries are firing too, but that will be just fine for your purposes. You're going to want a lot more fuel in the ~3000-8000rpm range than the stock NA fuel map will give anyway.

Makenzie71

I guess that settles it. I'll just have to rearrange my budget a bit to make the RTek get in there and work.

Makenzie71

Okay...considering a few different options here. If I port a TII manifold setup out to bolt to a 6 port N/A block, can I still operate everything with the S5 N/A ECU? (still planning on using the 2.1)

I'm asking because it really seems like it'll be a tremendous issue getting the turbo to clear the S5 N/A 6-port actuators without it trying to occupy the same space as things that separate the car from the asphalt. Won't matter so much once I get everything into the BMW but I'd like the setup running before I start the swap.

Easiest alternative I can see is that I build my own tubular manifold and put the turbo somewhere more manageable...but I don't know how compatible that would be with the stock EFI/RTek setup.

RotaryRocket88

iTrader: (7)

Sure, you can use a ported set of TII manifolds. The only difference (besides runner length) will be you'd leave the 6PI and VDI plugs disconnected, since those systems would be gone.

Makenzie71

Good, if that won't make the ECU go nutty then that'll likely be my best option. I'd really like to build my own turbo header, though...maybe later. I'll need a bigger turbo eventually, anyway.

I searched a bit and couldn't find any info...but has anyone ever pulled off a 6-port turbo WITH working 6-port actuators?

Aaron Cake

iTrader: (1)

The only way to keep the actuators working is to build your own turbo manifold. Otherwise there just isn't any space for them.

Makenzie71

Have you seen (or read of) an NA-T with working 6 ports? Would they even work? Would VDI system still be functional? I can't remember how much of that stuff works off the air pump and how much works off engine vac.

Really thinking about it, though, if I have no room for the 6-ports if I go with a stock manifold then I have no reason to keep the VDI intake. I'm going to look more into a custom manifold.

Aaron...Rotaryrocket...thanks for your patience with all my questions!

RotaryRocket88

iTrader: (7)

The 6PI & VDI work off of air pressure from the air pump. The RPM trigger points are controlled by the ECU grounding 2 solenoids on the emissions rack, which allows air from the pump to reach the actuators. There's no doubt the system would work if you keep it hooked up & have the NA manifolds. But is it necessary, or how beneficial it will be is to be seen. Keeping the aux. ports closed at low RPM would help your off-boost torque, which might be worth it with that tall geared rear end you have. No idea whether the 3800 RPM & 5200 RPM activation points would be best on a turbo application, but the Rtek does let you change those values.

Aaron Cake

iTrader: (1)

I've never seen nor read of a NA turbo with working aux ports. However, I plan to do this with my next build as the goal will be to have maximum torque available down low. I'm going to use an NA lower intake, custom make an adapter with long runners, then a TII upper intake. The exhaust manifold will be custom to move the turbo out and towards the front of the engine. It will be a relatively small turbo (GT30R) for a rotary though but I am not concerned with high RPM power as it is going into a luxury car (Cosmo).

How the VDI works under boost is a big question though. In theory it should perform the same but due to the much greater pressure ratio between the working chamber and manifold it may not. Generally speaking, simple runner and plenum style intake manifolds are considered perfectly adequate for turbo applications.

JxT

iTrader: (7)

Is it not possible to run the aux ports electronically like the method RotaryResurrection uses?

Makenzie71

Then I'll be torn between something interesting and something easy lol. Considering the rest of the project, I may go more for interesting...I just don't know where I'll put the turbo lol. Moving forward seems like the air pump would be the perfect place. I'll have plenty of room in the new engine bay so I may bring that bad boy all the way up in front of the engine.

So I'll likely be running a heavily ported S4 turbo sitting on top of a long tube header. It'll be fun.

Or I may chicken out, ditch the air pump, and pick up an entire TII intake/turbo assembly...

KhanArtisT

iTrader: (2)

The only bad thing about the S5 NA ECU + RTEK setup is the fact that the ECU still can't read boost and has no timing retard function for it. You have to be very careful when tuning the car.

Makenzie71

It doesn't have a function to automatically retard timing with boost, but it does have a fully adjustable timing map. I'll just manually set it up to retard the timing at given intervals in anticipation of given boost levels. Not exactly ideal, but the only other option is doing a bunch of rewiring to get in a TII ECU and RTek that one...or going full standalone.

KhanArtisT

iTrader: (2)

No rewiring involved unless you want a knock sensor or have power steering. Plugs right in, though you can't RTEK it since the 2.0 isn't out yet for the S5 TII.