eriksseven

iTrader: (6)

I just bought this turbo from another forum member. It has 10k miles on it and seemed to be in good condition. It is the stock turbo that has been machined to fit a TO4B wheel. This is the equivalent of the BNR stage I hybrid turbo. The rx7store website claims that this turbo reaches full boost by 3800RPM's and that it's good for around 315whp at 15 psi or so.

Anyways, I got home from a long week of working, and installed this turbo last night. I had the MBC hooked up, but fully 'de-compressed' so that it would be purely up to the WG and turbo as to what PSI the car would be 'boosting'.

The original owner of the turbo said that with the massively ported WG on the hybrid, the turbo would hold an even 6psi with no problems.

These are my mods:

-rebuilt and street-ported TII
-higher compression 9:4:1 N/A rotors
-full exhaust and K&N drop-in filter
-RB FCD
-MBC
-Greddy type-S BOV

I was previously running 11psi on the stock turbo with stock fuel injectors (freshly cleaned) and stock TMIC.

What I noticed after the install of the hybrid:

The turbo seemed to 'naturally' hold boost at 8psi not 6psi...?

In 1st gear, at 3800RPM's I was seeing 4psi.
In 2nd gear, at 3800RPM's I was seeing 5psi...

So, I think there's a problem here... Perhaps my twin-scroll is always open? The only thing is though, I didn't mess with my twin scroll actuator or any of the vaccumn lines. So it hasn't changed at all from my stock turbo. My stock turbo definitely didn't lag this bad though.

Is it characteristic for a slightly larger hybrid to have a noticable increase in lag? In comparison to the stock turbo at 11psi vs. the hybrid at 8spi, the stock turbo had a lot less lag, but the hybrid pulls harder past 5000RPM's...

Anyone care to comment?

Also, in case anyone's worried about me blowing up my motor. In a couple minutes I'm going to be installing my Walbro 255 fuel pump, Greddy 720cc secondary injectors and my Apexi S-AFC.

But much to my delight, with stock fuel my narrow-band A/F gauge reads 2 clicks in the rich at WOT and this is confirmed by the flames coming out of the exhaust each time I shift.

RotaryEvolution

iTrader: (30)

hybrids tend to spool a little slower than stock turbos, i have a similar hybrid and i noticed that it spools slightly slower.

as for the full boost potential at the rated RPM, put the car in 4th and then do the test. their ratings are also only for stock boost levels (5.5PSI at 3800RPMS), you won't see full boost til at least 4500-5000RPMS with free flowing exhaust.


as far as the "massively ported wastegate", it sounds not massive enough. i ported my WG myself and it holds steady at 6PSI. this is all relative to what you want from the engine though, there is no need to port more if you don't plan on running less than your current boost levels.

eriksseven

iTrader: (6)

Thanks for the quick response. I figured the term 'massive' was a little over-kill, lol, but to put it into perspective, my stock turbo's WG was ported to the edge of the flapper and this one's got a bigger flapper welded on and ported to match.

Thanks for the advice/info.

I'll post after I've got all the fuel mods installed and let you guys know how big of a difference this turbo makes at 13psi...

eriksseven

iTrader: (6)

Quick question about the S-AFC install; I've heard people say (for turbo's) to actually tap into the boost sensor and not the TPS...? What exactly does this mean? (practically)

RX_AV8TR

Cool, you know that was my very first turbo upgrade. Don't worry, that's exactly how it's suppose to work, the TO4B is a big compressor compared to the stock TO3. The lag you describe sounds about right, even after you upgrade fuel and install the boost controller the lag will be much larger than factory.
You can check the scroll actuator by accelerating the car from the throttle cable assembly and looking at the actuator, it should open up at 2,700rpm, you'll see the shaft move.

ilike2eatricers

You can do what many hybrid people have done is to drill a hole a on the actuator arm closer to the actuator to put more tension on the wg spring so you get less lag. The extra power of the hybrid has been known to overpower the wg flapper door causing some lag.

RotaryEvolution

iTrader: (30)

i didn't notice any lag but i did notice that i can't raise my boost past 7psi due to the lack of tension on the servo arm. the larger turbos do tend to need more tension because they will push the flapper open under boost.

hooking the SAFC to the boost sensor just causes the fuel enrichment to come on with boost rather than TPS inputs, it is a better way to hook up the SAFC IMO.

to get a quicker spooling turbo you need a larger hot side compressor wheel, which really is not possible with the stock turbo(hybrids).

eriksseven

iTrader: (6)

So you literally just "drill a hole" on the actuator arm of the WG? What diameter should the hole be? And it's really just a hole, nothing goes into it or anything?

Also, about the boost sensor instead of the TPS, is there a wire for it on the ECU? Or do I have to run a wire into the engine bay or something?

Thanks for the good info people,

RotaryEvolution

iTrader: (30)

the hole is for the wastegate flapper arm to attach to, basically you drill a new hole further up the rod to put more tension on the arm to keep it tightly closed.

you ONLY need to do this is you are having lack of boost or a really noticable lag in spooling of the turbo.

also to note, if you have a BNR or panspeed turbo they should already be modified with an andjustable arm, if you look at the wastegate servo rod it should have a weld on it and a nut/threaded rod which means the length can be adjusted. you can also do this method rather than just drilling a new hole in the rod, you can either cut and center drill and tap the rod and install a threaded rod with locknuts or you can cut and reweld a threaded rod onto the existing rod in a short section of it that you cut out.

eriksseven

iTrader: (6)

^ cool.

Any info on how I connect to the boost sensor?

thanks Karack,

RotaryEvolution

iTrader: (30)

you can splice it in at circuit 2B at the ECU, it is a Brown/red tracer wire.

eriksseven

iTrader: (6)

I know it's kind of n00b to be asking this question (because I know it's been covered many times, in many ways), but, when looking at the s4 TII ECU (N333), there are 3 plugs going into it; the biggest plug has 24 wires going into it, the other two have 10 wires and 18 wires going into them... When connecting the S-AFC, am I dealing with only the largest (24 wire) plug? If so, the only brown and red wire going into it is on the top row, 3rd from the left side. There is also a brown and red wire going into the 18 wire plug, in the lower right-hand corner...

Sorry for the n00b questions, but I must say, Karack, you are 'clutch', lol.

RotaryEvolution

iTrader: (30)

found this pic in the FAQ thread for easy reference:



the middle sized plug it is the lower right hand one labaled MAP sensor in the picture.




and you're welcome.

eriksseven

iTrader: (6)

Looking at the diagram found on this link: http://www.1300cc.com/howto/how2/safc.htm , it is starting to make sense. It does show the 10pt, 18pt and 24pt connections, but they're in THAT order... On the N333 ecu they're 24pt, 10pt and 18pt (at least looking at it from my persective). Is this diagram still of use?

thanks, lol

eriksseven

iTrader: (6)

^ ooh, perfect... Thanks man. I'll post back with my install results.

RotaryEvolution

iTrader: (30)

cool

NZConvertible

Max boost is determined by many other factors besides the turbo itself. Every part on the intake and exhaust systems, plus the engine itself, will affect how much boost the turbo can make. Unless the car the turbo came off was identical to your, it won't necessarily make the same boost on your car.

It is easily checked by following the procedure on page 4B-54 of the FSM.

Neither of those indicate you're running rich enough at fill load. Narrow-band sensor readings should never be trusted as a safe way to measure full-load mixtures, and "two clicks in the rich" does not sound rich enough anyway. Flames after a shift mean simply mean the trailing throttle mixtures are rich, not full-load mixtures.

eriksseven

iTrader: (6)

^ alright, thanks NZ

I noticed that the ECU diagram that you (thankfully) posted (Karack) doesn't have the RPM signal 'pin' or wire labeled, but the diagram on the 1300cc website has it labeled at "1X", this is where I'm going to tap in, unless someone suggests otherwise.

RotaryEvolution

iTrader: (30)

that diagram is correct:



the lower left one on the 24pin connector is the tach signal wire you will patch in for the SAFC.

edit: it is a Blue wire with a yellow tracer.

eriksseven

iTrader: (6)

shoot... I messed something up, lol (sigh)

I got the wiring all hooked up and went to start the car; it cranked and started to fire, before flooding ruthlessly. I don't know which wire I hooked up incorrectly, but SOMETHING's messed up. To confirm, I turned off my fuel pump and cranked, it turned over but as soon as I turned the pump back on, it sputtered and died as a nice puff of fuel filled exhaust smoke came out the tail-pipe...

As of righ now, I'm going to disconnect everything and start over.

Anyone have any guesses on where I got the wiring wrong?

hondahater

iTrader: (2)

well you may want to make sure you set it up correctly first with just the power on. Like do you have it set on flap etc....

RotaryEvolution

iTrader: (30)

is the SAFC used or new? it could have someone elses maps loaded. initialize it and reset all of the settings as per the instructions on 1300cc.com and try it again.

if it still doesn't work right then it is possible you have something hooked up incorrectly or backwards, be sure you have the MAF sensor cut wires hooked up correctly and the inputs and outputs are on the correct sides of the wire.

eriksseven

iTrader: (6)

I replaced the stock connection on the AFM and started the car. Everything worked normally...

Except there was no power to the S-AFC. So, even if the yellow and white 'air flow signal input and output' wires were hooked up correctly, if there's no POWER to the unit, the loop (or whatever) won't work, causing the AFM to be disabled, correct?

I spliced the 'red' power wire into the blue and white wire coming from the ECU 'spot' 3J.

For ground(s) I used... (let me check)

eriksseven

iTrader: (6)

I spliced into the ground wires into the ECU spot 2C.

RotaryEvolution

iTrader: (30)

3I is where the power wire needs to go, not sure on the amperage rating of the 3J circuit but if the car is still not firing up then check the fuses and swap the power wire from the SAFC to the 3I circuit.

the SAFC defaults when it is not powered on causing a feedthrough so the AFM signal is not corrected and the engine will run fine.