Speedrx8er

I just recall There was one wire at the end of the e-manangement adaptor to the PCM with
a male and female connecter. I connected them together.. Should it remain disconnected?

lurch519

to all using the greddy turbo (or any other for that matter), you need to use a recirculating BOV on the 8 simply because the car uses a MAF, or mass air flow meter, which measures the quantity of air coming into the motor and supplies the correct amount of air for that particular amount of air. so when you use a non recirculating BOV the car still thinks that X amount of air is entering the engine, not X minus what is released by the BOV. this results in the above quoted symptoms.

now i have a technical question on same subject for those in the know.

from what i can see the greddy kit puts the MAF right behind the filter. What if the MAF was relocated to just before the throttle body as it is in stock configuration, and the BOV was mounted upstream about a foot or so from the MAF.

a) would this work?

b) would it allow us to use a BOV that vented to atmosphere for the "cooler" sound, as a recirculating BOV is pretty muffled?

just my thoughts on this

MazdaManiac

iTrader: (3)

This was addressed in detail elsewhere.
You can mount the MAF in either position and there are advantages and disadvantages to both, including those you mentioned.
I have built systems for both and the tuning can be "interesting" in either case.
My main concern is idle quality since it appears that the MAF in the RX-8 is very sensitive to the quality of the airflow.

The BOV can be open to atmosphere even if it is after the MAF as long as you clamp the MAF output at zero throttle.

lurch519

by clamp at zero throttle, i assume go into the emanage map and make it tell the ecu that when the throttle is at the closed position, that there is little or no airflow past the MAF?

Greddyturbo1

Hey Mazdamaniac, the weekend is over . Is there any advantage to recirculate the BOV, would recirculating the BOV keep pressure in the compressor part and lessen lag..

MazdaManiac

iTrader: (3)

You can ask questions whenever they pop into your head! Don't wait. If I'm too busy or whatever, I'll answer when I can. Don't hold back! :p

If you have lag with the Greddy kit, it isn't surge. So, the BOV won't have much to do with it.
In any event, no it won't keep the turbo spinning at any more significant speed than it would venting to atmosphere.

If you have lag, you need to gain better control of the wastegate with a boost controller.

Greddyturbo1

Ok, so it won't help lag, but you seem to be saying that recirculating the BOV will increase the speed of the Turbo, even alittle, so wouldnt we benefit by doing this and possible prevent stalling or surging by doing this...

MazdaManiac

iTrader: (3)

It won't increase the speed any more than a BOV vented to air.
Stalling shouldn't be an issue.

Speedrx8er

Could someone tell me where teh ECm fuse is located?

zevans

Surely a recirc is slightly better than a dump valve, in terms of performance, because you are sending cool, charged air straight back into the intake, rather than dumping a load of charge (when you've already done the work to charge it) and then having to charge fresh air all over again?

How long is the stretch of intake between charged side of turbo and the BOV location? Seems like quite a volume you'd need to fill with charge again to me...

Don't most competition FI cars have recircs? (Excluding cars with anti-lag which are just plain weird)

TORacing

your stupid.

MazdaManiac

iTrader: (3)

Recirculating the air will heat it since it is already heated by the first compression cycle.

Also, the air is moving at the speed of sound. It only takes thousandths of a second to refil the pipes.

Hey Horse: Who was that meant for? :p

zevans

Yeah, Horse, why the long face? :D

I guess the I/C is after the dump valve but before the plenum then? (Obviously it's after the turbo).

I'll ask that a different way. Does the BOV depressurise the I/C?

I wondered if it would be thousands or tenths, if it's thousands then it probably doesn't make any difference, as you suggest - but my original question stands - why do competition cars have recircs?

MazdaManiac

iTrader: (3)

IC Is before the BOV. However, the air temp after the IC is still above ambient. Recirculating reheats the air.
Releasing pressure anywhere in the system drops it everywhere in the system. Air is not cement - it wont "accumulate" anywhere.

Which type of competition cars are you talking about?

Generally, if you are running really high pressures (above 20 PSI) a recirc might save you some tuning hassles on a draw-thru MAF setup.
However, I think the most compelling argument for a recirc vale in competition would be the elimination of ejected oil under the hood (and potentially on the track should a turbo bearing go bad).
Its also quieter and if it leaks under load, the metered air wont be lost.

Greddyturbo1

I might try recirculating from the BOV to one of the two lines just after the MAF, Does anyone see a problem with that...Of the two lines one is for the metering oil pump and the other is for the oil pump filler pipe..that are connected to the S1 / suction pipe...

MazdaManiac

iTrader: (3)

Those lines are not nearly large enough. You need at least a 1/2 port. I'd go for a 1" hose somewhere further down the intake pipe.
You will need a BOV with a barbed output port, too.

Greddyturbo1

I have the greddy rs BOV, I hope I don't sound stupid, but what the hell is a barbed output port, be nice and thanks.

zevans

Let's turn that round, can you think of a well-known FI class that uses atmospheric dumps?

Good reply, thanks. I don't think I thought my question through before I posted, and I see what you mean.

I know the IC doesn't take ALL the adiabatic heat out, but it's all about differences. Here's a thought though - a BOV will give you some adiabatic cooling and a recirc won't. Again it's probably minimal tho and really this all comes down to "do you want a DOOOSH or don't you?"

Anyway, I've read the rest of the thread and +1 karma to you and Philodox in particular. To rotorygod and richard paul, -I- knew what you were talking about first time and I'm not surprised you gave up. :D

I'm a bit shocked it was post #1023 before anyone mentioned area under the curve! It seems to me like Greddy have sized the turbo to deliver the mid-range punch that's missing, and peak RPM is not what this kit is about. Good, that suits me exactly - the main thing I find catches me out on the track is curves with exits that are top of 2nd / bottom of 3rd. With just a little more torque at the bottom of third you can definitely save several gearchanges a lap. I'd buy a single-turbo 7 if I was after a drag car, and it just seems it's not what the 8 is about, so they've really thought that through.

(Anyone who knows UK circuits - Radar at Angelsey is exactly the wrong radius for either gear to be comfortable - have to scream it in 2nd or rumble round in 3rd, in which case it bogs at the apex)

Speedrx8er

My BOV blow at 3000 RPM as I was stepping on the gas <-- don't seem normal.
any idea?

Silverarrow

My bov is recirced and i still get a pronounced "whoosh" so you can have both...also the bov needs to be "set" so if it is going off early adjust it.

TORacing

I swear I didn't post this it most be some glitch! That's not me.

TORacing

how do you install the E-01?

MazdaManiac

iTrader: (3)

Do you have the manual?
Just follow the instructions. What part do you need help with, specifically?

TORacing

which pressure sensor do I use know the one from the kit or the one from the e-01? where do I hook the pressure switch to the emanage or the e-01? Do I run the blue tube from the actuator to the valve, that came with the e-01, then from the valve to the port on the intake manifold?

Greddyturbo1

Mazdamaniac, thanks for help and all the guys who contribute to this forum.

I had my car out today and had a kick *** time, Ran great and did'nt stall on me once, but a slight hesitation between 2 & 3 at about 7800-8100...But runs much better..

Here's what I did , 1st I heard that if I put a Check valve between the jet fuel mettering hose and the air filter , that it will smooth out hesitation between shifts and just in general.

And 2. I was told to soften my BOV- RS because I was still hearing the whoosh and like a flutter ( from still too much air not being released) So I soften the bov just enough until I could not hear the flutter..

Well, I don't really know which one did but it sure as hell help alot.. Thanks, Hey Jeff put your 2-cents in.. And I have a complex question for you when I get A chance to really sit down and write that out.. Right now I'am going to have alittle fun with my car.. good nite...