TheWulf

iTrader: (4)

Smart. I'll have to remember that one.

olddragger

iTrader: (3)

Thats trick Jeff. Nice set up.
I wonder how I could do that to just make the car go into a "limp" mode or something.
OD

TheWulf

iTrader: (4)

Apparently if you cut power to the OMP it'll trigger limp mode :P

dannobre

iTrader: (3)

I have mine hooked to an AUX input that cuts the ignition if the FP drops below 50 PSI....

It's nice to be able to log the FP...it can be eye opening below 1/2 tank when things aren't setup right

TheWulf

iTrader: (4)

True that.. I wish I had my FP gauge last year. Found out in the middle of a lapping day that my fuel pump was on its way out. Would've been a lot easier if I had a FP gauge. Needless to say its on my list of things to buy soon.

TeamRX8

iTrader: (25)

Received my Aeromotive fuel line adaptor fitting today. The 1/8" NPT port has a threaded plug in it and the -6 AN port is open. Of course my fuel pressure sender unit is 1/8" NPT. If you don't intend to use the AN port be sure to also order a -6 AN O-ring boss plug to seal it.

Brettus

iTrader: (2)

don't see how that would save you . You can only dump the additional boost provided by the BC and will still have 10psi or so from your wastegate actuator.

MazdaManiac

iTrader: (3)

My mechanical boost is set for 6 PSI at the manifold.
Dropping the boost by half at that moment will give more than enough tactile feedback to lift before it blows up.

Brettus

iTrader: (2)

how did you do that ? I thought the stock actuator you provided with your kit was set at about 9psi and that your one was actually bigger

MazdaManiac

iTrader: (3)

Bigger, yes. But at a lower spring pressure.
It is a 7 PSI actuator (with no pre-load).

Brettus

iTrader: (2)

Hmmm - that raises as many questions as it answers (for me anyway)

Like - how on earth do you make 14+psi of boost up top with just a 7psi spring ?
I can't see how your BC could keep the wastgate closed enough even if you set it to 100% DC .

MazdaManiac

iTrader: (3)

What do you mean?
If there is no signal (100% DC), it won't open at all!

Did my entire explanation of lever-arm and relative diameter go completely over your head?

You can double the opening point of a mechanical system with a boost controller with no problem (though I wouldn't go much further because of granularity), as long as the lever arm is enough to stop the gate from pulling the actuator open.
Do you understand the lever idea?

TeamRX8

iTrader: (25)

Hey guys, you're muddying up the fuel pressure gauge thread with this off topic discussion, please take it over to the Turbos For Dummies thread instead

MazdaManiac

iTrader: (3)

Isn't that the paradigm for this entire site?

TeamRX8

iTrader: (25)

Yes, if I don't joke about it the I'll have to cry instead

Brettus

iTrader: (2)

At high rpm it will , but only when there is enough exhaust pressure to force it open against the spring - the diaphragm does nothing at this point (at 100% DC) because there is no air going to it .
Am I correct in this or is there something I have missed here ?

Yes - why does it matter how big the diaphram is when it is NOT providing the force to keep the WG CLOSED ? It only OPENS the WG - yes ?
What am I missing here ?
If you can explain while keeping the insults to a minimum I would appreciate that .
Perhaps a diagram might help .

MazdaManiac

iTrader: (3)

A properly sized actuator will not blow open under any circumstance.
However, the bigger the diameter, the stiffer the spring for the same opening pressure.
Pressure has more surface to work with when opening the thing and, therefore, does more work.
So, the spring must be stiffer.

Brettus

iTrader: (2)

Yes - I get this (and always did).
But you said earlier "Bigger, yes. But at a lower spring pressure.
It is a 7 PSI actuator (with no pre-load)."

Which seems to contradict what you said above .

MazdaManiac

iTrader: (3)

It opens on 7 PSI at the actuator port.
But it takes more than three times the pull on the arm to open than the regular 9 PSI actuator.

Hmm. I wondering how I can illustrate this better.

Brettus

iTrader: (2)

I get it now - thanks.

I'm intrigued as to how big this diaphram is ....

MazdaManiac

iTrader: (3)

Just a little less than 3".

Brettus

iTrader: (2)

Wow 3" is huge !
Now that I see how this all ties in together with the FP guage I gotta agree that it is a really good setup .

I get very high pressure drop across the pipework (up to 6-7psi) at high boost and high rpm . So if i have 9psi at the uim it will be 15-16psi at the turbo . I wondered if you see anything similar and if so how does it affect your large actuator ?

To the OP - Sorry about all this off topic stuff

MazdaManiac

iTrader: (3)

Holy crap!
No, I only see about 1 PSI to 1.5 or so.

That is a STUPID high loss.
Something is not right there.

Brettus

iTrader: (2)

yeah it has me a little puzzled , it has always been like that . Car goes great and makes good power though . When I tried a larger intercooler it made very little difference to the pressure drop .

gregs

iTrader: (7)

ray ill be sending a pm your way sometime later tonight..i may need 2!