concerning the T piece, there is a "PSI air restriction" on the T where is supposed to be plugged to vaccum line.

Do I keep it that way or should I use a simple T ?

 

I finaly succeed pluging the boost gauge using the T with the restricter.
But it is strange:
if i accelerate slowly: never boost
if i keep 8000rpm : no boost
if i kick the accelerator pedal: for 1/2 second i got boost(5 or6PSI) and then vaccum ...
Is this normal ?

 

foot down = boost. (well thats what it should be)

light throttle cruising will not get you into boost.

Therefore it is not normal.....

As for T piece, I believe its a simple T

 

ok thanks !
for now I use the furnished T with the air restriction, I'll change later because I do not like the idea to have air restriction in the vaccum line.

How Many PSI should I get to know if my S/C is well working ?

 

i threw the T and hooked it up direct.
OD

 

Bypass valve:
Find a vacuum port on the underside of the Pettit upper intake or the lower Mazda intake, connect a single vacuum line from there to the bypass valve nipple. Do not connect anything else to that line.

Still no boost under load?
Test your boost gauge first. (with less air pressure than the gauge reads, or on another car)

If it is working.

Test the bypass valve
Remove bypass valve; clean it.
Make sure the 90 degree large "pipe" in the side of the boost gauge is screwed in completely, and use sealant or Locktite on these threads. (mine was loose once)
Testing the BP valve:
Place your hand over the large hole at 90 degrees to the nipple for all these tests.
Suck and blow on the small nipple end.
Does the piston inside the valve move?
Does it leak when it stops (when sucking or blowing)
Leaks in the bypass need to be fixed or the valve replaced.

No leaks in the bypass valve?
Test the blower without the bypass valve installed.
Plug the two large hoses where the bypass valve connects (spark plugs are the right size to plug the hoses)
You now have constant boost with no bypass; verify there is boost. (do NOT run the engine hard with the bypass removed )
Do not leave the car without a bypass valve for more than a quick test drive.

No boost?
Find the air leak on the pressure side of the blower!!!
(It must be leaking somewhere)
Any vacuum line can leak.
Gaskets can leak.
The "hump" hose can have a hole or slit. (mine has burst before)

 

Stock Pettit pulley is 8 to 10 PSI.
Big pulley is 12 to 15 PSI.

Also, is the engine ported?
A ported engine can flow more air, and might make less boost, but more power at that boost.

 

I see about 8.5 on the stock pulley..... and mine is generally all oem stuff....

 

heck i dont see but 9lbs--maybe 9.5 at high rpm/ (lim vacuum hook up) on my big pulley.
No leaks that I can tell.
Wonder why?
OD

 

Blowers and turbochargers move air. Engines present boost.

 

excuse my english but what do you mean by "engine ported " ?

 

I have "volumne"!
Cant spell it but i got it!

 

Opening the ports to let the engine flow more air.

 

Don't you have a customized lower intake?

Also. how accurate is your boost gauge?

 

That should be great !!

So How do I port the engine ?

 

i do have a slightly reworked lim--i have the pro sport vac/boost gauge. seems accurate as I verified it with a separate diag vac/boost gauge used problem shooting. Its mechanical
i did pull 365 grams/sec before reaching 8K?

?????

JMK---dont go there
OD

 

BHR ported mine...I'm told that not much material can be removed safely.

 

Phil--what is the airfilter you are running--name brand and size?
I like how yours is outside the engine bay.
Dont tell me to call Ray--get off your butt and go look!
jk old man to oldman.
OD

 

Very, very carefully, JM:

http://www.youtube.com/watch?v=kiTkv0bGvh8

http://www.youtube.com/watch?v=FY_pY40xaVc

 

It just so happens that I have a spare one on my shelf......It's a K&N RX-4140. My intake is a full 3" ID so it took a air filter with an acceptance of the OD of my intake and a diameter to fit behind the front bumper and have the cross section to allow for sufficient air flow.....This did it......Now you have to get off your *** and look up the number to see the measurement.

FYI, this is the "What Happens in Vegas" meet weekend. We have about 64 8s and 7s at the meet this year....Needless to say, I am not sitting down vegetating this weekend.

 

lol ---thanks Phil.
heres a shot of the 18 cars at Road Atlanta this w/e and the little RV we have to set in on this way above 90F day and no breezes.
18 cars --4 rx7's with the LS 1-6 swaps! One of which (not pictured) that had a really really bad off at 140+. Driver has some rib fractures, some cracked lumbar vertebra and a thoracic puncture (lungs ok). Car blew the engine and caught on fire. When the driver blew the fire suppressant system he must have twitched the steering wheel or something. No oil on the tires or anything like that. Left the track on the back straight. Sobering moment for us all.
His cage held firm--didnt move and the car did not flip.
Anyway here is the shot of all of use---cars are double deep.

https://www.rx8club.com/attachment.p...12770480938093

 

Denny - speaking of fire suppresor systems, I'm planning on adding one. Have installed one?

 

no i dont have one--i need to at least make a fire ext. mount
OD

 

My fire extinguisher mount is the hook side of velcro, glued around the fire extinguisher, laid in the carpet, behind the driver's seat.

 

do you have nozzles in the engine bay?