BigIslandSevens

iTrader: (4)

all right huys, be gentle with me! I've searched until my eyes went crossed for a answer in previouse threads but found no defenite. My problem,, full boost until 4500 rpm. falls to 5 psi. If i back out of the gas and then get back in it, sometimes it goes back to 5 psi, and others no positive pressure!? It will always go to 5 if i come back onto the primary turbo and accelerate from there. I' ve seen threads on the one way check valves for the pressure tank and some other things. We just put the Apexi intake on the car . Thats the only mod so far.( neighbor just bought it, want it to run correct first) Thanks guys !,, If anyone knows of a thread that has a solution please direct me to it.. Big time Mahalo!!

Mahjik

iTrader: (1)

Well, here is a good guide to start with:

http://www.autosportracetech.com/RX-...leshooting.htm

BigIslandSevens

iTrader: (4)

thanks Mahjik. that looks pretty informative. It sounds like it could be the double throttle among a few other things.Any good tests?

BigIslandSevens

iTrader: (4)

do you usually replace your intake manifold gaskets when you remove them? is it necessary to remove it to get to the check valves? do parts stores have the check valves if it is bad? stores in Hawaii suck! Can't even buy plugs unless i buy 10 of each!

BigIslandSevens

iTrader: (4)

Does the double throttle effect both the primary and secondary turbo system? On the site mentioned above it says that if it doesn't function it will limit boost to around 5 psi.( is that on the pri. or sec., or max overall?)

Mahjik

iTrader: (1)

Depends on the gasket. If you still have the paper type gasket, definitely replace it. Other than that, just use your best judgement. Look at it. It's a good idea to replace them unless you know they have been replaced and aren't the original gaskets.

As far as check valves, there are check valves in general automototive stores in the HELP! section. However, people have tried them and they have failed pretty quickly. If you have to replace one, I would suggest just ordering OEM valves. Other peope have suggested using Corvette check valves however I don't have any info about them.

Ray Crowe at Malloy Mazda can do some great pricing if you need to order OEM parts: 1-888-533-3400

BTW, get used to ordering parts if you plan on keeping your FD for a long time. Rarely will you find what you need at normal auto part stores.

Mahjik

iTrader: (1)

You can always try disabling the double throttle and see if that helps:

http://www.rx7turboturbo.com/robrobi...e_throttle.htm

Basically, you are just going to have to get under the hood and start checking things out. If you don't have the factory manual, grab it here:

http://www.iluvmyrx7.com/3rd_gen_manuals.htm

The manual has many testing procedures (which is about the only good thing about it).

BigIslandSevens

iTrader: (4)

Mahjik, Thanks again for your help. I do have the factory service manual. It has saved me on mine numerouse times. My 94 has a single on it so i'm learning the twins and there hoses now! I am already used to ordering parts and not spending less than a thousand at a time.(price of fun!!) I can't wait to get under and look, just wanted a good stating place. Are new gaskets made of metal? Are the mazda gasket kits/individual gaskets suitable? Any better aftermarket?