5 psi/94 RX7

[kwiktsi]

Hello all, first post here. I have a 94 RX that needed turbos when I got it, I just got done with the swap and took it for a ride. The car is hitting 5psi and holding there. It is an ugh AUTO car (for the time being) if that matters. I am going to be setting it up with my MBC soon, but just wanted to get it running preperly first. Is there anything common to look for- maybe the sequential setup is not working properly or something? I was thinking of just going parallel with the turbos once I put the MBC in it- which would solve any sequential problems anyway, but I don't know how bad lag will be with the auto and as mentioned, I prefer to get it running "right" first before modding it.. Any advice would be appreciated. Thanks.
Joe

[kwiktsi]

OK, just spent more time driving it (my fiancee was driving the first time, so I couldn't get a good idea of what it is doing). It goes to 5 psi for a couple seconds then drops to 0 and stays there. I am thinking the exhaust flapper isn't opening for the rear turbo and once the butterfly in the outlet pipe (y pipe) opens, it is just pushing all the air right out the rear turbo. Does this make sense? Where should I look from here? Thanks again.

[AusTexRex]

Check your waste gate setup. If that's not it start pressure testing and find the massive pressure leak you have.

[kwiktsi]

Def. not a leak somewhere after the turbos (IC hoses are all good, etc.- first thing I checked). The wastegates are not frozen open or anything, they are moving freely- I just downloaded the vacuum diagram for it though and I will be checking to make sure they are hooked up properly. I spoke with the previous owner about it and it worked prior to going to the dealer for a motor swap- so anything is possible . Thanks.
Joe

Originally Posted by AusTexRex Check your waste gate setup. If that's not it start pressure testing and find the massive pressure leak you have.

[FadedFD]

How many miles does your 94 have? Are you still running a stock exhaust system? It could be that you have clogged cats. I was having that same exact problem with my 93 R1 with about 115k on the stock cats and new motor and turbos with about 4k on them. Once I went high flow and DP the problem was gone. But big tip is get an aftermarket ECU so you can run those mods safely. A MBC is smart to keep it at 10 PSI. Make sure it dosen't spike since you don't have a fuel computer to compensate for the extra boost.

Justin

[kwiktsi]

Wow, talk about a ressurection . I don't even own the car anymore lol. Anyway, just for future readers- the problem was the cat- sort of. The previous owner told me he had gutted it, so I kept thinking there was no way it was that. After jacking the car up and feeling the exhaust (looking for hot/cold spots) while it was running, I realized he did gut it- BUT he must have done it on the car because there were several chunks from it plugging the inlet to the muffler!!!! Some people need to just put the tools away and let a professional work on their stuff...
Joe

[FadedFD]

Wow I didin't realize how old this post was. It was still on the first page of the tech support and seemed like the problem wasn't solved yet lol. My bad

Justin