Borch

SleepR1

So far, it seems to be good. I was running a 12-8-11 this morning on the way to work (I love boostin' in the mornin'). My concerns now are 1) how long before more of the Cat falls apart and 2) how low the transition hits. I'd sure love to see 12-10-12.

I assume you got your boost problem solved?

SleepR1

Technonovice, I'm @ this stage. I've replaced the 1-way check valves under the extension manifold (vacuum line, vacuum chamber, double throttle control, pressure chamber). I've replaced the turbo control solenoid, precontrol/wastegate solenoid pair. I've also replaced the charge relief valve and air bypass valve.

My secondary boost problem is mainly confined to 1st/2nd gear @ the 4500-rpm switchover point (the secondary turbo does not come online after 4500 rpm in 1st or 2nd gear). I have reliable secondary turbo boost in the remaining gears. This points squarely @ the Turbo Control Actuator (or the lines to/from the TCA).

What's involved in replacing the Turbo Control Actuator and hoses? FWIW this part is expensive--$300 from Mazdaspeed Motorsports Development (which means $600 retail from the Mazda dealer parts counter). Send me a detailed email m.lozano@comcast.net Thanks!

SleepR1

Nope see my post above. I'm getting closer though...

BoOsTin FD

TCA is very easy to replace. I replaced mine in like 10 min or less. Still didn't fix my problem. Basically all you have to do is jack the car (passenger side), slide under it and you'll see it. It's bolted on by 2 10mm or 12mm i forgot. and there is a c clip that holds the rod which opens the door on the turbo. 2 hoses behind it are also to take off. I doubt it will fix your problem, but it's possibility since you changed all the solenoids just like i did.

SleepR1

Nope still not fixed. I replaced the hoses that connect the TCA to the rat's nest, and checked the rat's nest vacuum hose (it's securely connected).

I'm thinking of swapping the charge control valve, and the vacuum chamber...

SleepR1

FWIW, my problem was a vacuum chamber completely filled with OIL! Replaced the chambers (both pressure and vacuum) with a new chambers, and the second turbo comes online properly now. I also replaced the PCV valve with a new one to prevent the vacuum chamber from filling up again. A bad PCV will pressurize the oil pan (when under boost pressure), causing an oil mess @ the filler neck, and forcing more oil through the primary turbo, thus oiling the entire intake tract. The oil will work its way through the vacuum lines, and will ultimately fill up the new vacuum chamber again.

Borch

Congrats Manny!

I need to get a new cat. I ran well at Putnam (down to 1:24's) after I dumped the pieces of bricks out of it, but it must have disintegrated a bit more because the secondary boost is acting up again.

SleepR1

midpipe! midpipe! midpipe! midpipe! midpipe! midpipe! midpipe!

MR_Rick

iTrader: (7)

well I had a similar problem, kind of. I was gettin 8-4-4. Took it to the RX-7 store and found an couple of things. My pre-cat was clogged, my pipe from the intercooler to the throttle body was cracked and 1 broken vacum line. Now I get 12-8-12 w/ a moded ecu

Borch

I had a midpipe on last year and hated it. Too noisy and too smelly.

Mr rx-7 tt

iTrader: (5)

Good thread