Also is there a way to bypass it?

 

Unless your non-sequential, no.

 

Damn. The guy who owned it previously is a retard then. How easy is it to install?

 

If you're talking about the black plastic vacuum reservoir that's down by the power steering pump, it's a bit of work to install but not impossible. Been a while since I messed with one with the engine assembled.

The car will *run* just fine without it, however the sequential system won't be able to operate properly without it.

Dale

 

Search for the various vacuum / boost hose / solenoid diagrams on the forum. It would probably be best to study them a bit so that you can see what else the previous owner "modified".

 

I vote going non-sequential. It just removes the hassle of many fried failing parts, and greatly simplifies your vacuum line setup. Of course, going single would be the prefered route, but that is a bit more of a financial investment. Removing the thermo nightmare that is the twins was my first order of business.

 

I have 122,000 miles on my car, purchased with 68,000 on it. Been sequential the whole time. Only problem I've had was one turbo control solenoid went out - that's it.

And, I have a nice, fat powerband that's awesome for the street.

Just because something can be complicated (which the sequential system really isn't as hard as people make it out to be) doesn't mean it's time to rip it all out.

Dale

 

Technically, it doesn't need to go to the stock location. As long as you can secure it properly, you can put it anywhere and just run the lines to the proper destinations. The short the vacuum line route the better.

 

So do I.

The twin turbo's were the number one failure of the FD. If Mazda would have kept it simple, I feel it would have lived in the US longer than 3 years. It developed a bad reputation quickly with high service costs and dealership maintenance woes. It wasn't the advanced suspension design or that unusual cooling system, it was the TWINS.

Your car is obviously the exception Dale. I know you are a knowleable technician. But, there are probably more threads in this section about boost issues, patterns, or transitions than any other topic.

 

I agree with Dale. I've had seq twins in some form since '93 and have only had 2 or 3 issues. Sequential twins for a general purpose/street car is the way to go IMO. The conclusions reached in the foregoing post by XLR seem to be more the assertions of its author, not necessarily fact, per se.

 

Now I have two smart vets disagreeing with me...... good challenge

I wish I could do a thread analysis of how many individuals that have issues with the operation of the twin turbo's. Whether it's their overall reliability of the turbo itself or the proccess of its boost patterns.

Maybe the twins aren't as problematic as I seem to beleive. However, they are definitely no more reliable than a single turbo setup. All proper mods and power being equal of course. I have ZERO solenoids to fail, and 3 vacuum lines to the 80 of an OEM car. This alone must hold some water....

Either way, I digress. I didn't mean to cloud OP's thread with conjecture.

 

How do you go non sequential?

 

Look under N for non-sequ ...

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/faq-3rd-gen-other-useful-links-68640/

 

Love my twins, they have served me well and so much fun.

 

Repost and resuggestion #69

Azeknightz turbo control solenoids. Make the swap. Never worry about turbo control problems.

So I don't feel completely off topic:

The stock vacuum box stores vacuum for the sequential turbo operation. If you would like to keep your super awesome 90s design sequential turbo system operational as intended, I suggest getting that mounted up and routed as designed. Otherwise you can go boring lazy I-can't-fix-my-sequential-twins status and go non sequential :P

 

have you atleast had the reliability mods for those 33K miles? i just got mine, it had 44K (year ago) when i got it 47K now. trying to get more reliability mods on it before I got all out driving with it

 

That was the first thing I did when I picked up my FD. 93 touring with original engine and 39k on the clock. As soon as it came home I had already spent about $4000 on it. That was new coolant lines, aluminum ast, water and boost gauges, downpipe, turbo control solenoids, pulsation damper, oil nozzles and lines, new gaskets for everything removed, silicone vacuum lines, and not to mention breaking a few things like the primary turbo inlet. That was expensive. Someone said it before and I'll say it with them. FD = Financial Disaster

 

Hmmm, what is this Azeknightz turbo control solenoids and Pulsation damper you speak of?

 

Google taught me what AzeKnightz is and I've added myself to the list. Thanks!
https://www.rx7club.com/group-buy-product-dev-fd-rx-7-269/custom-solenoid-rack-968956/

Now to learn about Pulsation Dampers, sounds exciting.

 

Fuel pulsation damper. This funny lil thing that sticks out the side of your primary rail and tends to leak when it gets old and cause engine fires. those turbo control solenoids are money in the bank (and out the bank cause they're not cheap!). When I first bought my rx7, even at 39k it had some dead solenoids. It would boost 7 psi in first, transition in second, but be very slow to recover from transition. I attribute my issues to bad solenoids, old vacuum lines, and bad check valves (some crumbled in my hand after removing them @.@). Now my turbos work perfectly everytime, in every gear, and are over engineered to stay working.

 

I agree, love the spool and the second turbo punch. Compare a dyno sheet of a sequential versus a non-sequential whether they be stock or after market. The difference is night and day.