Coulthard Fan-Give us the lowdown....Power, reliability, etc. Where did you get them? Worth it?

 

I know you posted that throttle response was better, but have you since dynoed them? Have they been reliable?

 

They have been awesome and 100% reliable, not once has the boost been anything but perfect. I've had the 99 turbos for about a year now and I think they are the best mod I've done so far. The car just feeeeeels better... its pretty subjective without numbers to back it up. My G-tech 0-60 time was 4.4 seconds at this point. Since the install I added a intercooler and intake (gave my K&N/RB Duct away) and the major difference withthese additions is on the top end. Haven't had the opportunity and a sufficently flat straightaway to G-tech since.

Caveat: I have still had my boost set at 10ish psi so all impressions, both before and after the 99 turbos and before and after the intercooler, have been at the same boost level. I had an appointment the other day to go in and tune the car for 12+psi but I hit a f**king curb on the way there and my car is still getting fixed.

Scott

 

I did it because my old twins were dying of old age, leaking oil & coolant but still boosting nicely. My car had about 100k miles on the ORIGINAL twins at this point so I figured I might as well replace them while I was in there - I don't do my own work so labor costs were involved. Had heard bad stories of rebuilds so I didn't want to go that route even though it would have been much cheaper in the short term.

My Tokyo office called Mazda HQ (in Hiroshima?) directly and sourced them for me (The Japanese government is one of my clients so I travel over there sometimes). They actually told us that they wouldn't work on a US spec FD, but I knew otherwise. You can easily get the 99 turbos for almost the same price as new 93-95 turbos from Mazdacomp, Corksport, or any number of places.

Is it worth it? Again, thats a subjective call. If you like the sequential twins you'll really like the 99's... if you want big power you should just go single. No regrets yet on my choice.

Scott

 

Not major power advantages over the 93-95 turbos but they are not hurting either I would have went single if i had the cake when my old ones went out.

 

I have them as well, and they spool alot quicker and hold more boost, compared to the orignal ones. I have mine tuned to 14 psi, but can probably go 1 or 2 psi without doing much damage to the turbos, if its only for short runs. They are expensive and If my car wasn't a daily driver, and I didnt live in CA, I would have just went single, since they are more reliable, give you more power, and get rid of all those worthless vacumelines that like to slip off.

 

I've wondered what the upper limit of these turbos really are. I think the general consensus is that the OEM 93-95 units go way out of their efficiency range at approximately 15-16 psi, generating a sh*tload of heat that even the biggest IC couldn't deal with for more than short bursts. (I think Brooks Weisblat & Pettit were the first to really push this envelope and document it.)

Because the compressor blades are different for 99+ and the abradable seals on the housings are more efficient, I wonder if their upper limit is really higher than the 93-95 turbos? (Assume that adequate fuel is provided - I'm talking about heat.)

Granted I'm not going to run this kind of boost in my street car but I'm still curious nonetheless. I bet some tuners in Japan have already figured this out.

Scott

 

The original OEM turbos start maxing out at 14-14.5 psi, depending who you talk to. I noticed when I had the boost set to 14 psi with my stock turbos you can actually start smelling the turbos burn up alot of oil, which isnt good. When I run 14 psi on the newer turbos, however, they dont smell, and seem to hold the boost quite well. Due to an extra blade design on the 99' sequntials, the turbos run alot more smoother and cooler, so you can take your boost up alittle more, but not much.