I'll soon be swapping out my '93 OE sequential turbos (115K miles on them) for a set off of a 2002 Spirit R. Any idea what changes I may have to make to the PFC? I'm running M2 medium ic, M2 cf intake, M2 downpipe, Bonez hi-flo cat, RB cat-back. The engine was rebuilt 37K miles ago with 3 mm seals. The PFC was tuned by SR Motorsports, and makes 13 psi. Thanks

 

how much did you get the Spirit R turbos? and from where? i am highly interested in getting them.

thanks

 

Those should be the same as the '99 J-spec twins (280-hp version). I have them on my car brand new from SR Motorsports. My Power FC came tuned from KD Rotary for twin turbos (10/11 psi "low boost"; 12/13 psi "high boost"), street-ported motor, GReddy Type 24 V-spec FMIC, GReddy Airinx, Downpipe, Hi-flow cat, Catback, Nippondenso Comp Fuel Pump, 1300-cc secondary ND injectors. I'm not sure what changes were made for my J-specs--if any? I can tell you that the J-spec twins respond more quickly to throttle inputs than the US spec twins. If you leave your PFC settings as they are for your stock twins, you should be ok.

 

I agree with Manny, my 99 spec turbos (280 hp model) spool about 200 rpms quicker than my stock one. My stock ones only had about 60K on them and weren't abused so they weren't tired and worn out.

Tim

 

Its probably a result of a different manifold design

I wonder if they still have the same carbon seal set up as the old ones.

STEPHEN

 

SR Motorsports sold me new '99 J-spec (280-hp version) for $2650...

 

Jesse Lau soild me brand new zero miles cheaper than that, but I can't say how much

Stephen, not sure about the carbon seals, Bryan might know if he's worked on a set before. The 1st turbo housing is a bit smaller, 51 mm I think, but the blade design for both turbos are supposedly higher flowing than the stock ones. along with the abraidable seals, better effiecieny supposedly.

Basically a better than stock unit, how much, not sure until I tune the PFC Might get Steve to help fine tune my rough to medium tune.

Tim

 

I also got mine from Jesse, a used set purported to have 250 miles on 'em, which I believe is right as they are very clean. Jesse had these posted on his site so no secret as to price - $1900.

 

There's always a better deal to be had I guess. I was satisfied to pay less than Mazdaspeed Motorsports Development's pricing

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Stephen, not sure about the carbon seals, Bryan might know if he's worked on a set before. The 1st turbo housing is a bit smaller, 51 mm I think, but the blade design for both turbos are supposedly higher flowing than the stock ones. along with the abraidable seals, better effiecieny supposedly.

The blades are both 50-mm for J-spec compared with the US-spec 51-mm. The 1-mm shorter blades contribute to faster spool-up time due to the lower rotational inertia of shorter diameter blades. The blade fins have been redesigned to flow MORE air. The abraded "black" seals in the J-spec units result in essentially zero tolerance between the blade's edge and the housing seal. The subtle improvements contribute to the J-spec twins' efficiency in making more boost and faster spool-up time. The J-spec '99 Rx7s were supposed to make 11 psi boost compared with the US spec Rx7 of 10 psi.

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Basically a better than stock unit, how much, not sure until I tune the PFC Might get Steve to help fine tune my rough to medium tune.

My Power FC came tuned from KD Rotary, and I've been into both the "low boost (10/11 psi) and "high" boost setting (12/13 psi). Even at the low boost setting, the boost production is just about instantaneous at revs above 2500 rpm. The boost gauge needle literally leaps from vacuum to 11 psi when you hammer the throttle--same thing with 13 psi. I'm very happy with the setup, and recommend the J-spec (280-hp version) to anyone considering an upgrade to the stock US-spec sequential twins.

 

I agree completely, I love them for the instantaneous boost response.

Been back to the track (FATTs) yet with the new setup?

Tim

 

I recall my old stock sequential turbos providing instant boost to 14 as low as 2500 rpm or even a bit lower. Of course that was with all the bolt-ons and in 5th gear.

That boost response is long gone with my single turbo but better than when I had the non-sequential setup with a set of beat stock turbos.

 

A skilled tuner can manipulate the torque and power curves, within reason.

A map optimized and tuned for the J-Spec turbos will look different than the older turbos. We're talking very small differences that add up to some significant RWHP (5-8% I would guess). But you're going to get about that much with any finely tuned car.

I define a fine tune where not just fuel is adjusted, but ignition is altered to reach performance goals. Just modifying your split my be a start, but not an end.

 

FYI, the abraidable seals on the RS/RZ turbos were designed to keep the contact clearance at zero. That is, when the turbos get hot, the aluminum will expand; which will increase the contact clearance. The abraidable seal will continue to maintain that zero clearance. That is the efficiency gain in the RS/RZ turbos.

Stephen, yes, the RS/RZ turbos still have the "old-tech" carbon seal design. It baffles me that Hitachi hasn't come up with anything more up-to-date for this application. Dynamic seals last so much longer for turbos .... and they don't suffer from the same heat problems. Maybe on the 4th gen ....

I'm looking forward to getting my car dyno-tuned with the RS/RZ's .... but first, I have to get off my lazy butt and finish putting in the clutch/flywheel and the 'new' SMIC.