That could be the case, but I don't think so.



Oooo K...

 

I thought it was mentioned in another thread that the turbos weren't the main factor in producing ~276hp. Granted they are more efficient and they obviously support ~30 more hp stock but i thought it was the flow of the engine that actually gave it the higher output. 13b t/t vs 13b-re vs 13b-rew

 

From what I understand, '99+ you could get either 265hp or 280hp.

Just dug out my Spirit R JDM brochure - shows 255hp and 280hp versions of the car - the 255 being automatics.

Dale

 

The motors are all the same; all year FDs had 13B-REWs.

As for the hp levels, Mazda marketed 4 versions with 3 different power levels from the 13B. Firstly is the standard Type-RB auto and manual versions with 255hp. Next were the manual Type-RBs with 265hp. Then came the Type-R with 280hp, and later the Type-RS also with 280 hp but getting the Bilsteins, the driving lamps, 4.3 Diff, 17" wheels and a few interior bits to boot. There were also limited edition RZs and Spirit Rs as well.

As for the power difference, things like higher boost and the Efini Y-pipe aided in reaching the 265hp mark.

On the top of the line engine (280hp), the motor featured higher flow turbos achieved with the aid of the new turbine blade angles and housing modification. Mazda engineers coated the inner housing with an abradable resin then spun the turbine up to shear away the excess, leaving a seal between the blade and housing in the microns. The result was an increase in flow of 10%. Combine that with a slight increase in boost and better flow characteristics from the Efini series (265hp), and you get the 25 extra horses available when compared to the standard series-7 version engine.

In addition, a thinner wall exhaust system increasing flow area as well as a reduction in rear muffler baffling yielded a 10% decrease in backpressure. Of course this meant that extra cooling was now required, starting with an extra core for the radiator and the re-designed nose which allowed a 110% increase in cooling area plus further 80% gains in oil cooler area. What this basically meant was overheating problems were no longer an issue when pushed hard on the race track.

Dale, thanks for the clarification

~Ramy

 

Hmm, so there is in fact a lot more to the 99 spec front end than just ducting, bumper, lights, and turbos. Interesting.

Dave

 

I had the same question I just put on a set of used turbos and they look just like the set that FDNewbie had posted. I was told that the turbos were 96-98 twins. But what I have read the 99 twins have the gold actuators were the 93-95 had the black ones. I dont know what the 96-98 had. Wll I cant tell if these twins say N3c1 which are the 95 twin or if it says N3G1 the 99 twins.

 

https://www.rx7club.com/showpost.php...62&postcount=2

 

The turbo actuators all start out 'gold'. The plating eventually turns to a greenish color and then black.

Plus, smart sellers spray paint them so the set looks newer.

Dave

 

HDP thanks for the pic, but were was that first stamp HT12 is it on the rear turbo? After looking at those pic Im sure mine are the 96-98 twins