After being disappointed with BNR sequential #'s I'm thinking of going single instead.

These are what I'm looking at in order:
GT35r
GT40r
T04r

I'm planning on it being a weekend street car that's used a lot on twisty roads but also on open highways.

I'd like to hit 400rwhp. But 450+ rwhp sounds great too
I've heard I won't really need more than 350rwhp or so for my uses...
And of course knowing I was considering the BNR's, you guessed I'd like a quick spool time.

Your thoughts?

 

35r with a 1.06 divided t4 turbine. I have the exact same goals as you and that's what I did. Research some compressor maps and dyno plots.

 

The GT35R has proved it's performance!!! What a great turbo!!!

 

How did the BNRs do?

Keep in mind that to 'go single' properly, you're looking at 4 to 6 grand.

 

gt40r and 35 lbs of boost

 

I would go with the 35R with a 1.00 A/R. I had one on my 2 rotor. I never had any complaints about the top end and would have preferred a little faster response on the bottom end, so I think going any bigger would be a mistake on a street car. The engine has so little power off boost I think you should get a turbo with a broad powerband.

 

35R divided T4 either 1.0 or 1.06 is the best all around fun street turbo. The GT3574 is a close second but doesn't quite have the transient response of the 35R.


~S~

 

^
The turbo god has spoken!

 

the gt35r would be a good choice but i would go with the .82 and not the 1.0 or 1.06 if it is for street use.

 

Not if he is looking for 400's at reasonable boost levels and pump gas, The .82 is usually in 330-380whp range and does tend to drop off up top.

1.0's are nice as they tend to really come on in the 3300rpm range and not drop off up top. 1.06's aren't off that by much, close enough that differences in setup could make one better than the other. The 1.06 does tend to drop a few more RPM's on shifts though.

He needs to figure does he want the mid/upper 300's or low/mid 400's

 

Low 400's would be ideal. I'm leaning towards the 35r more and more it seems.
Also what of the 500R?

FYI CA only gets 91 @ the pump.

 

Stock ports? If so run the 1.0 divided 35RT4 no larger. That or look into the 3574 .84 A/r both will be vary similar in performance. The last 3574 setup we did here on a stock port motor with a knockoff small SMIC did 386whp@12/13psi didn't feel laggy almost felt like a 35R car. The difference is with the 35R on a roll it will snap to positive pressure sooner, due to the BB CHRA. It's a hard choice between the two. I tend to favor the BB units for their transient response.


~S~

 

You should also consider the T04Z which is the ball bearing T04R. Its has good response and will easily make the HP you're looking for.

Fact is there are many turbos that will give you good response and HP.

 

When I get all this done I'm having a streetport done aswell.

So it seems with the uses I plan on having for the car and the goal of low 400's (rwhp), a GT35r is my best bet.

 

About a year ago someone dynoed 412 RWHP sequential. There have been many dyno over 420 RWHP non sequential.

One thing you have to remember, for a Rotary to run right for 350 Plus RWHP, everything in the car must be about perfect to stay together. I would say a small percentagle of RX7's out there run 15 psi or more. The rest either are broken or mildly modified. When you get over 400 RWHP the boost has to be cranked up and it has to be tuned just right...


Bryan@BNR