my 10ae has 2.5" exhaust, 3" intake, twinscroll working, really good condition turbo, full boost by 3100, starts to pull at 2650. similar probs as you, i have to port the wastegate to get rid of the boost creep, if this is not enough, rev the motor more! 4500rpm launches give you all the torque you need

 

This is just a note; I posted a few days ago (top of the page), saying that the boost response with N/A rotors wasn't anything special, but now that I think about it more, I'm somewhat convinced my twin-scroll is open all the time...

When you guys talk about building boost 'early' (i.e. nubian: full boost at 3100), is this in 1st gear?

I'm probably hitting 5psi in 1st at 4k RPM's.

BUT, in 2nd I'm at 8psi by 4k RPM's.

3rd, I'm at 11psi by 4k RPM's.

Can anyone post there boost patterns by gear?

 

Are the S5 upper and lower intake manifolds worth upgrading to?
Would it make sense to get a smallish housing, with a high flow trim on the hot side, and a small compressor? I'm thinking I'd get a good VE with 8-9 psi on the stock intercooler.
For torque...do I want back pressure at low rpm, or are rotaries different?

Thanks for all the input so far! It's great having a pool of info on how other Rexes are spooling up!

 

Eh, rotarys can have some torque. I have a dyno sheet of my s4 tII making 217 ft/lb torque at about 3700 rpm. I hit full boost that run before 3000 rpm. In that run i made 206 hp at 5500 rpm. Thats breaking the mold for a rotary as far as im concerned. This is an s4 tII engine with s5 turbo, no boost control. about 11 lbs boost. With the s4 turbo (with twin scroll still on ) i only made 176 ft/lb of torque and 194 hp. so, basically, s5 turbo is definately worth it if you can get it. Verrry responsive compared to s4. Hope that helped.

 

For the short while that I had my stock turbo on the car, all I can say is wow. I have never experienced such quick of spool except on those 1.8t's and dsms with those tiny tim turbo's. I say I hit the 5lbs before 3krpm. It was instant boost(this is on an s5turbo/man.) I do miss the quick spool of the stock turbo.

 

Can a s4 be upgraded with s5 components to get faster spool? Or is it not worth it, too expensive, too bothersome?

 

Yes, the S5 turbo and manifold is a worthwhile upgrade. Cost depends on luck...

 

if you r gonna put an s5 turbo in there... you might as well go hybrid. yes i was talkin 1st gear... come to think of it, yes it does change every gear, i was refering to the pull though.. 1 and 2 gears are about the same, then i get medium boost creep in 3. 4-5 are dumb right now, because i can barely break 4rpm. really need to finish upgrades before i push my luck

 

Ok lets see, s5turbo/man $150-200, hybrid $400+...

 

$400 plus ain't so bad though. What I would really like to know is if it will be better all around, i.e. spool quick down low with some potential up top as well.

 

sorry my mistake, bnr upgrades start at $650