Porting , or boost ? 350 goal better powerband ?
 

yeah I guess the tittle is a bit misleading


I'm just curious about the idea . and Would like to ask what your opinions were on the subject .


there are a few ways to make power out of a rotary we all know that .

But what about maintaining a wide powerband .



now my question is this. which will yield a better power band result .

Say Option 1 stock ports to maintain low end power , and a bigger turbo that will achieve your desired goals , say 350 or 400


Options 2 , use a smaller turbo then in option 1 for quicker spool , BUT port the engine for more power top end .

Which would yield better results what would be the differences in the characteristics of the motor using these 2 options ?

As I understand it, enlarging the ports shifts the powerband to the right in exchange for a higher peak horsepower at the highest rpms. The larger the port, the more dramatic the change.

Personally, I would stick with stock sized ports and a gt35 sized turbo. If 350whp is your goal than you'll EASILY get there with a small/medium sized turbo.

Also, you left out the option with stock/smoothed ports, a small/medium BILLET turbo, and higher boost levels ;)

Porting is a good way for N/A rotaries to flow more air, thus making more power.. FDs have the "easy" button, being the turbo, where you just gotta increase the boost to bump up the air flow.

Stock FD ports will flow 600whp+ for sure..

at the end of the day, whether ported or not, the key is sizing the appropriate turbo for your application. for 350, i wouldn't (in good conscience) tell you anything more that get an appropriate turbo for the car and whatever supporting parts you'd need to make it work safely. porting really isn't necessary at all for that power when turbocharging is involved.

quite true, but i just want to add though, that from what i've seen it's not really a common occurrence - even for the people making 600+.

Agreed, however it also begs the question of whether "common practice" equated to "necessary practice" in this situation.

This scenario is, I believe, well beyond the scope of the original question. However I think that if the tuning is right, and the supporting mods are right, than "big" power on stock ports should totally be doable!!

ok now lets throw a bit of a twist ,

My motor is currently ported medium street port . I drove it around a bit and I did feel a lack of low end power .

Now if I had Gone the single turbo route

gotten a larger GT35 single with stock ports

VS using the 99 twins sequentially at 330 WHP

which would have a wider power band I'm not looking for much power just reliable power with a wider torque band .

without actually searching for graphs on either (that's on you :)), if i had to guess, i would probably say the twins are probably going give you a better torque curve in that things will probably happen sooner and stay live for the usable stock RPM range. higher RPM use would likely bring more intake heat though.

depending on which turbine housing you go with on the GT35(R), you could probably come close, if not match, the initial spool of the twins, but i doubt you'd match their overall linearity. that said, i don't think it would be anything a good, sensible downshift couldn't fix if you needed it. also, i would expect the GT35 to ramp up softer, but plateau higher than the twins ... and still be on the boil in the higher RPM.

my 2 cents.

Thanks , to everyone , alot of great info we'll see how things go , My friend has a quick spooling turbo , and I have the twins we'll see how our torque curve compares in a month or so .

his motor is ported though .


Also , as far as heating up the intake air temps .. I'm ok in that aspect atleast