Sprintex or Vortech, which setup has more potential?
 

Hey guys,

I've been planning on adding forced induction to my BRZ since before I bought it, and thanks to a very profitable month of August, that plan may come to fruition sooner than anticipated! I have weighed the pros and cons of supercharging vs. turbo and even though I have a brand new Garrett GTX turbo which would pair perfectly with the FA20 powerplant and would save me some money buying a turbo kit, I still prefer the relative simplicity and linear powerband of a supercharger. The biggest thing turning me away from a turbo is the need to replace the exhaust manifold containing the primary catalytic converter. Massachusetts isn't as strict with emissions as California but they're damn close and I don't want to mess with that if it can be avoided. I just feel like a supercharger would be more reliable as I don't have as much to worry about with the oiling system, managing boost pressure, etc.

So supercharger it is, however the turbo has one advantage over the S/C and that is peak power. I've yet to see a supercharger making around 300whp on 93 octane, whereas people are bolting GT28's up to FT86's and making 320whp easily. I'm not saying I need 300whp, but to be able to flirt with that mark somewhere in the future would certainly be nice. I've seen that recently there are 12psi pulleys being developed for both the Vortech and Sprintex/Innovate S/C, but there doesn't appear to be significant data from testing either.

From my research, it seems that a twin screw S/C is superior in design to a centrifugal, but I've seen more peak power coming from those with Vortech kits and not so much with the Sprintex. I guess I'm looking for someone with more experience in FI to point me in the right direction. Which kit do you think has the most potential for power in the long run - the Sprintex/Innovate twin screw supercharger or the Vortech centrifugal supercharger? It seems like both can support significantly higher boost than is currently being run through them, so I shouldn't have to worry about spinning them out of their efficiency range?

I should mention that this is mostly a road car that ought to see limited track use. I have only owned factory turbo/supercharged vehicles before so I have no real-world experience with adding F/I; only what I've read in books and on the interwebz. Also, both the S/C'd cars I've owned were roots-style, so I have no driven a car with a twin-screw or a centrifugal S/C before.

:thanks: in advance!

If you arent looking to replace the header i wouldnt plan on making 300whp on either system unless you switch to e85.

I think FA20club header plus vortech produced some pretty high numbers for vortech and motomike is doing a good job with his innovative.

If north of 300 is truly your goal then you may as well go turbo.

Edit: IF you want more driveabilty get the innovative, they have good torque down low. If you want the max peak HP get the vortech but understand that if either of those are going to flirt with 300 you are going to need extensive exhaust work including headers.

I would say Sprintex for a road car, Vortech for a track car.

I would agree with that, and vortech comes with a intercooler.

Trying to run that larger 12psi pully on the innovative kit we have here currently without IC will be a no go on pump gas.

Innovate will introduce an intercooler that can be added after the fact, or I can import a Cusco/Spritex intercooled kit from Japan (and pray I don't have an issue because no warranty).

If it really will be limited by the stock exhaust manifold I can purchase an FA20club header with high-flow cat and swap back to stock if it won't pass emissions (I have a Perrin 2.5" header-back with high-flow secondary cat already). It's a bit harder to do that with a turbo kit.

Also bear in mind that the chargecooler for the Sprintex kit is a closed system with limited heat capacity. It might be fine for daily driving, drag racing, or even short sprints, but with only three litres of coolant in the system it will eventually hit a runaway condition, dependant on usage/climate.

The vortech is going to have more potential because it's a more efficient compression and can max out higher. The sprintex will give you more of a mid-range bump. If you're looking for about 250-280whp I'd go with the sprintex/innovate. If you want more it will be much easier to do with the vortech.

I think if he ran the 12.5 pully for the vortech then waste gated it to 9psi I think he could hit 300hp, and have the nice torque curve of a base innovate/turbo on pump gas, 92/93

I'm tuned on 92 with the stock vortech pulley, and I'm at 274 with only 20 degrees of timing. (Safe tune)

if i had a gtx28 sitting in my closet i'd say screw the man and do it right the first time. you'll end up wanting more power down the road anyway. it gets boring after a while :).

if you care at all about overhead and absolutely must go s/c, i'd stick with the vortech.

Problem with waste-gating a vortech is that reduces its efficiency.

You are still drawing power from the motor to create 12 psi but only using 9psi of it and bleeding the rest off.

This runs the charger and gearbox harder but doesn't really use it. You can probably see where i am going with this.

It honestly seems like you are more concerned with top end power and the cat. Someone correct me if Im mistaken but im pretty sure you can get a down pipe with a high flow cat in it or put one in the exhaust somewhere it shouldnt be that much of a concern.

Yes, although as I said before I prefer the linear delivery of a roots-style blower. I can have a HFC in both the mid-pipe and right after the header if I opt for the FA20Club header.



Why would I want to limit the Vortech to 9psi?

By running the 12 psi pulley you would hit 9 psi at ~5000 instead of 7500(~ for example).... You would then hold 9psi to redline.

This would also effectively raise the boost in the midrange as well although the factor will not be as apparent in the lower RPM.

@Turbowned
http://www.ft86club.com/forums/showp...&postcount=410