Completely random thought (was reading autoblog and they had a rumor the new boxster would sport a 2.5 liter flat four that would be TT'd) but is it possible to TT a subaru? What is the upside? (I'm assuming faster spool and more top end). Is there even enough space? Has it been done before? What are the drawbacks to a TT? Always been mildly curious as to why I've never seen a TT build done on a WRX.
Old school legacy's were twin turbo and you can pick up the motorcar for around 1k but it's not up to part with today's wrx setups. There's also a few builds including kits floating around. Here's one.
^^ That is misleading. Twin-Scroll (TS) is not the same thing as a twin-turbo (TT). Twin turbos have two turbochargers that can be set up a couple of different ways. The one in the WRX above is a parallel TT set up where each turbo is the same size. Because of all of the extra plumbing necessary (each turbo needs its own air intake and exhaust connection) this set up lends itself to motors that have symmetry (V and H style engine configurations). Because you only have half of the exhaust gas flow through each turbocharger, the turbos themselves are smaller in size. In general the pros of a parallel twin turbo set up are a fast spool time with respectable top end power. However, set ups with a single larger turbo will almost always have more top end power but substantially more turbo lag. The new BMW M5 uses a TT V8: The more cylinders you have, the more exhaust gasses you have. The Bugatti Veyron has 16 cylinders and 4 turbochargers. The other TT design is sequential turbos. This layout uses two different sized turbos (one small and one large). The small one spools quickly to reduce turbo lag while the big one spools later but provides plenty of top end power. Though these setups can be used on any engine conifguration, the sequential TT is a favorite of I-6 engines (Supras, and the BMW N54 engine). Here is a sequential set up for a Supra: A twin-scroll setup uses only a single turbocharger, but has a completely different plumbing set-up on the exhaust manifold. A TS turbo has two exhaust connections where a standard turbo only has one. Because you split the exhaust system into two manifolds, the size of the manifold is reduced. With the reduced size, the exhaust gas velocities are higher. In Subarus, the unequal length headers (where we get the boxer rumble) are replaced with equal length headers. This smooths out the exhaust gas pulses and coupled with the higher gas velocities means a faster spool time while maintaining good top end power with a single turbo. Most JDM STis are running a twin scroll, as well as the newer BMW N55 engine. So to put this in perspective of a WRX, a twin turbo set up does not really make sense because it would require extensive fabrication, and because you would only have 2 cylinders per turbo the turbos would have to be very small. The money would be much better spent going to a single twin-scroll setup (like the one pictured above).
Here is the list of Subaru engines that are twin turbo from the factory. Like its been said, they only Subarus that came twin turbo were some of the older Legacys (JDM only) -EJ20H JDM 93-98 Legacy -EJ20R JDM 96-98 Legacy -EJ206 JDM 98-03 Legacy -EJ208 JDM 98-03 Legacy I have the EJ20R in my car, but it had to be converted to single turbo. The stock twin setup wouldn't fit because the brake/steering stuff (since its a left hand drive car compared to JDM right hand drive). There was an Impreza (older one) here in Atlanta that installed the EJ20R with the twin setup, however I'm not sure how they did it.
Misleading depending on what sort of answer you were expecting from him. And he says "running one", get it?
Twinscroll simple DOES NOT work well on a Subaru. Been tested and proven time and time again. Now twin turbo is few and hard to find on a Subaru. That blue bugeye above was running well but it wasn't that impressive......GT35R was spooling faster and maybe not quite as high but the powerband was much longer and better. Here's that TT car's graph. On a similar built engine GT35R car....I bet it's close if not better not to mention a heck of a lot cheaper.
screw your twin twin-scroll turbo setup bullshit, how about 3000HP V-12 powered Belair http://www.youtube.com/watch?v=SIj2GVfua84
Cool, why so butt hurt? In none of my previous comments have I attacked any one person, well John but I don't no how to spell bananana. Why the hate? Where's ScoobyMike when you need a mod to clean up a thread?
ill see your v12 and raise you a bagger 288, if you get in its way you're soon to be de-meated.. http://www.youtube.com/watch?v=azEvfD4C6ow