I have noticed that all of the turbo upgrade systems that I have found for the Evo are single turbo upgrades. From my understanding, from a driveability standpoint, it is not a good idea to put a large turbo on a small four-banger. In my limited mental capacity I would think a twin-turbo system would be better than a single. From my meager understanding I believe that in a twin-turbo system there is usually a smaller turbo which spools at lower RPMs to help a larger turbo to reach full boost in a smoother and quicker fashion. So where are the double systems? Conversely, and off-topic, why are pretty much all of the 350Z turbo systems twins (I did find one single turbo kit)? I hope there's no obvious answer that makes me seem to be a maron.

 

350Z's are twins because it's a V6--two banks of cylinders, two turbos.

Don't know if there's enough displacement in an Evo to run a twin turbo set-up.

 

OK...here we go. To keep it relatively simple, the major reason there are no tiwn kits for the evo is under-hood space. Also, if there were to be such a kit, the turbos would be pretty damn small and wouldnt be nearly as efficient as just one turbo. And about the 350z turbo set up, most of the kits are in twin setup due to simplicity because of the fact that the engine is in a V format as compared to the 2jz of a supra which is in a inline set-up. Basically, a twin setup is pretty much unheard of with us 4-bangers. Hope this helped out

 

Ok, let me add to the ignorance... The twin turbo systems on the Supra's and RX'7 are secuential, with a small turbo spooling at lower RPMs and a larger one at high RPMs. I think that's the setup you are talking about. As for the 350Z , it is just like my VR4, been V format it is easier to put one turbo on each side of the V. Now, talking about the 3000GT VR4 , the one I really now cause it is the one I have, I can tell you that we (and now talking about the 3000GT comunitty) install big turbos in our cars, as big as 20G and maybe larger(for some few thrill seackers) but larger than that you start having problem with lag.

Now my mechanic is thinking about installing a twin turbo setup to his MR2 , he was thinking about the advantage of faster spool of the small turbines. While a big turbo is tougher to get to full boost, a small turbo car reach that limit faster, but then again the limit by the size of your turbos.

Smaller turbos are better for faster spool like road race, Rally type races, bigger turbos are more suited for drag race and top speed test.

Just my opinion...

Later,

 

i agree with everyone so far, displacement size is a major factor, if the engine can spin a single turbo better use it, a small 4 cyl, a normal everyday driver, cant run two turbos, it will not beable to produce enought exhaust gases to spin two fast enough to make the same boost pressure as the single kit, v style engines can do so because they use 3 cyl to run a slightly smaller turbo. just look at the vr's of the past. in short to have a twin turbo i-4, it would have to push serious exhaust gases and have tons of room for the two turbos plus piping.

 

Don't forget the complexity of all the extra plumbing required to have two turbos. You'll need an extra set of oil feed and return lines, coolant lines, o2 housings, a y-downpipe, and header. If you want a sequential setup, you'll also need some type of switch valve and something to actuate it.

Then you'll need to select two turbos. Since there are no proven setups out there, you're going to need to experiment w/ different size turbos until you find something that works. Are you willing to foot the bill for all the fabrication and R&D? You're gonna need some deep pockets to get this thing to all work well. At this point, a turbo kit for $4k would sound like a bargain to me.

 

110% agreed with the above

 

4 bangers = no twin

 

A little correction if i may. Not all twin-turbo set-ups are with two different sized turbos and not all are in sequential form. For example, yes a MKIV Turbo Supra is a twin turbo and yes its in a sequential setup, but both turbos are the exact same size (CT-10). All a sequential system is, using the supra for example sake, at idle to ~3,500 rpm only one of the 2 turbos is operating, then from ~3500 to ~3,750 the second prespools, and then and only then from ~4,000 rpm both turbos are fully online and functioning.

The other way a twin setup can be configued is known as a True Twin setup, which basically means both turbos are online and function all the time. This, my friends, is how all the 350z twin turbos systems operate. Think about, if these systems where sequential, then that means that at the time that only one turbo is spooling then an entire bank of cylinders is not being used, cuz as we all know, a twin turbo setup on a V-engine means there is one turbo on each bank of cylinders.

Single turbo systems on VR4's, 350z's, and others that have some sort of V configuration, can be done and have been done, but they require more fabrication for the exhaust manifolds. This is why most of the kits out there for these cars are in a twin setup. Also this is why a single turbo conversion is so popular with all the supra fans.

BTW- From what i've heard, there isnt any aftermarket twin setups that operate in sequential form.

 

displacement? the 3gen rx7 has 1.3 liters. there's just isn't any room in the evo.

 

Yeah, but that's static displacement; the thermal efficiency of a Wankel and the power pulses equal roughly that of a 3 liter Otto cycle engine. Not exactly an apples to apples comparison.

 

Did you guys read the motor trend a couple of months ago. the 10,000 hp shootout. it was with the vinshu evo and alot of other big hp # cars. there was alot of twin turbo vipers and vettes and only one beat the vinshu evo in the quarter mile. some of the cars had like 800hp TT motors (vinshu evo had like 450hp) and the evo still smoked them. so we dont need twin turbos, other cars need it to keep up with us. :-)

 

the only relevant way i could see twin turbo on an evo is if the motor was 4.0L! then you would have displacement to run essentially 2 16G's however i don't think it would be very efficient. i'm also really surprised that the aftermarket didn't pick up on the porsche 968 (3.0L 4cyl) as that motor had room for improvement. imagine if we could squeeze 3.0L out of a 4G63 with a big fat turbo...

 

well here is a twin turbo s2000

 

Just throw one of these puppies on your Evo and be done with it.

http://www.angelfire.com/pop/bbvc/supercharger.html

http://www.rippmods.com/products/pro...id=3&vehcId=17