I know I brought this discussion up several months ago about twin turbo’s & bi-turbo’s vs. a single big *** turbo. I remember the response, everybody even people from other forums got involved spelling out in very certain terms that I don’t know what I’m talking about. And still I walking away from that thread honestly believing that the single turbo is the wrong way to go with the 1.8 4-cylinder engines. The reasons are quite obvious in my mind meaning the bigger you go the more you have to beery your foot into the floor just to spool the sucker up meantime the competition is gone and checked out on your ***! On the alterative, just drive around at 7,000 rpm to keep your monster spooled! I felt if designed right, a new exhaust manifold concept that spits into two to drive two smaller turbos makes a hell of lot more since. Advantages; two smaller turbos would spool-up much faster then one big *** one! Quicker out of the hole hence quicker down the track. Minimum lag time or almost completely eliminated. I hope you can begin to get the picture. Here is something I just stumbled acrossed from Road & Track….
I think it says it all.

09' Fusion will get new 2 turbo 4's and 3.5

"final two engines are the reason for excitement, however. Ford will offer two Twin Force engines, positioned as alternatives to both the four and the six cylinder engines while delivering excellent mileage. The smaller of the duo will deliver between 170-200 horsepower, and in preliminary testing, is approaching a fuel efficiency rating of 30 miles-per-gallon in the city and 40 miles-per-gallon on the highway. And while the final rating will likely be a bit shy of the nice numbers above, the Fusion with this engine will still deliver mileage in the compact-car territory. The displacement of this smaller Twin Force engine has not been revealed yet, but most likely will be a 1.6 or 1.8 liter. The larger of the Twin Force duo will be a version of the 2.5l four cylinder delivering over 260hp, and over 30 miles per gallon highway."

Dont get me wrong,lovebig turbos but I think maybe two twin GT 12's or something just a tad bigger might do the trick better.
It's not how fast you go! But how best you go fast!!!!!

 

You dont have enough space orenough funds to do this. The space is tight and will take over $20k easy to get this done. I dont know what power levels you are looking for, but you can get 500whp with over 400Tq on a turbo that spools in the 3k range and makes 20psi just after 4k and 30psi before 5k and will make power all the way out to 8k+ rpms. Not to mention you can always increase displacement to 2.0 and even 2.2L, increase c/r, and even go stand alone ems that will build boost in nuetral and increase low end timing. All those just mentioned will decrease lag.

How much power you looking for and I can help you from there instead of reinventing the wheel.

 

It would be a waste of money when you can get something that's simple & would produce the same numbers.

 

I don’t think so, first I own my own machine shop, all I have to do is throw a piece of material in my CNC and let-er rip! How much could that cost? You should realize really fast spool at only about 7 to15 psi then multiply the pressure by 2. Compared to a single GT-35 which would take twice thepsi 20 to 25to realize 3/4 the gain in pressure.

 

You cant mulitply pressure with 2 turbos, it doesnt work that way. 12psi form one turbo and 12psi from another turbo is NOT 24psi, its still 12psi!

Again, what kind of HP are you looking for? Until then, your just running your mouth and taking this conversation no where.

 

You're still missing the point. You're now dealing with 2 intakes, 2 turbos, 2 exhaust manifolds, 2 downpipes, etc. Theres really not that much room under the hood to fit everything. Yes, two turbos would be good, look at the S4. Also look at the costs of upgrading components on an S4, with 2 of everything it gets expensive.

I can't tell you its impossible, or not to do it, but really plan everything out, and see if it justifies the cost when you're done.

Or talk to Becca, she has aspirations of twin turbos, and nobody can tell her otherwise, maybe the two of you can team up on the project. I think she's more or less accepted it won't be cheap, but still wants to try to do it.

 

If your runnin(2) 52mm throats vs (1) 72mm throat,,, what do you think will happen.
your total volume increases, its that simple

 

You still dont seem to want help but just talk. Until you post what you want your car for and power levels, im done helping here.

 

This is not about my car,, this post was about twin turboing a 4 banger. As far as my car goes, I've explained that months back! That is still pretty muchthe order of the day for me. Sure its easy to get side tracked along the way only because there are so many options for our motor! But I still think I'm pretty much on track. My car was slated for its $9,000.00 face lift but Istarted having second thoughts if the hp plained was enough. Do I want to push for 375 orplain for450? At this point all plained changes are on hold because of this.

 

Can you do two turbos on a 4cyl, yes. Go see the seq turbo focus. Can you do it on a TT..... no, not without TONS of modification since there is no room for more than one. You want more power sooner, you better of using a g60 supercharger with the turbo.