"The series arrangement, the more common arrangement of twinchargers, is set up such that one compressor's (turbo or supercharger) output feeds the inlet of another. A sequentially-organized Roots type supercharger is connected to a medium- to large-sized turbocharger. The supercharger provides near-instant manifold pressure (eliminating turbo lag, which would otherwise result when the turbocharger is not up to its operating speed). Once the turbocharger has reached operating speed, the supercharger can either continue compounding the pressurized air to the turbocharger inlet (yielding elevated intake pressures), or it can be bypassed and/or mechanically decoupled from the drivetrain via an electromagnetic clutch and bypass valve (increasing efficiency of the induction system).

Found that on the internet ^

Don't take my word for it.

 

It must be true... they can't put anything on the internet that isn't true!

You would still be much better off (and probably cheaper) to just to a BAT VR6 swap...

 

I think you guys are talking about two different things. The bypass valve redline is talking about is synonymous with diverter valve or blow-off valve. Kamil seems to be talking about some kind of intake bypass valve that diverts the intake charge between the blower and the turbo depending on engine conditions. I believe BMW uses this kind of setup on their twin-turbo engines.

 

BMW isn't the only company doing it. Pratt and Whitney, Lycoming and Rolls Royce did it on their aircraft engines during WWII.

 

So after reading more and more I realized the best route for me to take would be finding a wrecked S4 or A6 so I can acquire an entire 2.7t motor with the 10E tranny preferably, but I can live with the 10A.

Redline has stated the 2.7t internals are better to start off with if we plan on building the entire motor. Even though the 2.7 internals are better, he has also stated that a lot of guys out there use 2.8 heads because they have slightly bigger intake ports.

My original idea was VR6 or twincharging the 2.8. The train of thought has changed and I think it would make more sense to attempt to twincharge the 2.7t...

Being that I already have a 2.8, I will just wait it out till I acquire the proper donor car and etc.

I am still wondering though. If I strap the 2.8 heads onto the 2.7t block, will I be able to mount the PES G2 Supercharger (also known as the Eaton M62)?

From what I have already read, it appears it would be possible to use those 2.7 internals and mount the supercharger on top.

The next step for me is deciding which is better, single or twin turbo? I realize the 2.7t was designed for two turbos but I think it would be easier to run one turbo off two exhaust banks because you would only have to worry about cooling one turbo instead of two.

I think this project would be better for me because I wouldn't have to worry about finding custom parts of fabricating custom parts. I imagine the project will be expensive regardless but I think it will be cheaper than a VR6 or 4.2 40v swap.

 

2.7 internals would be counterproductive. why strip one block to put the inernals in another block that is the exact same? not to mention you cant use 2.7 pistons in a 2.8 block.

as far as i know, the pes supercharger will bolt right up to a 2.7.

with that said, i have a hard time believing youll alot the resources to pull this off. IF you find a 2.7 and IF you successfully tansplant that in your a4, just do this you can do it to your 2.8, but it would be better on the 2.7 internals.

and keep in mind, many parts you need to turbo the 2.8 will come off the 2.7. intake and exhaust manifolds, ecu, harness... you might as well just start with a 2.7. they can be had for less than $1000, which would make it cost beneficial seeing as how you;d have that much in upgrade parts for the 2.8 alone

 

Well if you can strap the G2 right up then its possible to twin charge the 2.7t. I thought it would make more sense to find a donor car than to find a short block or an entire used engine.