Not necessarily..depends on the collector size and length.If you don´t use a common collector,then the 2-1 collectors should be the appropriate size,to minimize pulses and backpressure.I´m not saying that is the case with your system,just speaking out generally.I´can´t remember where,but I saw a collector that someone made from a Burns collector,it was a 4-1 system with a 4-1 collector that then divided into 2 rectangular pipes to the twin scroll flange.As far as heat retention and minimizing back pressure,I think that would be pretty effective.

Ah, yes, that would work too, but it does mean you are keeping all 4 primaries seperate untill at the divided turbine flange and only then merge 2 into 1, twice. Its still a twin scroll header then, only you keep 4 primaries all the way untill the turbine, resulting in much longer primary lengths, thus reducing spool time imo.
My turbo location is already rather far away, so I will do anything fysically possible to keep pipe lengths to a minimum, hence this construction/lay-out ;)

Yeah,I hear ya Wally - space is a big problem.I´m hoping my GT3071R will fit in your old location.I won´t find out until I have the engine in the car.Hopefully my case will finally be back on friday so I can put it together.I will be putting the car together this winter -finally.

Winter time is the best for car projects!

Yeah,finding time and motivation can be tough.Thanks to threads like this it keeps the fire going.So if my car never gets finished it´s Wally´s fault for not posting enough videos and pics :lmao:

Wally we need more videos, pictures, everything you have to keep us going!!!!!!!!!!!

Haha! well, not spectaculair news, but some small steps are sometimes needed as well to complete a job.
So, I now finally have the oil feed for the Borg turbo complete :)
This was quite a hassle. Why? see for yourself:

http://i174.photobucket.com/albums/w...1.jpg~original

http://i174.photobucket.com/albums/w...2.jpg~original

Left to right: 1/4" NPT is the thread size into the turbo, so I needed a 1/4" NPT to 1/8"NPT adapter, 1/8"NPT male to 1/8"NPT with 0.165" restrictor (1.5mm), 1/8"NPT to inverted flare female connection and M10x1.0 inner thread, M10x1.0 male and inverted flare 'copper' 5mm (~3/16") brake line.
This connects then to a goodyear braided oil line (with M10x1.0 ends) that feeds of the oil pressure connection on the engine case (with a 'T' for a oil pressure sensor)

Next job will be the oil drainage adapter, which will have to be made from scratch (from hi-grade alu) for my -12 line... (all adapters for sale are -10...)

Why the 1.5mm restrictor?

Folder! This is almost like a masters class.

1.5mm or AN3 line feed.
Its prescription from Airwerks Borg-Warner. Same as large frame Garrett non-ball bearing turbo's ;)

Learn something new everyday! So this one isn´t ball bearing either?

Nope, no ball-bearing. Would have loved to have that in there as well though, but these models just don't come with them.
The twin-scroll should provide the quicker spooling. When tuned right (header sizes), these spool as 'fast' as a Garrett 35R does with a little more hp under the curve, but for less then 2/3 the Garrett BB price tag ;)

If you have the same spooling time as with the old turbo but more power and ability to keep the boost level in the high rpm aswell, then it was worth it imo.The BB turbos are nice,but like you said so much more expensive.You would have to ask yourself if the advantages of the BB outweigh the price tag.

This turbo is NOT a logical 'upgrade' for this engine!
I am sure spool is much later now, as this is a TOO large of a turbo for this engine/application. A comparable BB turbo of this size would also have later spool, but like I said before: this turbo was NOT ment for this engine, but a much larger one ;)
Still I am very curieus what this will do on this 2.2 engine as I have so much data on this engine already.

Only if you look at a drag racing application, this turbo could do well if the cam could support the flow/rpm. For pure drag racing, the cam is not optimal either though..

As always, its a big compromise as it is.
It is tempting to completely disassemble the engine and do a cam swap, just to give it drag racing caracteristics and really let it rip at the strip :rolleyes:
Not for now anyways, I have a hard time thinking how to install this turbo as it is ;)

When is enough?
 

:(
Hi Walter, I have noted your up-grades and congrats. Question, when is enough on your current engine, before you have a major failure? You have done very well, I'd hate to see you engine let loose:(.