emwporsche

that twin turbo dyno graph read: lag, wheelspin, shift
I would have taken the lower hp twin charged system
good read though

gt37vgt

its impressive perhaps going for a bigger turbo in the compound set up would give it a bit more top end .
the compound system has 3 more squares under the torque graph .. wich realy i don't think is enough to justify the complexity and expense .
much like my VGT set up its differentially a DIY thing .
I think the best thing available these days at resonable cost and dram factor is one of those butterfly things you bolt to the inlet of a twin scroll turbo .
you get most of the VGT effect and you have much more turbo and fuel choice .. given a clean slate i would be going that way

blown 944

This is a better setup

333pg333

Interesting how they say that with E85 you require 40-50% more fuel? I wonder if this a generic comment or one based on this sort of high hp project?

gt37vgt

generically its about 28% more fuel needed to make the same HP based on the calorific values ..
but its kind of assumed in a turbo application your gonna up the boost so they factor this in and say 40 to 50% more fuel

blown 944

I don't thing they really calculated it out, just said it generically. However they were running at 62 PSI manifold pressure!!!! so who knows.

edit; sorry 44 MAP on this project

I am more intrigued by the flatter TQ curve

Voith

what for? is boxter abs better than 944 abs?

eniac

So far on E85, I have not had to turn my fuel up more then 22%. Granted I was intentionally slightly rich on non-E85 fuel but saying 45-50% seems almost double my real world actual results.

Visionary

Why not just use a self-contained variable-vane turbo that's actually sized for your application? Aerocharger technology

Though variable-vanes do aid in spool up immensely, you can't expect to be completely blown away by the 997's turbos. The bearing design and lubrication system of the Borg Warner variable turbos is no different than that of any conventional turbo. The bearings are still lubricated with hot engine oil and the bearings are flooded. Water cooling helps but the amount of drag on the bearings is the same. Drag/friction on the rotating assembly of a turbo does not help spool up.

The Aerocharger is a completely different design. The entire bearing assembly is mounted in front of the compressor housing, in the lowest temperature section of the turbo (see diagrams in the link above). They are ball bearing and instead of the bearings being lubricated through the engine they have their own oil reservoir where oil is misted onto the bearings via two wicks. This coupled with the fact that the oil is specifically formulated for high speed bearings instead of just designed for your engine. Low mass wheels, low drag bearings, high speed oil, generally lower temperatures, AND variable-vanes = a truly lag-free turbo.

Heat is another issue. These turbos control heat better than most conventional turbos. In between the compressor and turbine housings is a specially designed heat shield. There are also form fitting turbine heat shields which sandwich between your turbine outlet and down pipe and wrap around the entire housing. Typically a double layer of header wrap is installed between the turbine housing and heat shield to further control heat.

boerge

WHere is Blown44? I would love to see him play around with the aerocharger..

TRP951

The aerochargers are cool. I thought they closed down but aparantly not. The only concerns about putting one on a 951 is theres nowhere to mount on the center section and the steep price for one. They also dont have very large turbos IIRC the largest one they have only flows like 36-37lb/min

blown 944

The idea is sound IMO, if the bearings and turbine shaft can handle the lateral load.

It is truly a DBB_ VVT turbo all in one.

Cost would probably be an issue initially.

Mounting would be dealt with differently anyway, as you may need two of them as to not overrun the shaft speed.

PorscheDoc

Not on a 951, but at least it is a porsche

Buddies at aerocharger brought out their new toy to the track this last weekend. Looks like a pretty slick setup, really impressed with the technology.

Silver Rose

We should mention it was fast. The fellow was a decent driver and the car had plenty on the straights!!!

The copper coils you see under the turbo exhaust are hookup tubes for data collection.

They were talking about full boost at roughly 1000 rpm sooner, regardless it was a really nice setup!!!

PorscheDoc

Yea, if you have driven a stock 930, you know they are laggy as hell and quite honestly not that fun to drive because of it. They said it really made it into a nice driver with quick spool. (They also had a bad **** pit...errr mobile. Should have taken pictures of that, lol)