Thread: JBS Twin Scroll Turbo Development

We are currently developing a new turbo application for the 1.8T, there are two stages available which with our hybrid turbo versions will be able to offer up to 550bhp, with full boost predicted between 3000-3500RPM depending on spec.

Key features include:
Twin Scroll Design for better response and spool
New More efficient and larger compressor preventing compressor surge
Better pump gas efficiency
Turbine Nozzle Area (cm2) = Large 10.5 hotside, single flapper.
Improved actuator design

A "twin scroll" or "divided inlet" means that there are two separate volutes within the turbine housing. The main reason for doing this is to isolate the pulses coming from each exhaust port and maintain more of the pulse energy from each cylinder all the way down to the turbine wheel. There are no differences between the turbine wheels used in open or single inlet turbines compared to those used in twin or divided inlet turbines.
Generally speaking, a divided inlet turbine setup will respond faster and produce boost quicker than single or open design of the same nozzle area, of course this is dependent upon proper execution.
While it does not cause any problems or harm to run a divided inlet turbine housing on a manifold that is an "open" design, none of the benefits of the twin inlet will be seen.

With this new turbo set up we will be using our ST316SS SC40 equal length twin scroll manifold for optimum performance.

Here is our twin scroll based equal length manifold.


Again with a twin scroll based turbo.


We have an Audi TT 1.8T 225 booked in for this turbo conversion at the beginning of next week. We will be posting pictures as the kit is being built and of the final product with a full review and RR data.

Then after the Audi TT we have an Ibiza 1.8T booked in for the same conversion again I will post build and final product pictures and RR information.

This turbo set up will also be offered in kit form with fitting instructions and step by step photos for all the 1.8T range.

If you would like anymore information please feel free to give me a call on 01246 455005

Regards
Mike

Latest update on the JBS twin scroll 1.8T turbo applications:

Latest developments show the twin scroll design to be the perfect solution for low spool, high power and factory look turbo applications, as you can see from the pictures below design and production of this highly complex manifold and components are nearly complete.

The pictures show our fabrication department, manifolds on jigs to ensure perfect fitment and location every time.

The final kits will use split downpipe, 3” outlet, 2” dump pipe, 3” inlet pipe
For 225 applications you can use the factory boost outlet pipe, factory engine cover and location.

Further testing has shown 1 bar boost at 2250RPM, 2 bar boost by 3000RPM :D

Manifold, jig and fabrication area.

Further to the update, more pictures:

Turbo and manifold




Me holding the downpipe


Pictures with this kit on the car and in kit format to follow very soon.

Mike

We have fitted this kit to an Audi TT

Here are some comparisons of the BHP per RPM on a few big turbo kits and a hybrid K04.

JBS Twin Scroll with hybrid turbo - Peak 485bhp
RPM - BHP
3000 - 115
3500 - 160
4000 - 205
4500 - 260
5000 - 315
5500 - 370
6000 - 430
6500 - 475

Hybrid IHI - Peak 485bhp
RPM - BHP
3000 - 70
3500 - 120
4000 - 170
4500 - 215
5000 - 265
5500 - 315
6000 - 370
6500 - 405

JBS GT30 Conversion - Peak 430bhp
RPM - BHP
3000 - 95
3500 - 140
4000 - 185
4500 - 240
5000 - 300
5500 - 360
6000 - 400
6500 - 435

225bhp with hybrid K04 - Peak 273bhp
RPM - BHP
3000 - 135
3500 - 185
4000 - 220
4500 - 245
5000 - 260
5500 - 270
6000 - 270
6500 - 255

Here are the RR Graphs

Twin Scroll Hybrid


Hybrid IHI


GT30


Hybrid K04


Hope this helps
Mike

I have a forged engine couple to a GT28RS-71 turbo. This come on full chat (2bar) at just over 4k. Will this turbo you have designed perform that much better? It would be awesome to be on 1bar at 2k and 2bar at 3k!!

Spec of engine is below if you need to know. If this is the case, drop me a price please with fitting as i would be seriously intereasted.

rods and low comp pistons with custom bearing shells, compression lowering head gasket, flowed head with bigger stainless inlet and inconnel exhaust valves and heavy duty valve springs. 4 branch ceramic coated exhaust manifold with GT28RS-71 turbo. Full 2 ¾ " exhaust with Bastuck single back box system. Sports cat. EVOMS V-Flow intake, EVOMS' diverter valve, Sachs racing organic clutch, thermal inlet manifold gasket, B&M Short Shift and full VF Engineering engime mount kit.

Sent you a PM