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[Giulietta24vTT]

I have removed the twin turbos to clear some room for the AC on my engine and on the way fabricated a new manifold that uses the existing TT 3:1 manifolds for a single turbcharger .
It is still too early to say how efficient this system will be and wheather it will defeat the ideal TT setup on the V6 , however I have very good experience with single Turbo conversions on 6 cylinder engines and I am very excited:)
The great advantage on this specific setup is the use of a split inlet turbine housing that will separate the exhaust pulses of each of the 3 cylinders pairs and hopefully will improve the spool up time.

I'll have it coated with ceramic thermal coat and some isolating fiber wrap later on this week.
I did not manage to get an under-car connection pipe between the manifolds because of the massive exhaust downpipe+external wastegate's pipe on the same side.I'm also preparing a new bonnet and Intercooling system to face this new setup.
More pictures soon when I get it all welded tightly and coated.
Cheers
Chen.

[Barry]

Chen,Watch this space.......Im busy with a single Turbo 3.ol 24v for my Giulietta...

Say Hello to Moty,ok??

[Mats]

This one goes up on the "crazy-wall"

Keep smoking that crack...
Ok, seriously, that is going to be one crazy car. Twin entry truck turbo? Try to separate the sides if possible so that pulses doesn't "leak" to the other side when the wastegate is closed. But I guess I don't have to tell you that.

[Barry]

Im afraid mine is not going to be that elaborate....Just a log type manifold on the left head,x over pipe from the right head under the sump..

Its still going to a killer..My 2.8l 12v turbo`s made 240 wheel hp at .7 bar..
Im expecting some good stuff here...

[Barry]

Basically modifeid my 12v manifold for the multivalve...

[Giulietta24vTT]

Well,
Today I've finished the new intercooler plus air pipes and welding the manifold and wastegate flange:)
Tomorrow will try to build a 3.25" downpipe and a separate wastgate pipe that I will dump outside to free air .

Cheers Barry , that looks like a huge 1,35 A/R T4 turbine housing on your picture, I can't wait to see how my new toy will spool on the 3.3 grandpa

[Giulietta24vTT]

Almost done,funny thing is I can now fit the AC compressor on the other side:)

[SydneyJules]

Jeez you two. this is basically demoralising to every body else on the board....

Baz- got any pics of the X over pipe?

Chen, HOWTHAFARK do you drive that thing around with a straight cut? I still dont understand it...Nice to see you have (or did have!?) A/C on it too...

Wet dreams.... these photos make it so hard to concentrate on study!

[twinspark6]

why not go with a 3" downpipe? Even a 2.5" works well.

[Barry]

Jules,Not yet..I will make it from 316 stainless with a slip joint at the sump.Basically it comes up beneath the turbine housing from underneath.

Chen,This is actually a .82 single inlet Garrett..housing..Im not even sure what Ill be using at this stage.
Probably a .6 housing opened up for a to4 dash 5 Turbonetics shaft..Ilove the Turbonetics stuff,very light...Same combo I ran on the Lancia Intergrale..
My setup will not be for ultimate top end power..I cannot stand something that only starts boosting at 4000rpm and then suddenly makes 500hp..
I prefer boost coming in very low,like at 2500rpm and full at 3000rpm.Id glady sacrafice 150 hp for the drivability of the setup.

Im afraid that everytime I build a 3.8 for my car someone comes along and buys it from me..I dont know what it is with people,but they always think because you built it for yourself,they`ll be getting something special..
Ive already had someone phone me for the turbo 24v...but,no..this is mine ...

[Barry]

Chen,If I may criticize here...Move your wastegate setup to the turbine inlet...At the moment gas has to change direction everytime the wastegate opens ....

You going to slipjoint or bellows the x over pipe??

[Giulietta24vTT]

Thanks Barry,good point, I was trying to cut a twin entrance wastegate flange to position on the inlet ex side but was afraid it would ruin the whole separate inlet idea (as the WG's door itself is 10mm from the flange and gas could go from side to side even when closed.
No flexy or slipjoits on this one, the smaller flange is horizontal so that the X pipe and turbo flanges can be easily lifted up, bonnet will take some extra 6cm (S70 volvo style) cut n lift.
You're right the stg5 shaft is great , goes very good with the T4 60-1 compressors as far as balance and ,drivability and high outputs concerns ,the new turbo's shaft isn't that larger,it's a 74-68mm turbine wheel and 88-62mm compressor wheel with unkwown A/R(measures something like /96 on turbine)
My ex twin turbos were probably heavier together , I assume this truck thingy will give at leaast extra 500 rpm spool.
what do you think is the right downpipe's qidth I sould go with(limited to 3.7" by the starter motor)???

Twinspark6, the higher the output the bigger the exhaust needed to clear out the gas mass:), 450+bhp (even 300+) engines , even diesel engines, use 3.5-4.0 Inch pipes from turbos out.
I used to have 3" pipe after the twin 2.5" downpipes and my engine could not rev beyond 6000rpm ...the problem was soled with 2X2.5" pipes all the way back. 3.5-3.25" almost equalls to 2X2.5" , that's the general idea...

P.S Barry ,
Any pictures of the Integrale is it rare in SA?(we currently have only 2 Evo's here)

[Barry]

Ok,I understand your problem--what I would do now is take another pipe from the x over directly to the inlet of the wastegate...this will prevent the gas from changing direction.......
Ok,im thinking about this-its also stuffs up your exhaust pulse design for the twin scroll entry....scrap the idea....

As for down pipe,I run 76mm from turbine for about 26 inches and then gradually bring it back down to 65mm.This has always worked on my 300 hp engines..

[Giulietta24vTT]

B,
Maybe I should restrain myself with the downpipe ,85+ is becoming virtually dangerous for the harness and starter motor.I can go with 4" from turb+90 bend vertically and then use a 304 cone to reduce into 3"

Rethinking bout' the wastegate design I hope I won't be encountering "Boost -Creep" situ' when the WG won't be able to lower the turbo speed, maybe I should put another external WG on the other side of the engine at beginning of the X pipe,this will solve the pulses issue (now where do I find another VR6t car in breakage )

[Barry]