GT4088 split (divided) turbine housing.

[Mars]

How much difference if any does it make to run 1-3-5 and 2-4-6 to each side of the division ?

AND is doing this even worth it if you only have 1 wastegate (which would join the hotside banks anyways so that it can bleed off exhaust)

The theory behind everything is to try to avoid the exhuast pulses from "hitting" against each other... but if I have to join both banks before the turbine for the wastegate isn't it not going to really do anything ?

Or did I miss something ?

[timg]

I would run each side of the engine to it's own volute on the turbine housing. Even with just one wastegate, it will matter. You should try to use divided flanges and two wastegates on a divided turbo whenever possible. Not doing so can result in poor spool and poor efficiency. Sometimes, single wastegates are used if the exhaust gas streams are kept divided all the way to the valve. All of this is most important with a good, equal length turbo manifold. With log manifolds, all of the above becomes much less important.

Tim

[BlackJack]

**edited - I miss read the question.

[MidnightriderZ24]

honestly i think it helped spool time.. i used a 2-1 collector, cut it open and divided both sides. tapped into both ends. no spikes, or issues at the moment with a 50mm wastegate.

[Driver_10]

GT4088, huh? Pretty ambitious. If I may ask, what type/size turbine housing are you using?

[Mars]

77mm inducer
68mm exducer
78 trim turbine
0.95 A/R

61mm inducer
88mm exducer
48 trim compressor
0.72 A/R

[Driver_10]

77mm inducer
68mm exducer
78 trim turbine
0.95 A/R

61mm inducer
88mm exducer
48 trim compressor
0.72 A/R

This is actually pretty similar to the CT-62 turbocharger that im using. The major notable difference is that Ill be using a billet 62mm compressor-wheel (flows like a 67mm due to the greater surface area of the thinner cut blades) and a larger exhaust housing (1.0 A.R. t3 divided tang housing)

Tell me, are you using an anti-surge shroud as well?

[Mars]

Yeah it's an anti surge housing. I have a BOV though and the car is auto, so I likely don't really need it... but it's there.

I wish I could find a compressor map for my 48 trim wheel, but, after searching... I cannot. Seems like a small 61mm inducer for an 88mm exducer, but the price was right.



There it is beside my t3/t4 59mm turbo. cute.

[--X--]

I would run each side of the engine to it's own volute on the turbine housing. Even with just one wastegate, it will matter. You should try to use divided flanges and two wastegates on a divided turbo whenever possible. Not doing so can result in poor spool and poor efficiency. Sometimes, single wastegates are used if the exhaust gas streams are kept divided all the way to the valve. All of this is most important with a good, equal length turbo manifold. With log manifolds, all of the above becomes much less important.

Tim

I agree with Timg all the way except with log manifold statement. Now if you are referring to the OEM log then yes, however if you are saying a well designed log "becomes much less important" then absolutely no

not mine

The science suggest actually to keep the exhaust length as short as practically possible to keep more of the heat and pressure till it expands in the volute by giving off said energy to different parts of the 'hot wheel'. As already stated you should keep each housing completely divorced and one can even go up a housing (exhaust A/R for even more benefit). Of course if this is a street car then you might want to keep the housing you already have

[Mars]

Hi again,

ok, so I think I've decided to go with dual 38mm gates.

My last gate was a 50mm 50$ ebay knockoff and it works flawless with my Greddy EBC. So why not spend a 100$ and get dual 38's keep the banks seperated...

Question :

would this location be alright for dual gates or do they NEED to be right beside each other just before entering the turbine ??

It's just that with the headers, oil drain, ect ect it would be nice if I could keep one of the gates a little closer to the drivers side...

thanks.

[--X--]

Hi again,

ok, so I think I've decided to go with dual 38mm gates.

My last gate was a 50mm 50$ ebay knockoff and it works flawless with my Greddy EBC. So why not spend a 100$ and get dual 38's keep the banks seperated...

Question :

would this location be alright for dual gates or do they NEED to be right beside each other just before entering the turbine ??[ATTACH=CONFIG]5231[/ATTACH]

It's just that with the headers, oil drain, ect ect it would be nice if I could keep one of the gates a little closer to the drivers side...

thanks.

Cool! I have always been told both gates as close to the turbine as possible, especially for better response and control. Plus it is better to tee the vacuum lines from one source, the wgs will have to be closer for this. How are you planning on configuring the turbo? N-S (90^) or W-E (parallel) to the engine? You can run a pipe along side both primaries to give you room for the Wgs?

[Mars]

I want to keep the turbo in more or less the same location as it is now. I like how the exhaust goes straight back and I like the oil drain angle from the turbo, good drainage angle. I think the way I have it layed out in my head it'll work out fine with the dual 38's. Might not be 100% ideal, but should work.

I just ordered the gates today as I type this.

and what do you know my 60#/hr Mototron injectors just came in as well.

The rest of the buildup is here (old smaller turbo and old junkyard ABUSED 3400V6)

3400T camaro buildup TH350

[--X--]

I want to keep the turbo in more or less the same location as it is now. I like how the exhaust goes straight back and I like the oil drain angle from the turbo, good drainage angle. I think the way I have it layed out in my head it'll work out fine with the dual 38's. Might not be 100% ideal, but should work.

I just ordered the gates today as I type this.

and what do you know my 60#/hr Mototron injectors just came in as well.

The rest of the buildup is here (old smaller turbo and old junkyard ABUSED 3400V6)

3400T camaro buildup TH350

lol Mars you make everything look easy. As long as they are using the same vacuum source I am sure you will be definitely ok. Read up on pulse turbocharging; to get more on your research.
BTW it is a nice build, I can't believe you still have that cav hehehe
what A/R is your exhaust housing? sorry not sure if you already posted it!?!?

[Mars]

Specs on my current turbo :

T4 twinscroll / 3" Vband outlet
78 trim turbine
0.95 A/R

54 trim compressor
65mm inducer
88mm exducer
0.72 A/R



I think I mapped that out correctly... Give or take, but it's right in the efficient range, it kills my old 60-1 turbo. Deadly in the 12 - 20 PSI range.

[--X--]

Holy Cowz, thats like a 10% difference. Yeah them ol' 60 dashes were the ishes back in the day, they should die a wonderful death lol My brother used to have the 60-1 and upgraded to a 62 dash ah those were the days lol. It will be definitely interesting to see how this works since you are using a tubular "equal" length header system.
You will also love the way it sounds...