[Telion]

I have a question, what is teh benefit of having the X-pipe before between the headers and the turbos? Grumps did I understand that correct?

 

[hybirdgsrlegend]

as much as we all love twins telion.. my 2 cents would be to use one big turbo say like a garett 60 trim>?, place it where the ac goes but hey its your car

 

[Telion]

I had considered placing one of the turbos there but then I thought what fun is that I (and everyone else) can see.

 

[GrumpySteelMan]

I have a question, what is teh benefit of having the X-pipe before between the headers and the turbos? Grumps did I understand that correct?

Yes, you got that correct. Since you're packaging the turbos so close together I would suggest that, if possible, so you'll get even bank to bank distribution of exhaust flow coupled with the smaller diameter pipe your velocity and heat will stay higher. In fact if you could build your pre-turbo y or x-pipe out of heavy schedule 40 (aka weld els) iron pipe, you'd be even better off in the heat department. I would highly suggest that.

Whatever you do, don't merge from the headers into 3" and then split off into the turbo inlets. You'll be wasting tons of heat and velocity with the large diameter tube. You'd be much better off running dedicated 2.25" (2.5" is probably too large) pipes to the inlet of each turbo and then merging afterwards into your single 3" exhaust. If you're going to run a y-pipe at the headers, then I'd run a single 2.5" to the turbos and then y- off from there.

If you'll look at the actual size of the throats in those turbine housings, they're probably 2-2.5 sq in. A 3" pipe has ~7 sq in of area. You see the mismatch here? A 2.5" pipe has an area of ~4.9 sq in. A 2.25" has an area of ~4 sq in. Do you see my argument for a single 2.5" pipe? or twin 2.25"?

Even in NA applications (although mainly odd fire V-8s, not on even fire 90 deg V-6s) the equal bank to bank pressures are important, since the intake manifold is shared, you don't want 3cylinders with more restriction the the other 3, which would affect the cylinder inlet charge and reduce power output...this is nearly the same issue as the wastegate settings. If there is 2psi greater restriction on bank 1 than bank 2, the spent gases will evacuate better on bank 2 and bank 1 will have a more contaminated intake charge. This is really a nit picky thing, for the budget minded guy, you probably should skip the pre-turbo x-pipe idea...but definitely don't y-into anything larger than a 2.5" pipe.

If you go to the 3" pipe off the Y from the headers then neck back down into the turbos you are losing both velocity and heat as compared to twin 2.25" pipes, whether you use an x-pipe or not. Using the x-pipe (or y-pipe) after the turbos won't help equalize bank to bank pressures nearly as well, but thats probably not important for your application.

The turbo exhaust needs to be large after the turbos to increase the temperature (and pressure) differential across the turbine blades.

For example you can run a 3" downpipe, 2.75" from cat to muffler with 2.5" outlet with little to no loss in performance. As the temperature drops the gas becomes more dense and the pipe diameter must be decreased to maintain constant velocity. Of course this is one of those nit picking points. I've done a 4" DP to a 3" full exhaust before, just because I had the pipe and the bends laying around.

Sorry if there are any contradictions... I'm trying to keep your total scope in mind...budget, etc. I tend to get stuck on maximum effort.

as much as we all love twins telion.. my 2 cents would be to use one big turbo say like a garett 60 trim>?, place it where the ac goes but hey its your car

60-trim, that's helpful. That could be either a T3, T04E, or a T3/T04E...all radically different turbos.

Go spend your 2cents on your 300whp Legend.

 

[Telion]

Ok while I read can anyone think of what else I need such as oil lines which AN size? And would it be beneficial to get a turbo timer?

 

[reboticon]

The benefit of the x-pipe is to equalize the exhaust pressure on all cylinders AND equilize inlet pressure at the turbos.

So when using twin turbos, lets say they each can push 6psi. Is the wastegate going to be set to 12psi, assuming you are using one intake for both?

edit: eh started posting before grumps long explanation showed up.

 

[GrumpySteelMan]

So when using twin turbos, lets say they each can push 6psi. Is the wastegate going to be set to 12psi, assuming you are using one intake for both?

Wrong. 6psi would be the total pressure unless you're doing compound turbocharging...and that's a totally different deal altogether. As I said, each turbo would make the same pressure but you would have double the airflow.

 

[Telion]

Yes, you got that correct. Since you're packaging the turbos so close together I would suggest that, if possible, so you'll get even bank to bank distribution of exhaust flow coupled with the smaller diameter pipe your velocity and heat will stay higher. In fact if you could build your pre-turbo y or x-pipe out of heavy schedule 40 (aka weld els) iron pipe, you'd be even better off in the heat department. I would highly suggest that.

Whatever you do, don't merge from the headers into 3" and then split off into the turbo inlets. You'll be wasting tons of heat and velocity with the large diameter tube. You'd be much better off running dedicated 2.25" (2.5" is probably too large) pipes to the inlet of each turbo and then merging afterwards into your single 3" exhaust. If you're going to run a y-pipe at the headers, then I'd run a single 2.5" to the turbos and then y- off from there.

Ok here I am considering doing a U shape. Imagine the top of one side of the U connecting to the header then routing to the otherside and going to a turbo on the opposite side of the U. With 2.5" piping so two U's total this will be stainless steel. The purpose of the U to the opposite side is to minimize the degree of the bend. Then the turbo to the intercooler will be 2.5"aluminum, and the intercooler to the TB will be 3" as we all already know, now on the hotside, it will also be 2.5" inches off the turbos to a 2.5" X-pipe that will route to either a two in two out muffler or a set of mufflers (I am leaning toward the latter of the two)

If you'll look at the actual size of the throats in those turbine housings, they're probably 2-2.5 sq in. A 3" pipe has ~7 sq in of area. You see the mismatch here? A 2.5" pipe has an area of ~4.9 sq in. A 2.25" has an area of ~4 sq in. Do you see my argument for a single 2.5" pipe? or twin 2.25"?
True I believe they are 2.25"

The turbo exhaust needs to be large after the turbos to increase the temperature (and pressure) differential across the turbine blades.

For example you can run a 3" downpipe, 2.75" from cat to muffler with 2.5" outlet with little to no loss in performance. As the temperature drops the gas becomes more dense and the pipe diameter must be decreased to maintain constant velocity. Of course this is one of those nit picking points. I've done a 4" DP to a 3" full exhaust before, just because I had the pipe and the bends laying around.

Off the downpipes do you think a set of 2.5 to the x-pipe then out to a set of straight through mufflers would be fine?

Sorry if there are any contradictions... I'm trying to keep your total scope in mind...budget, etc. I tend to get stuck on maximum effort.

Get stuck because I wanna here best case to budget and choose from there!

 

[GrumpySteelMan]

Ok while I read can anyone think of what else I need such as oil lines which AN size? And would it be beneficial to get a turbo timer?

Turbo timer is always a good idea, but you probably don't need it.

Like I said -4AN lines for feed. 1/2" ID high temp hose for return.

Ok here I am considering doing a U shape. Imagine the top of one side of the U connecting to the header then routing to the otherside and going to a turbo on the opposite side of the U. With 2.5" piping so two U's total this will be stainless steel. The purpose of the U to the opposite side is to minimize the degree of the bend

Wow, that makes almost no sense. Minimizing the bend radius isn't anywhere near as important as MINIMIZING THE DISTANCE between the collector and the turbo. Longer than needed piping runs are really just as crazy as running a single 3" pipe prior to splitting off for the turbos.

Skip the stainless steel. It expands twice as much as mild steel, which means it is more prone to distortion and stress fractures. It's also harder to work with and is considerably more expensive.

True I believe they are 2.25"

Not the diameter of the turbo inlet, the area of the throat at the beginning of the neckdown. The actual internal diameter is probably less than 2".

...now on the hotside, it will also be 2.5" inches off the turbos to a 2.5" X-pipe that will route to either a two in two out muffler or a set of mufflers (I am leaning toward the latter of the two)

Off the downpipes do you think a set of 2.5 to the x-pipe then out to a set of straight through mufflers would be fine?

2.5" downpipes to a y-pipe and a 3" back...no reason to put an x-pipe post turbo, a waste of money and more complex for absolutely no gain.

 

[Telion]

To help visualize what I have so far other than what is seen I will do a quick run down with some pics. This will also double as my check off list.

255lph walbro fuel pump
a couple adjustable FPR's (not a rising-rate fuel pressure regulator)

450cc DSM injectors
a Top fuel Zero1000 BOV

a Top fuel Zero1000 oil catch can

2.5" aluminum intercooler piping (This will need to be x2)

2.5" stainless steel exhaust piping

2.5" X-pipe

Ok already I can see that I am going to need a set of couplers that go from the turbo to the intercooler piping.

I will need a couple filters for the turbos (any ideas?)
Flanges for the turbos/piping

 

[Telion]

Turbo timer is always a good idea, but you probably don't need it.

Like I said -4AN lines for feed. 1/2" ID high temp hose for return.
Gotcha, now what about the water cooling side the turbos?

Wow, that makes almost no sense. Minimizing the bend radius isn't anywhere near as important as MINIMIZING THE DISTANCE between the collector and the turbo. Longer than needed piping runs are really just as crazy as running a single 3" pipe prior to splitting off for the turbos.

Skip the stainless steel. It expands twice as much as mild steel, which means it is more prone to distortion and stress fractures. It's also harder to work with and is considerably more expensive.
My mistake it is 16 ga aluminized steel.

Not the diameter of the turbo inlet, the area of the throat at the beginning of the neckdown. The actual internal diameter is probably less than 2".
Ooohhh my bad lol I don't have a clue on that one.

2.5" downpipes to a y-pipe and a 3" back...no reason to put an x-pipe post turbo, a waste of money and more complex for absolutely no gain.

Looks like I missed how this was applied on Hotlava's setup tip. But I can see now that it is between the turbos and the FMIC.

 

[Telion]

Ok I received the X-pipe and I am not too impressed. I will put up pics later but the interior walls have the pipe extruding from them so the air flow will be disrupted even though it is a 1/4 in at its greatest point on each interior wall that you can see the pipe that tells me not much time went into the getting the setup correct before mass producing them I was much happier with the flowmasters Y-pipe design which I had initially thought this would be similar to. so others don't make the same mistake it was an Ebay co. built4race. I guess it can't be better said than you get what you pay for (unless it is a steal of a deal or on clearnace).

 

[DandDEE]

this thread confuses me in so many levels... i will try to read this over and over to understand, i hope to see master Telion on Pass time or Pinks after this project is finished... btw im freakin confused???!

 

[Boondock Saint]

turbo yum

 

[Telion]

Ok here is a couple pics of my current train of thought, I have always liked seeing a set of twins off to the side at the same angle, plus if I get a coupple 45 elbos or maybe some of that dryer hose stuff and a broken JDM passenger headlight I can create a "race-time ram air" and port them directly through the headlight. I have also decided to dump the running a seperate exhaust for each and opeted to go with doing a Y off each one in the engine bay to a 3" exhaust all the way back (room to grow). And yep the hood closes

PS Grumps thanks for bumpin the SC thread I forgot a piping optin till looking at it.

Normally these are the sort of pics you would not see as I am working through my ideas but I really like working this way and getting feedback as I go vs. I did it what do you think. (Pics of progress which depict action)

Personal reminder Normally I do all this in Word so I dont forget.
get better heater core hoses and shield them from the pipe on the firewall and move power wires back there.
-ZEX has purple intake filters
-shield the MAP box
-consider mounting the X-pipe under the car after ex. manifold before and to the turbos.

 

[legendfire]

i was jw if its possible to modify the exhaust manifolds from a tt 350z kit to fit on the rl engine? because that might make things easier as far as plumbing goes.

 

[Telion]

I wonder that myself every day lol. Just cut the flanges have a set of custom flanges made and welded to the exhaust manifolds of the 350Z. Does anyone have access to the gaskets for each of these, to see how far off the holes are?

 

[Dethred]

Whoa whoa whoa, we're getting away from a solution here. Kyle already made flanges. 350Z manifolds? Why not just use the OBX header design.

Why not place the other turbo near where the battery is (remove battery and relocate relay box)? If you're going to run the driver's side manifold all the way to a turbo 5 inches away from the other, then it'd be smarter, cheaper, and easier to go with a single. I know the twins will spool better, but you're going to have nearly 3ft between the closest combustion on the driver's side cylinder bank and the turbo. Honestly, if you want this to work well you're going to want each turbo as close to the manifold collector as possible (Cpt. Obvious reporting for duty).

Remove the battery and see what you're dealing with. Either way you cut it, you're going to be removing something more than the battery.

 

[legend4life]

I wonder that myself every day lol. Just cut the flanges have a set of custom flanges made and welded to the exhaust manifolds of the 350Z. Does anyone have access to the gaskets for each of these, to see how far off the holes are?

I have two sets of custom cnc machined 1/2" thick mild steel Legend head flanges for sale, along with many other parts carefully chosen for a Legend twin turbo setup. I also have plans/pictures if you're interested just e-mail me for them.

http://www.acura-legend.com/vbullet.../f38/fs-94-gs-6mt-blk-blk-92-ls-coupe-silver-lots-mods-parts-upstate-ny-124802/

 

[reboticon]

350 TT manifolds. Already have second port to turbo.Thats why they are thinking of them instead of the OBX, i believe? Everyone but Telion wants a turbo to end up where the battery used to be

Telion- your "projects" move along at a much faster rate than most people average, self included. Lookin good:thumbsup:

I think if you put both turbos right there, you may have one taking longer to spool than the other. Im my head that doesn't seem like that big of deal as long as they share a common intake plenum.

DandDEE - you aren't alone, this thread makes my brain hurt. Its funny the difference between one of grumpys posts here and in the lounge. Both of them make my head hurt but from different spectrums