Twinscroll worth it?
#41
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I think that twin scroll is a waste of time and money in 99.999% of situations.
In Subaru land (where i am from) twin scroll pops around a bit on random builds and almost never do you see real gains when you overlay graphs/compare time slips/driveability. Often twin scroll setups (example a pte6262 on a Subaru) choke up top because of the design.
In Subaru land (where i am from) twin scroll pops around a bit on random builds and almost never do you see real gains when you overlay graphs/compare time slips/driveability. Often twin scroll setups (example a pte6262 on a Subaru) choke up top because of the design.
I dont doubt that it probably doesnt make much of a difference on your typical drag car that never leaves boost, but if it doesnt show up on a dyno its either a fucked up setup, or they started the dyno pull at 4k rpm. It seems like most dyno shops do this (because theyre stupid).
#42
They must be doing something wrong.
I dont doubt that it probably doesnt make much of a difference on your typical drag car that never leaves boost, but if it doesnt show up on a dyno its either a fucked up setup, or they started the dyno pull at 4k rpm. It seems like most dyno shops do this (because theyre stupid).
I dont doubt that it probably doesnt make much of a difference on your typical drag car that never leaves boost, but if it doesnt show up on a dyno its either a fucked up setup, or they started the dyno pull at 4k rpm. It seems like most dyno shops do this (because theyre stupid).
No the car we are talking about is not a drag car it is just a fun weekend car. I said yes it shows spool gains but only for you to jerk off at the dynograph (slightly 300rpm or so isn't ANYTHING) on the street there will never be a noticeable difference. The weather outside and DA at the time will probably effect your butt dyno more then twin scroll vs single.
Gains yes..on paper...reality very small while also having its downsides
The title of this thread is twin scroll "worth it" ..my response and OPINON was no.
#43
That right there is why Subarus don't respond well to twin scroll. There is too much volume in the exhaust, and the exhaust pulses just kind of disappear, compared to a short runner style like most inline engines. The exhaust pulsing is what makes twin scroll efficient, pairing companion cylinders to even out the pulses and when they impart their energy on the exhaust turbine. And yes I am familiar with the Subaru world, had an 04 STi and 05 STi (blob eyes are my favorite other than a GC RSTi). With short runner systems, twin scroll makes an immidiate difference in not only initial spool up/thresh hold, but also in transient characteristics. My Evo X with a Full-Race twin scroll manifold and EFR 7670 has way better transient characteristics compared to my 04 STi with an 18g on it, and isn't far behind my old stock turbo'd 05 with full bolt on's, stock top mount, catless 3" turbo back. Short runner single scroll is even better than Subarus design on the EJ engines. I mean, Subaru has even switched to a shorter runner, twin scroll configuration on the new FA series engines.
#44
Come on guys, the twin scroll is a "bit" more responsive. If you ask it to do its job on an unsuitable combination of pieces you will not be impressed.
There are a couple ts variations. Have any of you seen the tc layout that actually carried the separation all the way to the turbine blades? Or, almost all the way? The very first RX7 factory turbo used a variation of the gated housing, and it was less than impressive. The same turbo we used on the Mustang (a single guy) offered a better response than the Mazda gated feature. Mazda clearly had the wrong turbo.
A few moons ago Aerodyne asked me to make patterns for a one piece exhaust manifold/exh housing. It was a four syllable Mercedes Diesel, and the pulses arrived at the turbine in four separate paths, yet with enough force to begin cracking the turbine blades. Damn Aerodynes. Never saw cracked blades before or since. Responsive it was.
Sure, there are better turbo designs than the commie pinko things. For limited power applications and about 1/4th the cost, you can't raise too much of a fuss. It is cheaper and it works okay. If the size is appropiate, it too will work a tick better with the ts stuff.
Would I select a ts for my own turbo Miata? Probably not. My objectives are long black lines on the asphalt.
What are your's?
corky
There are a couple ts variations. Have any of you seen the tc layout that actually carried the separation all the way to the turbine blades? Or, almost all the way? The very first RX7 factory turbo used a variation of the gated housing, and it was less than impressive. The same turbo we used on the Mustang (a single guy) offered a better response than the Mazda gated feature. Mazda clearly had the wrong turbo.
A few moons ago Aerodyne asked me to make patterns for a one piece exhaust manifold/exh housing. It was a four syllable Mercedes Diesel, and the pulses arrived at the turbine in four separate paths, yet with enough force to begin cracking the turbine blades. Damn Aerodynes. Never saw cracked blades before or since. Responsive it was.
Sure, there are better turbo designs than the commie pinko things. For limited power applications and about 1/4th the cost, you can't raise too much of a fuss. It is cheaper and it works okay. If the size is appropiate, it too will work a tick better with the ts stuff.
Would I select a ts for my own turbo Miata? Probably not. My objectives are long black lines on the asphalt.
What are your's?
corky
#45
see bold
That's cool. I acknowledge your OPINION. The other crap is stupid drivel.
We are not NABISCO. Check-book builders don't get to talk smack here. Only people that actually do things/ prove things do. No one cares what your tuner or his wife or their cousin or your homie or his dog said or did. Twin scroll is not pointless.
I think that twin scroll is a waste of time and money in 99.999% of situations.
In Subaru land (where i am from) twin scroll pops around a bit on random builds and almost never do you see real gains when you overlay graphs/compare time slips/driveability. Often twin scroll setups (example a pte6262 on a Subaru) choke up top because of the design.
I would argue the exact opposite: in subaru land, where I'M FROM, TS does exactly what it's supposed to do, which is increase lowend/spool at the cost of a bit of topend. Countless dyno plots show this, with the exception of subaru's own OEM TS setup when fitted to a EJ25, because the vf series only helps the 207 and the like, and can't really do much for the EJ25x. Once you go bigger, it's a different ball game. I can post the plots, but you practically live in PPB so you know
Ok now lets think when you will actually use the benefits of a twin scroll setup.
When is the last time you were going wot at say 2,500 rpm?
all....the..........time.
on all 5 of my subaru's and all 5 of my miata. I'm sorry that we're regular people and not freeway racers or drag queens (pun intended) like you.
Why were you going wot at 2,500??
because that's when sane people spend 99% of their time daily driving, and torque/transient response is very important to us.
High load low rpm situations are very stressful to many components IE the weak rods in these cars even upgraded stress is stress I have managed a bend turbo tuff I beam rod/bolt with enough will power in my Subaru when with enough playing around we got spool of the average 62mm turbo but then made the power of a 68mm turbo that was actually on it (mid 30psi at 4,900 rpm in only 3rd gear).
who cares? we mod our cars to make power where and when we want. I'm not gonna limp my car til 5k when the stupid oversized snail will finally hit. been there, done that, sold that car.
What about traction? A linear powerband that comes on smooth will not only save stress on every component in the entire driveline but it will also help aid in actually being able to use the power your trying to make.
a big turbo single scroll will NEVER come on any more smooth than TS. Sorry. I'm sure you've seen countless evo plots showing this, I won't even waste any more time on this argument
I only seeing this useful in situations where people are using turbos so large for the car that being able to create a nice solid powerband actually becomes a issue considering your not actually racing at 3,000 rpm and it only hurts top end.
In Subaru land (where i am from) twin scroll pops around a bit on random builds and almost never do you see real gains when you overlay graphs/compare time slips/driveability. Often twin scroll setups (example a pte6262 on a Subaru) choke up top because of the design.
I would argue the exact opposite: in subaru land, where I'M FROM, TS does exactly what it's supposed to do, which is increase lowend/spool at the cost of a bit of topend. Countless dyno plots show this, with the exception of subaru's own OEM TS setup when fitted to a EJ25, because the vf series only helps the 207 and the like, and can't really do much for the EJ25x. Once you go bigger, it's a different ball game. I can post the plots, but you practically live in PPB so you know
Ok now lets think when you will actually use the benefits of a twin scroll setup.
When is the last time you were going wot at say 2,500 rpm?
all....the..........time.
on all 5 of my subaru's and all 5 of my miata. I'm sorry that we're regular people and not freeway racers or drag queens (pun intended) like you.
Why were you going wot at 2,500??
because that's when sane people spend 99% of their time daily driving, and torque/transient response is very important to us.
High load low rpm situations are very stressful to many components IE the weak rods in these cars even upgraded stress is stress I have managed a bend turbo tuff I beam rod/bolt with enough will power in my Subaru when with enough playing around we got spool of the average 62mm turbo but then made the power of a 68mm turbo that was actually on it (mid 30psi at 4,900 rpm in only 3rd gear).
who cares? we mod our cars to make power where and when we want. I'm not gonna limp my car til 5k when the stupid oversized snail will finally hit. been there, done that, sold that car.
What about traction? A linear powerband that comes on smooth will not only save stress on every component in the entire driveline but it will also help aid in actually being able to use the power your trying to make.
a big turbo single scroll will NEVER come on any more smooth than TS. Sorry. I'm sure you've seen countless evo plots showing this, I won't even waste any more time on this argument
I only seeing this useful in situations where people are using turbos so large for the car that being able to create a nice solid powerband actually becomes a issue considering your not actually racing at 3,000 rpm and it only hurts top end.
The rotary guys at least try to make power at times.
That's funny, please post up your 500whp miata so we can all marvel at it. If you don't have one, then I won't even tell you how dumb statements like this sound, I'll just assume you already know.
How many Miata guys here are trying to make 5-6-700whp where spool is needed quickly so they can try to make a good powerband and stay in it.
If your having spooling issues trying to make a 250whp-300whp car its because you choose a poverty ebay turbo or some other random cheap $250 turbo you found on the forums (Miata guys are famous for this)
Oh really? So you know the miata scene? That's cool. Please post up your baller EFR/GTX build.
. A simple efr or bullseye turbo will make it a completely different car but turbos are turbos right only twin scroll can help .
Probably the dumbest thing you said so far, and you're really trying in this thread.
you can take your attitude and shove it where the sun don't shine.
last I saw you failed making big power, blew your crap, and parted it out, putting the car back to near stock. build a big power fast miata then talk.....mmmmmmmmmmmmkay?
I have seen a local buddy go with a twin scroll pte62 setup.....after talking to his tuner while his car was being tuned on the dyno (one of if not the biggest GTR/SUBARU/EVO tuners in the US) they switched over to a pte62 with a single scroll setup after that season and that's what he is on now.
here in the miata scene we don't all "talk to the tuner" like 99% of nabisco. We build and tune our own cars. almost all of us.
He admitted that there was never a single time where twin scroll actually provided something for him and all it did was start to hurt up top.
I've got a buddy that heard the exact opposite of what you're saying from the best tuner known to mankind proving that whatever I say is right and I'm the coolest person on here. *dropmike*
While I admit it may have benefits with some random auto x and even less track guys what % are actually going to purchase this twin scroll setup and all the other goodies like the extra wastegate, retune ect all for 300 rpm of spool. Will they even notice the difference and actually do anything besides help you jerk off to your dyno graph?
funny you should say that. after talking about "high hp record this, 600whp that"
That's funny, please post up your 500whp miata so we can all marvel at it. If you don't have one, then I won't even tell you how dumb statements like this sound, I'll just assume you already know.
How many Miata guys here are trying to make 5-6-700whp where spool is needed quickly so they can try to make a good powerband and stay in it.
If your having spooling issues trying to make a 250whp-300whp car its because you choose a poverty ebay turbo or some other random cheap $250 turbo you found on the forums (Miata guys are famous for this)
Oh really? So you know the miata scene? That's cool. Please post up your baller EFR/GTX build.
. A simple efr or bullseye turbo will make it a completely different car but turbos are turbos right only twin scroll can help .
Probably the dumbest thing you said so far, and you're really trying in this thread.
you can take your attitude and shove it where the sun don't shine.
last I saw you failed making big power, blew your crap, and parted it out, putting the car back to near stock. build a big power fast miata then talk.....mmmmmmmmmmmmkay?
I have seen a local buddy go with a twin scroll pte62 setup.....after talking to his tuner while his car was being tuned on the dyno (one of if not the biggest GTR/SUBARU/EVO tuners in the US) they switched over to a pte62 with a single scroll setup after that season and that's what he is on now.
here in the miata scene we don't all "talk to the tuner" like 99% of nabisco. We build and tune our own cars. almost all of us.
He admitted that there was never a single time where twin scroll actually provided something for him and all it did was start to hurt up top.
I've got a buddy that heard the exact opposite of what you're saying from the best tuner known to mankind proving that whatever I say is right and I'm the coolest person on here. *dropmike*
While I admit it may have benefits with some random auto x and even less track guys what % are actually going to purchase this twin scroll setup and all the other goodies like the extra wastegate, retune ect all for 300 rpm of spool. Will they even notice the difference and actually do anything besides help you jerk off to your dyno graph?
funny you should say that. after talking about "high hp record this, 600whp that"
Pretty sure if they can build and tune GTRS and subarus that trap 170+ mph they can figure out when to start a pull on the dyno.
pretty sure no one tuning for the drag strip cares about 3k rpm. pick a better, non-retarded and not self contradictory argument next time, k?
No the car we are talking about is not a drag car it is just a fun weekend car. I said yes it shows spool gains but only for you to jerk off at the dynograph (slightly 300rpm or so isn't ANYTHING) on the street there will never be a noticeable difference. The weather outside and DA at the time will probably effect your butt dyno more then twin scroll vs single.
300rpm is a lot, and the transient response improvement that comes with it is even more noticeable. for us mere peasants who don't live our life a quarter mile at a time.
Gains yes..on paper...reality very small while also having its downsides
gains on paper show gains in reality. shut your stupid troll mouth
The title of this thread is twin scroll "worth it" ..my response and OPINON was no.
pretty sure no one tuning for the drag strip cares about 3k rpm. pick a better, non-retarded and not self contradictory argument next time, k?
No the car we are talking about is not a drag car it is just a fun weekend car. I said yes it shows spool gains but only for you to jerk off at the dynograph (slightly 300rpm or so isn't ANYTHING) on the street there will never be a noticeable difference. The weather outside and DA at the time will probably effect your butt dyno more then twin scroll vs single.
300rpm is a lot, and the transient response improvement that comes with it is even more noticeable. for us mere peasants who don't live our life a quarter mile at a time.
Gains yes..on paper...reality very small while also having its downsides
gains on paper show gains in reality. shut your stupid troll mouth
The title of this thread is twin scroll "worth it" ..my response and OPINON was no.
We are not NABISCO. Check-book builders don't get to talk smack here. Only people that actually do things/ prove things do. No one cares what your tuner or his wife or their cousin or your homie or his dog said or did. Twin scroll is not pointless.
Last edited by 18psi; 07-06-2015 at 12:14 AM.
#46
LOL
"last I saw you failed making big power, blew your crap, and parted it out, putting the car back to near stock. build a big power fast miata then talk.....mmmmmmmmmmmmkay?"
First off...the car is not going back to stock. It still has a built motor/heads cams e85 52mm bullseye turbo ect now i am in the process of assemballing in my little spare time i get so i can start tearing apart the miata for gasp that "higher" hp build you just called me out for not attempting to do. IF parted out means sold my 2000cc injectors i didnt need anymore, and my processwest intake manifold then sure i parted out my car. I only sold the things i did not need for the next setup i still even have the old turbo incase i ever decide to put it on either project car. Also if failed means many mid 10 second passes (still holding the MI subaru et and trap record) and daily driven for a couple months including winter before throwing a bigger turbo on and cranking it out on e98 till it bent some stuff sure i failed lol.
"here in the miata scene we don't all "talk to the tuner" like 99% of nabisco. We build and tune our own cars. almost all of us,"
Maybe because tuning a baby turbo run of the mill miata is a tiny bit easier then getting 2000cc injectors on speed density e85 ect to all work together start in negative degree michigan winters ect and to make a driveable car so you can actually drive it to work when youd like too. I leave that to the guy that knows what he is doing sorry that upsets you lol.
"gains on paper show gains in reality. shut your stupid troll mouth"
No you will NEVER Feel the difference of 300rpm in spool on the street day to day twin scroll will not whats so ever be some kind of saving grace and will only be an added expense to a group who you just admitted doesnt build with their checkbook. Get over your self .
I like the turbomiata forums its like a bunch of little uncle scottys running around telling everyone how great they are lmao.
I will now retire back to lerking these forums as i have for many years .
"last I saw you failed making big power, blew your crap, and parted it out, putting the car back to near stock. build a big power fast miata then talk.....mmmmmmmmmmmmkay?"
First off...the car is not going back to stock. It still has a built motor/heads cams e85 52mm bullseye turbo ect now i am in the process of assemballing in my little spare time i get so i can start tearing apart the miata for gasp that "higher" hp build you just called me out for not attempting to do. IF parted out means sold my 2000cc injectors i didnt need anymore, and my processwest intake manifold then sure i parted out my car. I only sold the things i did not need for the next setup i still even have the old turbo incase i ever decide to put it on either project car. Also if failed means many mid 10 second passes (still holding the MI subaru et and trap record) and daily driven for a couple months including winter before throwing a bigger turbo on and cranking it out on e98 till it bent some stuff sure i failed lol.
"here in the miata scene we don't all "talk to the tuner" like 99% of nabisco. We build and tune our own cars. almost all of us,"
Maybe because tuning a baby turbo run of the mill miata is a tiny bit easier then getting 2000cc injectors on speed density e85 ect to all work together start in negative degree michigan winters ect and to make a driveable car so you can actually drive it to work when youd like too. I leave that to the guy that knows what he is doing sorry that upsets you lol.
"gains on paper show gains in reality. shut your stupid troll mouth"
No you will NEVER Feel the difference of 300rpm in spool on the street day to day twin scroll will not whats so ever be some kind of saving grace and will only be an added expense to a group who you just admitted doesnt build with their checkbook. Get over your self .
I like the turbomiata forums its like a bunch of little uncle scottys running around telling everyone how great they are lmao.
I will now retire back to lerking these forums as i have for many years .
#47
I feel 300rpm in spool every single day, on the numerous cars I have the privilege of modding and tuning. You might want to look up transient response, I'm sure you don't even comprehend the concept with your ex-10 or 9 sec or whatever it is, subaru.
You will swing e-**** when you achieve something with a miata. You have no idea how ignorant you sound with the "little baby 300hp miata tuning" statement. Everyone that comes from other platforms always acts the fool and a complete douchebag like you, cause they think they're just SOOOo much better than us. Then they fail miserably or pay someone to do everything for them, cause all they know is how to write a check and swing peen on the interwebz. It's just a dinky miata, how hard could it possibly be to tune, right?
I've tuned ID2000's on speed density. Have you? Personally? Come at me bro.
Uncle Scotty wouldn't last in here for more than 5 minutes. Go ahead and tell him to join. I dare you.
You will swing e-**** when you achieve something with a miata. You have no idea how ignorant you sound with the "little baby 300hp miata tuning" statement. Everyone that comes from other platforms always acts the fool and a complete douchebag like you, cause they think they're just SOOOo much better than us. Then they fail miserably or pay someone to do everything for them, cause all they know is how to write a check and swing peen on the interwebz. It's just a dinky miata, how hard could it possibly be to tune, right?
I've tuned ID2000's on speed density. Have you? Personally? Come at me bro.
Uncle Scotty wouldn't last in here for more than 5 minutes. Go ahead and tell him to join. I dare you.
#48
I feel 300rpm in spool every single day, on the numerous cars I have the privilege of modding and tuning. You might want to look up transient response, I'm sure you don't even comprehend the concept with your ex-10 or 9 sec or whatever it is, subaru.
You will swing e-**** when you achieve something with a miata. You have no idea how ignorant you sound with the "little baby 300hp miata tuning" statement. Everyone that comes from other platforms always acts the fool and a complete douchebag like you, cause they think they're just SOOOo much better than us.
I've tuned ID2000's on speed density. Have you? Personally? Come at me bro.
Uncle Scotty wouldn't last in here for more than 5 minutes. Go ahead and tell him to join. I dare you.
You will swing e-**** when you achieve something with a miata. You have no idea how ignorant you sound with the "little baby 300hp miata tuning" statement. Everyone that comes from other platforms always acts the fool and a complete douchebag like you, cause they think they're just SOOOo much better than us.
I've tuned ID2000's on speed density. Have you? Personally? Come at me bro.
Uncle Scotty wouldn't last in here for more than 5 minutes. Go ahead and tell him to join. I dare you.
"Everyone that comes from other platforms always acts the fool and a complete douchebag like you, cause they think they're just SOOOo much better than us."
from other platforms?
I have had modified miatas (supercharged 02 se turtle) long before joining team broken ringland. Actually my first car was a miata. So no i dont really "come from another platform" I have just spent time in both. Like i said i have lerked here for years before i made a account because of the fighting pit that is this forum and now i will go back to lerking again.
Uncle Scotty would be a good fit for this forum i dont care what you think .
#53
at first i thought "Dang that's not a bad little turbo motor", then i saw the STI label.
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#55
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As you can see, the spool characteristics are pretty amazing for a turbo that size.
#56
I actually thought of posting that up earlier but was on my phone
But really: you're right. I even posted something along those lines in the very 1st handful of posts.
The only reason I even argued with that shortpenisbk guy is because he was using the stupidest arguments known to mankind.
But really: you're right. I even posted something along those lines in the very 1st handful of posts.
The only reason I even argued with that shortpenisbk guy is because he was using the stupidest arguments known to mankind.
#58
Twinscroll worth it?
So that was my thread on rx7club from a while ago.
The key with an even fire piston engine (I6, I4) is keeping the pulses separated, as has been mentioned already. This can be done with valve events or manifold and turbine housing design. On odd fire engines like normal cross plane v8's for example, a quick spool valve has more relative advantage because you can't get pulse separation without even firing order or unusual exhaust manifolds.
Evos were among the first piston gasoline vehicles to use twin scroll single turbos. The stronger pulses create more turbine power and allow more boost at low speed full load. This increases the torque you get when you are lugging at higher gears. So if you're in 5th gear at 1800rpm on the street you can actually make boost if it's sized right.
The twin scroll housings are more restrictive though and they increase turbine inlet pressure and residual gases at high speeds. This increases pumping work and knock sensitivity.
The thing people forget about are valve events. So on the newest Audi engines for example they run divided manifolds with undivided turbine housings, and then switch to late opening short duration exhaust cams to get a twin scroll pulsation effect. Then at higher speed they move to conventional valve events, and you don't have the normal high speed penalty you get from small exhaust cams or twin scroll manifolds.
See this thread for details (scroll down) http://www.thewolfweb.com/message_to...=617123&page=7
The key with an even fire piston engine (I6, I4) is keeping the pulses separated, as has been mentioned already. This can be done with valve events or manifold and turbine housing design. On odd fire engines like normal cross plane v8's for example, a quick spool valve has more relative advantage because you can't get pulse separation without even firing order or unusual exhaust manifolds.
Evos were among the first piston gasoline vehicles to use twin scroll single turbos. The stronger pulses create more turbine power and allow more boost at low speed full load. This increases the torque you get when you are lugging at higher gears. So if you're in 5th gear at 1800rpm on the street you can actually make boost if it's sized right.
The twin scroll housings are more restrictive though and they increase turbine inlet pressure and residual gases at high speeds. This increases pumping work and knock sensitivity.
The thing people forget about are valve events. So on the newest Audi engines for example they run divided manifolds with undivided turbine housings, and then switch to late opening short duration exhaust cams to get a twin scroll pulsation effect. Then at higher speed they move to conventional valve events, and you don't have the normal high speed penalty you get from small exhaust cams or twin scroll manifolds.
See this thread for details (scroll down) http://www.thewolfweb.com/message_to...=617123&page=7
#59
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subaru turbos spool slow and drop off.
everytimes I see an ST plot it makes me consider trading in the WRX for one more and more. But yeah, they have no guts up top, I'm sure if you raised the boost it would do nothing about 5K, and at least with a subby you can still push the top end a bit.
#60
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I currently rocking a TD04L. 212whp and 302wtq
Journal bearing
Needs a lot more timing after 5000rpm, but i need to make new detcans for listening to knock. Also needs to be a little more rich.
Journal bearing
Needs a lot more timing after 5000rpm, but i need to make new detcans for listening to knock. Also needs to be a little more rich.