twin scroll hype?
#77
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EvoDan's engine compartment is enviably excellent inspite of the Status Quo Ante, MAF, 4">3"<4", restrictive device. All in all, impeccable actually.
Last edited by sparky; Oct 5, 2007 at 06:17 PM.
#79
hmmm, all I could point out is on a twin scroll turbine housing, it's very hard for the designers to come out with a pair of near perfect volute. so you do lose a few points of turbine efficiency, which is ok for a street car...
#81
Interesting point. But looking at mitsubishi housing its quite clear there was no attempt to keep the two volute equal in size. The a/r on 2+3 is way smaller than the a/r on 1+4. There is way more a few points of efficiency lost with scrolls like that. I would of at least expected cyylinders 2+3 to get the larger scroll since those cylinders tend to run hotter than 1+4.
#82
Jeff, you are the only one who attempts to address my observations with some technical support. But now I see you are jumping on the insult bandwagon to prove your points.
You have yet to address my observation that it is pertinent to get the a/r correct on a setup and twin scroll offers only one or two choices of A/R that may not be ideal for the setup.
You have yet to address my observation that it is pertinent to get the a/r correct on a setup and twin scroll offers only one or two choices of A/R that may not be ideal for the setup.
#83
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no "insult bandwagon jumping" going on here...
does a/r matter in twinscroll? HELL YES!
does a/r matter in singlescroll? HELL YES!
is it pertinent to get the correct a/r setup on a single scroll or a twinscroll? absolutely!!!
are twinscroll housings ultra-rare and hard to find? some yes, some no. some used to be and are now becoming much more common (ie T3 1.06a/r for gt30R and gt35R). on the other hand, borg warner doesnt even make single scroll housings.
there is so much misinformation in this thread, im not going to take the time to clean it all up (sorry its friday night)
does a/r matter in twinscroll? HELL YES!
does a/r matter in singlescroll? HELL YES!
is it pertinent to get the correct a/r setup on a single scroll or a twinscroll? absolutely!!!
are twinscroll housings ultra-rare and hard to find? some yes, some no. some used to be and are now becoming much more common (ie T3 1.06a/r for gt30R and gt35R). on the other hand, borg warner doesnt even make single scroll housings.
there is so much misinformation in this thread, im not going to take the time to clean it all up (sorry its friday night)
#87
Well let us all just breathe... and wait for the twin-scroll GT40 to make 800 hp at the crank and spool better than a GT35R as I believe Geoff has implied in previous threads.
I think everyone in this thread recognizes the benefits and some of the theory in twin scroll. However, naturally a lot of us are skeptical when claims like above are made because it is such a gigantic leap in the status quo of performance.
I think everyone in this thread recognizes the benefits and some of the theory in twin scroll. However, naturally a lot of us are skeptical when claims like above are made because it is such a gigantic leap in the status quo of performance.
#89
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SWEET! I see an aftermarket exhaust manifold in classic black and white
Seriously though... this is the most civil, mature debate I've seen in a VERY long time. Please keep it this way guys. There are some very knowledgeable people involved here with varying opinions on personal experiences. I've personally yet to be swayed either way... because some people seem to be arguing two different views of the same fight. I believe both are right in there specific applications. When you've seen a mere spark plug change make a 100whp difference, it comes into perspective for you. Then again that's 4 more cylinders and a little over 4 times the displacement. However, I think the arguing parties understand what I'm talking about.
Wish some of the vendors could have discussions this civilly!
Seriously though... this is the most civil, mature debate I've seen in a VERY long time. Please keep it this way guys. There are some very knowledgeable people involved here with varying opinions on personal experiences. I've personally yet to be swayed either way... because some people seem to be arguing two different views of the same fight. I believe both are right in there specific applications. When you've seen a mere spark plug change make a 100whp difference, it comes into perspective for you. Then again that's 4 more cylinders and a little over 4 times the displacement. However, I think the arguing parties understand what I'm talking about.
Wish some of the vendors could have discussions this civilly!
Full Race Manifold
Full Race Dump Tube
Gt3037s
Tial 44mm Wastegate
780cc Injectors
Force Performance Intake arm
About to add FR Vertical Intercoler to the setup, and put down 400whp!!
#90
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When I was looking at the mitsubishi housing, it didn't seem like the scroll area was smaller. It seemed like the nozzle was actually just shorter but the bulk flow areas were the same.
Something of interest to me on the Mitsubishi housings is that the seemingly smaller scroll area is closer to the turbine housing exducer. Is there a chance that some CFD work on Mitsubishi's part has shown that maybe the turbine wheel offers less restriction to the gases in the second scroll and the smaller scroll area is an attempt to equalize the pressure drops through the housings?
I think I've seen some pictures of an old 80's turbo F1 motor and they were using twin scroll setups and the turbine housings looked like the Mitsubishi housing. Maybe it was a CART motor? It was a 180 degree V8, which from my understanding is 2 inline 4-cylinders put together and I would assume so that they got the full timing benefits of the twin scroll manifold.
Something of interest to me on the Mitsubishi housings is that the seemingly smaller scroll area is closer to the turbine housing exducer. Is there a chance that some CFD work on Mitsubishi's part has shown that maybe the turbine wheel offers less restriction to the gases in the second scroll and the smaller scroll area is an attempt to equalize the pressure drops through the housings?
I think I've seen some pictures of an old 80's turbo F1 motor and they were using twin scroll setups and the turbine housings looked like the Mitsubishi housing. Maybe it was a CART motor? It was a 180 degree V8, which from my understanding is 2 inline 4-cylinders put together and I would assume so that they got the full timing benefits of the twin scroll manifold.