twin scroll hype?
Oct 1, 2007, 10:36 PM
#46
sorry im late to the party, i havent had much time lately to get on the forums.
94AWD -- i know scott, and i know he doesnt believe in twinscroll. Also, I think its great that you question the experts; thinking for yourself is truly the only way to REALLY learn whats going on.
The questions and points you have are all valid. Before you come to any conclusions or spend any money, just give it some time. We are going to be around for a while, and there will be a lot of tests/results in the near future. There is a lot to learn!!
94AWD -- i know scott, and i know he doesnt believe in twinscroll. Also, I think its great that you question the experts; thinking for yourself is truly the only way to REALLY learn whats going on.
The questions and points you have are all valid. Before you come to any conclusions or spend any money, just give it some time. We are going to be around for a while, and there will be a lot of tests/results in the near future. There is a lot to learn!!
Oct 2, 2007, 12:24 AM
#47
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I have personally been waiting for your TS results ON AN EVO for months. All I see is a Full Race add on evom that claims a TS 40r to produce 780whp and claims how a TS setup "feels" so much more responsive than a 35r. Well, with the 780whp add on top of the page you should be able to run 9's on a built Evo. Until we see trap times in the 140's and REAL #S IT'S ALL HYPE IMHO. You don't get a 40r in your Evo to go to McDonalds and get awesome spool and "feel", you get a FR TS 40r to run 9's and get better spool than a pt67r. Still waiting for the #'s and trap times.
Oct 2, 2007, 02:11 AM
#48
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I strongly believe there is a very straightforward reasons why a few of these Garrett GT BB turbos are not easily optimised as twin scroll turbos .
I'll look directly at the turbos themselves because if the manifold is not designed properly nothing turbo wise will change the - result .
Garretts GT28XXR's , GT30xxR's , and the GT3582R (inc HKS spec GT3240R) were not specifically designed to be twin scroll turbos . The one thing that hits you right between the eyes when you look at twin scroll "T" series turbos and large frame Garrett GT BB twin scroll turbos is the wheel trims .
Its very obvious that they've erred towards slightly larger turbines in smaller trims and while the compressor diametre is not particularly huge compared to the turbine their trims are often smaller than the same family wheel used in a petrol performance small frame GT BB turbo . Take for example a small frame GT BB 3582R , 68mm 84T turbine and an 82mm 56T compressor . In twin scroll form Garretts truck diesel turbo uses a very similar spec turbine but with the 76mm 56T comp from the GT3076R . So we've gone down a comp family size for a very similar turbine though the housings are pretty huge GT40 type items , 1.17 A/R TS on the exhaust and a rather huge 0.65 A/R comp housing . In this example the trims haven't changed but the compressor has .
I'll jump up to the large frame GT BB's and look at the GT37xxR's . From memory the BB type GT37 turbine is 72.5mm 78T and that has to be better than the GT35's 68mm 84T . The comps are 82mm 50T (St 1 C117 comp) , 82mm 56T (St 2 same comp as GT3076R) , 88mm 52T (St 3 C117 comp same as GT4088R) . The GT4088R uses a 77mm 78T turbine and an 88mm 52T comp .
Actually the large frame bush bearing GT turbos tend to lean towards smaller comp trims ie GT4082 (77mm 73T turb plus 82mm 50T comp) . The GT3776 and GT3782 both use 52 rather than 56T compressors .
I think the bottom line is that until we see the GT30 and GT35 petrol spec BB turbines in trims smaller than 84T they won't be the best thing for a optimised twin scroll turbo . The thing to remember is that petrol spec GT30 and GT35 turbines were designed to flow a lot of gas and they do but its partly the large ie 84 trim size that allows them to do it .
A personal theory is that a correctly sized twin scroll turbine housing causes exhaust gas TEMPERATURE and pressure to drop so it starts to act a little like a diesel except the EGT would be higher than a diesel . I believe the longer torque arms of bigish diametre turbines can work well on petrol fired engines and when combined with a smaller but adequate trim size the turbine wins the three way war - by that I mean
1) Good shaft power from large radius torque arms (blades) .
2) Low restriction to exhaust flow because of a greater turbine/nozzle diametre .
3) Acceptable response tuned by exducer (trim) size .
Untill turbine specs change about the best you can probably do is is use turbos like the GT3071R or if Garrett chose to make it a GT3576R because of their enhanced exhaust flow vs adequate airflow abilities .
I also think heads and cams need to alter because the pressure balance across the engine and hence its state of tune changes in twin scroll form .
Another 2c spent , cheers A .
I'll look directly at the turbos themselves because if the manifold is not designed properly nothing turbo wise will change the - result .
Garretts GT28XXR's , GT30xxR's , and the GT3582R (inc HKS spec GT3240R) were not specifically designed to be twin scroll turbos . The one thing that hits you right between the eyes when you look at twin scroll "T" series turbos and large frame Garrett GT BB twin scroll turbos is the wheel trims .
Its very obvious that they've erred towards slightly larger turbines in smaller trims and while the compressor diametre is not particularly huge compared to the turbine their trims are often smaller than the same family wheel used in a petrol performance small frame GT BB turbo . Take for example a small frame GT BB 3582R , 68mm 84T turbine and an 82mm 56T compressor . In twin scroll form Garretts truck diesel turbo uses a very similar spec turbine but with the 76mm 56T comp from the GT3076R . So we've gone down a comp family size for a very similar turbine though the housings are pretty huge GT40 type items , 1.17 A/R TS on the exhaust and a rather huge 0.65 A/R comp housing . In this example the trims haven't changed but the compressor has .
I'll jump up to the large frame GT BB's and look at the GT37xxR's . From memory the BB type GT37 turbine is 72.5mm 78T and that has to be better than the GT35's 68mm 84T . The comps are 82mm 50T (St 1 C117 comp) , 82mm 56T (St 2 same comp as GT3076R) , 88mm 52T (St 3 C117 comp same as GT4088R) . The GT4088R uses a 77mm 78T turbine and an 88mm 52T comp .
Actually the large frame bush bearing GT turbos tend to lean towards smaller comp trims ie GT4082 (77mm 73T turb plus 82mm 50T comp) . The GT3776 and GT3782 both use 52 rather than 56T compressors .
I think the bottom line is that until we see the GT30 and GT35 petrol spec BB turbines in trims smaller than 84T they won't be the best thing for a optimised twin scroll turbo . The thing to remember is that petrol spec GT30 and GT35 turbines were designed to flow a lot of gas and they do but its partly the large ie 84 trim size that allows them to do it .
A personal theory is that a correctly sized twin scroll turbine housing causes exhaust gas TEMPERATURE and pressure to drop so it starts to act a little like a diesel except the EGT would be higher than a diesel . I believe the longer torque arms of bigish diametre turbines can work well on petrol fired engines and when combined with a smaller but adequate trim size the turbine wins the three way war - by that I mean
1) Good shaft power from large radius torque arms (blades) .
2) Low restriction to exhaust flow because of a greater turbine/nozzle diametre .
3) Acceptable response tuned by exducer (trim) size .
Untill turbine specs change about the best you can probably do is is use turbos like the GT3071R or if Garrett chose to make it a GT3576R because of their enhanced exhaust flow vs adequate airflow abilities .
I also think heads and cams need to alter because the pressure balance across the engine and hence its state of tune changes in twin scroll form .
Another 2c spent , cheers A .
Oct 2, 2007, 05:24 AM
#49
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I ran out of time before so the last bit I wanted to add .
I think its only possible to tune a turbines performance so far with housing A/R alone , we don't have much say in what turbine trim sizes Garretts prepared to give us but I know that they know the answers .
I imagine some of you would have seen Garretts latest catalog ie the one that shows their TR30R competition turbochargers . Its very interesting to look at the turbine trims and compressor options as well . You won't find their NS111 60mm turbine offered in 84 trim though from memory they do them in 73 and 76 trims - I'll check tomorrow . In case you were wondering these are not TS turbos but they are very much aimed at making a lot of torque over a lowish rev range engine (inlet air restrictors) so the turbine trim size is significant .
Jumping to the large frame end of the Garrett range , ever wonder why the HKS spec Garrett T51R KAI/SPL is more responsive than the GT4294R/4202R ? HKS want you to think that their version is slicker than teflon and has sexier housings . The fact of the matter is that theirs has a 76 trim dinosaur T51 turbine where the 42R's use a more modern GT42UHP turbine - in 84 trim ....
The sad fact of life is that the older turbine in the preferable trim is more responsive .
When we can get suitable TS turbine housings and the right turbine trim sizes it won't be real difficult to prove the TS systems worth , its important to remember that the exhaust tract starts at the valves and ends at the atmosphere so everything in between has to work together to give the best results .
Nite all , A .
I think its only possible to tune a turbines performance so far with housing A/R alone , we don't have much say in what turbine trim sizes Garretts prepared to give us but I know that they know the answers .
I imagine some of you would have seen Garretts latest catalog ie the one that shows their TR30R competition turbochargers . Its very interesting to look at the turbine trims and compressor options as well . You won't find their NS111 60mm turbine offered in 84 trim though from memory they do them in 73 and 76 trims - I'll check tomorrow . In case you were wondering these are not TS turbos but they are very much aimed at making a lot of torque over a lowish rev range engine (inlet air restrictors) so the turbine trim size is significant .
Jumping to the large frame end of the Garrett range , ever wonder why the HKS spec Garrett T51R KAI/SPL is more responsive than the GT4294R/4202R ? HKS want you to think that their version is slicker than teflon and has sexier housings . The fact of the matter is that theirs has a 76 trim dinosaur T51 turbine where the 42R's use a more modern GT42UHP turbine - in 84 trim ....
The sad fact of life is that the older turbine in the preferable trim is more responsive .
When we can get suitable TS turbine housings and the right turbine trim sizes it won't be real difficult to prove the TS systems worth , its important to remember that the exhaust tract starts at the valves and ends at the atmosphere so everything in between has to work together to give the best results .
Nite all , A .
Oct 2, 2007, 07:33 AM
#50
sorry im late to the party, i havent had much time lately to get on the forums.
94AWD -- i know scott, and i know he doesnt believe in twinscroll. Also, I think its great that you question the experts; thinking for yourself is truly the only way to REALLY learn whats going on.
The questions and points you have are all valid. Before you come to any conclusions or spend any money, just give it some time. We are going to be around for a while, and there will be a lot of tests/results in the near future. There is a lot to learn!!
94AWD -- i know scott, and i know he doesnt believe in twinscroll. Also, I think its great that you question the experts; thinking for yourself is truly the only way to REALLY learn whats going on.
The questions and points you have are all valid. Before you come to any conclusions or spend any money, just give it some time. We are going to be around for a while, and there will be a lot of tests/results in the near future. There is a lot to learn!!
The current problem with twin scroll is this. Getting the right A/R on the car is still crucial. In my 57trim example the right housing was a 63. If you used a 48 or 82 you did not come close to maxing the performance of that turbo. If I were going to build a gt30 car I would build a header with a t25 inlet. That way I could use HKS exhaust housings that come in proper increments, .61 .73 .87 .1.01 1.12. Now when you switch to twin scroll the situation is no different. You still got to get the A/R correct. Problem is there may only be one housing A/R available. To say that you are getting the right A/R for you application with that one A/R available is pretty dumb from my standpoint. I dont second guess for a second that the .63 open in my original post out performed the TS 78 on that particular car. If you are anyone else dont understand that it is a shame.
Carry on with your research. I am watching.
Oct 2, 2007, 09:02 AM
#51
Vette hits first stage from go, not enough. second race Vette gets the hit so there is no excuses, hits first stage, then 2nd and when 2nd stage came on it was traction loss right to the rev limiter misses the next gear and shuts down.
http://www.mafia-motorsports.com/forums/videos.php ~click vid beneath the the Cortney-Blond chick
Last edited by Migsubishi; Oct 2, 2007 at 09:12 AM.
Oct 2, 2007, 09:32 AM
#52
[quote=94AWDcoupe;4806370] If any of the haters took a ride in any of my cars I promise you their attitude would change. [quote]
First off no one is hating on you or your car. I honestly think your car pretty bad ***, but you need to get rid of that chip on your shoulder. No one here makes post that say " 94AWDcoupe... Hype?" . If anyone is hating here it seems to be you. From the beginning , when I would post up my TS dyno graphs showing comparitive numbers on different vehicles you would alway say things like " that's not impressive or graphs are useless". You seemed to always show up in my post to try and disclaim TS. I don't get it.
I don't think anyone can deny that you car is fast. 2500lbs, 2.4L 30+psi boost, methanol, and high 500whp. Anything would be fast with that power to weight ratio. All of your talk about your crazy spool and super response with an open scroll is most likely due to you displacement and 900lbs less wieght than us Evo guys deal with. You tend to try and compare your set up to the few 2.0L guys running the TS. which there is no comparison.
Again I think if there is any "hating" on you it's because how you approach discussions here. Telling people that they are dead wrong and that their reasoning is stupid is not how to get respect for one's views. I don't understand why you can't just let the TS people have there fun and try something different without you trying to discredit it. People are gonna do what they want in the end.
First off no one is hating on you or your car. I honestly think your car pretty bad ***, but you need to get rid of that chip on your shoulder. No one here makes post that say " 94AWDcoupe... Hype?" . If anyone is hating here it seems to be you. From the beginning , when I would post up my TS dyno graphs showing comparitive numbers on different vehicles you would alway say things like " that's not impressive or graphs are useless". You seemed to always show up in my post to try and disclaim TS. I don't get it.
I don't think anyone can deny that you car is fast. 2500lbs, 2.4L 30+psi boost, methanol, and high 500whp. Anything would be fast with that power to weight ratio. All of your talk about your crazy spool and super response with an open scroll is most likely due to you displacement and 900lbs less wieght than us Evo guys deal with. You tend to try and compare your set up to the few 2.0L guys running the TS. which there is no comparison.
Again I think if there is any "hating" on you it's because how you approach discussions here. Telling people that they are dead wrong and that their reasoning is stupid is not how to get respect for one's views. I don't understand why you can't just let the TS people have there fun and try something different without you trying to discredit it. People are gonna do what they want in the end.
Oct 2, 2007, 09:56 AM
#53
I don't think anyone can deny that you car is fast. 2500lbs, 2.4L 30+psi boost, methanol, and high 500whp. Anything would be fast with that power to weight ratio. All of your talk about your crazy spool and super response with an open scroll is most likely due to you displacement and 900lbs less wieght than us Evo guys deal with. You tend to try and compare your set up to the few 2.0L guys running the TS. which there is no comparison.
Again I think if there is any "hating" on you it's because how you approach discussions here. Telling people that they are dead wrong and that their reasoning is stupid is not how to get respect for one's views. I don't understand why you can't just let the TS people have there fun and try something different without you trying to discredit it. People are gonna do what they want in the end.
He is not just refering to that car, he has a hella fast Evo 1 on a 2.0 thats just a little slower than is mirage, just doesn't have that breath taking torque but it gets down with the best of them. He also has an Evo 9 , so he is very well versed in these cars. A chip on his shoulder, I wouldn't say that, I would just say he is pretty arrogant and big headed. For the wealth of knowlege he has who wouldn't be. Look at Dave B, He responds to people in the same way on the boards.
Don't take the way he posts as personal attacks, its just the way he is and has always been. I even but heads with the guy due to his arrogance and ego, yet our kids play together and we are personal friends. Just saying he is not angry and don't take anything he says to heart man.
Lots of good stuff though you all sound like you know what your talking about, I will just keep reading, I have nothing more to say for that this is over my head
Last edited by Migsubishi; Oct 2, 2007 at 09:59 AM.
Oct 2, 2007, 12:09 PM
#54
The thing I don't get... is Full-Race is selling a lot of these kits already.
Honestly, how hard would it be to offer someone a kit at discount, if they allowed some back to back testing. Full-Race single scroll GT35R versus twin? It seems to me this would cost Full-Race practically nothing. Just give the customer the kit that performed better at the end of the test at a bit of a discount.
Honestly, how hard would it be to offer someone a kit at discount, if they allowed some back to back testing. Full-Race single scroll GT35R versus twin? It seems to me this would cost Full-Race practically nothing. Just give the customer the kit that performed better at the end of the test at a bit of a discount.
Oct 2, 2007, 12:17 PM
#55
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Oct 4, 2007, 05:08 PM
#56
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Ok , i'm no technical guru & I have had very limited experience in cars anyway due to me living in a very remote area.
I own a 01 evo 7 , pretty modified , and i'm certainly going to get a FR ts 35r or 40r setup. Thats for the introduction.
As I said , I live in a remote area ( new caledonia if you want to look that up on a map , aim for a tiny spot between australia and new zealand ) . There are no tuners here , or even proper mechanics for that matter. When I had to tune my car I had to fly a guy from australia to do the job . I'm using a Motec M800 ecu , and the guy who takes care of the tuning and advises me is a traveling tuner , who worked for motec 11 years, in ecu devellopment and troubleshooting before runing his own business. When speaking about that TS hype with him and my possible turbo kit choices , he had that answer :
" TS will always be superior to SS in real life, there's no need to argue about it , if someone argues about it shoot him. No discussion, 1 bullet."
Everybody has a right to have its opinion, and I respect it, just thought i'd share that here...
I own a 01 evo 7 , pretty modified , and i'm certainly going to get a FR ts 35r or 40r setup. Thats for the introduction.
As I said , I live in a remote area ( new caledonia if you want to look that up on a map , aim for a tiny spot between australia and new zealand ) . There are no tuners here , or even proper mechanics for that matter. When I had to tune my car I had to fly a guy from australia to do the job . I'm using a Motec M800 ecu , and the guy who takes care of the tuning and advises me is a traveling tuner , who worked for motec 11 years, in ecu devellopment and troubleshooting before runing his own business. When speaking about that TS hype with him and my possible turbo kit choices , he had that answer :
" TS will always be superior to SS in real life, there's no need to argue about it , if someone argues about it shoot him. No discussion, 1 bullet."
Everybody has a right to have its opinion, and I respect it, just thought i'd share that here...
Oct 4, 2007, 05:13 PM
#57
well i have a 30r ts kit. and LOVE it.
my last logs showed 25psi at 3840 rpm's it held 25psi at 8100 rpm. useing a jdm map sensor and evoscan.
i went to the track but i suck at launching the car. 11.5 at 124 with a 1.89 60 foot.
i made 5 passes. three 11.5s one 11.6 and a missed gear so i shut it down. 19.1 or somthing. all 1.89 to 1.98 60s
car is down right now
so no more fun. hoping to have it back up for sunday for more track time.
my last logs showed 25psi at 3840 rpm's it held 25psi at 8100 rpm. useing a jdm map sensor and evoscan.
i went to the track but i suck at launching the car. 11.5 at 124 with a 1.89 60 foot.
i made 5 passes. three 11.5s one 11.6 and a missed gear so i shut it down. 19.1 or somthing. all 1.89 to 1.98 60s
car is down right now
so no more fun. hoping to have it back up for sunday for more track time.
Oct 4, 2007, 05:22 PM
#58
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well i have a 30r ts kit. and LOVE it.
my last logs showed 25psi at 3840 rpm's it held 25psi at 8100 rpm. useing a jdm map sensor and evoscan.
i went to the track but i suck at launching the car. 11.5 at 124 with a 1.89 60 foot.
i made 5 passes. three 11.5s one 11.6 and a missed gear so i shut it down. 19.1 or somthing. all 1.89 to 1.98 60s
car is down right now so no more fun. hoping to have it back up for sunday for more track time.
my last logs showed 25psi at 3840 rpm's it held 25psi at 8100 rpm. useing a jdm map sensor and evoscan.
i went to the track but i suck at launching the car. 11.5 at 124 with a 1.89 60 foot.
i made 5 passes. three 11.5s one 11.6 and a missed gear so i shut it down. 19.1 or somthing. all 1.89 to 1.98 60s
car is down right now
so no more fun. hoping to have it back up for sunday for more track time.
