Full-race's new toys
Jul 6, 2007, 04:44 AM
#76
sorry guys, geoff kindly asked me not to post up the pics since the final kit changed since the prototype pics were taken, if it's even better now i'm going to drop a load in my pants cuz the prototype pics were insane when i first saw them.
Jul 6, 2007, 05:03 AM
#77
Evolved Member
Join Date: Dec 2003
Location: UK
Posts: 1,074
Likes: 0
Received 0 Likes
on
0 Posts
The twin scroll honestly seems to have zero negatives, IMO. Well, provided you ignore the cost difference. More top end, faster spool, better mid range power, higher efficiency, amazing boost response. It's got it all. Here is a friends car that has seen a divided and undivided T4 setup on it within the last few months.
http://iwsti.com/blogs/007STI/
http://videos.streetfire.net/video/d...5701244f7f.htm
Here is a comparison between a divided and undivided GT42 setup. It is not a direct swap, as a few things were changed, but I think it shows the general idea of the benefits of the divided setups.
GT4294R setup (run 39):
Undivided manifold
2.45L (EJ25)
28.5 PSI
GT4202 setup (run 19)
2.6L
slightly shorter IC piping (thanks Geoff)
29 PSI
Faster spool with the BIGGER NON-BALL BEARING turbo then the undivided ball bearing turbo! Sure, it's a 2.45L vs. 2.6L, but I don't think that makes for 200HP gains in the mid range. I think the displacement and shorter piping likely just made up for the ball bearing center section and larger compressor on the spool up. The real gains, IMO came from the divided manifold setup. The curve is altered pretty drastically. Much better torque through the mid range, less torque loss above the torque peak. Smoother power delivery. On the street, the two I don't think the two can even be compared. On the divided setup, the turbo gets noisy at like 3000 RPMs. It screams and is just waiting for you to get on it at part throttle. Hit the gas and it comes on fast, hard and yet SMOOTH. The undivided setups seem to be completely gutless below about 4500 RPM then came on like a switch. It makes the car feel laggy and then violently fast. The divided setup is a whole different animal. There is instant boost, even if it's just 2-3 PSI, it's boost and it makes the car get to the real boost threshold nice and quick while ditching that switch like feel and perceived lag. The car doesn't feel as violent, but when you see the speedo passing 120mph like it's nothing, it puts it into perspective of just how fast the car is moving. Even if they get to maximum boost at the same RPM, the divided setup gets to full boost quicker in a time sense because of the boost it does get below the threshold and it is a night and day difference when you are driving the car. The video even shows it. If you've ever driven an undivided T4, you know that rolling into the throttle in 1st gear is about the strangest thing ever. Typically, it feels like a geo metro as the motor accelerates just fast enough to not let the turbo spool up. Not on this car. Hit the gas and before you know it, you are snapping off the rev limiter in 1st gear. Lag it on into 2nd and before you have time to think about it, you are back on the limiter. A normal undivided setup, toss a slow shift at it and half the gear is spent trying to get the turbo going. Toss it into third and you have the back end of an AWD car running 275 wide M/T drag radials breaking lose and scrambling for traction... Toss it without a quick shift on an undivided and you never get that nasty torque surge that caused all that tire spinning fun.
Geoff. Any chance you can hook up a good divided T4 GT3582R turbo? I want something to spool like a 50 trim yet destroy it on top end. Just a nice "stock like" feeling car with enough power to take down a new Z06. You know, something nice and simple.
http://iwsti.com/blogs/007STI/
http://videos.streetfire.net/video/d...5701244f7f.htm
Here is a comparison between a divided and undivided GT42 setup. It is not a direct swap, as a few things were changed, but I think it shows the general idea of the benefits of the divided setups.
GT4294R setup (run 39):
Undivided manifold
2.45L (EJ25)
28.5 PSI
GT4202 setup (run 19)
2.6L
slightly shorter IC piping (thanks Geoff)
29 PSI
Faster spool with the BIGGER NON-BALL BEARING turbo then the undivided ball bearing turbo! Sure, it's a 2.45L vs. 2.6L, but I don't think that makes for 200HP gains in the mid range. I think the displacement and shorter piping likely just made up for the ball bearing center section and larger compressor on the spool up. The real gains, IMO came from the divided manifold setup. The curve is altered pretty drastically. Much better torque through the mid range, less torque loss above the torque peak. Smoother power delivery. On the street, the two I don't think the two can even be compared. On the divided setup, the turbo gets noisy at like 3000 RPMs. It screams and is just waiting for you to get on it at part throttle. Hit the gas and it comes on fast, hard and yet SMOOTH. The undivided setups seem to be completely gutless below about 4500 RPM then came on like a switch. It makes the car feel laggy and then violently fast. The divided setup is a whole different animal. There is instant boost, even if it's just 2-3 PSI, it's boost and it makes the car get to the real boost threshold nice and quick while ditching that switch like feel and perceived lag. The car doesn't feel as violent, but when you see the speedo passing 120mph like it's nothing, it puts it into perspective of just how fast the car is moving. Even if they get to maximum boost at the same RPM, the divided setup gets to full boost quicker in a time sense because of the boost it does get below the threshold and it is a night and day difference when you are driving the car. The video even shows it. If you've ever driven an undivided T4, you know that rolling into the throttle in 1st gear is about the strangest thing ever. Typically, it feels like a geo metro as the motor accelerates just fast enough to not let the turbo spool up. Not on this car. Hit the gas and before you know it, you are snapping off the rev limiter in 1st gear. Lag it on into 2nd and before you have time to think about it, you are back on the limiter. A normal undivided setup, toss a slow shift at it and half the gear is spent trying to get the turbo going. Toss it into third and you have the back end of an AWD car running 275 wide M/T drag radials breaking lose and scrambling for traction... Toss it without a quick shift on an undivided and you never get that nasty torque surge that caused all that tire spinning fun.
Geoff. Any chance you can hook up a good divided T4 GT3582R turbo? I want something to spool like a 50 trim yet destroy it on top end. Just a nice "stock like" feeling car with enough power to take down a new Z06. You know, something nice and simple.
man thats a cool car!
any reason why he went no BB core??? also when is he getting full boost?? 5k ish???
LostSolVTEC, thats a bumer! but you have to understand why. i mean Buschur mentioned that they where testing a new HTA GT35r and tere was an up roar when they said they wheren't sure about pricing and avalibility.
Full Race you are doing it right by getting everything ready brfore you start showing off. this is where alot of companies go wrong, although they are just trying to be honnest and show people what they have found (they are car nuts like us all really). i have seen conpanies that have held back and not given dates or picks and it allways ends better that way.
thanks chris.
Jul 6, 2007, 06:06 AM
#78
LostSolVTEC, thats a bumer! but you have to understand why. i mean Buschur mentioned that they where testing a new HTA GT35r and tere was an up roar when they said they wheren't sure about pricing and avalibility.
Full Race you are doing it right by getting everything ready brfore you start showing off. this is where alot of companies go wrong, although they are just trying to be honnest and show people what they have found (they are car nuts like us all really). i have seen conpanies that have held back and not given dates or picks and it allways ends better that way.
thanks chris.
Full Race you are doing it right by getting everything ready brfore you start showing off. this is where alot of companies go wrong, although they are just trying to be honnest and show people what they have found (they are car nuts like us all really). i have seen conpanies that have held back and not given dates or picks and it allways ends better that way.
thanks chris.
Jul 6, 2007, 10:32 AM
#81
By 5k on the street in any gear, you are holding onto the roll cage for dear life. I don't know if it's at full boost by then, but in the lower gears, it's breaking traction by then.
that manifold looks REALLY good.
Jul 9, 2007, 05:59 PM
#86
hey guys -- thanks for all the discussion. we've been SUPER busy lately, so im sorry i havent been able to get on here as much in the past few days
Hi Reine -- reread the description below, this is exactly what you could expect
and of course what ted wrote...
thats an accurate description. For a given throttle position the turbine wheel (and compressor wheel, correspondingly) are both spinning faster. For this to occur it simply means the system is more efficient: more exhaust energy is being converted into mechanical energy (spinning the turbo)
i think that is an accurate statement
unless there was a reallly good reason, twinscroll performance dwarfs the performance of a standard single scroll t3 or t4. its no comparison. we have worked really hard redesigning every turbokit we manufacture to be twinscroll. Single scroll just doesnt compare, it feels boring
Jun is a good guy, his car came out sick! A 650whp street honda is no joke, the top end on that setup is just so strong. thanks alot for the support!
Unfortunately the T4 gt35Rs are almost impossible to get anymore. Additionally, the turbine inlets were undersized from true t4. it was a very strange concoction. The turbonetics F1-35R is supposed to fill that void. here is a pic comparing the T4 GT35R to the Turbonetics F1-35R
The best comparison is of course to have a single scroll setup, then change to a twinscroll (i think this is what Ted B did). This way you REALLY understand the difference. Unfortunately this is honestly a waste of money and time, so the best thing to do is to simply get a twinscroll setup in the first place...
thanks alot chris. We hope to change some minds about Full-Race's evo kits. alot of people have had some not too good things to say about our kits, so we're working to set the record straight
the kits are in production now. If you are interested in one the best thing to do is to call the sales office and speak with Lloyd or Aaron (sales managers). They can give you lead times and pricing. any tech questions i am the person to ask
the kit has been redesigned to provide much more clearance from the rad than our older kits. That was our #1 complaint, so we obviously wanted to change that. heres a pic showing how much extra clearance we have over a PWR radiator
thanks, it was REALLY hard to design
we're working on having a 30R and a 40R twinscroll kit ready for the event
thanks for all the discussion
On the street, the two I don't think the two can even be compared. On the divided setup, the turbo gets noisy at like 3000 RPMs. It screams and is just waiting for you to get on it at part throttle. Hit the gas and it comes on fast, hard and yet SMOOTH. The undivided setups seem to be completely gutless below about 4500 RPM then came on like a switch. It makes the car feel laggy and then violently fast. The divided setup is a whole different animal. There is instant boost, even if it's just 2-3 PSI, it's boost and it makes the car get to the real boost threshold nice and quick while ditching that switch like feel and perceived lag. The car doesn't feel as violent, but when you see the speedo passing 120mph like it's nothing, it puts it into perspective of just how fast the car is moving. Even if they get to maximum boost at the same RPM, the divided setup gets to full boost quicker in a time sense because of the boost it does get below the threshold and it is a night and day difference when you are driving the car. The video even shows it. If you've ever driven an undivided T4, you know that rolling into the throttle in 1st gear is about the strangest thing ever. Typically, it feels like a geo metro as the motor accelerates just fast enough to not let the turbo spool up. Not on this car. Hit the gas and before you know it, you are snapping off the rev limiter in 1st gear. Lag it on into 2nd and before you have time to think about it, you are back on the limiter. A normal undivided setup, toss a slow shift at it and half the gear is spent trying to get the turbo going.
what is most noticeable is the fact that the divided setup has the turbine wheel spinning faster at ALL throttle positions. What this does is make the divided setup much more responsive to changes in throttle position (transient response), which makes the car feel torquier and quicker to jump. This is not something that can be measured on a static, WOT dyno pull, but it is darn sure felt by whomever is driving it.
Full Race you are doing it right by getting everything ready brfore you start showing off. this is where alot of companies go wrong, although they are just trying to be honnest and show people what they have found (they are car nuts like us all really). i have seen conpanies that have held back and not given dates or picks and it allways ends better that way.
the kits are in production now. If you are interested in one the best thing to do is to call the sales office and speak with Lloyd or Aaron (sales managers). They can give you lead times and pricing. any tech questions i am the person to ask
thanks, it was REALLY hard to design
thanks for all the discussion
Last edited by Geoff Raicer; Jul 9, 2007 at 06:01 PM.
Jul 9, 2007, 07:54 PM
#89
edit: if you reallllllllly wanted a twinscroll 50 trim, ITS can do it for you, but imo it wont perform as well as the 30R, and it would likely cost the same
Last edited by Geoff Raicer; Jul 9, 2007 at 07:57 PM.
