rcdash v2.0
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From: Chapel Hill, NC
My 2004 5AT G35 coupe was built a while back with 24k on the original motor at Forged Performance with a basic built short block with JWT S2 cams and a 700bb JWT kit and a built 5AT from GTM. I've been enjoying the car for a few years now at the ~500 whp level. It was sorely in need of some maintenance that I had no desire to dig into myself (e.g. changing out the oil return hoses on those turbos located way up high in the engine bay). I also wanted to see if Hal could convince Haltech AUS to get the new Plugin Pro Haltech unit working on my 5AT so I thought I'd give Dynosty a shot at looking after the car this past winter and dropped the car off on Feb 1st. To keep a long story short, the new GTX turbos had just come out and I asked Hal to see if he could adapt it for use on my JWT kit while the motor was down. The compressor map looked like an impressive improvement over their standard counterparts (comparing 700bb turbo to GTX2867, with the line mapping airflow to reach 600 whp):

Well I ended up getting the turbos to "try" and one thing led to another and I ended up with a few upgrades:
GTX2867 turbos with Tial v-band 0.86 A/R cast stainless turbine housings.

SFR 321 stainless headers with burns collectors.

Some Dynosty fabrication at work.



Here was a base line dyno when the car arrived (18-19 psi on 93/meth; tough day on Hal's dyno for my car):

Here was the best run after tuning with the new kit (18-19 psi on 93):

With the free flowing exhaust the 1 bar springs ended up producing a pretty high WG power level. Unfortunately the 5AT cannot hold this power consistently on Hal's dyno - and power fluctuates between 530-580 whp depending on transmission slip at high rpms. So this is where we decided to leave it for now (no boost control). I will be needing to consider other transmission options to turn the boost up, and these turbos are efficient through 30 psi
. 6MT vs something else? We shall see... For now, the car is a blast to drive and I'm back to enjoying it for awhile.
Many thanks to Hal, Dustin, and the crew at Dynosty for a job well done. How would I rate the experience? They get an A for customer service, A for integrity, A for knowledge/expertise, A for workmanship/quality. Only ***** in the armor is that I'd give them a B for meeting time expectations as I ended up missing ZdayZ, though I was warned that that might happen. It was a complex build (details like fuel voltage regulation, oil return, etc I haven't mentioned among other nice touches) but still I was given hope it would be done in time. They did work hard to try to meet that deadline but they would not release the car half done or untested, and well, the result is what it is. Bottom line, they have earned my trust and my future business.
The car has been tuned to perfection. It starts and drives perfectly - no hiccups, no hesitation - just smooth power to redline. I cannot feel any transmission issues while on the road. It pulls much better up top than it used to, spools just about as quickly, and has so much room to grow. Happy to answer any questions. Later guys - happy boosting...

PS. I'll be having a few parts for sale in marketplace for anyone looking to piece together a 700bb turbo kit for very cheap
Old kit now boxed up and ready to ship, click here!

Well I ended up getting the turbos to "try" and one thing led to another and I ended up with a few upgrades:
GTX2867 turbos with Tial v-band 0.86 A/R cast stainless turbine housings.

SFR 321 stainless headers with burns collectors.

Some Dynosty fabrication at work.



Here was a base line dyno when the car arrived (18-19 psi on 93/meth; tough day on Hal's dyno for my car):

Here was the best run after tuning with the new kit (18-19 psi on 93):

With the free flowing exhaust the 1 bar springs ended up producing a pretty high WG power level. Unfortunately the 5AT cannot hold this power consistently on Hal's dyno - and power fluctuates between 530-580 whp depending on transmission slip at high rpms. So this is where we decided to leave it for now (no boost control). I will be needing to consider other transmission options to turn the boost up, and these turbos are efficient through 30 psi
Many thanks to Hal, Dustin, and the crew at Dynosty for a job well done. How would I rate the experience? They get an A for customer service, A for integrity, A for knowledge/expertise, A for workmanship/quality. Only ***** in the armor is that I'd give them a B for meeting time expectations as I ended up missing ZdayZ, though I was warned that that might happen. It was a complex build (details like fuel voltage regulation, oil return, etc I haven't mentioned among other nice touches) but still I was given hope it would be done in time. They did work hard to try to meet that deadline but they would not release the car half done or untested, and well, the result is what it is. Bottom line, they have earned my trust and my future business.
The car has been tuned to perfection. It starts and drives perfectly - no hiccups, no hesitation - just smooth power to redline. I cannot feel any transmission issues while on the road. It pulls much better up top than it used to, spools just about as quickly, and has so much room to grow. Happy to answer any questions. Later guys - happy boosting...

PS. I'll be having a few parts for sale in marketplace for anyone looking to piece together a 700bb turbo kit for very cheap
Old kit now boxed up and ready to ship, click here!
Last edited by rcdash; Aug 23, 2012 at 06:01 PM.
sick! awesome upgrade Raj. What is the word on that new stand alone or are you going to jump ship to the 6mt? You could probably do t400 as well if you want that sick constant boost between gears though.
Looks like your peak tq increased just a little but the top end HP went way up due to the free flow of those turbos.
You're a picky guy on tunes so when you say it's smooth it must be VERY smooth.
Looks like your peak tq increased just a little but the top end HP went way up due to the free flow of those turbos.
You're a picky guy on tunes so when you say it's smooth it must be VERY smooth.
Very nice upgrade, and improvement. It is nice to see solid proof that the tubilar manifolds are superior to the log style with a properly sized turbine housing.
Did you retain the JWT FMIC and IC pluming? I always thought the cold side of the kit was a weak point.
Did you retain the JWT FMIC and IC pluming? I always thought the cold side of the kit was a weak point.
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From: Chapel Hill, NC
Thanks guys.
No I also thought the cold side might be holding the 700bb turbos back a bit so I had the kit modified for dual intakes and a vertical flow intercooler, but did not realize much gains. Those turbos are just out of steam at 18 psi. More boost gives a bit more midrange torque but does nothing for peak power. You can see on the compressor chart that there would have been little hope of hitting 600 whp with them. They are great turbos up to 500-550 whp max.
I was expecting the GTX turbos to provide a better top end, but was pleasantly surprised with the retained spool up characteristics. I was worried the tubular manifolds + larger compressor wheel would have introduced significant lag.
Hal spent an unbelievable amount of time on the dyno and on the road with the car. I am very grateful for his attention to detail. I also learned a great many new things with the way he went about solving little issues here and there, very impressive, and very considerate of him to keep me in the loop considering he is one busy guy!
Very nice upgrade, and improvement. It is nice to see solid proof that the tubilar manifolds are superior to the log style with a properly sized turbine housing.
Did you retain the JWT FMIC and IC pluming? I always thought the cold side of the kit was a weak point.
Did you retain the JWT FMIC and IC pluming? I always thought the cold side of the kit was a weak point.
I was expecting the GTX turbos to provide a better top end, but was pleasantly surprised with the retained spool up characteristics. I was worried the tubular manifolds + larger compressor wheel would have introduced significant lag.
sick! awesome upgrade Raj. What is the word on that new stand alone or are you going to jump ship to the 6mt? You could probably do t400 as well if you want that sick constant boost between gears though.
Looks like your peak tq increased just a little but the top end HP went way up due to the free flow of those turbos.
You're a picky guy on tunes so when you say it's smooth it must be VERY smooth.
Looks like your peak tq increased just a little but the top end HP went way up due to the free flow of those turbos.
You're a picky guy on tunes so when you say it's smooth it must be VERY smooth.

Last edited by rcdash; Aug 22, 2012 at 06:34 AM.
Was there no way the GTX turbos would fit up high with the JWT manifolds? I've been contemplating these hoping they could fit without having to relocate them and redo all the piping.
Last edited by djamps; Aug 22, 2012 at 07:33 AM.
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Thread Starter
New Member
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Joined: Jul 2005
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From: Chapel Hill, NC
Hal spoke to JWT about this and they were considering designing an adapter of some sort, but I don't know if/when that will ever materialize. The main issue is the engine mount right in front of the compressor housing inlet. The JWT manifold positions the turbo very close to the block.
Looks like my custom kit might be in the same situation with that engine mount? I can vaguely recall being told I would need some kind of spacer for GT28's.


Last edited by djamps; Aug 22, 2012 at 12:46 PM.
I would still prefer what Dynosty did with the kit. Now that they have the Tial stainless housings available for the GTX urbos, it makes servicing very easy. The only thing I would do is move the wastegates downstream, perhaps at the elbow (just before the turbine inlet) so that they are easy to get at/service. Other than that it really is the perfect TT setup.



