***NOTE: This is not a sale thread, but rather a tech thread for our new single turbo kit. This thread is meant to inform about a new product.***

SOHO Motorsports Single Turbo Kit
2003-2007 Nissan 350Z and Infiniti G35, VQ35DE Engine


SOHO Motorsports Single Turbo Kit: The Design
With Momentum Performance having to close its doors earlier this year, the industry was left with a vacancy for a single turbo kit for the 350Z/ G35 community. After competing in numerous track days from regional NASA events all the way up to Global Time Attack events with the Momentum Performance turbo kit on our SOHO Motorsports G35. Over more than a 16 month period of unebelievably hard abuse on the car, we were able to discover a few items that needed to be changed in order to help increase the efficiency and performance of this kit. With all of the knowledge we posess of motorsports, the owner of SOHO and head tuner is Nik Sohoritis. With his former NASCAR engineer expertice and knowledge of mechanical engineering, Nik has calculated everything for this turbo kit to ensure that it will be one of the most efficient turbo kits in the market. From the flow of the air via new routing of pipes to the efficiency of the intercooler. Throughout this article we will be discussing the basics of the turbo kit from the choice of turbo, intercooler and cold side piping and the reasons we are doing what we are doing with calculations that describe to you why we have chosen these items.



The Turbo:
Before we begin I must note that our kit is in no way based off of or uses anything similar to the Momentum turbo kit, but for sake of reasoning we will be using that to compare to ours in this article because of its popularity as one of the best single turbo kits for the Z and G platform. The Momentum Performance turbo kit utilized the Garret GT3582R turbo with a 1.03 A/R custom Tial turbine housing. This created a very linear power curve from 3500 to 6800 rpm on any VQ35 motor with a compressor efficiency ranging from 74 to 75 percent at a boost level of 9 psi throughout the power curve. When comparing the GT3582R and the all new GTX3582R, which we will be using for SOHO kit, the inducer is 0.05 inches larger in diameter and the exducer is .02 inches larger in diameter for the GTX3582R. This results in a slight increase in airflow and a larger trim. In the single turbo kit that we are designing and building, we have chosen the all new Garret GTX3582R turbo with a Tial 1.06 A/R turbine housing that will have an increase in compressor efficiency throughout the power band by at least one to two percent. With this increase in efficiency the compressor is pumping air to a point where the air is not getting heated more than it should be, based on the pressure ratio, thus resulting in cooler and denser air into the intake system and in turn yielding more power. The Tial turbine housing that we have chosen incorporates a slightly higher A/R ratio that will bring a smoother transition into boost and will allow for more exhaust gases to flow in the higher rpm range with less restriction.



The Intercooler:
In the design process of an intercooler there are two essential characteristics to consider in creating an efficient inercooler as possible; internal flow area and frontal core area. The internal flow area of an intercooler core can be determined by multiplying the core length, core height, and the number of cooling air channels in the core. Both of the intercoolers, for our turbo kit and the Momentum Performance turbo kit are using the plate and shell style intercooler core. A rule of thumb to always follow is that when the internal flow area of an intercooler core is large, the pressure loss through the core will be small. The difference with the intercooler that we have chosen for the SOHO Motorsports single turbo kit is that we have increased the overall height and thickness of the core and decreased the length. After a few calculations we were able to determine the intercooler core that we were going to use for our turbo kit when compared to the Momentum intercooler had almost an eighteen percent drop in overall pressure loss. Once we had determined the core size for the intercooler we shifted our attention over to the end tank design, where we found that the two inch end tanks on the Momentum intercooler were not going to be sufficient enough in creating a system that minimized pressure loss. We increased our end tanks by almost a full inch on both sides and decreased the angles for the inlets to allow for the air to travel in a more uniform and less turbulent manner.



The Piping:
Many hours were spent in determining the best way to route the cold side piping for our turbo kit, and once we determined the routing we were able to see a huge benefit compared to the current setups on the market today. The current single turbo kit takes the charge air coming out of the turbo and goes thru the intercooler, up along the topside of the radiator and then into the intake manifold. There is a problem that occurs when routing the cold side piping this way, in that you are heating all of the air going into your throttle body after you have cooled in the intercooler, since the intake pipe is sitting on top of the radiator in stagnant heat within the confines of the engine bay. We have completely avoided this path and have decided to take the charge air coming from the turbo and route the piping in between the radiator and sway bar on the bottom side of the vehicle, to where it would come into the intercooler from the passenger side and out the driver’s side and straight into the intake manifold. With the charge pipe being run close to the bottom of the vehicle, the air that travels underneath the vehicle and under this pipe will help in slightly reducing heat soak of the air before it travels into the intercooler, thus creating a somewhat pre-intercooler cooling system. Along with the re routing of the traditional single kit to the bottom we also have increased the overall diameter for the cold side which has been calculated to withstand airflow for up to 800 horsepower (1200 cfm) before there would be any pressure loss in the pipe from the air traveling at speeds higher than Mach 0.4 (400 ft/s).

Stay tuned as we discuss the routing of the exhaust side of the piping and determine which type of waste gate and blowoff valve we are going to use (diaphragm based or pneumatic piston based). Plus we will be updating with all dyno and track results.

 

Very nice guys! I look Forward to seeing your product hit the market hopefully its not to pricey but id understand if it is why it is. But definitly to you guys for taking the challenge of producing another turbo kit for our car! will you guys be making "suppliment kits" i guess you would call it to adapt to true dual exhaust systems or will it come out to the factory cat location that way we can use any after market exhaust or even the stock system. Also with your kit will you be including headers into your design?Also any plans for a TT design with Twin intercoolers?

 

Thanks! We have been working really hard and taking the extra time to ensure that this kit will truley be one of the most efficient kits on the market. The kits will be made so that any aftermarket catback exhaust will be able to bolt up directly to our kits. I would not recommend installing the stock exhaust system to our kits as it will create a ton of back pressure in the exhaust side of the turbo and thus hurt horsepower gains. We are in the process of designing headers for our kits at this time as well and should be able to inform you guys within the next couple of weeks as to what we have come up with. We do have plans to expand into the HR field with a single turbo kit but do not have any twin turbo plans, but we have not ruled the twin turbo idea out yet! Stay tuned as we keep updating this thread with more info and pictures!

 

Looks good but i would ask a mod to move this to the FI section as it might get a lot more attention there.

 

Sub'd..!!

 

Definitely would be interested in this kit as I had plans on getting the Momentum before they went under and was hoping by the time I get the funds for it would still be able to find one which is doubtful. Hopefully you guys make your kit to connect to the header like there's as I just bought a set of there headers and hoped to be able to use them with which ever kit or custom build I where to do.

 

nice, I know you guys were originally using the sts, and then momentum for your sponsored track car, I'm hoping you'll be taking the best of both plus a little of your own secret guru juice to make a decent kit for market? sub'd for results, turbonetics is a joke and there really isn't a decent source for single turbo kits except for boosted performance... I love it when people go out on a limp and make something cool!

EDIT: Saw the GTX turbos at SEMA last year, definitely the way to go. REALLY wish they'd been invented back when I bought my GTM kit...

 

approximate for pricing yet?

compatible with 5AT or just 6MT?

 

^Can't discuss pricing here since he's not a forum sponsor. Best bet is to send him a PM.

 

ahh, yes...well, in that case

 

It will be difficult to find another momentum kit to purchase as they have become scarce, they were a great company and created great products. We are stepping in with our turbo kit to fill in the empty space that the industry has right now for a well designed turbo kit. We are going to make our kit to fit the stock headers and the momentum headers as well as try to make the majority of the other headers that are out in the market today work as well.

 

Right now the kit that we have designed will be for the six speed manual transmission...

 

Yea we have learned a lot between the STS kit and the momentum kit, so know we have taken the flaws of both kits and have calculated everything to ensure that we have one of the best kits out in the market. The new GTX turbo is absolutely phenomenal as to what it can do in the midrange for our vehicles as it is highly efficient on the compressor map, this kit will have some great horsepower results!

 

That is a great thing to hear!! There arent to many single turbo kits out there worth getting that comes complete with quality components all round. I do know of one site that still lists there kit for sale but I highly doubt by the time I have the money for it they will still be selling it. If your guys kit is going to fill that gap and be better than I will definitely be buying one. I was starting to think that I was **** out of luck for a well designed single turbo kit but came across you guys. Keep up the good work!!

 

Got this question on another forum and thought it was worth sharing the question and our response:

The turbo that we are running is a 35 just like the majority of the other single turbo kits (the newer Garret GTX35) because it is a great turbo with a healthy ballance between nearly no lag and great high end power on anything from stock to built engines, but that turbo is also largely used due to the amount of room that is available to place the turbo up front is very limited. A larger turbo can be used but some more modifications would have to be made and we are trying to make this kit as straight forward as we can without much modification on the customer's end. There is not only one way to route the turbo pippin up front, there are a few ways and the way that we have routed it is the most efficient. Running the pipe under the engine bay you will be reducing air temp and not be heat soaking the pipe after the air has traveled thru the intercooler. The majority of the other single turbo kits that have run their piping the other way have added their own "two cents" onto the previous design and have not determined a way to avoid heat soaking the intake pipe. When you think about it the design change is quite simple on this pipe but very effective. This is just one of the few things that truly makes it different than the others, among the other piping size changes and the turbo housing.

The diameter of the pipe that will be coming off of the turbo on the cold side will not be like the previous kits where a 2.5" to 3" coupler is used and then the remainder of the piping is 3". The design of the piping for our kit that we have used is going to be a 2.5" pipe until the inlet of the intercooler which is 3". No before you say to yourself "bigger is better"... What this does is allow the air to keep the same velocity since it is now not having to overcome a difference in pressure gradients with the larger opening that the previous kits have. The way we have run this pipe will also help in reducing the turbo lag not by a huge factor but will definately help because it will sustain the same velocity up until it reaches the intercooler and then create a vacuum effect thru the intercooler. Air will always want to travel the path of least resistance or the path that has the lowest pressure. For example, the same concept holds true in an engine, when a valve opens there is low pressure inside of the cylinder so when atmospheric air, which is pressurized sees this low pressure it will automatically rush into the cylinder and fill the cylinder up as fast as it can to get out of the high pressure zone. Alot of the engine builders in motorsports today use this concept and apply it when it comes time to determine how to increase the volumetric effiency of a cylinder above 100 percent.

I can see where your skepticism may lie in us claiming to have made changes to the design to fix some issues, but this kit will be a much better design than previously comparable kits at a price that is nearly the same if not cheaper. We arent re creating the turbo kit, just fixing the best type for these cars: the single turbo kit. Not remote mount, not twins, not supercharged.... SOHO Motorsports Single Turbo Kit. :thumbup: