SOHO Motorsports Single Turbo Kit & Motordyne

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We have been asked recently about the effects of the Motordyne Engineering 5/16” intake manifold plenum spacer along with our single turbo kit and a few months ago we conducted a test on our 2005 non-revup Nissan 350Z. Previous tests that had been done with the SOHO single turbo kit were with the stock exhaust manifolds and no intake manifold plenum spacer, thus providing 392 hp and 406 ft-lbs of torque at a boost level of 8.58 psi. Nissan Engineers have done a phenomenal job designing the VQ35DE engine but as most of us know the stock plenum was not designed to its full potential. The plenum that comes on this vehicle from the factory was not designed particularly to aid in airflow in a forced induction system let alone any performance additions, meaning that that space inside the plenum is restrictive and detrimental to making horsepower. 

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Motordyne Engineering has done an excellent job of research and development on theri own in regards to the airflow restriction and benefits that can be achieved inside the VQ’s plenum. With the addition of the 5/16 inch plenum spacer adding volume, the initial pressure drop that is inside the plenum is reduced by a factor of 9, thus increasing the overall airflow inside the plenum. With increased airflow comes an increase in the horsepower capabality. In previous tuning sessions with customer cars on NA setups along with plenum spacers we have seen good increases in horsepower numbers as high as 10-15+ rwhp. When we decided to add the spacer to our 350Z with stock manifolds and our turbo kit we were expecting good results and the goal was to see how low of boost we could run to make the same near 400 numbers that are common on daily driven setups in an effort to strain the motor even less than the very minimal amount it already does. As you can see in Figure 1 below, the two graph lines represent the SOHO turbo kit with no plenum spacer at boost levels of 5.82 (red) psi and 8.58 psi (blue).

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Figure 1.

As you can see in Figure 1, in order for a 10% increase in horsepower and torque there is a 32% increase in boost pressure that is required, thus more stress on the engine internals. After installing the Motordyne Engineering 5/16″ plenum spacer and some quick tuning of the stock computer with the aid of UpRev Osiris, we saw a drastic increase in power and a drop in necessary boost pressure to achieve almost the same power levels at nearly half the boost. In Figure 2 below, these were the horsepower and torque values that we achieved with only the addition of the 5/16” plenum spacer, and in Figure 3 you can see the comparison of horsepower numbers against the dynamometer pull at a boost pressure of 8.58psi.

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Figure 2.

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Figure 3.

There was around a 9 rwhp and 14 ft-lbs difference between the two dynamometer pulls at SAE but there was a 45% difference in boost pressure to achieve these values. The plenum spacer definitely allowed the engine to breathe much easier and thus aided in creating incredible power at such a low boost pressure. This is a great discovery that we found on the dynamometer because it takes a substantial amount of stress off of the engine internals and allows the engine to operate at a more efficient level. With the addition of the plenum spacer we were able to achieve an incredible 26.21 horsepower per pound of boost and 32.26 ft-lbs of torque per pound of boost, making this turbo kit even more so one of the most efficient kits in the market in terms of power and torque per pound of boost.

As a comparison for sake of argument, a few months ago we had a 2003 Nissan non-revup 350Z with stock exhaust manifolds that we installed a Motordyne Engineering 5/16” plenum spacer along with a comparable single turbo kit. In Figure 4 below you can see the comparison between the SOHO Single Turbo Kit (blue) vs the Momentum Single Turbo kit (red) on identical vehicle setups on the same Dynojet dynamometer and at SAE.

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Figure 4.

The comparable single turbo kit, which can be seen in Run 11 (red), made great safe power for a stock daily driven block but required around 42% more boost pressure to make the same power as the SOHO Turbo Kit (blue). Many people may say that the turbo that we have chosen is the main reason as to why we make these values, which is a large factor, but the overall design of the turbo kit along with the Garrett GTX35R turbo that we have chosen is why we make such great power at such low boost.  Be sure to visit our online store and our turbo kit section for more information and contact us to place an order for your single turbo kit!

SOHO Motorsports Nissan 370Z Single Exit Catback Exhaust

There are very few companies in the industry today that build a single exit catback exhaust for the Nissan 370Z platform and with the success of our 350Z/ G35 single exit catback exhaust system we decided to build a single exit catback for the Nisan 370Z.  The SOHO Motorsports single exit catback exhaust system is constructed from 3″ diameter T304 18 gauge stainless steel piping providing a 55 percent decrease in weight over the stock exhaust.  As you can see in the pictures below we have taken extra steps to ensure that the fitment and clearance of the exhaust was not going to create any issues for the end user.   370Zdisplay   20140729_143214_wm   20140729_143229_wm   20140729_143243_wm   Once the final design of the SOHO Motorsports single exit exhaust was completed, UpRev Osiris was used to adjust the air/ fuel ratio parameters and determine the horsepower/ torque gains.  After a few Dynojet dynamometer pulls and adjustments, we acheived an 8.03 hp/ 10.73 ft-lb of torque increase over the stock exhaust system as you can see below! 370Z Dyno Graph *The vehicle that was used for the prototype still had the stock OEM intakes, catalytic converters and y-pipe, the only thing that was changed was the muffler section of the exhaust after the y-pipe.*

Here is a sound clip of the exhaust on the vehicle:

SOHO Motorsports Single Exit Catback Exhaust System Video Clip 

We are no offering this exhaust system to the public at $699.99 plus shipping to your location, contact us today to place an order for your SOHO Motorsports single exit catback system for your Nissan 370Z!

AP-Racing Radi-CAL By Stillen BBK Now Available!

For many years, AP Racing has provided brake systems for a majority of world class motorsports applications, and with their success on the track they have decided to bring that technology towards the street cars.  AP Racing and Stillen have come together to build one of the newest and most effective big brake kits in the industry to date.  Their engineers have built a big brake kit that offers a 20 percent lighter and stronger caliper than any other big brake kit available with a pressure forged aluminum process and internal seals rated for supercars like the Bugatti veryon.

Why Radi_CAL1

The engineering behind the rotor structure and use of the “J-Hook” has allowed for reduction in un-sprung mass and also aid in thermal efficiency.  The “J-Hook” design allows the rotor to vent and also help in initial bite between the brake pad and the rotor as the leading edge of the J-hook will allow the driver to get a better feedback once the brakes are applied.  The two piece floating rotor design allows the rotor to expand and contract under thermal stress and allow the rotor to remain centered, thus reducing brake pad knock back.


For the weekend racers, AP engineers have thought about the time between sessions that people have while at the track and the additional time it takes to replace brake pads on other big brake kits.  AP Racing has incorporated a removable “H-support” on top of the caliper to make changing brake pads a breeze as seen below.


These brake kits are now available for the following manufacturers: Audi, BMW, Cadillac, Chevrolet, Chrysler, Dodge, Ford, Infiniti, Jeep, and Nissan.  Contact us today for pricing on this big brake kit for your vehicle and we promise you that you will not be dissappointed!



SOHO Motorsports Single Turbo Kit Comparison Results

Over the last few months we have received a lot of interest from customers in that they were curious to see what the differences were between the Garret GTX3582R turbo, which is currently supplied in our turbo kit, and the Garret GT3582R turbo.  At SOHO Motorsports we are always researching different products and combinations of products to inform our customers, and this past weekend we were able to perform a test between the two different turbochargers on our turbo kit.  In this test we tried to keep all of the variables the same to provide an accurate comparison and the only adjustment that we had to make was the air fuel ratios so that they were the same for both of the runs with each turbo setup.  In the graph below you can see that the red line shows the run with the GT3582R turbo and the blue line shows the run with the GTX3582R turbo.

Garret GT3582R vs Garret GTX3582R

Garret GT3582R vs Garret GTX3582R

In the graph above, between 3000 to 3500 rpm, there is a 13.62 percent difference in horsepower and torque that was calculated.  Due to the greater efficiency of the GTX3582R turbo, the increase in power can be seen as soon as boost starts to come in and eventually starts to taper off throughout the power band.  The overall increase in power throughout the power band was 2.48 percent until the maximum rpm was reached between the two turbo combinations.  With the current layout of the piping of our turbo kit, both turbo combinations were able to reach maximum boost (5 psi) at the same time, which was around 3350 rpms.  A comparison between the two turbo combinations and a non turbo stock VQ35DE nonrev-up can be seen in the graph below, where the green line represent a stock VQ35DE.

Garret GT3582R vs GTX3582R vs Stock VQ35DE

Garret GT3582R vs GTX3582R vs Stock VQ35DE

The graph above will allow you to understand the gains that can be seen when a VQ35DE and forced induction combine.  When comparing the turbo combination with the GT3582R and a naturally aspirated VQ35DE, there is a 32.31% increase in horsepower and a 39.38% increase in torque that occurs.  The GTX3582R turbo combination creates a 34.06% increase in horsepower and a 40.90% increase in torque at a boost pressure of only 5 psi!  As boost pressures increase, the difference in power between the two turbo setups will be exponential as the GTX will be in a higher efficiency range in the compressor map, which will allow for more power to be made at the same boost level.  In conclusion, customers that are planning to build their motor and run more than 6 to 8 psi of boost, we would recommend selecting the GTX3582R turbo, while the customers that are planning on using the turbo kit on a stock VQ35DE at a low boost pressure to select the GT3582R turbo.  The benefit for the customer who will be using the stock motor and the GT3582R turbo is that they will be able to save $500 off of the total price of either SOHO Motorsports turbo kit package!  Please visit our online store for the updated pricing on the single turbo kit with the GT3582R turbo and visit the SOHO Motorsports turbo section for more information about our single turbo kit or contact us today if you have any questions.

#44 SOHO G35 Finishes the 2013 Season Strong!


The end of every racing season is usually the busiest and this year busy didn’t even begin to describe how we finished the year. After a long racing season of ups and downs, battling new car blues, on the newly rebuilt #44 SOHO Motorsports Infiniti G35 we were eager to finish out the 2013 season strong with quite possibly the two most important races the #44 car has seen yet. Our November schedule had us going from our shop in Charlotte, NC nearly 5,000+ miles round-trip to the 10th Annual Super Lap Battle / Global Time Attack Finale at Buttonwillow Raceway in California. And then less than 10 days later we had to go from CA to NC and then down to Florida for the North American Road Racing Association USTT Season Finale at Sebring International Raceway only to leave there and go to Indianapolis for the Performance Racing Industry show a week after that. November was a crazy month for us and we are just now getting caught up on the website articles and updates including some quick summaries of the final races of 2013. For more in-depth details of each race please visit our driver’s site at


The 10th Annual Super Lap Battle / Global Time Attack Finale at Buttonwillow Raceway is easily the biggest Time Attack event on this side of the globe. All of the fastest TA cars and teams on this hemisphere make the annual mid November trek to sunny California to push their vehicles to the limit around the dustbowl that is Buttonwillow Raceway. With the event being at the same track for the last ten years it has become a staple in the North American TA scene and is where the fastest cars in the country duke it out to crown a champion each year in multiple classes. Having only had the #44 G35 built for a few years now this was our first time at the event so we were expecting to do okay but with the heavy hitters out there and no experience at the track we had reasonable expectations, but were hoping for the best. With a nearly non stop 36 hour tow from NC to CA out of the way our driver Kevin Parlett arrived at Buttonwillow and put on his helmet and prepared for battle around the 3.1 mile track with 12 turns covered with tons of dirt and dust.


Our first Super Lap Battle didn’t quite turn out the way we wanted it to but the adventure as a whole was worth the raceday headache. In the first session while learning the track and chasing the setup we had some contact with another car and had some slight body damage to the right rear fender and aero package. After taking a hammer to the damage and getting it back into working shape Kevin took a deep breathe and went back out in the second session to work off the nerves and learn the track some more in preparation for the 3rd session which most were expecting to be the fastest. Unfortunately SLB is only a one day event which for us was a pain because it is a track that is nearly impossible to learn how to drive or setup a car properly in just one day. Plus with us being from the East coast it was much more technical and tighter than anything we were used to along with the added joy of dirt and dust on nearly the entire track surface, so needless to say we were behind the 8 ball if not completely off the pool table before we even started hot lapping. Either way we made a few adjustments after the 2nd session and went out in the 3rd and 4th session gaining a ton of time in each outing but the one day wasn’t enough to get it done. Frustrated, tired and worn out we finished the raceday in 7th place in Limited RWD. No where near the podium we had hoped for and just barely missing out on the 2013 Global Time Attack Limited Class championship by a few measly points. The result wasn’t what we wanted but we knew our first time to the big game was going to involve a steep learning curve and hopefully with what we learned this time out we will be much faster next year for the 2014 SLB. Either way we didn’t have much time to dwell on the poor finish as the next morning we had to leave California and trek across the country for our last race of the season just 9 days later in Sebring, FL.

NARRA Sebring Nov.22-24, 2013 ColourTechSouth DL - 5 047

With an uneventful but unbelievably long drive back to the shop in NC we quickly unloaded the car and got it all cleaned up from the tons of dirt and dust from Buttonwillow and our cross-country trip on an open trailer. Then we addressed some of the damage, changed the tune to comply with the NARRA power to weight rules and changed the setup to comply with the completely different and very bumpy Sebring International Raceway. Going from Buttonwillow, CA to Sebring, FL in one week wasn’t just insane for having to tow that many miles but the tracks couldn’t be more opposite from each other. Buttonwillow was 3 miles of tight technical dust covered asphalt that barely allowed us in 5th gear and Sebring was a ginormous 3.75 track with multiple straightaways that allowed us to top out 5th gear not once per lap but multiple times each lap and may have been the fastest track we have ever been to. Needless to say our driver was excited to stretch the legs of the #44 G35 one last time to finish out the season and we knew that with such a large track it would play into the hand of the #44 car and hopefully put us on the podium.

NARRA Sebring Nov.22-24, 2013 ColourTechSouth DL - 10 007

The NARRA USTT finale was the final points race of the season and we were mathematically in the running for the 2013 NARRA USTT North Cup Championship in TT1. All we needed to do was finish in the top 3 and beat two fellow racers who were ahead of us in points. It was a tall order but certainly possible and after our dismal finish in California we were all ready to finish the season on a high note and hopefully walk away with a championship as well. After driving across the country we experienced every weather from 30mph winds to snow to sweltering heat and everything else, so when we got to Florida and felt the sunny 85 degree weather we were very excited to be wearing shorts a few weeks from Christmas and anxious to race in such perfect late season weather. Bright and early Saturday morning we got the car unloaded, passed tech, attended the drivers meeting did some reconnoissance laps and before we knew it we were in the final first session of the year and excited to see what the #44 car could do around the infamous Sebring.

Once again we were at a track we had never been to before, so the first session was used to learn the line and sort out the car setup all while still going as fast as possible knowing it was a one day double points event with only 5 sessions so each session was crucial. Luckily for us after the first session we were sitting 2nd in TT1 and one of the racers we needed to beat for points did not show up, so our chances were looking pretty good early in the day. Going into the second session we made some tire pressure and sway bar adjustments and went out and put down what would end up being our fastest lap of the day for us. Unfortunately on that same fast lap on one of the straights our 5th gear went out on us and refused to let us engage without some serious abuse. This transmission issue would plague us for the rest of the day along with the very high FL temperatures making the track less cooperative as the sun baked the track bringing out all of the grease and overheating our Hankook Ventus TD’s. With the NARRA USTT rules every class is allowed to run racing slicks but with our car having just come from SLB/GTA we were still on our 80 tread wear Ventus TD’s designated by their rules so we were at a slight disadvantage but we were still holding our own firmly on the podium. Unfortunately in the last session of the day we were bumped from 2nd to 3rd but we were still on the podium and with that podium finish we had clinched the 2013 NARRA USTT North Cup Championship for TT1! It was a hell of a way to finish the 2013 season and we couldn’t have been happier to have won our first TT championship in the #44 SOHO Motorsports Infiniti G35 and gave us a ton of momentum going into the upcoming 2014 season. Until then enjoy the photos and videos in this post and be sure to check back for more updates in the future along with more in-depth info about these races at


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