VQ35DE Intake Development:

We’re proud to be the producers of the highest horsepower stock block, stock head VQ35 in the world. Our goal was to optimize all of the external components of the engine, so that further internal engine work could reap the maximum possible gains.

During dyno testing we found that a significant amount of vacuum was being pulled in the intake plenum and it became our main focus to for one find out how much power was being robbed, and find a solution to get that power back.

The test we did involved physically removing the upper plenum in the middle of a dyno run, to see exactly what kind of power the engine would produce with the intake runners entirely open to the atmosphere. We found 25+ wheel horsepower. Following that incredible discovery, we built an extremely large plenum out of aluminum to see if plenum volume was the issue. No gains were found, so the next logical step was to increase airflow into the plenum. A large 3.5” hole was put in the top of the plenum with a velocity stack that would allow airflow additional to what was coming through the factory throttle body. That 25 wheel horsepower came right back, so inlet flow was more of an issue than the actual plenum flow. The engines power output at this point was 334whp.

The next step was to make a large 90mm throttle body work with our Motec M800 and to develop a plenum that could freely get the air to the runners without being a restriction, both in the elbow and throughout the plenum closer to the runners themselves. We enlisted Carbotron for this job and he built us a fantastic carbon test plenum.

With a complete intake system in a fully drivable state we found 18whp and are now making 327whp. We’re now working on a solution for the daily driven crowd, that will allow the power to be found without sacrificing drivability or engine smoothness. Perhaps only a sports version will be available that somewhat decreases drivability, we will know more in the future.

350z Compression Rod Spherical Bushing:

Not available anywhere else on the market, SG wanted to approach the task of converting all of the pickup points on the 350z to solid spherical bearings for maximum steering response and tire compliance. One of our vendors, SPL Parts, already had the 350z lower control arm bushings done as sphericals, so all that was left was the large compression rod bushing. This rod controls the caster and helps control the wheel under braking, steering and any lateral load as deflection in this bushing will alter caster, toe and camber.

We designed the part with a 10mm spacer to be able to run either at the OE rod height or with it raised into the chassis 10mm, to be used with a re-located lower control arm to alter suspension geometry to aid in camber gain in bump and to possibly alter anti-dive properties.

The compression rod prototype has been completed and tested on our 350z race car with fantastic success along with the SPL solid front suspension components. With our wing and splitter the car is currently producing upwards of 1.7g’s through corner 2 and 4 at Mosport, but more importantly the previously delayed and slightly numb steering feel is all but a distant memory, and has been replaced with instantaneous lightning fast direction changes the instant you touch the wheel. Any input is felt through the seat as a change in direction almost before you even realize you’re steering. The car doesn’t go anywhere on its own unless you tell it to go there with the steering and even minor corrections are felt instantly – the way a racecar SHOULD be.

Boost Leak Tester:

Effects of boost leaks and vacuum leaks on engine performance:

• Delayed turbo spool
• Works the turbo harder to create the same boost pressure
• Dangerously rich and lean conditions when in and out of boost respectively
• Loss of driveability
• Vacuum leaks can totally inhibit the engine from running correctly
• Loss in power and reliability

The SG-Motorsport Solution

• Accurate and lightweight boost leak tester with both function and form
• Designed by professional tuners, with the novice in mind.
• Anodized body and 0-35psi liquid filled pressure gauge with SG-Motorsport logo on the face
• Schrader valve to pressurize the system
• Ability to see small leaks by watching the gauge which otherwise may not be noticeable by ear
• Will accept 2, 2.5 and 3 inch couplers
• Also a fantastic option for Naturally Aspirated cars to detect vacuum and manifold leaks
  
  Our boost leak tester is now available! Click Here To Purchase Online

SGM Grand Sport Headers:

The SGM Grand Sport headers are being developed based on the need for a properly tuned header to extract the potential out of the VQ35. Many headers already exist on the market, but they all share one common flaw – they are too short. The factory exhaust manifold is very short in order to get the cat as close to the heads as possible –for maximum efficiency and for cold start emissions. This was Nissans primary concern. The cat section then extends down to the bell housing area of the transmission, where there is a 2 bolt flange to the factory Y-Pipe.

Instead of having our headers go to the cat, we are replacing both the factory exhaust manifold and the cat pipe, and meeting the factory Y-Pipe with a 2bolt 2.5” flange. By doing this we can use proper length primaries (690-700mm) as well as a properly designed merge collector that will keep efficiency in the system up – which in turn will keep power up. We have contracted SPD to do our collectors for us, and they have been fantastic so far. Their collectors are on par with the best in the business, featuring fully TIG welded joints, back purged and ground smooth internally.

We have used a local tube bending firm to bend up 0.065” 304 stainless for us, and will as a result have perfect bends for every joint – large radiuses are used wherever possible to minimize flow restriction. Unfortunately due to the complex nature of the headers, the primaries cannot be bent all in one tube, as a mandrel bender needs at least 3 inches of straight between each bend. To form the primaries to the shape of a pipe we had a die machined out of tool steel that stretches the tube to the width of the port, then is clamped to have the same height as the port. It is then slipped inside the flange and welded on the inside for a seal, and on the outside for support.

Finally, we have contracted a local water jetting company to cut the flanges at the head for us, using 6 individual flanges – each pipe will be individual. This makes removal and installation of the headers extremely straight forward, allowing installation in less than an hour from the time the factory manifold and cats are removed.

Our prototype heaeders use a 3 step primary, that start at 1 3/4, move to 1 7/8 and enter the collector at 2". The collector shrinks to a 2.25" nozzle that then transitions up to 2.5". Our race prototype version went to a 2 into 1 slip collector to go to a single exhaust, but our production version features 2.5" 304 stainless flanges that will mate with the factory Y-pipe, or any aftermarket exhaust system that bolts to the factory cats.

On our initial dyno testing of our Coast Fab headers vs. Factory manifold and cats, we found gains of over 30whp, and torque across the board. Everywhere. When we tested our Coast Fab headers to our new lager headers on our race car, we saw an additional 13whp gain above 6000rpm, proving that the larger diameter piping and collectors did infact make more power up there. To balance the top end and bottom end power we have elected to stay 1 7/8 for the primary piping only using one step, and staying with a 1 7/8 collector.

Our SGM Grand Sport headers will be available for order shortly, we have already sold multiple pre-production sets.

Initial price target has not yet been established but is going to be in the range of 1800-2200$ USD. We are working our hardest at trying to get our manufacturing costs down so that we can offer the product to you at a lower cost, please contact sales@sg-motorsport.com with inquiries.

Click HERE to view our longtube header photo gallery.