Archives for : November2011

Titan Drop-In Air Filter

This 2010 Titan was dynoed to see how just dropping in a simple K&N air filter performs.

Blue run was on the OE air filter and red performed with the K&N air filter.  Good gains for only an air filter.  Mixture leaned out as a result of the increased air flow.

NISMO 370Z RC Track Car

Nissan is offering the 370Z track ready for the serious racer\enthusiast.

From Nissan:

If you’ve ever wanted to extend your love of the iconic Nissan Z-car from the street to the track, now is a good time to take action. Nissan Motorsports is now offering Nissan 370Z race cars for customer orders. The track-ready Nissan 370Z NISMO RC is based on the street legal Z-car, but is significantly lighter and fitted with a FIA-compliant roll cage, fire extinguisher, racing seat and numerous NISMO performance upgrades.

The Nissan 370Z NISMO RC has been designed to conform to International FIA GT4 and World Challenge GTS class specifications. With some modifications, the Nissan 370Z NISMO RC can also compete in the Grand Am Continental Tire Challenge GS class.

Weighing in at 2,954 lbs., the Nissan 370Z NISMO RC features NISMO race exhaust, NISMO tuned ECM, high capacity NISMO clutch, flywheel, engine oil, transmission and differential coolers and a Recaro racing seat with 6-point racing harness. A Sparco racing steering wheel and a revamped and race-ready carbon fiber switch panel are also part of the RC package. The 3.7 liter Nissan VQ37VHR powerplant is rated at 355 horsepower and 276 ft. lbs. of torque. Numerous hose and connector upgrades have been added to meet the rigorous demands of track use.

Nissan Motorsports provides an easy way to race its 370Z in a competitive professional racing series. Interested parties may contact Nissan Motorsports at 1 (888) 833-3225 for more information.

Twin oil coolers sitting below and race muffler.

Octane Vs. Boost

I figured it would be a good idea to offer a post on boost vs. octane to help Z owners make educated decisions for themselves, regarding how much boost they can safely run.
Not all Z engines are going to have the exact same threshold for knock for a given PSI, but I can offer what the norm is based on tuning hundreds of Z cars, and tuning with a Knock detection system for some time now.
The following is the safe norm for most standard set ups that are properly tuned in the mid to low 11 to 1 air fuel ratio range with standard 8.5 to 1 compression.
91 octane 14 PSI
93 octane 16 PSI
94 octane 17 PSI
100 octane 20 PSI
These would be the average safe boost numbers for the given fuel octane with conservative ignition timing in the maps, running more aggressive ignition timing would require running even lower boost for the given octane.
Of course there will always be anomalies…….
I have seen where 10 PSI wants to detonate on 91 octane, I know a car that can only safely make 13 PSI on 94 octane, that is with only 13 degree’s ignition timing in the top of the high load areas of the map. That car put down great numbers that appeared as though is was running normal boost and timing, this was because this car had abnormally high compression.
Some cases you can make higher PSI for the octane than the numbers I am offering, but they are not common, typically it is because the engine has lower compression.
It is possible to safely have a small higher spike as long as most of the boost is in the suggested range.
Many built engines need to run even lower boost levels than the ones suggested because they have higher compression. As the engines get older, some blocks have been decked more than once and some heads have been milled more than once, some piston companies are also making the pistons to slightly higher compression.
When tuning, several things are juggled to stay in the safe range that offers no detonation.
Compression, Boost, Ignition Timing, Cam Timing, backpressure, and heat are the main variables.
If the engine has higher compression, you will need to run less boost to keep from having detonation.
If the engine has less compression, you can run more boost. The final power numbers that are safe for a given turbo size and group of parts are commonly similar no matter how you get there as far as higher compression with lower boost or higher boost with lower compression. Basically you can only have so much pressure in the cylinder for a given octane fuel, before the fuel will ignite from heat.
Less heat from removing exhaust restriction can allow you to go a little higher, and more efficient intercoolers can allow you to go a little higher as well.
Bolting on bigger turbos move more air and allow more flow on both the intake and exhaust side, this allows more power at the same boost level.   Bolting on a larger turbo does not allow you to make more boost with the same octane as a smaller turbo, at the same pressure you still have similar heat that wants to ignite the fuel at the same pressure for a given octane.
If a engine has experienced a lot of detonation, it will be more detonation sensitive, this is because detonation causes pitting of the heads and the top of the pistons. These small pits have sharp edges that glow red with heat much easier than a smooth surface. These “hot spots” will start detonation very easy and require running even lower boost to prevent detonation.

I use to believe it was safe to run about 1 PSI more than I listed, this was before I invested in a knock detection system.
After tuning with a knock detection system only a couple times, I can not believe I ever tuned without one.
With the proper tools, it is very easy to hear knock and know the real knock threshold for that cars set up. It is amazing how much knock can be present without being able to hear anything with the human ear, inside or outside the car in a dyno room.
I am offering the octane vs. boost guide based on what I have found to be average safe levels with tools that allow me to know if the engine knocks and not just a guess or thinking everything looks fine.
No matter what a tuner tells you, I would not recommend running higher boost than I have listed unless the tuner uses a knock device to know your true knock threshold.
You can also install a knock detection system and the system can be set up to pull timing if knock is detected like a lot of newer car systems.

Enjoy the boost, but keep it safe!

GTM Stage 2 SC

We had the opportunity to get our hands on the new GTM Stage 2 SC Kit.  The great thing about the kit is that its very quiet not like your typical Vortech units and the way Sam@GTM has designed the kit you can’t even see the blower with the hood open.  Making it a much slicker and sleeper look.  The heart of the kit is the Rotrex C38 that delivers in Kevin’s setup 7 psi.  We suggested a larger pulley to keep boost down to a very safe level.  However Kevin’s already thinking about having us install a smaller pulley to make 9 psi!  While we were at it we also added GTM’s AT Trans Cooler and Engine Oil Cooler to work with the SC kit.

Just a turbo driven by a belt 😉

We installed the kit on Kevin’s 2010 G37S Coupe AT.  Kevin already had an Invidia catback to add to the mix of mods.  We added a set of Fast Intentions HFCs since his ART pipes wouldn’t clear the new larger tranny cooler fittings and lines.

Believe it or not, this is where the intake sits since the blower sits low by the engine.  Sam claims and has done testing that inlet air temps aren’t as bad as they would look by having the intake sit right below the passenger exhaust manifold.

Quad cooler monster.  On the passenger side resides the trans cooler, top center the SC cooler (SC has its own oil system), below it is the intercooler, and on the driver side the engine oil cooler.

Nissan\Infiniti has made it hard(er) to service their automatic transmissions.  I can see how this would prevent the regular guy from using the wrong fluid and protecting the trans.  This is where you fill and check the fluid.  No dipsticks here!  Sorry Jimmy.

Installed and ready to make boost.  You can see the SC oil reservoir by the coolant overflow tank.

It’s hard to see what’s behind the bumper.  It’ll make you want to think twice when pulling up to a new G.

460 whp on 8.5 psi.  Time to light up the tires.


GTX-T28 Style

While perusing the new products @ SEMA 2011 we stumbled upon an interesting find.  You couldn’t find this at the main Garrett booth but we managed to do so elsewhere.  At first glance (a really quick glance) it looked like an ordinary GT2860RS.  As soon as we took a look at the compressor wheel and inner housing we knew we had a bird of a different feather.

From the back side not much to look at.

Utilizing Garrett’s new adjustable brackets for the wastegate actuator.  Not sure if this will be standard.

Holy cow Batman!  What do we have here!  The wheel is totally redesigned.  Much more of a straight blade design than what we’re used to seeing.  The standard 2860RS (T04B) housing now adds an anti-surge feature.  We can assume the wheel is 3mm larger besides being billet.  I was tempted to just slip this in my bag…. J\K!  I’d need a 2nd one anyway 😉

The is the compressor map differentiating between the new 2863RX and the 2860RS we’ve come to love.  If this is correct, this turbo can easily make 30+ psi of boost and do it efficiently.  This thing looks like it shits on the RS.  Let’s hope it comes out and translates to be as good in the real world as it does on paper!  I mentioned earlier that these needed to be burst tested but they actually do not.  They are ready to be sold and will be shipping out shortly!  I can only hope and wish they do this for the T25 flanged 30 series.

Some press release from Garrett:

Garrett® GTX wheels feature next-generation aerodynamics, fully machined from forged aluminum alloy. Each wheel is performance tested in stateof-the-art laboratories to insure the best design is used to deliver provable results without guesswork.

Garrett® GTX Turbochargers will be available in several new sizes including GTX2860R, GTX2863R, & GTX2867R.