Category Archives: TU Premium

Intake Manifold Tuning: Shifting the Torque Curve up and Down

When we talk about adding horsepower, what we're really talking about is adding torque (which is a measurement of power whereas horsepower is a measurement of power over a period of time). More specifically, we're usually talking about adding volumetric efficiency. In other words, if you want more torque at any given engine speed, all you need to do is increase the amount of air and fuel being burnt with each stroke at that speed. More horsepower naturally comes from adding more torque at higher and higher RPMs.


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Pressure/Flow Loss in Pipe Bends: Better to Go Long or Bend?

The other day I ran across a useful table in a very old and rare book on Air Conditioner design of all things. You may never have thought about it, but air conditioner ducts need to be relatively well flowing as well to minimize the size of the blower needed to get adequate cooling to the final location and in most cases the runs of ducting are VERY long relative to intake or charge piping for a turbo system.

There are several things that add pressure loss (restriction) to any pipe system, for the purposes of this article we'll focus on length and bends. It turns out that bends have the same effect as adding additional length. In other words, if I have two intake ducts that are 5' long but one is straight and the other has a 90 degree bend in it, the one with a 90 degree bend will flow as poorly as a straight pipe with a longer length. (more…)

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Ideal Exhaust Size for Displacement and Power

Size does matter, after all.

Over the years I've compiled data from various sources and personal tests to put together a chart of ideal exhaust pipe diameters. These diameters are of course only a starting point, but in my experience they have been pretty "bang on".

These diameters are specifically for "cat back" exhaust systems and are generally the best compromise between velocity and overall flow. John Grudynski, in an class I did with him for TU Premium members back a few months ago (Available Here: The Secrets of Header & Exhaust Design) talked about how he frequently achieves better results with relatively "small" exhaust systems and how he will occasionally use a "step system" on really radical street and race cars. The chart (a TU Premium exclusive) covers everything from 1.5L to 4.5L or so, both dual and single exhaust diameters, and various power outputs. Use this as a guide, then always test for absolute optimum results.

More information about how to use this chart, inside.


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Engine Tuning Secrets: Ben Strader of EFI University

This month I talked to Ben Strader, founder of EFI University and the author of two great books on tuning EFI systems and now also a Tuner University Certified Expert award winner . Ben's company EFI University is one of the top organizations teaching people from every walk of life from hobbyist to OEM engineer how to tune their engine from the ground up.

In this TU Premium class, Ben told us that engine tuning isn't a black art, it's simply a problem solving exercise and anyone with the proper training can do it. At the end of the day, Ben shared, tuning is about maximizing the airflow the engine can already flow and allowing the engine to remain reliable in its intended application. (more…)

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Engine Bloodwork: Benefits of Oil Analysis

Ryan Stark

Ryan Stark, Blackstone Labs

This month, I got on the phone with Ryan Stark of Blackstone Labs to talk about the most interesting topic in the world! OIL!

Well, okay, I'll give you that oil isn't terribly interesting but it is a vital fluid in our engines and one that is wrapped up in a lot of confusion, forum legend, and marketing bull. Matter fact, what's actually really interesting is what information out there is actually true, and what's complete and total B.S.

Ryan has been analyzing oil samples for over 15 years from pretty much every type of engine in existence. He's seen oil samples from airplanes, military vehicles, and nearly every passenger car or truck in existence. The people over at Blackstone have a massive database built from these samples so if there were ever an independent authority on which oil is best to use - he'd probably be it, if you ask me. Especially if your interest is in protecting your engine as best as possible. Ryan therefore is another one of our Tuner University Certified Experts.


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Are You Dense? Importance of Air Density in Making Power

Air is a combination of gasses, primarily nitrogen (about 78%), Oxygen (~20.95%) and to a much smaller extent Argon, CO2 and other trace elements.

All gasses expand when heated up, meaning that their molecules spread out and thus fewer molecules occupy the same amount of space. Thus, hot air has less oxygen and cold air has more. Today we're going to talk about how important air density is and how you can maximize your power production by paying close attention to charge temps. We're also going to look at how air density varies when under boost and when at atmospheric pressures and how temperature can actually cancel out boost - if it's not controlled!


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Header Design Secrets: Interview with John Grudynski of Hytech Exhaust

This past week I interviewed John Grudynski, the owner, artist, and innovator behind Hytech Exhaust.

John has been designing and building race headers for many major racing series and organizations such as SCCA, USAC, Trans-Am, World SportsCars, Dirt Track and NHRA Drag racing for nearly 30 years. He is easily one of the foremost experts on the "black art" of Header design and has an incredible reputation in motorsport and in the aftermarket.

John has also developed some seriously impressive aftermarket headers for cars such as the Honda Integra Type-R (which gained almost 20hp over factory), the Eclipse V6, the RSX Type-S and many more.

John also earns the distinction of being recognized as one of the Tuner University Certified Experts and the first to receive the honor. This honor is one given only to companies and individuals who have earned their stripes and demonstrated unique abilities and innovations in motorsport, OEM, and aftermarket parts/services.


Posted in Engine, TU Premium | 1 Comment