December 26, 2000

VE Spreadsheet Excel 2000

Fast Toys Ram Air
Does this system ram air or bull?

FTRA system under modified air box assembly

What is the Fast Toys Ram Air system?

The Fast Toys Ram Air (FTRA) system is installed on the front end of the air induction system on any LS1 F-Body. The largest part of the FTRA system is made up of T304 stainless ducting that directs air from under the front of the car in front of the air dam to the bottom of the air box assembly. The system uses the oldest modification to the LS1, the free ram air modification (!FRA). If you are on any website or with a group of LS1 friends, you will see that almost every F-Body has this modification. The bottom of the air box and the radiator shroud below are cut out to allow cool air into enter to the bottom of the air box.

On Fast Toys, Inc. website, they claim cooler intake temperatures and increased VE. Cooler temperatures and better VE will increase horsepower making the LS1 even more powerful. When this product came out, I could see how cooler temperatures would be produced, but it was the increased volumetric efficiency that got my attention.

How do you test for volumetric efficiency?

Finding out your car’s VE is not as hard as it sounds. In fact, calculating your car’s VE is relatively simple if you can work a calculator. I am not going to go into great detail surrounding the mathematical calculations used to arrive at the final results in this article. I have explained the procedure step by step in an article on my website, www.InstallUniversity.com, “Volumetric Efficiency: Calculating your car’s volumetric efficiency.”

A few simple items/conditions must be adhered to if you are to calculate your car’s VE. First, you must have a scan tool, such as Auto Tap, Tech II, etc., that will record readings from the power control module (PCM) on your car. Engine speed (rpm), mass air flow (lb/min) and intake air temperature (°F) are the only parameters that need to be logged. A stock mass air flow housing (MAFH), sensor, and screen must be used when recording the data parameters from your car. This is an absolute must because a ported MAFH or sensor will give inaccurate measurements.

The donor car

When this idea first crossed my head I had to get someone to help me out because I did not own the FTRA system. I made a few posts on the net after a few bombed attempts at receiving some help, I caught up with Dionne Aleman. Dionne was kind enough to run the test for us using her 1999 Trans Am. She has the FTRA system, auto tap, and the willingness to help. That made her a perfect candidate! Thanks Dionne! Be sure to check out her website, too! http://missthang.my50megs.com

Test procedure

This is the easiest and most fun part involved in testing your car. You have worked out the basis for your test, figured out what you will need, and now you get to have a lot of fun screaming down the racetrack all in the pursuit of knowledge. :-D Don’t get too happy, you have to do the math after your run for fun.

It is a good idea to make more than one run per condition when you auto tap your car. This ensures that any erroneous readings or a small screw-up is not a big deal. In this case, you would be making at least four runs; two when the system is not functioning (stock function) and two when the system is functioning.

Dionne’s Results

Table 1

Gear

Average Volumetric Efficiency (%)

Average Intake Temperature (°F)

1

80.1

97.0

2

84.1

96.7

3

83.2

92.7

Here is the part that is not so fun unless you have a spreadsheet set up to do the brunt of the work while you sit back and watch. I have done this once or twice so my spreadsheet was raring to go once I got the test results in.

The data was imported into Microsoft Excel 2000 and the numbers were crunched. Table 1 shows the results with the FTRA system not functioning. Table 2 shows the results with the FTRA system functioning. These are the averages of the results obtained with Auto Tap through each gear.

Table 2

Gear

Average Volumetric Efficiency (%)

Average Intake Temperature (°F)

1

80.1

86.0

2

85.0

84.6

3

84.1

82.3

The intake air temperatures from both tables were compared. The FTRA system immediately offered an eleven-degree Fahrenheit drop in intake air temperature. This is definitely a great effect of the FTRA. The engine will perform better with the cooler air. This idea is very similar to the !FRA modification. The duct that leads down in front of the air dam helps to keep out more unwanted heated engine air than the !FRA modification.

Nobody buys the FTRA system just because they are able to get cooler air to the engine. They buy the kit because they can get cooler air to the engine and increase the engine’s VE which results in more power. After analyzing the test results, it was easy to see that the FTRA system did increase the volumetric efficiency of the engine, which nets a gain in horsepower.

The test runs were made in the first three gears of a six-speed LS1. That puts the LS1 rifling along at 100 mph plus at the end of the test run, just like at the nearest quarter-mile drag way. In first gear, the VE showed no gain. During second gear, an increase of 0.9 percent was shown over the stock configuration. Third gear showed the exact same increase over the stock configuration. A 0.9 percent increase in volumetric efficiency stuffs an extra 31 cubic inches of air into the engine.

Equation 1

A 0.9 percent increase doesn’t sound that great. A typical LS1 with ported heads, cam, headers, etc., will gain a seven percent increase in VE (100 horsepower). This is very important to note. Assuming that the VE is directly related to the amount of horsepower added (on a natural aspirated LS1), a 1% increase results in a 10 – 15 horsepower gain (see Equation 1).

Quarter-mile track data backs up the conclusion that a 10—15 horsepower gain is reality. This reinforces the above-mentioned assumption, which is just that, an assumption, since I do not have any sources to back up that claim. Therefore, you might be able to test individual parts (i.e. aftermarket air lids, ported throttle bodies, etc.) before and after in order to see if they work for your car.

Use our spreadsheet to test your car

Do you want to test your car out but do not want to deal with the math or initial setup of the spreadsheet? Don’t worry, you can find a sample spreadsheet in Microsoft Excel 2000 format to use for your very own test. Just right click on the link below, click "Save As" and get started.

If your VE doesn’t match up exactly to Dionne’s VE keep this in mind that your car will not be the same as your buddies and the VE will change as the seasons change throughout the year.

Download Spreadsheet - VE Spreadsheet Excel 2000

Track and fuel economy results

I was very impressed with Dionne’s numbers so I decided to order the kit and install it on my car. I was pleased to see that I too received nearly identical gains from the kit. I was able to test the kit in fourth gear and received a 1.50% increase over stock.  Once the increase in volumetric efficiency had been confirmed, it was time to dismiss math class and head toward the drag strip.  After all, that is where the final decision is made.

Table 3
Gains
E.T. 0.073
MPH 0.456

Any day at the drag strip is a nice day as long as you are not breaking something, but a testing day always makes for a great time.  After many passes down the track testing out our kit, we sit down and averaged out the results.  Our local track is an 1/8th mile track so we miss out on a full run down the quarter mile but we still showed nearly a tenth and one half mph (see Table 3).  A one half mph gain in speed results in a nice 5 rear wheel horse power increase in the 1/8th.  This should be greater for those running the quarter mile because the VE would increase even more as you achieve much higher speeds.

The only thing more important then being the fastest you can be at the drag strip, is getting an increase in gas mileage from a part that helps you go faster.  After a day of driving on the interstate we ran the numbers on our gas receipts to see how much of an improvement would be had from the FTRA kit.  With the FTRA kit blocked off and not in use we average 26.5 mpg.  When the block off plate was removed and the front of the air box sealed off, we hit 28.1 mpg for a 5.7% increase in fuel economy.  This alone will pay for the kit within 3,000 miles of driving with gas prices as high as they are these days.

Test results reminder

Keep a few things in mind before quoting your measured VE results or mine as the gospel. First, the results are not set in stone. Be sure you make at least three runs of each test condition to make sure both runs look representative of each other. In other words, you are looking for repeatability rather than a one time occurrence. Second, this all hinges on the mass air flow sensor readings. The stock MAFH and sensor must be installed to obtain the most accurate readings possible.

Notice how the average is better suited to be looked at as a representative sample through each gear as opposed to pulling out random samples at a certain rpm. Random samples, (the condition at one selected rpm), can be high or low making the results skewed and misrepresentative of the data.

The last important factor to keep in mind is that the FTRA kit works better with an aftermarket air box lid.  The factory unit restrictive enough to hamper the full benefit the FTRA kit offers.

Customer reviews

FTRA duct to bottom of car

I have interviewed many owners of the FTRA system. Three main claims are heard over and over while interviewing FTRA owners. 1) One to two tenths second gain was achieved in the quarter mile. 2) better gas mileage and, 3) better throttle response. I am usually pretty skeptical about customer reviews. I believe if you look hard enough or just get the mental mod cap on, you will make yourself believe a coat hanger gives you five to seven horsepower. Track data and fuel mileage allow an independent decision to be made based on factual test data. This takes the butt-o-meter measurement that your buddy uses out of the mix.

FTRA concerns

I am not going to tap dance around the LS1s sucking up water through the !FRA modification. Although the instances I have heard about can be counted on one hand, Fast Toys, Inc. has done something very unusual. They have thought about that possibility and offer piece of mind to the consumer. Phillip Preddy at Fast Toys, Inc. tested the FTRA system using a power spray wand. While spraying the water under the front of the car directly toward the air dam, he was unable to get the air filter damp. Of course, this does not ensure a 100% guarantee that water won’t make its way to the air filter. This does reaffirm that water won’t easily travel up the ductwork.

While there has not been one report of any car sucking up water with the FTRA system in use, this doesn’t mean it cannot happen. In fact, one day I am sure it will happen to some one along the way.  I have learned many times that “it” happens every now and again. Phillip added a block-off plate that you will use for two reasons: 1) use the block-off plate when driving in the rain to keep the rain water off the air filter and, 2) use the block-off plate to stop the function of the FTRA system, returning the air intake path to stock. Using the block off plate will allow you to have piece of mind driving the rain and perform your own volumetric efficiency test.

Final thought

A one percent increase in volumetric efficiency does not seem significant when talking about serious power adders (ported heads, cam, turbos, etc.). Remember that this is a basic bolt-on and one percent is very respectable and represents a 10 - 15 horsepower gain with this system at the track or on the street. The kit is well built and relatively easy to install. You have to be sure to seal the kit extremely well to gain the most you can from it.  When compared to other parts that claim the same gains for more money, the FTRA system looks better all the time because it backs up its claim for a fair price. I would not hesitate recommending this modification to any LS1 F-Body owner. Like I mentioned earlier, Dionne’s test results persuaded me to purchase the kit for my 1999 Z28. :-)

Works Cited

  1. Fast Toys, Inc. http://www.fasttoys.net
  2. Deskins, Tom.  Interview.
  3. Aleman, Dionne. Interview and data collection.
  4. Vizard, David. How to Build Horsepower. Volume 2.
  5. Green, Don, and Robert H. Perry.  Perry's Chemical Engineers' Handbook.  6th edition.  New York:  McGraw-Hill, 1984.

- Eric Barger

 

Editor:  Kelly Barger
Photography:  Eric & Kelly Barger

Web Author: Eric Barger  help@installuniversity.com
Copyright © 1999 - 2002  Eric Barger.  All rights reserved.
Revised: June 07, 2007.