Tech Guide - Throttle Body

 

BBK Performance have been the premier manufacturer of Power plus series throttle bodies for over 25 years now and people ask why we do not repair throttle bodies or sell individual components for them. There are a couple of big reasons:

1. During this time materials, designs and specifications have changed and been improved. 
2. With the change in specifications and components, nearly all of the newer components will not fit older previous model throttle body castings anymore and we can longer source these components to the spec of older throttle bodies.
3. We do not repair or sell components is because we measure every CNC machined throttle body casting and the components are matched to fit.
4. This includes THE most important part – the throttle blade – Each throttle body bore is measured with a CMM machine to ensure quality – then every throttle blade is individually measured, beveled and spec’d to be an exact match for each individual throttle body bore to within thousands of an inch.

Due to liability, on-going design/manufacturing process updates, and the multiple special assembly fixtures that are required to assemble BBK products properly, we do not offer rebuild or repair parts for these types of products. With this in consideration, we can offer our valued BBK customers a discount on new replacement units. Please email sales at bbkperformance.com for more details.

 

Hunting for idle (surging) can come from a few issues. All of which allow the idle to dip too far which causes the ECU to attempt to overcome. This starts a cycle. Check the following areas for an idle surge issue:

• Vacuum leak
• Low idle speed 
• Insufficient ground connection
• Low alternator output voltage 
• Dirty or faulty MAF
• Dirty or faulty injector(s)
• Mismatched MAF/injectors
• Dirty or faulty IAC
• Low fuel pressure

 

(Parts possibly affected: 1776, 1767, 1722, 1723, 1791, 1792, 1700, 1701, 1780, 17800, 17801, 1705, 1711, 17110, 1652, 1552, 1522, 1523, 1524, 1548, 1500, 1600, 1517, 1501, 1503, 1514, 1715, 1755, 3501, 3503, 3502, 1703, 1580, 1751, 1754, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1709, 17090, 1710, 1547, 1724, 17240, 1783, 1784, 1791, 1792)

Note: If your part is not listed above, please call our tech line - 386.624.0025

BBK’s cable driven throttle bodies come with an adjustable “throttle stop screw”. This screw is the last point the throttle bodies linkage contacts, keeping the throttle blade from closing anymore. If the throttle bodies blade closes completely you’ll get some vacuum pressure built up behind the blade causing the blade to delay slightly before opening. The best way to alleviate this is to simply rotate the throttle stop screw towards the linkage a few turns. This will keep the blade from closing completely and will also eliminate any delay. Once you’ve opened the blade slightly, you should be able to fine tune the throttle stop screw to achieve your desired idle. 

 

Note: If your part is not listed above, please call our tech line - 951-296-1771 

The first thing you’ll want to check is does your vehicle have an aftermarket performance tune installed on the ECU? Aftermarket tunes installed on the vehicles computer can sometimes keep the engines computer from making proper changes to adapt or adjust to the new BBK throttle body. 

First thing to do is to "re-install the factory tune" back to ECU from your programmer, then reinstall throttle body and drive the vehicle to insure no check engine light comes on again. 

If no check engine light appears, re-install your aftermarket tune from the programmer and you are good to go. 

Please be sure to follow all BBK instructions when installing the throttle body.

(Parts possibly affected: 1781, 1782, 1822, 1821, 18210, 1763, 1764, 1765, 1823, 1758, 1759, 1789, 1790, 1708, 1756, 1757, 1766)

 

This condition is sometimes known as "vacuum lock." There is an extreme amount of vacuum pressure on the backside of the plate, and a large pressure difference from that of the front side. When this happens, the throttle blade tends to want to stay in the closed position, due in large part to the intense vacuum pressure created by the engine. Simply using the Idle set screw (gold colored screw which the linkage rests against) to prop open the blade a tiny bit more will usually solve the problem by allowing more air to pass through the opening, thus better equalizing the pressure and alleviating the "lock." Remember to do small increments at a time, ¼ to ½ turns each attempt.

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)

 

Turbulence in the airflow stream can create a whistle. This can be created by sharp edges in the air intake system, most notably when a larger throttle body is used on a stock intake that has not been 'Port Matched.' The air along the outer edges of the air intake system and throttle body hits the "wall" of the smaller intake manifold, creating turbulence that can cause a noticeable whistle. Other trouble areas can be the small vacuum ports and the IAC (Idle Air Control) valve port which may empty into the main bore of the throttle body. If these edges are square enough at the entry point of the bore, it can create turbulence, and the air will whistle passed it (similar to blowing over the top of an empty cola bottle just right to get it to whistle). 

If you feel you are adept enough with simple hand tools, you may want to try and hone the ports yourself with fine grit sandpaper. Some customers use a small drill or Dremel-type tool to lightly sand the edges down. Be aware though, that any irreparable damages done to the product on the customers behalf cannot be warranted by BBK. Be aware though, that further honing the throttle body may not cure any whistling issues if the problem actually lies elsewhere in the system, and if the added airflow of a larger-bore throttle body is only making the problem perceptible.

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)

 

Not necessarily. Many times, our throttle body designs will encompass many different models, some of which use slightly different connections than other models. This is especially true of automatic cars versus manuals. If you find that you have arms and cable connections that you simply have no use for, you may safely ignore them!

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)

Not necessarily. Here at BBK, we have discovered that some of the basic design characteristics of our throttle bodies carry over to a large number of models. In order to offer as many enthusiasts as possible a choice for performance throttle bodies, we have gone the extra mile to add certain connections to them that are required for some applications, though perhaps not yours. If this is the case, you must cap off the remaining vacuum ports, so as to avoid possible vacuum leaks that could be detrimental to your performance.

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)

Some of the throttle bodies work for many different models. On some of those models, you may experience a situation where the pedal seems to sit lower. Have no fear; the throttle body is operating to its full capacity. You can verify this by having someone push down on the throttle and then check to see that the throttle butterfly is at WOT (Wide Open Throttle). So long as you can achieve the full range of butterfly movement from idle to WOT, there should be no problems.

(Part numbers affected include: 1700, 1701, 1703, 1705, 1711, 17110, 1755)

The holes in a stock throttle body are there to help fight a situation known as "vacuum lock." When the blades are closed almost fully, and very little air is allowed to creep through, you wind up with a large difference in pressure between the front side, where it is about the same pressure as the atmosphere, and the backside, where the motor is creating a large vacuum against the butterfly. This tends to lock the blade into place. Since the stock throttle body is so much smaller than BBK's, it is much more of a dilemma, requiring holes in the butterfly to allow more air to flow passed, equalizing pressure. Since the BBK throttle body is a bit larger, it tends to flow more air passed its opening, thereby avoiding the need for the holes.

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)

If you are putting it on a truck, then the answer is most likely yes. However, if ever in doubt, always check and compare against your stock set up. BBK throttle bodies are designed to replace the OEM units and utilize all of the same components and functions. If your stock system utilizes that particular port, then it is recommended that you not block it off, as it could adversely affect your performance and idle quality.

(Part numbers affected include: 1705, 1711, 17110, 1755)

 

Most likely it is the correct part. We have discovered that the basic design of our throttle bodies will work for a large number of models. In order to offer a choice in after market performance throttle bodies to as many enthusiasts as we can, the coolant lines were put where we thought it made the most sense; right in the middle! Thus, if you find that the coolant lines do not point where you would like them to, you may want to consider LIGHTLY bending them to the direction you desire. The metal is pretty soft, so it it should bend in the direction you point without problem. The best way to attempt it is to take a small diameter deep-well socket (not much bigger than the tube) and place it over the line to be bent. But be careful! BBK cannot warranty irreparable damage incurred by the user. As an easier and more performance-beneficial workaround, you can just bypass the coolant lines. BBK recommends this fix as it will keep the hot coolant away from your intake system, helping keep your air intake stream cooler, thus increasing performance.

More than likely nothing is wrong with the piece. The stock design is very exacting, working with very tight tolerances in consideration of the stock throttle body. However, since the throttle body places the blade so close to the intake manifold, when going to a larger throttle body, you must port the intake in order to allow for clearance of the new, larger blade on the BBK unit. 

You can either port just the edges where the throttle blade catches, or BBK recommends that you port the entire surface to match, as this will allow you to achieve maximum flow and power potential from your new piece.

(Part numbers affected include: 1548, 1552, 1652)

Though the TPI and LT-1 throttle bodies do have a similar basic body structure, the linkage systems and the TPS (Throttle Position Sensor) are different and incompatible.

(Part numbers affected include: 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544)

Unfortunately, at this time BBK does not support the automatic transmission-equipped Focus. If you have a Focus with an automatic, you should return the part to the dealer where you purchased it for a refund.

(Part numbers affected include: 1751)

On today's modern computerized cars, there are usually a few components that are at least partly responsible for the operation of an automatic transmission. On some models, the computer controls the shift points by comparing the mass air voltage versus the TPS voltage, and makes the determination for gear choice. Some also monitor the manifold pressure and utilize the readings found there to make the correct gearing choice. Some use both! If you have an automatic-equipped car and are suffering from some shift-point-blues, there are some things that you can do.

One quick and easy way that sometimes proves successful is to modify the TPS voltage. If you bring the TPS voltage up a little bit, it will more closely fall in-line with what the computer expects to see as far as voltage readings between it and the mass air meter. You must do this in small increments, though: If the TPS is adjusted too high, it can create its own set of problems, like an erratic idle or slightly declined performance.

Another thing to try is to put some smaller vacuum tubing on your manifold/throttle body. After installing a larger-bore throttle body, you can expect manifold vacuum pressure to drop a bit. This is due to the fact that you now have a larger opening to the outside atmosphere, and more flow. This option may prove to be a more tedious process than it is worth, however. Another option you might want to consider is the purchase of a "Tuner Chip" or programmer. Most after market computer chips come equipped with various ways to adjust certain settings on your car. Not only will they usually help the tune of your engine, but many will allow you to access the shift point settings, and modify the shifts to what you want them to be, and Where you want them to be. Some applications will really benefit from this add-on, even if only used for its transmission tuning capabilities. 

You must be aware, though, that your car's ECU (Engine Control Unit) needs to be fully calibrated for your throttle body prior to installation of any computer chips. Some chips work by modifying the stock program for better performance - and if the stock program has not yet compensated for the after market throttle body, then your added programming configuration will not function properly on your car. You could find that your idle quality and performance will not be up to par, and you may in fact run into some issues.

(Part numbers affected include: 1501, 1503, 1514, 1517, 3501, 3502, 3503, 1534, 1536, 1537, 1539, 1540, 1542, 1543, 1544, 1522, 1523, 1524, 1715, 1700, 1701, 1703,1580, 1705, 1711, 17110, 1755, 1708, 1709, 1710, 1721, 1756, 1757, 1546, 1547, 1752, 1753, 1751, 1754, 1548, 1552, 1652, 1723, 1716)