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7 <meta name="Description" content="Article for February 1999 issue of the Santa Clara Corvettes Newsletter">
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8 <title>Getting the Most Out of Your Gears</title>
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14 <font face="Arial,Helvetica">Getting the Most Out of Your Gears</font></h1></center>
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18 <font face="Arial,Helvetica">By <a href="mailto:fans@3dfxcool.com">Bart
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19 Lane</a></font></h3></center>
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21 <center><i><font face="Arial,Helvetica"><font size=-1>This article was
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22 edited and adapted to the web by <a href="/">Andrew
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23 DeFaria</a></font></font></i>
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24 <br><i><font face="Arial,Helvetica"><font size=-1>from a posting by Bart
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25 Lane to the newsgroup <a href="news:alt.auto.corvette">alt.auto.corvette</a>
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26 with his permission</font></font></i>
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27 <p><a href="http://www.c5registry.com/Technical/Bart/index.htm"><img SRC="http://www.c5registry.com/Members/Mempages/Pics/blane.jpg" ALT="Bart Lane's C5 - Click photo to see other articles by Bart" BORDER=0 height=185 width=320></a><i><font face="Arial,Helvetica"><font size=-1></font></font></i>
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28 <p><i><font face="Arial,Helvetica"><font size=-1><b>Note: </b>This article
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29 is also available at <a href="Gears.html">http://www.defaria.com/Gears.html</a></font></font></i></center>
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32 <hr SIZE=1 WIDTH="100%">
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34 <font face="Arial,Helvetica">Automatic versus Manual</font></h2>
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35 <font face="Arial,Helvetica"><font size=+1>Having an automatic transmission
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36 can sometimes be a burden. Sports car enthusiasts, including other Corvette
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37 drivers, will shun on you for getting the slush box over the stick. People
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38 have automatics for many reasons, some of which are convenience, cost,
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39 availability, and driver skill level. It is not easy to drive a manual
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40 transmission fast. Not just anybody can hop into a six speed and make it
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41 faster than the auto. In fact, I would be willing to wager that most six-speed
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42 drivers out there can be beaten stop light to stop light by most auto drivers.
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43 It is a fine art and takes much practice to master driving a manual transmission
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44 efficiently. It can be done though and, in identical cars with perfect
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45 drivers, the manual transmission will be faster than the automatic in every
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46 circumstance. Do you drive an automatic? How would you like to turn this
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47 around so that your car is faster and quicker than every six speed out
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48 there? We can turn our weaknesses into strengths and leave every six speed
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49 in the dust. Not to mention this will also make your automatic much, much
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50 quicker and I can not think of a better bang for the buck.</font></font>
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51 <p><font face="Arial,Helvetica"><font size=+1>Six speed transmissions are
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52 faster for one reason: they rob less horsepower from your engine. Manual
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53 transmissions have parts that positively mesh and interlock such as dry
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54 clutches and gear teeth while automatics replace these parts with fluid
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55 driven hydraulic torque converters and wet clutch packs. You are just going
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56 to get more power to the rear wheels with a stick and there is nothing
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57 you can do to reverse this.</font></font>
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59 <font face="Arial,Helvetica">Improving the Performance of You Automatic
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60 Transmission</font></h2>
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61 <font face="Arial,Helvetica"><font size=+1>What we can do already is to
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62 make the transmission work better with the engine and allow the automatic
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63 transmission to start working when the engine reaches its power band. This
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64 is done with a looser stall converter. I could write paragraphs and paragraphs
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65 trying to explain converters to you but the truth is they still remain
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66 somewhat shrouded in mystery to me. The company who built my converter,
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67 <a href="http://www.protorque.com">ProTorque</a>
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68 (<a href="http://www.protorque.com">http://www.protorque.com</a>), also
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69 has a tremendously informative site up with lots of facts. There is no
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70 greater HP value than the stall converter in the land of hot-rodding. I
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71 chose a 2900 rpm stall converter and it was $650 delivered from <a href="http://www.proautotech.com">Pro
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72 Auto Tech</a> (<a href="http://www.proautotech.com">http://www.proautotech.com</a>).
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73 The claim is ½ second better time in the quarter mile. No other
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74 upgrade can compete with this for the money.</font></font>
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75 <p><font face="Arial,Helvetica"><font size=+1>In a nutshell, the after
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76 market torque converter is more efficient and takes less power to operate
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77 which means more power to the rear wheels. Its primary strength however
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78 is that it doesn't begin to transmit power to the transmission until the
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79 engine is in its power band. An engine revs faster and more easily in neutral.
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80 Imagine revving a motor up to 2500 rpm or so in neutral and then dropping
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81 the shifter into drive.</font></font>
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82 <p><font face="Arial,Helvetica"><font size=+1>Wouldn't this method leave
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83 quicker than just flooring it while in gear? Of course you wouldn't do
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84 this because it can damage the transmission and you have to wait for the
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85 gears to engage using this method anyway which takes time. The looser stall
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86 converter can simulate this while you are in drive already by not transmitting
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87 power, when the gas pedal is floored, until the engine comes up within
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88 its strong area.</font></font>
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89 <p><font face="Arial,Helvetica"><font size=+1>Why donut the car companies
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90 do this to begin with? Well, there are issues with driveability and fuel
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91 mileage. I will cover all driveability issues later in this article and
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92 fuel mileage is iffy. Newer cars have computers that can physically lock
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93 up the torque converter. This is desirable when full engine power is being
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94 delivered to the transmission so the converter stops depending on fluid
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95 to turn itself but has real time positive mechanical lock up. This is much
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96 more efficient than fluid driving the car.</font></font>
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97 <p><font face="Arial,Helvetica"><font size=+1>I put a 2900 rpm converter
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98 on my car which means that the converter will not lock up until the engine
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99 reaches 2900 rpm. So, my car is being driven by fluid until it hits that
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100 engine speed. But, do you drive on the highway at 2900 rpm? I hope not,
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101 you would be going well within ticket range. So, if my torque converter
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102 is not locking up at freeway speeds and my rear wheels are being driven
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103 by transmission fluid isn't that less efficient and wont my mileage be
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104 terrible?</font></font>
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105 <p><font face="Arial,Helvetica"><font size=+1>This is the concern but we
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106 live in the end of the twentieth century and enjoy computers and their
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107 benefits in every aspect of our lives including automobiles. Your computer
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108 knows that you are traveling at freeway speeds regardless of RPM and tells
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109 your transmission to lock up that converter for positive power delivery
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110 from engine to transmission with no loss. Problem solved.</font></font>
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111 <p><font face="Arial,Helvetica"><font size=+1>There are still some very
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112 real concerns about around town driveability with a higher speed stall,
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113 which I will discuss at the end of this piece.</font></font>
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115 <font face="Arial,Helvetica">Shift Kits</font></h2>
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116 <font face="Arial,Helvetica"><font size=+1>Next modification in the drive
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117 line is the shift kit. This kind of gets me in a tizzy because I made a
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118 mistake. I ignorantly confused shift speed with shift firmness and permanently
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119 installed the wrong part in my car. The part I am talking about is the
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120 B&M Shift Plus computer shift firmness selector. The <a href="http://www.hypertech-inc.com/main.html">Hypertech
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121 Power Programmer</a> (<a href="http://www.hypertech-inc.com/main.html">http://www.hypertech-inc.com/main.html</a>)
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122 shift firmness section does the same thing.</font></font>
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123 <p><font face="Arial,Helvetica"><font size=+1>Shift firmness is internal
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124 transmission line pressure and that's what these devices control too. They
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125 can firm up the shifts, but not speed them up. My question is why bother?
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126 The PCM gives you maximum shift firmness at wide open throttle (WOT) anyway
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127 which is really the only time you need the boost. These devices fool the
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128 transmission into thinking you are at WOT no matter what speed you are
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129 at and thus give full firmness at lower speeds. This means nothing and
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130 doesn't help performance. It merely makes your butt feel like your car
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131 is going quicker at lower speeds than it really is. Useless for performance,
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132 donut waste your money if that is what you are going for.</font></font>
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133 <p><font face="Arial,Helvetica"><font size=+1>What you <b>want</b> to do
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134 is to speed up your shifts. When a transmission shifts gears it remains
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135 in two gears at once for a short time to give smoothness to the shifts.
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136 This has two downsides though, it increases wear and slows you down. The
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137 only way to speed up your shifts is to add a real shift kit. This involves
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138 removing the transmission pan and the valve body to install new springs,
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139 balls, gaskets, plates, etc. This is the only way to go if you want to
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140 beef your transmission up for better performance. The only company I would
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141 think of getting a shift kit from is TransGo. They are the best and I have
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142 never seen a reason to switch brands. I got the TransGo shift kit
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143 for my year (94-99) and it cost me $130. This is a great thing to do to
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144 any automatic regardless of other modifications. You will experience crisper
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145 shifts, lower transmission temperatures, and a faster car.</font></font>
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146 <p><font face="Arial,Helvetica"><font size=+1>Automatic transmissions on
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147 the C5 are stifled with two gear choices. One is so lame that it doesn't
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148 belong on your Granny's Buick and the other is barely adequate. The two
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149 gear ratios in order of descending suckiness are 2.73 and 3.15 If
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150 you have the 3.15 this upgrade may not be worth the money since that ratio
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151 is almost getting within respectable gearing. But if you have the 2.73
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152 in your car like I do please read the following section closely because
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153 this final drive ratio is not good for anything other than saving gas.</font></font>
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154 <p><font face="Arial,Helvetica"><font size=+1>The six speed cars have a
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155 ratio of 3.42, which is OK but still not what I like. I would prefer a
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156 3.73 in an automatic and the 4.11 in the six speed. Unfortunately,
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157 the best ratio available (Even though this is a higher number it is considered
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158 a lower gear.) is the lower 3.42. This will make a big, big difference
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159 over the 2.73 gear but may not be worth the money for you performance axles
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160 owners.</font></font>
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161 <p><font face="Arial,Helvetica"><font size=+1>Unlike the C4 Corvette, the
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162 C5 uses identical rear differentials, or carriers, for both the manual
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163 and automatic transmissions. This means you can just bolt up the whole
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164 factory loaded six speed carrier to your automatic transmission and get
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165 instant performance. Gains to expect? On my 94 I went from stock converter
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166 and performance axle to 2400 stall speed converter and 3.73 gears and got
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167 .8 seconds faster in the quarter.</font></font>
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168 <p><font face="Arial,Helvetica"><font size=+1>On this car I am doing taller
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169 3.42 gears but a higher stall speed of 2900 rpm so I hope to get similar
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170 gains. This would make it easily a 12 second car and who knows with good
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171 tires. This kind of speed does not come cheap.</font></font>
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172 <p><font face="Arial,Helvetica"><font size=+1>Buying the carrier? I called
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173 every after market tuner there was and these things were just too expensive.
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174 Then I called the Chevy dealer direct and told them I had a business license
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175 and wished to buy a part at wholesale. I told them what I wanted and got
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176 20% off list. My cost was $800!!! Nearly half of what the after market
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177 guys wanted. This is a tremendous value.</font></font>
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178 <p><font face="Arial,Helvetica"><font size=+1>You will need something to
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179 recalibrate the speedometer though. I suggest picking up the Hypertech
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180 Power Programmer for $300 since it can let you reprogram for the lower
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181 gear ratio.</font></font>
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183 <font face="Arial,Helvetica">Fluids</font></h2>
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184 <font face="Arial,Helvetica"><font size=+1>We are almost done with the
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185 parts here but I want to talk a bit about fluids, lubrication, and cooling.
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186 I am going to sum this up quickly, Redline makes the best lubricants as
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187 far as I am concerned. They have a great history in racing and their dyno
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188 reports show power gains with their products. I am using Redline D4 synthetic
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189 ATF in the transmission and 75/90 synthetic in the differential. I also
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190 use Redline 5w-30 synthetic in my engine. I also added a fluid made by
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191 Fluid-Gard called ATF Enhancer which, beyond many other claims, reportedly
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192 lowers transmission temperatures. I have heard some third party endorsements
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193 that did observe ten degree drops in operating temperatures. The higher
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194 speed stall converter can cause higher temps to occur which is why
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195 this is important. I also added a large, dedicated transmission cooler
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196 to my car. It looks like a little radiator and is mounted in front of the
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197 radiator up front. Between the cooler and the Fluid-Gard my ATF temperatures
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198 should well within safe range.</font></font>
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200 <font face="Arial,Helvetica">Installation</font></h2>
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201 <font face="Arial,Helvetica"><font size=+1>Now we are ready to discuss
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202 the install, or lack there of. I hashed it over and over in my head if
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203 I should put these parts in myself. I have a pretty solid automotive technician
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204 background and I know I could put them in the thing is I just didn't really
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205 want to put them in.</font></font>
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206 <p><font face="Arial,Helvetica"><font size=+1>After thinking it over I
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207 realized that I would be better served finding an experienced guy to put
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208 the parts in for me. My search was on. I looked high and low within
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209 an 800 mile radius of my home to find a seasoned person. In the end the
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210 guy for me was less than an hour from my home. His name is Paul and he
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211 works for Roy Robinson Chevrolet. His love for cars, technical repair,
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212 and Corvettes really shines when you talk to him. He begged me to bring
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213 the parts in the Friday before I dropped the car off so he could look them
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214 over and read all the literature over the weekend, <b>on his time!!</b>
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215 That was great and really showed he was dedicated to doing a good job.
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216 He has C5 Corvette experience and is the main transmission guy for this
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217 dealership. I really liked him and trusted him right off the bat. This
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218 doesn't happen to me all that often so I took it as a signal to go with
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220 <p><font face="Arial,Helvetica"><font size=+1>Also, they gave me a firm,
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221 reasonable estimate of ~$900 total labor. No other place would even talk
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222 estimates. This is about the only time I have ever felt good about dropping
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223 my car off at the dealership for repairs.</font></font>
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225 <font face="Arial,Helvetica">The Results</font></h2>
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226 <font face="Arial,Helvetica"><font size=+1>How fast is it and how does
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227 it drive? Can you now beat that little punk who has been terrorizing you
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228 in his Supra Turbo and embarrassing you day after day after day?</font></font><font face="Arial,Helvetica"><font size=+1></font></font>
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229 <p><font face="Arial,Helvetica"><font size=+1>When I picked the car up
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230 it was raining. Not just a regular Seattle rain either but a freak torrential
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231 downpour that made driving this new found power down right scary. I only
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232 got on it once on the way home. Two lane blacktop, straight and no cars
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233 in sight. I barely got into the pedal when the car lost it. I looked over
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234 and saw that the tail end was in the oncoming traffic lane and I was sliding
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235 sideways down the road. I was going 40 when I pressed it too. Fortunately
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236 it is hard to upset the demeanor of the C5 even with an act of stupidity
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237 like my own and a quick flick of the wheel and the release of the throttle
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238 brought me right back in line and I went home slowly the rest of the way.</font></font>
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239 <p><font face="Arial,Helvetica"><font size=+1>To look at the bright side
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240 I was basically thrown into a den of tigers with this level of performance
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241 and such poor weather. I was able to observe driveability under the worst
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242 possible circumstances. I was mostly worried about how this thing would
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243 drive day to day but let me tell you, if anything it is better. There is
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244 really no decrease whatsoever. It feels different but not worse. I know
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245 now that this modification had all benefits and no negatives other than
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246 cost.</font></font>
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247 <p><font face="Arial,Helvetica"><font size=+1>I was also worried a bit
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248 as to how hard it would shift. In a nutshell TransGo gives you four choices
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249 on the shift kit 0 to 4, 0 being basically stock (faster, but no firmer)
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250 and 4 being full race. I chose one because I drive on the streets most
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251 often by far. The 1 to 2 shift is very firm, you can feel a kick in the
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252 booty when it changes but the feel is very solid and purposeful. The other
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253 gear changes are less severe but still more firm than stock. All shifts
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254 are faster by far. I can set off the traction control going from second
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255 to third now.</font></font>
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256 <p><font face="Arial,Helvetica"><font size=+1>When stopped you can take
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257 your foot off the brake and the car will not move forward if there is an
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258 incline at all. It will creep forward ever so slowly if the ground is level.
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259 You press the gas normally and the car drives off smoothly without jerkiness
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260 or high revving power antics. The gear shifts, other than being firmer,
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261 change quicker enough than you can tell, and you are on your way with little
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262 fanfare. The gears are quiet and 60 mph happens at 2000 rpm even. Mileage
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263 drops about 2-3 gallons because of the gears but maybe that's because I
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264 am flooring it more often to force a grin on myself and a look of terror
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265 on my passenger's mug. Power is addictive as the saying goes. If you drive
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266 an auto I sure wish I could take you for a ride in my car because you would
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268 it!</b> I do.</font></font>
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270 <font face="Arial,Helvetica"><font size=+1>Out of the Rain</font></font></h3>
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271 <font face="Arial,Helvetica"><font size=+1>OK, lets talk about some dry
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272 roads and some sunshine. Mother Nature Seattle gave us one nice day last
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273 week and I took advantage of it the best I could. Lets sum it up this way:
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274 when this car hooks up it is unbelievable. Getting traction is a big trouble
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275 because when you floor the car now it seems as if the motor immediately
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276 jets up to 3000 rpm and the power is delivered then. A 3000 rpm neutral
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277 drop or power brake if you will. This will liquefy your tires and put on
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278 a nice smoke show for the kids. You can feather this with a less aggressive
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279 pedal input but I shudder to think how fast this car would launch if the
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280 rubber were up to the job. With practice the task comes down to sitting
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281 there, one foot on the gas and one on the brake, holding revs about 1200.
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282 When you want to go just plop your foot off the brake pedal and gently,
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283 ever so gently, press the throttle to the floor. This will take the car
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284 off with a chirp. It cant be floored too quickly though because the tires
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285 will lose their composure again in the one-two shift so let up a bit here
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286 and let it get into the new gear and then floor it. The tires will give
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287 up a bit of traction during the 2-3 gear change and perhaps a bit of a
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288 fishtail but it is not bad enough to warrant a lighter throttle application.
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289 The rest is just steering.</font></font>
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290 <p><font face="Arial,Helvetica"><font size=+1>Once this is practiced you
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291 can rocket this car to 100 mph in no time at all. It pulls fast and strong
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292 the whole way and is easily the most powerful car I have ever driven or
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293 even ridden in. I haven't been to the track yet so I will save the numbers
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294 for the spring, I am quite sure they will be very impressive.</font></font>
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295 <p><font face="Arial,Helvetica"><font size=+1>The search begins for adequate
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296 tires. I need some good drag tires for the track.</font></font>
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297 <p><font face="Arial,Helvetica"><font size=+1>That's it for preparing the
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298 car for more power. We have a beefy brake system, good handling, and a
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299 great drive train. When you read the next piece the hood will be
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300 up and well see what kind of power you can make in your garage with a set
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301 of tools. Have to go for now, its Supra hunting time.</font></font>
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303 <p><font face="Arial,Helvetica"><font size=+1><a href="http://www.geocities.com/MotorCity/7333">Back
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304 to Santa Clara Corvettes</a></font></font></center>
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306 <hr SIZE=1 WIDTH="100%">
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307 <center><i><font face="EngraversGothic BT"><font size=-1>Copyright ©
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308 1999 <a href="mailto:fans@3dfxcool.com">Bart Lane</a></font></font></i></center>
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310 document.write ("<center><font face=\"EngraversGothic BT\" size=-1><i>Last updated: " +
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