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...continued
from page 2
Later that year the car went through its biggest transformation yet. I had a set of used Vortec heads installed with the SDPC Vortec TPI base, a set of Edelbrock T.E.S. shorty headers and custom made y-pipe. I also had some chassis work done, namely sub-frame connectors, boxed lower control arms and panhard bar, a reinforced torque arm and lower control arm relocation brackets. Along with that I had a custom shift kit and a stock higher stall Corvette torque converter installed.
By this point I was big-time into custom tuning my setup, and using data acquired through the cars ALDL diagnostic port hooked up to my laptop, I was able to determine the impact of changes I was making to the engine. Through my butt dyno I was able to feel the differences made to the chassis. Off to the track I went:
| 60
foot |
1/8
mile |
1/4
mile |
MPH |
| 2.229 |
9.272 |
14.348 |
99.555 |
| 2.189 |
9.147 |
14.219 |
99.69 |
| 2.209 |
9.23 |
14.325 |
97.819 |
| 2.118 |
9.094 |
14.18 |
99.233 |
| 2.191 |
9.195 |
14.292 |
99.239 |
Wow! Over 99 MPH! That’s a direct increase of another 50 HP just from stock unported Vortec heads. The track prep was terrible and yet I was able to hook better then before even with the increased power I was putting to the ground, so the chassis and suspension work paid off as well.
I decided to return immediately to the track the following Saturday to test the car with better track prep. The runs above were on a Wednesday night and track prep was non-existent. Saturday yielded some great times:
| 60
foot |
1/8
mile |
1/4
mile |
MPH |
| 2.246 |
9.23 |
14.334 |
98.601 |
| 2.067 |
8.931 |
13.941 |
99.336 |
| 2.029 |
8.941 |
14.019 |
98.743 |
| 2.0 |
8.937 |
14.018 |
98.799 |
| 1.938 |
8.775 |
13.783 |
99.458 |
| 2.001 |
8.926 |
13.992 |
98.993 |
| 1.928 |
8.833 |
13.899 |
97.929 |
| 1.986 |
8.925 |
14.011 |
98.292 |
The first run was early in the test & tune session so we should disregard it. As the track was getting stickier and I was getting better at launching this torque beast the ETs were dropping. The best run of the day yielded a 13.78@99.46 mph but the elusive 100 mph trap speed was yet to be achieved. Nevertheless I was very happy with these times.
The car had truly become a competitor amongst the latest offerings from the automotive world. It also handled better with new KYB struts and shocks, got better gas mileage with the new heads, exhaust and a set of new 24lb injectors. Overall the car was very well balanced and quick, yet maintained an entirely OEM feel with its stock cam, intake system and gears.
I returned to the track again after installing a set of ported TPI runners and an SLP cold air box. The car felt faster to me and the ALDL data I analyzed showed me I was making more power but the track results are the only ones that count:
| 60
foot |
1/8
mile |
1/4
mile |
MPH |
| 2.283 |
9.159 |
14.13 |
100.156 |
| 2.354 |
9.3 |
14.269 |
99.697 |
| 2.33 |
9.24 |
14.208 |
100.234 |
| 2.283 |
9.172 |
14.175 |
99.677 |
| 2.285 |
9.201 |
14.161 |
100.524 |
Even though ETs were slower, this was a Friday night so track prep again was non-existent; the car yielded 3 runs at 100 mph. Conclusion: SLP cold air package was worth 10 hp, porting the runners maybe another couple.
2004 didn’t see any new modifications, but the one time I went to the track early in the year, I was pleasantly surprised with some killer times. It was April 24, 2004 and the wind was blowing hard. It was a cool Saturday, the track was well prepped, and I was trying a set of 275/60/15 BFGoodrich drag radials for the first time. The combination of the wind and the taller tires dropping my gearing was a huge improvement over the last track session 6 months earlier. Here were my best times to date:
| 60
foot |
1/8
mile |
1/4
mile |
MPH |
| 2.026 |
8.685 |
13.543 |
103.087 |
| 1.934 |
8.594 |
13.484 |
102.464 |
| 1.917 |
8.638 |
13.348 |
102.315 |
| 1.933 |
8.728 |
13.651 |
101.82 |
| 1.962 |
8.674 |
13.563 |
102.688 |
| 2.209 |
8.989 |
13.87 |
102.787 |
That day was a fluke; I’m willing to admit that. Nevertheless, I do have time slips that don’t show me standing sideways just to stay up in the howling tailwind my car enjoyed, instead show only the times posted above.
The rest of 2004 the car stayed as is.
In 2005 I installed a set of SLP TPI runners and returned to the track in September:
| 60
foot |
1/8
mile |
1/4
mile |
MPH |
| 2.191 |
9.074 |
14.098 |
100.5 |
| 1.934 |
8.731 |
13.747 |
100.562 |
| 1.948 |
8.765 |
13.762 |
100.794 |
| 1.91 |
8.722 |
13.708 |
101.494 |
| 1.919 |
8.722 |
13.698 |
101.786 |
| 1.925 |
8.752 |
13.745 |
100.743 |
| 1.919 |
8.753 |
13.764 |
101.756 |
The
runners once again helped my car with an additional
10-15 hp as shown by the increase in MPH.
page
4...
|
 |
| This
is the stock Ypipe. |
 |
| Look
at the restrictions from where the two pipes come
together! |
 |
| This
is where the two collectors meet. This is more lika
a t-pipe the y. |
 |
| This
is the new mandrel bent y-pipe and off-road pipe
replacing the catalytic converter |
 |
| You
can see that this new pipe tucks up well underneath, creating
no ground clearance issues. |
 |
| The
MFBA had a track day in 2005. The GTA was in fine
form that day. |
 |
| The
chassis work completed on the car has allowed for
spectular launches like this one! |
 |
| These are some great photos taken by a member of MFBA. |
 |
| I
beat on a Mustang from the same era as the GTA all day long. |
 |
| You
can see the wideband O2 sensor sticking out the
tail pipe. Its a valuable tool in performance tuning.
This car can be sniffed at the rear due to the removal
of the catalytic conventer. |
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