G8 Track Test
I wanted to drop you a line to let you know that your numbers don't jive in the G8 article ("First Test: 2008 G8 GT," August 2008 GMHTP). The dragstrip numbers would lead the casual reader to believe that you picked up 5-plus mph in the quarter-mile with a tune. Based on the car weight, this would indicate an improvement of approximately 50 rwhp.
This isn't possible based on the 13 horses and 11 lb-ft of torque you picked up on the dyno. With those numbers in mind you would expect to see approximately a 1.5-mph gain, not the 5-plus-mph gain you posted. Stock G8 GTs will run 103- to 104-mph trap speeds, so it would appear that your baseline was not accurate. Neal Stewardvia e-mail
Thanks for your inquiry Neal: though the baseline wasn't exactly inaccurate, it wasn't optimized, either.
As stated in the article, Tune Time Performance's dyno was reading low during our baseline and modded runs, due to different calibrations (and a recalibrated, post-story dyno session on it showed another 10 horses at the wheels, at around 285, with no other changes).
However, the benefits of our performance tune included removing torque management, and upping the rev limiter. That last one was what made a huge difference during after drag testing, as during the G8's baseline runs, it was actually shifting into Fourth, killing the mph. Once the tune was in, it was able to take advantage of the high rpm in Third to record a much higher trap speed.
Taking Paint & Body Further...
I'd like to comment on the feedback you received regarding your bodywork issue. I say, "Good article." However, I think you could have even gone a step or two further.
As you mentioned, even the fourth-gen cars are now 15 years old. In my opinion, the flexible bumpers are really showing the ill effects of age. My 1996 Z28's bumpers could stand a refinish, however, I don't know how to approach it.
I don't want to do a quick "Scuff, Sand, and Shoot," as many people advocate, and I've heard chemical strippers can wreak havoc with the urethane material. I've looked into "soda blasting" with no real conclusive information.
I know that your Formula repaint article was pretty comprehensive. As a subscriber, I read the article a long time ago and don't remember all of the details. If, by some chance, you showed how to correctly strip and refinish the soft bumpers, I apologize. If you didn't, I think it would make for a good technical article.
Thanks, and keep up the interesting articles!Lon BoyerWebster, Ny
I enjoyed the Paint & Body articles: I found them to be useful references for the bodywork I'm performing on my 1995 Firebird V-6-to-LS race car project.
I'm concerned that no complaints regarding the lovely model were printed. Did the paint and body letters actually outnumber the model complaint letters?Scott RobinsonTipton, In
Actually, they were about even!
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