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GTOJer
06-03-2004, 10:36 AM
I've been meaning to post this for some time. When I was racing at Pontiacs-In-The-Park, my bud (crew chief) said it sounded like I was short shifting 2nd gear. After listening to the video, I agree. So I did some research. At 4000 rpm here is the speed for each gear.
1st - 30
2nd - 42
3rd - 62
4th - 88

So I gain
30 mph - 1st
12 mph - 2nd
20 mph - 3rd
26 mph - 4th

Of course redline will be higher but the ratio will remain the same, so the time in 2nd is very short. Why? How do we overcome this? I would like to ask the next person who goes to the 1/4 to try something and PM me afterwards. How about shifting out of first early. This is not as easy as it sounds but perhaps trying a 4000 shift would increase time in 2nd allowing the HP to work. This should result in a fast trap speed. Thoughts?

Jerry




FLORIT
06-03-2004, 11:17 AM
Jerry, I'm going to the 1/8th tomorrow night. I will TRY to do what you suggest, but I tend to "grip it and rip it" despite all the time I spend talking about the theory. Anyway, sounds reasonable. I'll let you know.

nikivee
06-03-2004, 12:38 PM
I don't know about that. When I raced I redlined every shift, resulting in a 13.3.

GTOJer
06-03-2004, 12:51 PM
ok, I did a 13.5 but when I watch the video, I could hear what my crew chief was talking about. 2nd gear is very short. All I am thinking is short shifting 1st might give a quicker time so second gear is not wasted.

Blitzu
06-04-2004, 10:30 AM
I do know what you are talking about, when at WOT there really isn't much of second gear. I might try what you said next time at the track, but I dont know if it will actually help. Good idea though.

GTOJer
06-04-2004, 10:44 AM
I don't know if it will help either. But getting into 2nd quicker might work.

rasilverbird
06-04-2004, 12:39 PM
Wait till you get 4.10 gears.....2nd gets REALLY short ;) .

Bronko, didn't see you at the MIR shootout, you missed a good time.

Take every gear to redline, unless you put your car on the dyno and see power dropping off way before redline (which I don't think any of you will see). Pull 'em all to the end, and watch the ET drop :drink:

BillyGoatGruff
06-04-2004, 02:00 PM
With the 3.91 gears I try to get to second as fast as possible, but I can't stay there too long. Everyone is correct second gear is really short.

FLORIT
06-04-2004, 05:54 PM
My night at the track was rained out. Sorry, it'll be next Friday before I get a chance to try this on a dragstrip. I'm not the best guy to do the experiment, though. I'm still learning. I will also be going back to this 1/8th mile track with drag radials, a carbon fiber hood, and updated fuel trims. If I get better times, I won't know "who to thank." Besides, I'm not working on ET...

Sixty foot times, sixty foot times, sixty foot times... (My Daily Meditation)

OrangeCrushM6
06-04-2004, 06:19 PM
My night at the track was rained out. Sorry, it'll be next Friday before I get a chance to try this on a dragstrip. I'm not the best guy to do the experiment, though. I'm still learning. I will also be going back to this 1/8th mile track with drag radials, a carbon fiber hood, and updated fuel trims. If I get better times, I won't know "who to thank." Besides, I'm not working on ET...

Sixty foot times, sixty foot times, sixty foot times... (My Daily Meditation)

Take care of 60' times, everthing else takes care of itself. :)