Re: Test and Tune

[Riley McDowall <mcm@intergate.bc.ca>]

At 08:15 PM 9/14/98 EDT, Shawn C Meze wrote:
>>I generally shifted right at redline, maybe I shouldn't have?
>
>theres a little trick to shifting slightly lower on the RPM band as you
>get higher into the gears. I think the 16V basically likes the
>
>1st) 6680 rpms
>2nd) 6620 rpms
>3rd) 6430 rpms
>4th) 6360 rpms
>
>as shift points that I put in as your estimated HP and TQ figures on my
>car program to get a 1/4 mile time of 16.00. This is not a definate
>number to go by, but its a good basepoint. Try these next time, see what
>happens.

When I ran my car in Seattle in July, I used these shiftpoints as a
baseline.  I was getting times in the 15.9 - 16.0 range.  Fairly
consistent.  For my last 2 runs I decided to see what happened if I wound
it right up to redline before shifing in first, second, and third.  I ran a
15.801, and that was the third of 3 back-to-back runs (meaning the car was
hot).  Granted I have a few mods that enhance top-end breathing, but it's
funny how much different 2 or 300 revs makes.

I guess the moral is YMMV.  Start with those shiftpoints and then play
around a bit...

>if your running street tires, drop the tire pressure to about 10-20psi.
>This should help you launch off the line with no wheel spin.

Speaking of launches I found the best way to hook up was to dump the clutch
at 3000 or slightly higher and then give it as much gas as traction will
allow.  I think the idea is to be on the limit of lighting the tires up.
Timing is a little tougher.  Usually us amateur import drivers will get the
easier tree, so when you're staging make sure you watch those lights!  Get
the timing down before you get to the line.  When it's your turn, try to
time it so that the car starts moving when the light goes green.  This
means you have to initiate the launch before the green goes... when I do it
this way I get RTs in the .31 or .32 area.  If you really try to jump the
light, and you don't have a lot of experience, more than likely you'll
red-light and be disqualified.  It's just not worth it.  Remember - RT
doesn't count as part of your ET. 

HTH!

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