What makes a 944 Spec Car Faster (and slower)?
10-18-2010, 11:33 PM
#1
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Thread Starter
What makes a 944 Spec Car Faster (and slower)?
Below is some Traqmate data from 3 944 Spec drivers at our last race at Putnam Park - the local fast guy, a mid packer, and a new guy. The effects of later braking, and trail braking are clear to see.
A few more data points. A 180lb passenger cost the fast guy .4 seconds in lap times. Full tread RA-1's vs. 2/32nds RA-1's - costs 2 seconds!
Full-size link here:
http://sterlingdoc.smugmug.com/Other...81_u7Tzb-O.jpg
A few more data points. A 180lb passenger cost the fast guy .4 seconds in lap times. Full tread RA-1's vs. 2/32nds RA-1's - costs 2 seconds!
Full-size link here:
http://sterlingdoc.smugmug.com/Other...81_u7Tzb-O.jpg
10-19-2010, 11:03 AM
#3
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Very nice!!
10-19-2010, 01:51 PM
#4
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Thread Starter
Most interesting is correlating the braking with lateral G graphs. The slower guys brake in a straight line, and then abruptly get off of the brakes right when they turn in. If you park the timeline on the TM right on the moment they let off of the brakes, you can see they turn in right then. The faster guy releases the brakes more slowly - this can clearly be seen in the red car's graph in the first major corner.
The new guy complained that his car understeered in that corner. The hotshoe took the car out and found it to be pretty well balanced, and duplicated the cornering speeds in the slower guys car. Once the new guy realized this, he was able to fix his "handling" problem through trail braking, and went faster.
This is one of the very fun things about a spec series - comparing data, and helping everyone go faster/accellerating the learning curve. You still have to have the skill to implement what you learn, but we promote a "no secrets' attitude. Everyone shares data, and often, cars. What we've found is the fast guys are fast, no matter who's car they're driving. No allegations of cheating - no basis when the fast guy goes fast in your car! We also all shared dyno results last weekend. The 4th place guy had the most HP, by a small margin.
944 Spec is considering a rule that allows data to be collected and shared (at the end of a weekend) on any car. This is done in practice already, but we are considering making it a formal rule. Might be an ineresting thread topic...
The new guy complained that his car understeered in that corner. The hotshoe took the car out and found it to be pretty well balanced, and duplicated the cornering speeds in the slower guys car. Once the new guy realized this, he was able to fix his "handling" problem through trail braking, and went faster.
This is one of the very fun things about a spec series - comparing data, and helping everyone go faster/accellerating the learning curve. You still have to have the skill to implement what you learn, but we promote a "no secrets' attitude. Everyone shares data, and often, cars. What we've found is the fast guys are fast, no matter who's car they're driving. No allegations of cheating - no basis when the fast guy goes fast in your car! We also all shared dyno results last weekend. The 4th place guy had the most HP, by a small margin.
944 Spec is considering a rule that allows data to be collected and shared (at the end of a weekend) on any car. This is done in practice already, but we are considering making it a formal rule. Might be an ineresting thread topic...
