So recently I went to the track and ran a personal best but my mph trap was lower than last season. I know that's not uncommon but what was odd was that this season's runs had a higher 1/8mph trap yet still netted a lower 1/4 mph trap then last season's best.



Slip comparison illustrates this better


Last season: no humidity, low 50s, bad headwind--------This season: high humidty, low 60s, no headwind

60ft 1.82.............................................. ...................................1.57
330 5.06.............................................. ....................................4.66
1/8 7.69.............................................. ....................................7.28
MPH 92.62............................................. ................................93.98 +1.36 MPH
1000 9.93.............................................. .....................................9.52
1/4 11.84............................................. ....................................11.42
MPH 118.78............................................ ...............................117.26 -1.52 MPH

Changes made from last season:
100 lbs lighter, qtps replace all-season 18s, BCS added to mbc (to fight taper), map 02 eliminator dump replaces muse o2 dump and 2.5-3 DP. Added cooling duct. Car is street tuned and was touched up on the track.

So why is the car's 1/8 mph higher but the 1/4mph is lower than last season?

(Edit: this season: basically all of my runs had higher 1/8MPH yet lower 1/4MPH than last season's run)

Any help would greatly be appreciated.

 

60 plus views and no comments or suggestions?! :/

 

More tractiion would reduced your top MPH so thats why your trapping lower, and have a higher 1/8 mph your hooking up alot better 1-2gear.

 

Yelp its your 60ft

 

Slicks always pull down mph but help launch. I have seen 3-4mph lost in some cars from street tires to slicks.

 

Maybe a boost leak?

 

Thank you guys for the input.

Yes, still need to do a boost leak to be safe

 

I was trapping 130-131mph and couple months later I was trapping 126-128. Did a boost leak test and found my vacuum hose to the FPR leaking. Fixed it and went back to the track. Now Im back in the 130s

 

could be a boost leak but your 60ft is def a cause. better 60 lower mph

 

WERD

Soft rubber sidewalls wick away power. 1/8 mile is up because the added grip allows you to use power you weren't previously using. The fact you only lost 1.5 mph on top probably means you probably picked up 10-20 HP since last year as well.

 

Thank you everyone for the input. I thought i was losing power. Good to know I'm not. Now i need to find about +/- 6 mph to reach my goal of 10s on stock turbo/block full interior haha

 

Yep better 60ft = better 1/8th mph and better 1/4 et and lower 1/4mph. On most platforms that's how it works.