If trap speed gives you some idea of the hp your making, then why, after doing my T5 swap, am I trapping 1 to 2 mph slower. Before and after dyno # show I gained 30 hp at the wheels. I also switched to an electric fan. Now I'm not complaining because I knocked over a second off my best time, just wondering why trap speed didn't go up with 30 more ponys at the wheels. Maybe driver error.

 

you now shift, not the tranny, valuable time lost if shifts that may be lazy, drive it like you stole it!!! also, the time of year and wheather are all a factor when comparing one race day vs another, no two days are the same when race events are spread out over a time period, for example if I race in the spring then again in the summer = two different et's, most likely higher in the summer

 

Yeah, good points, I did notice my first couple passes I was on the rev limiter in 3rd going thru the traps, say the last 50 ft. So I started short shifting 4th and gained 2-3 mph right there. I'm definitely not easy on the shifting, but do use clutch. Maybe I have alittle more I can get out of it with shift points. Can't wait for spring.

 

You also stated you knocked a second off your ET. The faster you get down the track the lower your ET will be. In my last car it ran 11.79@118.5 on slicks. On street tires it would trap nearly 121 but the ET would be a few tenths slower.

 

Yeah, but I attributed the full second drop in time to my 60ft. Went from 2.2's to mid 1.6's. And yeah the first runs with the auto were on street tires, 5 speed had to go with slicks. What a blast that was.

 

So what were the times and mph along with whats your set up?

 

Its an 87 notch, 306 with all bolt ons, supposedly a letter cam, e7's with some work done to them, aod decent shift kit with 2800 stall, 3:55's. Bought the car as is so can't really verify much. Ran a best of 13.5@108.5, 2.22 60 ft. in good air. Dyno'd 270 rwhp and 290 trq.

After T5 swap and switch to electric fan, dyno'd 300 rwhp and 313trq. Best time was 12.45 @106.5. 60ft was 1.64. Air was not that good, 85' and humid. Car weighed in at 2700 on scale at track. An old old scale. Also this was run with a set of Weld big and littles with 26x8 slicks.

Do slicks really suck up mph, I was running about 20lbs in them.

 

Well that's kind of mind boggling if I do say so myself.

I dont personally believe slicks hurt you as bad as some will say. With my bolt on set up up I went from drag radials to slicks and running faster with slightly better mph. But the hot weather could of made the big difference if you ran in nice cool weather before but to me the whole think doesn't add up....

How was your 1/8 mile times and mph's?

 

I'd check your incremental times, the 60', the 330' and the 1000' to really see whats happenening.
I also don't think you need 20PSI in the slicks.........

 

Ok, these or from some timeslips I have at work. The times for the auto were not my best, but close.

Auto……60ft----2.297
330-----5.990
1/8-----8.939
MPH---83.62
1000----11.480
1/4-----13.62
MPH--108.55

5 speed …60ft----1.66
330----5.083
1/8-----7.947
MPH----86.97
1000----10.407
1/4-----12.495
MPH---108.29

I gave a wrong mph in a previous post, my averaged 106/107.
Comparing 1/8 mph, I'm doing something wrong. But there is only the shift to 4th left.
Maybe I'm just being a skirt, but 30 hp more and also 70lbs less rotating weight (I weighed all the wheels ) you'd think I'd trap alittle higher.