View Poll Results: What is the trap speed?
119-121mph
16
47.06%
122-124mph
18
52.94%
125-127 mph
0
0%
128+
0
0%
Voters: 34. You may not vote on this poll
3750lbs, 450RWHP, 1.52 60ft, 500ft DA trap speed is?
03-20-2008, 02:34 PM
#21
How about this example....
450rwhp ,3680lbs., th400, 12 bolt, 3.73 , 28" tire ..... went 10.3 @ 130mph
438rwhp, 3400lbs., M6, 12 bolt , 4.56 , 28" tire ...... goes 11.3 @ 122mph
Same Dyno!
This isnt a guess I saw both cars on the dyno and both cars run those numbers at the track.
So it does matter!
450rwhp ,3680lbs., th400, 12 bolt, 3.73 , 28" tire ..... went 10.3 @ 130mph
438rwhp, 3400lbs., M6, 12 bolt , 4.56 , 28" tire ...... goes 11.3 @ 122mph
Same Dyno!
This isnt a guess I saw both cars on the dyno and both cars run those numbers at the track.
So it does matter!
So where were these passes made, same day same track both cars?
The bottom car looks correct, the top car looks like it is lighter than 3680lbs ALOT lighter...unless it was weighed on 4 corner scales I call BS on that one.
David
03-20-2008, 02:40 PM
#22
Trap speeds can vary widely due to gearing, tire size, type of transmission, shift points, appropriateness of torque converter selection.
If you were 3200 raceweight, 5500 ATI converter, 4.56's and 28's you'd run 10.5's on motor no problem. You'd trap 127 no problem.
It all depends.
If you were 3200 raceweight, 5500 ATI converter, 4.56's and 28's you'd run 10.5's on motor no problem. You'd trap 127 no problem.
It all depends.
David
03-20-2008, 02:43 PM
#23
How do you explain the 8mph difference?
They were dynoed on the same dyno, ran at the same track (not on the same day) one was a 85* day the other a 75* day that doesnt equal 8mph.
Big deal you changed gears and didnt loose mph. Change from an auto to a Manual and you will.
Deos it matter that one car made 460 lbs of torque and the slower one made 400 ft lbs.?
I think so but that isnt your argument.
They were dynoed on the same dyno, ran at the same track (not on the same day) one was a 85* day the other a 75* day that doesnt equal 8mph.
Big deal you changed gears and didnt loose mph. Change from an auto to a Manual and you will.
Deos it matter that one car made 460 lbs of torque and the slower one made 400 ft lbs.?
I think so but that isnt your argument.
03-20-2008, 02:47 PM
#24
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I think it matters how fast it gets to 450 rwhp as well(rpm) and how long till it falls off
looking at my dynosheet my car stalls at 5400 and by 5700 I am at 410rwhp already and the dyno only goes to 7300 and it doesnt start to fall off yet(sits at 450 rwhp from 6500 onward)
so basically when I race my car is never below 400 rwhp at any time
looking at my dynosheet my car stalls at 5400 and by 5700 I am at 410rwhp already and the dyno only goes to 7300 and it doesnt start to fall off yet(sits at 450 rwhp from 6500 onward)
so basically when I race my car is never below 400 rwhp at any time
03-20-2008, 03:36 PM
#29
How do you explain the 8mph difference?
They were dynoed on the same dyno, ran at the same track (not on the same day) one was a 85* day the other a 75* day that doesnt equal 8mph.
Big deal you changed gears and didnt loose mph. Change from an auto to a Manual and you will.
Deos it matter that one car made 460 lbs of torque and the slower one made 400 ft lbs.?
I think so but that isnt your argument.
They were dynoed on the same dyno, ran at the same track (not on the same day) one was a 85* day the other a 75* day that doesnt equal 8mph.
Big deal you changed gears and didnt loose mph. Change from an auto to a Manual and you will.
Deos it matter that one car made 460 lbs of torque and the slower one made 400 ft lbs.?
I think so but that isnt your argument.
The change from a manual to an auto will most definately affect trap speed, it will loose rwhp. We all know that.
Something is askew on the auto 3680lb car, it either makes more power than stated or weighs considerably less than stated. 450rwhp in a 3700 lb car dont run 130 mph....sorry.
David
03-20-2008, 04:14 PM
#30
03-20-2008, 04:19 PM
#31
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yes it is a factor in peak RWHP, but is average hp and tq a factor i peak rwhp numbers...no it is not. is a converter the same efficiancy thru the entire rpm range and thru the shifts. NO. it is a big factor and a big differance from dyno to going downt the track. not all convertors are created equal. if you have a good clutch, then all manuals with the same gearing are.
03-20-2008, 04:28 PM
#33
yes it is a factor in peak RWHP, but is average hp and tq a factor i peak rwhp numbers...no it is not. is a converter the same efficiancy thru the entire rpm range and thru the shifts. NO. it is a big factor and a big differance from dyno to going downt the track. not all convertors are created equal. if you have a good clutch, then all manuals with the same gearing are.
Power to weight=trap speed
I give up.
Anyone seen a Moroso speed/hp/et calculator....check it out.
David
03-20-2008, 05:28 PM
#34
I think at least what I'm trying to say is that I have zero faith in dyno numbers as more often than not, they just don't jive with the trap speeds produced...There are so many folks dynoing on what I would consider "happy" dynos and don't trap for crap...I ran a corvette last year with a 466rwhp dyno graph and he only trapped 116 mph at 3500 lbs! And as others have eluded to its also about how fast the motor gets to its peak (how quick it revs), how much area is under the curve, torque numbers, etc...I have tons of area under both hp and tq curves run on a calibrated Mustang dyno and my track results speak for themselves...Its just very hard to predict mph based on dyno numbers, unless you use the same dyno and keep it calibrated...The one Wayne uses is such a dyno and Im sure they keep records of what their dyno numbers equate to at the track...
--Alan
--Alan
03-20-2008, 05:34 PM
#35
I think at least what I'm trying to say is that I have zero faith in dyno numbers as more often than not, they just don't jive with the trap speeds produced...There are so many folks dynoing on what I would consider "happy" dynos and don't trap for crap...I ran a corvette last year with a 466rwhp dyno graph and he only trapped 116 mph at 3500 lbs! And as others have eluded to its also about how fast the motor gets to its peak (how quick it revs), how much area is under the curve, torque numbers, etc...I have tons of area under both hp and tq curves run on a calibrated Mustang dyno and my track results speak for themselves...Its just very hard to predict mph based on dyno numbers, unless you use the same dyno and keep it calibrated...The one Wayne uses is such a dyno and Im sure they keep records of what their dyno numbers equate to at the track...
--Alan
--Alan
David
03-20-2008, 07:21 PM
#38
03-20-2008, 07:38 PM
#39
You got a post on how you got the car that light? I dont want to guyt my car, I love it the way it is.....but damn with my power I could do so much more with less weight. I want to keep my heater and my nice seats.
David
03-20-2008, 08:05 PM
#40
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I want to loosen my converter, but with me about to spray I dont see the need.
You got a post on how you got the car that light? I dont want to guyt my car, I love it the way it is.....but damn with my power I could do so much more with less weight. I want to keep my heater and my nice seats.
David
You got a post on how you got the car that light? I dont want to guyt my car, I love it the way it is.....but damn with my power I could do so much more with less weight. I want to keep my heater and my nice seats.
David
but dayum you need to lose weight
on the car
most of the weight I took out are stuff you wouldnt want to such as heater box all the vents and crap in the dash,airbags,bumper supports,catback,sunvisors,A/C stuff,underlay on carpet,seats(just one race seat)stock belts,sub for stereo,cruise control,light weight wheels,drag brakes,power steering,horn,abs,all the smog crap,if I have time I will cut the crash bars out of the doors,I tried to lose weight myself but its so much easier to just take it off the car,prolly many other things I cant think of
Last edited by Dave J; 03-20-2008 at 08:17 PM.