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Discussion Starter · #1 ·
I am little confused on some of the times posted by board members, and the rwhp dynojet numbers they make.

Case no.1
Klodner coupe makes 1,006rwhp yet only runs 151mph in a 3200 or so car. Andrew makes over 700rwhp I think and runs 145 at about the same weight.

Seems the Sam car(z28) runs high 9'[email protected] and yet only makes about 580rwhp and is a heavier car? something must be happening on the correction factor on the dynojet. Something to do with intake manifold pressure vs. atmospheric readings?

Any explanations? seems when a n/a car can come within 100rwhp or so of a power adder car they seem to run about the same times.

Input ??

Mike89lx,01 Cobra
 

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rule of thumb.. from what I have noticed... which is not always true.. but most of the time it seems to be... you get mph from HP... you get ET's from torque.... the car putting out 1000 hp.. may only be getting about 700lbsft of torque... the 700 hp car you refered too.. may be making 1000 lbsft of torque... hence same ET as the 1000hp car yet slower speed...

Don't know if this is totally correct.. but it is a rule of thumb I have always went by.

I would be interested in hearing other peoples opinions on this as well!
 

· Married Man on 14Feb2010
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[CS]ls1haha said:
I think that there are two other critical elements of drag racing that you have failed to recognize. The engine, although greatly responsible for the car's performance is only as good as the drivetrain and suspension.
Don't forget driver skill. Some people can just drive. I for one am not one. Maybe with tons of practice but I still doubt that I could drive a 700+rwhp car and make it go 9s.
 

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Discussion Starter · #5 ·
I dunno many many 96-01 Cobras with blowers making 400-450rwhp seem to run around [email protected] yet ls1 fbodys run 118-124 with only 400-430rwhp? at the same weight. I have been told that the dynojet numbers for a power adder car are not as accurate as a n/a car.

Mike89lx,01 Cobra
 

· Still Slow
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a cobras power with a vortech for say it far from flat, it takes time to get into the powerband, a cobra with 4.56 gears and a blower should really tear ass, a ls1 has a much flatter powerband so the hp number avg's out more during the race because it doesnt cut in half when they shift....
 

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its not all about hp it is all about how you use what you have. look at some of the stockers. take the ls1's they are running low 10's. then you have the sams car that has a 422 with 4 speed solid roller blah blah blah. why is the stocker so close? they use evrything they have.


go to evan j smith he runs 11.teens with a 306 cobra intake iron gt-40 heads stock lift cam blah blah blah. i doubt to many people on here with there n/a cars can out run him. it is all in how much of the power you make gets used.
 

· Merry HoHo
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mike89lx said:
I am little confused on some of the times posted by board members, and the rwhp dynojet numbers they make.

Case no.1
Klodner coupe makes 1,006rwhp yet only runs 151mph in a 3200 or so car. Andrew makes over 700rwhp I think and runs 145 at about the same weight.

klodner's car,was he on slicks? if not then i am sure he had to walk it out of the hole some. Andrew was on slicks and cut 1.5> sixty foot times, and run low six's in the 1/8 while chad only barely dips into the six'.
the sam car is an auto and does not loose as much time with shifts as both chad and Andrew. now put autos in thier cars and you will be looking at some low nine high eight second cars.

on a side note, the turbo cars torque curve changes under differant loads, if ever put slicks on that car, it would but freakin scarey.
 

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Re: Re: Dyno numbers and track times???

SNEAKY said:
klodner's car,was he on slicks? if not then i am sure he had to walk it out of the hole some. Andrew was on slicks and cut 1.5> sixty foot times, and run low six's in the 1/8 while chad only barely dips into the six'.
the sam car is an auto and does not loose as much time with shifts as both chad and Andrew. now put autos in thier cars and you will be looking at some low nine high eight second cars.

on a side note, the turbo cars torque curve changes under differant loads, if ever put slicks on that car, it would but freakin scarey.
the SAM car has a jerico 4 speed in it.
 

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Discussion Starter · #11 ·
Yes the SAM Z28 has a 4 speed and makes over 150rwhp less and weighs more than Andrew car? yet runs 140-141 all day long. Something must be going on in the correction factor with the dyno. I think engine dynoes measure intake pressure where as rear wheel dynojet numbers measure atmosphere pressure as a correction?

The numbers just don't add up?
For example I plug in 3610lbs and 104mph it pops up 312 hp(at the crank), my Cobra makes 280rwhp and weighs 3610 w me in it(1/8 tank) so it is real close. Klodner's numbers just don't add up nor Andrew's?

Please explain ne1?

Mike89lx,01 Cobra
 

· The Janitor
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What i have picked up from Bryan Sharer is that 60`fts make all the difference here. If you can cut a DAMN good 60 foot, and put the power to the ground sooner, you EFFECTIVELY increase the length of track. Instead of hooking later on as you shift into 2nd and have 1150ft to accelerate to your maximum speed, if a car can begin its acceleration at 30 feet , BAM, you effectively just added track length that you can use to gain that much more MPH than the guy with 300 more HP can do .

Does this make sense to you Mike? :confused:
 

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Discussion Starter · #14 ·
Yes it does 32v but Andrew cut's better 60 ft times than the SAM z28 yet only runs 5 mph faster with a lighter car and 200rwhp more:confused:

I know about area under the curve, maybe a n/a car can make much less rwhp and pull nearly the same numbers as a blown/turbo car? There is something going though I beleive with the correction factors on engine dyno's vs. rwhp dynojet correction factors.

Mike89lx,01 Cobra
 
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