30th t/a

iTrader: (51)

In my researching cars and performance I’ve come to find out that a NA car needs power to weight ratio of around 6.9-7.0lbs/1 rwhp to trap "around" 130mph in great weather and when it comes to FI it seems the cars need around 6.0-6.2lbs/1rwhp to trap around 130mph in great weather.
NA Examples:

Ws6transam01 – cartek 4X H/C package 480rwhp – 412rwtq – race weight is 3325 = 3325/480 = 6.9 actual timeslip was 10.5@129 with a 1.40 60’

Speedracer5532 - Rapid motorsports 402 stroker - 527rwhp/465rwtq - race weight 3700lbs = 3700/527 = 7.02 actual timeslip was 10.8@130 60’ ??

C5_CU with an H/C C5 vette made 453/403. With a race weight of 3364lbs the power to weight ratio comes to be 7.42 and his best mph was 126. Looks like if he gets his weight to power ratio to around 7.0 C5_CU will have his 130mph traps.



FI Examples:

04 Kenne Bell Cobra making 630rwhp with a raceweight of 3820lbs (estimated) = 3820/630 = 6.0 the Kenne Bell Cobra should be right around 130mph with this rwhp.

Tiagos T74 turbocharged Ls1 Trans am making 615rwhp/600rwtq went 11.5?@131 with a unknown 60’ a full weight trans am plus a turbo kit is roughly 3700lbs. 3700/615 = 6.0



Stenod with a 100% stock trans am with a Incon twin turbo kit and race gas made 583rwhp. His raceweight was 3790lbs. so 3790/583 = 6.5lbs/1rwhp and his best was 11.0@127. as you can see his weight to rwhp was not 6.0-6.1/rwhp and he didn’t trap 130mph but his weight/rwhp was close to 6.0 and his mph was only 3mph away from 130.


anyone know why its like this?

BrandonDrecksage

iTrader: (1)

there is more than just power to weight ratio. Power to weight ration has to do with peak power. if you have a dyno queen...you'll need more power cause your under the curve power is lacking...hence why you need a 1000hp supra to run the same time *** a 700hp ls1.....2jz engine is a lot peakier than a ls1. Suspenion setup and tire choice also will make mph different..fi you hook up really good..your mph might suffer a lil, but your et will improve.
also, with a turbo car..that has a large turbo that needs time to spool...so after a shift...it will need to respool to full boost.

30th t/a

iTrader: (51)

i know under the curve power is important but on a kenne bell cobra and a turbo ls1, they have huge under the curve power. the only thing i can see that would hurt a turbo car is the spool time off the start, but most turbos are spooled by 3000 and when your racing, i dont think the shift points go even close to 3000, so the turbo/s should be already spooled. correct?

BrandonDrecksage

iTrader: (1)

when you shift...the bov lets the air preassure out....so if your running 20psi...the turbo has to create that again. the turbo ls1 probably has less under the curve power...if you really want to research this...you have to get all of the data and a dyno graph of each car and the track conditions...

also..gearing has effect on mph also....to many varibles to just label it saying that a turbo needs more power to trap the same as na.

30th t/a

iTrader: (51)

cool,thanks for the help.

Hennytime

iTrader: (33)

is it just me, or did all off the heads/cam cars run 10's, and none of the FI cars did, but they had higher traps....