What estimate 0-60 times and 1/4 times do you think id get with a semi fresh mild 300hp 350 carburated 700r 3.42 gears stock otherwise. Remember an estimate is all im looking for. Thanks

 

need weight.. beat that same combo... it ran 14.6... I ran 14.3 when I had my 305 T5 3.73 suppertrapp catback sleeved cat 58mm TB 30# inj and my tune

 

Uh stock 87 firebird so about 3300lbs

 

well, i took a guess on the weight (3400 with the driver and 300hp) comes to a 13.91 on one of those calculators. but depending on sea level, track conditions, tires id say low 14's. maybe break a 13's on a perfect day and perfect run.

 

Uh car with driver... Unlike the guesstimate above making the driver 100# most women weigh more.. A LT1 vette has 300 less weight and only pulls a average 14.1

 

is that 300 whp or 300 hp at the crank ?

 

i am wodnering the same thing i have 92 firebird t-tops my car dyno ats 202 hp at 4417 rpm and 268 tq at 3673 rpm to the tires out of a 305 tbi what do you think my 0 to 60 is and 1/4 mile i did a rear swap to went fro ma 2.73 to a 4th gen 3.42 posi i was running a 9.7 to 9.8 1/.8 mile with the old rear end

 

300 at the wheels

 

you need the weight. even a rough guess? then use this.
http://robrobinette.com/et.htm

 

Hey thanks thats a really good site, and i can play with hp and weight to see best combo

 

no problem.

 

The ET calculators are horrible. You are better off doing a calc for the trap speed.

300hp and about 3500lbs (race weight includes driver, so I'm estimating), would be low 13's around 100-103mph.

My car traps ~103mph with a race weight of 3750lbs, that calculates out at ~320hp flywheel.

 

We keep seeing those #'s but they don't match your mods.

Get that thing to the track and report back with your trap speed and weight and you'll either be proven right or wrong.

Your in florida, there should still be a track open.

 

Is the rear end a 3:42 posi? And what size/brand/type are your rear tires? Width in particular. Traction matters!

 

Its also one of the most complex variables in ET estimation. The complexity is pointless, too many variables to account for.

Driver Reaction
Driver Skill
Torque Multiplication through the torque converter
Tire traction
Track Temp
Gear ratios
...
it goes on and on.

Unless you have a degree in physics its not worth the effort.

 

roughly 13.9 with 300hp

13 flat with 300 rwhp

*all times based off perfect conditions and good driver*

 

Using a sim a 5500 redline 300hp at 5000rpm 360tq @ 4000 rpm and a race weight with driver of 3670 stock gearing and a 3.42 rear.

I get with redline shifts and a good launch
0-60 5.4 1/4 @ 14.2 @100.2mph

I also used aerodynamics for a 1990 TA because that is the only one I have.

 

300rwhp is better than a 13 flat with a good driver and conditions, closer to mid 12s.

I do 13.35 @ 102.8 on street tires. My car weighs 3750lbs with me and the laptop bag in it + 3/4 tank of fuel. Using the HP from Trap speed formula below thats about 320hp. HP = 3750 * (102.8 / 234)^3. Answer is 317.9HP estimated.

Here's how I know. And a few examples of stock cars.

Formula is HP = Weight * (Speed / 234)^3 This estimates flywheel HP, not Wheel HP.

Lets take a car that we know. A Chevrolet C6 Z06 weighs about 3150lbs, and traps about 125mph. But since only KITT can drive by itself we need to add in driver weight. Lets put that at 200lbs for an estimate, so 3350lbs race weight.

HP = 3350lbs * ( 125mph / 234)^3
HP = 3350lbs * .53419^3
HP = 3350lbs * .152434
HP = 510.65hp.

A Chevrolet Z06 is proposed to make 505hp. The estimation is pretty close. That formula estimates HP from trap speed. What if you want to go the other direction? There's a formula for that too. This also uses crank HP. Lets use the Z06 again for comparison between the two.

MPH = 230*(HP/Weight)^1/3

MPH = 230*(505/3350)1/3
MPH = 230*(.15075)^1/3
MPH = 230*.53221
MPH = 122.4mph

Again, we are pretty close here, its very possible to run a 122mph trap speed as there are variables we simply can't account for with such a simple formula.

So how about the OP's question then? 300hp? 3300lbs curb weight? Add in a 200lbs driver too.

MPH = 230*(300/3500)^1/3
MPH = 230*.085714^1/3
MPH = 230*.44091111
MPH = 101.4mph

There is an alternate trap speed estimator formula that was published in the 50's, its only slightly different being MPH = 224*(HP/Weight/^1/3.

 

i was just going by most ls1 f body times--- which are around 300rwhp--- and run around 13 flat. but they are a touch heavier i guess.