How do you estimate HP output based on boost? Any ideas what you may be running at now? I noticed an earlier post that suggested like 225 is that correct??

 

great question....and its rediculously simple. its based on atmospheric pressure. there is natually 14.7 psi of pressure on everything on the planet at all times, including the combustion chamber of your motor. so its directly related to the hp of your motor in stock form. so if you add any boost just add it to the 14.7 already in the system. so if you have a 8psi turbo system the new number you will use for the equation will be 22.7 ....so if your motor has 140 hp stock


(14.7/ 140) = (22.7/ X)


so 140 * 22.7 = 3178

3178/14.7 = 216.19 hp

now this is an estimate, true hp can only be told on the dyno, but even then almost every dyno will show a little different number. and if you retard the timing with the MSD it will lower hp, but increase gas mileage

 

Thanks for the response that's exactly what I wanted to know.... Now, that being said. Do you by chance (or anyone for that matter) know approximate weight/HP ratios and 1/4 mile times or 0-60 times? Basically how much HP would I need to drop to say a 12 second 1/4 mile for my car's weight... I know there are a TON of other factors in this but are there any estimates or general rules?

 

you know i cant remember, it is in one of my hod rod magazines though. if i happen to be taking a ****, and see it again, i will definately post it though.

 

ok youre going to need over 500 whp to hit the 12's most likely 600whp. Theres a 2 door accord with 689 whp and it only got 10.86@136.3mph in the 1/4. So yeah, a lot of engine work and a big turbo.


lightshow, is that equation in consideration of crank or wheel?
Either way i cant run the setup i want on my stock trany lol and this is less then 2000 dollars for the setup....

 

ha mbo i just put your numbers into the calculator that was posted elsewhere. with 220 hp and i looked up the weight on a 94-97 accord it said 2855, and your tires are 19.61 inches tall and the 1/4 came out to 13.06 at 99 mph. so if that weight is right and the calculator is right then thats about what you would run

 

I think 13 is a bit overestimated you really shouldnt go based on actual calcuators because im pretty sure thats ideal in the end. Thats the downside to calculations they never consider reality in most of them ^_^

 

well with that other formula, it depicts crank hp. and if that 1/4 mile formula is correct, there is plenty of fact. when you go to drag in limited classes they use a simple formula to figure out how much hp you have. they weigh your car before you hit the strip and if you blow the doors off something, they know you have too much hp and you get disqualified. there is plenty of accurate fact in power weight ratios. and i seriously would almost bet money that mbo would run a 13 - 13.5 with a lsd and a set of nitto 555r's

 

I can't wait till I turn it up to 10 psi! a 13.5 1/4 mile would rock. Any ideas on what a 10 psi 1/4 mile would calculate out to?

I'm heading down to the local drag strip for some fun real soon.

 

i think it was sir nasty that posted the formula. ill find it and plug the numbers in though