The required hp goes up roughly as the cube (third power) of the speed. Adding 33% to the top speed will require (1.33 x 1.33 x 1.33 = 2.35) times as much hp.

A Mercedes 560SEC that can reach 142mph with 238hp requires about 600hp to reach 200mph.

 

Like someone mentioned, Supercars Exposed on Speed did a test of a bunch of cars trying to reach 200mph at the Texas mile. They couldn't do it in a Porsche Carrera GT, they managed to do it in a Ford GT which had a big *** modified supercharger. I don't think that you'll be able to do this in the G.

 

Yep. With my calcs, it would take about 550-600whp to possibly achieve 200mph in a 1st gen G35.

 

ok well then i guess i will be aiming for the 165ish then. ive gone 158ish in it before my turbo's. but now that i think about it.. i wont know how fast im going once i hit 160 since my speedometer only goes there obviously. i wouldnt know how fast im goin after that. i will tape up some holes before tryin it again for smoother air flow but i guess ill only be attempting to reach the 160 on the speedometer and go a little over then stop. i can reach 140 in a few seconds right now.

 

by the way... does anyone know the conversion to get crank hp? i was told/dyno says 355rwhp... wats the base or to the crank hp?? how do i tell?

 

^ get smaller pullies?

 

its just a one time thing im gunna do haha dont wanna put any more money into my car! just was wondering if there were small mods i could do. got a lot of info from the thread. i will record a video of it and if i can figure it out ill post it up. wont be anything special and will be on a "closed road"

 

^lol on the "closed road"
and most GPS systems (OEM or after market) have trip info inc. max speed, even if u cant see it on ur speedo

 

You were told? SO i assume the previous owner ran it on a dyno? Do you have the dyno sheet?? I only say this because trapping 108MPH in the 1/4 mile is low. You should be up in the 115-120MPH range if you truely have 355 rwHP. Trapping 108MPH on a 3500 pound car is typical of 300-325 CRANK HP cars ( ~ 276 rwHP).

Typically it's 15-20% drivetrain loss for an automatic. Depends on the transmission though. I do not know how efficient the 5AT is.

SO using your 355 rwHP number, you are anywhere from 408HP to 426HP at the crank. Again, 400HP crank and trapping 108MPH makes me scratch my head a little.



Please don't kill yourself. It's not worth it.

 

Lol ^+1

 

my favorite post of the day

 

When I first red OP post I was thinking how the hell a person with a G thats TT dont know what it would need to reach 200mph and then not know what is .26cd and stuff. Anyway seriously dont do attempt to do 200mph or anything untill you get proper tires and stuff thats rated to go that fast and what not. At least talk to someone who did it before so you can get some advice from a experiened person.

Top gear was having trouble hitting 170mph on the Salt flats with a Zr1 so...

 

^In only one mile of salt, on which wheel struggle for traction

Our man here has a TT G35 and (I assume) miles upon miles of nicely PAVED ("closed") roads

 

What kind of suspension are you running at the moment?

If you are really serious about some aero mods for your car, you'll have to drop some green on it. For safety and stability, you need to get the air under the car moving FASTER than the air above it. A properly designed and fabricated undertray will create a bit of downforce without wings and will also lower the coefficient of drag (your cD.) But this involves a LOT of time, R&D and testing to ensure proper balance.

I wouldn't worry about getting wide wheels and tires, they will only contribute to mechanical drag and will slow your down. Deep dish wheels are basically buckets on the side of your car to scoop up air and ruin your cD. Pick up a set of flat faced wheels; if they have reverse chamfered spokes on the face, those are a winner. As for tires, stay about the same width as stock, but go for something that will have a stiff sidewall to help the car track properly. A crosswind at high speeds with a bit of flex from the tires is enough to get the car wobbly.

Suspension... get something reputable. Ohlins, KW, Bilsteins, Konis; all of those are decent. Stay away from progressive rate springs. Even the shocks that are 'matched' to a progressive rate spring will have issues with predetermined knee-over points because the spring rate is ever changing. That doesn't really make too much of a difference in ride comfort, but it makes the car not nearly as predictable as a car with straight-rate springs would be.

I think that you'll be able to break 200mph with about 480rwhp with a good undertray.

 

Notice what kind of wheels each car in this pic has...