Mph Vs Hp

[The Dan]

You need to also take into account the 60ft. Its a good indicator of wheel spin which will up the mph.

Then also Peak HP means nothing average HP is were its at.

I have run(all diff cars) :

12.1 @ 116 mph 1.8 60ft in 1180kg car 280rwhp

11.4 @ 117 mph 1.5 60ft in 1140kg car 320rwhp

11.4 @ 119 mph 1.5 60ft in >1200kg car 400rwhp

10.89 @ 127 mph 1.49 60ft 1200kg car 420rwhp

10.35 @ 128mph 1.45 60ft 1130kg car 455 rwhp

As you can see the MPH to HP translation is not that simple. Especially when you look at the two 11.4s one car with 80rwhp more.

One was a peaky sl_ut other had power everywhere. Weight also played a big part.

Unfortunately SAU has bred a massive group of overnight experts. These experts contest nearly every dyno graph posted and comment on their (limited) experience with the subject.

The truth is, there are so many different factors that will effect your overall time or MPH and there is not a perfect relationship between MPH and HP. Only similarities.

[Guilt-Toy]

Unfortunately SAU has bred a massive group of overnight experts. These experts contest nearly every dyno graph posted and comment on their (limited) experience with the subject.

The truth is, there are so many different factors that will effect your overall time or MPH and there is not a perfect relationship between MPH and HP. Only similarities.

Thanks for your (limited) opinion.

[Cjmartz2k]

Unfortunately SAU has bred a massive group of overnight experts. These experts contest nearly every dyno graph posted and comment on their (limited) experience with the subject.

The truth is, there are so many different factors that will effect your overall time or MPH and there is not a perfect relationship between MPH and HP. Only similarities.

I'm not sure who that was aimed at

I think most of the posters in this thread understand the fact that weight has just as much an effect as power for a given mph. That's why I mentioned asking for the weight in the original post as well as several subsequent posts. I was more looking for results people have gotten and less of a debate. I wholeheartedly agree that there are way to many factors even besides weight that come into play to call people dyno figures BS

Somebody said it best earlier in the thread. MPH vs. E.T./weight/60' can give a good indication of how much faster the car could go with it's current setup. MPH vs. weight is only a broad indicator of what kind of power somebody is making. Unless somebody is claiming 600rwhp with 110mph trap speeds, I really don't see how you can call BS. Dyno read outs are ONLY good for two things IMHO. Comparing to other cars that have run ON THE SAME DYNO, and seeing what kind of gains or losses you make when adding parts or tuning (again, from the same dyno).

For all the nay sayers about traction effecting mph (2rismo comes to mind), Okinawa has EXTREMELY slippery roads. I get my times from a Gtec as mentioned. My best run is an 11.8 @ 124mph, and my best mph is 128 mph on drag radials with a 2.0 60'. I put street tires on and I cut 2.3 60's and 12.4-12.8 at 117 to 120 mph. That's almost a 10mph difference just changing tires.

All that being said, it might be easier/a bit more accurate to say "your R32 GTSt has XXX rwhp because you ran XXX mph" if you are talking about 2-300rwhp cars running 14's and 13's. You start getting down into the 12's, 11's, 10's, etc, and I think it's real tough to make a "BS!" call on somebody's dyno sheet.

Edited May 5, 2009 by Cjmartz2k

[Swiper the Fox]

Unfortunately SAU has bred a massive group of overnight experts. These experts contest nearly every dyno graph posted and comment on their (limited) experience with the subject.

The truth is, there are so many different factors that will effect your overall time or MPH and there is not a perfect relationship between MPH and HP. Only similarities.

Bad post Dan...my dyno figures have always correlated with my MPH considering the weight.

There are those that say and those that do....but there is also people who say...and do!

[FineLine]

Bad post Dan...my dyno figures have always correlated with my MPH considering the weight.

There are those that say and those that do....but there is also people who say...and do!

Waddabout them Knights aye paul.

[Swiper the Fox]

Waddabout them Knights aye paul.

The south pacific knights...lol

[FineLine]

The south pacific knights...lol

I did chortle.

[R31Nismoid]

Bad post Dan...my dyno figures have always correlated with my MPH considering the weight.

There are those that say and those that do....but there is also people who say...and do!

Same for me when i was racing every weekend for 6 months

[Guilt-Toy]

Same for me when i was racing every weekend for 6 months

Not so limited opinion then

[unique1]

out of most of the people i have seen at the drags there mph always comes very very close to the hp they are making when put into the drag calc using the cars proper weight, these cars are ranging from 200 - 600rwhp setups. I find the only ones to run seriously quick times for low mph are the transbraked auto setups but 99% of imports are manual anyway so not really worth a mention in here

Edited May 5, 2009 by unique1

[The Dan]

Thanks for your (limited) opinion.

Wasn't talking to you so don't start on me.

I'm not sure who that was aimed at

I think most of the posters in this thread understand the fact that weight has just as much an effect as power for a given mph. That's why I mentioned asking for the weight in the original post as well as several subsequent posts. I was more looking for results people have gotten and less of a debate. I wholeheartedly agree that there are way to many factors even besides weight that come into play to call people dyno figures BS

Somebody said it best earlier in the thread. MPH vs. E.T./weight/60' can give a good indication of how much faster the car could go with it's current setup. MPH vs. weight is only a broad indicator of what kind of power somebody is making. Unless somebody is claiming 600rwhp with 110mph trap speeds, I really don't see how you can call BS. Dyno read outs are ONLY good for two things IMHO. Comparing to other cars that have run ON THE SAME DYNO, and seeing what kind of gains or losses you make when adding parts or tuning (again, from the same dyno).

For all the nay sayers about traction effecting mph (2rismo comes to mind), Okinawa has EXTREMELY slippery roads. I get my times from a Gtec as mentioned. My best run is an 11.8 @ 124mph, and my best mph is 128 mph on drag radials with a 2.0 60'. I put street tires on and I cut 2.3 60's and 12.4-12.8 at 117 to 120 mph. That's almost a 10mph difference just changing tires.

All that being said, it might be easier/a bit more accurate to say "your R32 GTSt has XXX rwhp because you ran XXX mph" if you are talking about 2-300rwhp cars running 14's and 13's. You start getting down into the 12's, 11's, 10's, etc, and I think it's real tough to make a "BS!" call on somebody's dyno sheet.

Wasn't aimed at anyone. Just a general observation. It can be denied by anyone, I don't really care but it's a fact. There are too many people who don't know shit from breakfast and post their comments regarding someone elses dyno graph calling BS on the figure given because they think they know.

And it's not just with dyno graphs, it's with most of the common topics around FI.

Bad post Dan...my dyno figures have always correlated with my MPH considering the weight.

There are those that say and those that do....but there is also people who say...and do!

Yeah mate, I know why you would say that but you may be misunderstanding the point I am trying to make. That is: For people like you, who are constantly on the track , racing and improving their times, HP vs MPH is a good indication of a power increase and vice versa. But for joe blow who has his first time at the track, a slower MPH doesn't always disprove the HP he posts up with his dyno graph. I was trying to make the point that all the different aspects of the track and the car come into play and it's not just a simple MPH / HP direct ratio.

Like I said earlier, they share similarities, but there are many other factors involved in the equation and even for someone like you, if you change one of those factors, your MPH will change.

Put some Falken 452's on the back of your car, take it out again and see what MPH you run, I'm sure you will run at least 10mph less than your best and your 60foot will represent this. It doesn't mean you have lost HP

[Butters]

3lit3 32 - I think has a point as its the same one I was trying to make. (leaving out the experts comment - I stay switzerland on that one)

my dyno figures have always correlated with my MPH considering the weight.

Dirt garage if you change the dynamic of your engine's power. You can make less hp(peak) and run more MPH.

I have done this with my car on more then one occasion. I am sure you already know this though.

I am not disputing that HP(peak) can be indicated from mph, knowing weight and 60ft.

Its just as 3lit3 32 said its not a perfect relationship.

[R31Nismoid]

I think the similarities are much better than some dyno sheet which can be as wayward as it gets in many cases.

I refer to R33GTRKid again, his dyno with "X" power should have roughly equated to "Y" MPH. Car was run, car was LOW on MPH by 4-5MPH and i said that the MPH vs HP wasnt correct (from memory)

So upon investigation - turns out a boost leak had appeared from the time he left the dyno, to the time he ran the car.

So MPH was in that instance a very good give away there was a problem/car didnt have the power that was claimed. He fixed, and instantly noticed the car felt better.

Happy campers all around, problem sorted, 10/10 happy he was.

Of course there is more too it (he provided 60ft times and all that info), for the opinion to come about. But the essence is still there that its relative.

So whilst there are variables, its still reliable if you've got a relative idea of where it should be at.

Not so limited opinion then

hehe. Apprently not

I haven't raced for a few years, but i was out there for long enough to get an accurate idea

i knocked about .7 of a sec off over that time as i learnt to drive my bucket ... funny thing though the MPH was virtually unchanged (as the power wasnt)

[Guilt-Toy]

hehe. Apprently not

I haven't raced for a few years, but i was out there for long enough to get an accurate idea

i knocked about .7 of a sec off over that time as i learnt to drive my bucket ... funny thing though the MPH was virtually unchanged (as the power wasnt)

hehe. .7 is not a bad effort! if i could get a .7 improvement from my first outing of 11.3 i would be one happy man

Might be going back on saturday for another go. this time with a BOV and flat shift and hopefully different rubber

[R31Nismoid]

I'll be the first to admit i had NO idea how to drive back then

[MBS206]

300rwhp cars show up my car? hmmmm.. tell me where there is a 300rwhp r33 that does 11.11sec at 128 - 131mph ? and has a power curve like this. (torque drops from over 1000nm to 800ish nm by red line by most)

Anthony, take notes of the words DYNO QUEEN.

Your car is actually built to go. I'm talking about the cars that go "nothing nothing nothing" and in the last 500RPM smash out a ridiculously high number.

You hvae ALOT of area under the curve. Which equates to actually GOING SOMEWHERE. IE, Not a dyno queen...

[Guilt-Toy]

Anthony, take notes of the words DYNO QUEEN.

Your car is actually built to go. I'm talking about the cars that go "nothing nothing nothing" and in the last 500RPM smash out a ridiculously high number.

You hvae ALOT of area under the curve. Which equates to actually GOING SOMEWHERE. IE, Not a dyno queen...

Hahhha i like! Cheque's in the mail

[RRob]

R32 GTS 1480kg with driver. 129.7mph and 470-490 rwhp.

[MBS206]

Hahhha i like! Cheque's in the mail

I'm actually envious of your car...

Mine goes on the rollers next week (If everything goes to plan...) it reaches the mechanics tomorrow... (FINALLY!!!)

If I can get even HALF of the area under the curve that you have, I'll be ecstatic!

I need a better turbo on their... (Although, can't complain for a 6boost mani + turbo for $1000... )