Weight to Power in H2 class

[tanjulio]

Hello. I'm just asking about weight and power for vehicles for H2 class.

I noticed that in 2015 rules, there is a limit to max hp and minimum weight.

2015 Rulebook states "Minimum vehicle weights (listed in pounds) are the result of research based on the weights of Honda Challenge

legal racecars."

 

My questions is as follows:

How are these limits determined?...

Are both the weight and power limit based on race results or some distorted formula of available participants in H2?

 

I ask because I found there isn't a same weight to power ratio for all the engines in this class. I'd assume weight to power would be very close but it isn't .

for e.g.

ZC engine has max 140hp but minimum 2000 lbs. which is 14.3 pounds per hp. (second worse of all H2)

vs.

B18c5 engine max 190hp but minimum 2,500 lbs. which gives it 13.2 pounds per hp. (best of all H2)

 

The Type R engine has best weight to power ratio for almost all engines allowed in the H2 class; which makes it this powerful setup even more potent.

I wish I would have noticed this before I bought my ZC setup; this engine gets weight penalty relative to all B & H series monsters...

 

Thanks.

[Calif_Kid]

Hopefully you'll get an official reply on this. When I take a quick look at sections 5.1 and 5.2 of the rules, I get the following for a few of the engines, HP, weight, and weight/HP ratio:

 

Engine HP Weight Wt/HP ratio

B18C5 190 2500 13.16

B18C1 175 2400 13.71

B20B 160 2300 14.38

H23 160 2475 15.47

K20A3 155 2385 15.38

 

I'm assuming that they are taking torque into consideration as the B20B and H23 have the same hp, but the H23 has to run at a considerably higher weight. Also, the K20A3 has slightly less hp than the B20B, but the K20A3 runs at a higher weight than the B20B. I'm not sure if they just look at the hp and torque, or adjust the weight based on the actual performance. Hopefully, you'll get a reply with exactly how they set the hp and weight limits. Also, I'm not sure if you have access to it, but there have been some discussions about the hp and weight settings in the Private Honda Challenge Drivers Forum viewforum.php?f=79 at the top area of this forum - if you're not a member, then you can request to be added. - Jim

Edited November 30, 2015 by Guest

[tanjulio]

The B18C5 engine & transmission is designed for racing from Honda...so why Honda Challenge hands these drivers a weight to power advantage is beyond me.. .

I doubt they are taking torque into account, if they did they'd have the D15/D16/ZC with lowest weight to power ratio....

but...

I don't expect any suggested changes...

if I could I'd ask for lower minimum weight for my DOHC ZC setup.

 

I suspect that most of the top vehicles have the better weight to power setup...but I don't have access to any data.

SAM

[AZELISE]

Torque/area under the curve is most likely a factor. With H2 there is a set of allowed modifications. So the rule makers know the potential power curve available with the allowed mods and take that into account.

 

In the ST series in NASA the lighter the car is the worse the ratio is. Seems to follow similar trend with H2.

 

Keep in mind there is a tire width limit in H2. The lighter cars have an advantage there too. When you drive a 2500 pound car vs. a 2000 pound car on the exact same tire, power seems to be the best method to equalize that.

[mcmmotorsports]

B18c5 engine max 190hp but minimum 2,500 lbs. which gives it 13.2 pounds per hp. (best of all H2)

 

The Type R engine has best weight to power ratio for almost all engines allowed in the H2 class; which makes it this powerful setup even more potent.

 

You may wanna double check your numbers to see which has the best hp/weight in all H2

The caps were designed to equalize the playing field. A LOT of research was put into play and it isn't all about HP. Jeremy Croiset will agree to that, as will Spencer Anderson. Both run a B16A at sub 2,300lbs and consistently run up front and win races AND championships, both regionally AND nationally.

There is so much more to running up front in H2 than you think. Here in the NorthEast region, it would make your head spin if you knew how much prep and setup we go through.

[Lo-bucK]

......sigh.....

i don't know where to start.

the s2000, followed by the ctr have the best power to weight. but there is alot more to it than that. A LOT.

 

-spenc

[ILIKETODRIVE]

B18A/B = 2250lbs & 150whp = 15:1

 

Being honest: Sounds terrible, right?

 

But what if I told you that setup at 2350lb and 139whp (16.9:1) kept up regionally and could do a 14-flat in the 1/4 mile?

Oh yeah, and stock brakes. And stock aero.

[tanjulio]

Okay. Thanks for the replies.

 

It appears that other variables are in play when setting up this racing series.

Honda Challenge; looks like different suspension & transmission setups & driver's skill play into outcomes.

 

I was only looking at a few engines setups when I did the weight to power ratio. Maybe shouldn't have typed 'best' or 'worst'

 

Okay; Follow up question...

Will there be a weight decrease for people who run the DOHC ZC / D 15 engine in 2016?

 

Thanks.

[adamjabaay]

i'd love if they would consider upping the HC D series horsepower caps too... I suspect its because Mid Ohio was the great equalizer, really. on a power track (or pretty much any track but mid ohio), a d series likely isn't the way to go.

 

-I run a D series.

 

ha