Weight to BHP comparison

[Race Grandpa]

I did a comparison of Weight to BHP for my Eunos Roadster and other high performance cars.

This is based upon a FFS with 120mm pulley, which I expected I would buy. However, the 110mm pulley gives me more power than I need.


Since, there is no factor for torque or gearing the comparison may not have a lot of validity.

However, I will use it to show my son-in-law's friends who have WRXs & EVOs. Few of them do not know more than their cars' BHP - the WHP, torque & gearing are things that are over their heads!!! :ack2:

For what it is worth I have attached the file.

:rockon:

[Race Grandpa]

I tried to attach my Excel file with no luck.

Is there a way to do this?

[Tom @ Fast Forward]

The neat thing about the FFS kit is the 150 ft-lbs of RWTq @ just off idle. ;-) Compared to a stock Miata @ ~35 ft-lbs.

[Race Grandpa]

The neat thing about the FFS kit is the 150 ft-lbs of RWTq @ just off idle. ;-) Compared to a stock Miata @ ~35 ft-lbs.


Another Dumb Question.

Since the SC is not producing any boost at idle, why is there a difference???

[Tom @ Fast Forward]

Yep. You have to actually have the engine under load to make boost. That's why I used the phrase 'off idle'. You have to get it rolling. I also set the PC-_Prs to start adding fuel above 1200 RPM.

[Kyp J]

Yep. You have to actually have the engine under load to make boost. That's why I used the phrase 'off idle'. You have to get it rolling. I also set the PC-_Prs to start adding fuel above 1200 RPM.

I was wondering why my car was so slow at 1100 RPM.

[Race Grandpa]

File size prevented uploading the doc

Here it is. Hope my fingers type the correct numbers. In case they do not,
I can not guarantee the accuracy of this data. Regardless, I not not assume any liability for this data or the conclusions contained herein.

Comparison of Weight-To-BHP is Based upon 1) Race Grandpa's 1997 Euno's Roader with FFS Coldside, 120mm Pulley, Magnaflow muffler/CAT & weight of 3,265 lbs. AND 2) Other Base Model Cars



Car: Ratio % Comparison
Grandpa's Race Car 9.0
Shelby Mustang 7.8; +15%
Corvette Z06 7.1; +11%
Lotus Exige 9.5; -6%
EVO 11.5; -22%
Porsche Cayman 11.7; -23%
WRX 14.3; -37%

[bogey]

Race Grandpa's 1997 Euno's Roader with FFS Coldside, 120mm Pulley, Magnaflow muffler/CAT & weight of 3,265 lbs.


I am glad I have a 96. It is considerably lighter than the bloated 97. Mine weighs about 1000 lbs less! ;)

[mageep]

A couple questions / thoughts...

1. I hope you weight was a typo! Without my fat ass in it, my 99, which is noted to be heavier thatn any M1 hits the scales at 2300.

2. Are you comparing apples to apples with your figures, either crank to crank or wheel to wheel outputs? I ask because you'd either need ot conservatively deduct 18% off of factoey HP claims to make it similar to WHEEL HP, which is what your dyno likely gave you, or MULTIPLY yours an equal amount to make it match factory claims...

Impressive either way, but if you're using yours as Dyno wheel HP, and theirs as FACTORY HP / WEIGHT numbers, you're selling yourself VERY short! ;)

[Tom @ Fast Forward]

My 99 is 2440 with a full tank of gas and my Boss Frog rollbar.

If you add 32 HP you should be close to crank.

[99mx5]

mageep, the 99 Sport was known as one of the lightest of the NBs.

[mageep]

mageep, the 99 Sport was known as one of the lightest of the NBs.

Ohhh, I hear ya, and I know that quite well! :devil: I sought out the one I have for 6 months. The only 'factory' weight-adder it has that I could have legally removed and been C-Stock legal was AC. Mine has manual windows, locks, seats, no cruise, etc... a stripper!

And sadly, at National events, there were still guys coming in at 2225... about 75-80 pounds UNDER me!
I could only ever track down about 50-60 of those 80 pounds. The other 20 was a bit of a mystery.

[Race Grandpa]

I am glad I have a 96. It is considerably lighter than the bloated 97. Mine weighs about 1000 lbs less! ;)

Oops! Should be 2,350 lbs :redface:

At 57 I must be in early stage of Alzheimers!!!

[Race Grandpa]

A couple questions / thoughts...



2. Are you comparing apples to apples with your figures, either crank to crank or wheel to wheel outputs? I ask because you'd either need ot conservatively deduct 18% off of factoey HP claims to make it similar to WHEEL HP, which is what your dyno likely gave you, or MULTIPLY yours an equal amount to make it match factory claims... ;)

I used a conversion factor of 1.17 to get the BHP from WHP. I hope that is right. But again I am in the early stages of Alzhemiers.

[Race Grandpa]

mageep, the 99 Sport was known as one of the lightest of the NBs.

On the track section of the Miata.net forum there are guys that are tearing things out that only amount to about 10 lbs. I am pretty sure that they only track their cars. So why do they go to all the trouble?

One guy removed his radio, which may have reduced the weight by 10 lbs.

Lets see, if you reduce the weight by 30 lbs on a car that originally weight 2,300 lbs the weight was reducted by 0.013%.

I wonder if they thought about taking off their badges???

:no:

[jwalton]

There's a saying in the motorcycle world about people spending big bucks on saving a lb or two...

"It's a lot cheaper to go on a diet, and far more effective, than buy something that reduces the weight less than the poop (for our younger readers) you took this morning!!!"

[mageep]

There's a saying in the motorcycle world about people spending big bucks on saving a lb or two...

"It's a lot cheaper to go on a diet, and far more effective, than buy something that reduces the weight less than the poop (for our younger readers) you took this morning!!!"


LOLOL.. While I agree (and at 220 can take it seriously!!), it's all about the Colin Chapman principle.

If I can knock 100 pounds off, I reduce the car's weight by 4%. While that sounds pretty petty, consider that it's not just 4% toward acceleration, but also braking and cornering. So you have to spend $$ in 3 categories to get the same benefit of making an upgrade in ONE, and if you do it right, it's FREE! :)

Is that crazy? Maybe, but many would argue so is a 200WHP Miata! :devil:

[Tom @ Fast Forward]

While true, I (at 220#) would feel a lot better if I could drop 50 of that 100# and then take the other 50 out of the car. :) But, hard as I have tried, I think taking 100# out of the car would be a LOT easier.

[mageep]

While true, I (at 220#) would feel a lot better if I could drop 50 of that 100# and then take the other 50 out of the car. :) But, hard as I have tried, I think taking 100# out of the car would be a LOT easier.


+1 :)

Tom thinks a lot like I do.

[Race Grandpa]

Oh no I made a mistake - how can that happen? :taz:

My race car's weight/BHP ratio is 9.6

Way Way to old to go on a diet. I think I have reached my natural weight. On the other hand, Tom is a lot lot taller than I am.

[Tom @ Fast Forward]

Oh no I made a mistake - how can that happen? :taz:

If you worked for FM, you wouldn't have that problem. ;)