Weight savings -- free horsepower?

DeHaldaswerth · 9 April 2001

First, I have already studied the FAQ on this topic.

My calculations indicate that on the NSXt 6 speed, the power to weight ratio is 10.91 pounds per horsepower. It therefore seems clear that for every 11 pounds I remove from my car, I "add" the equivalent of one horsepower, without the complicated engineering/longevity questions of engine modifications. In fact, I might actually be enhancing the longevity of my NSX by reducing its weight and thus the work it has to do while hauling me around Northern Arizona.

Anyway, I've done a little research on weight reduction, and I conclude that I might be able to shave up to 200 hundred pounds off the weight of the car with a relatively small investment. (All of the modifications I have contemplated are reversible for those of us in the bone stock crowd) The weight reductions would include the following:

Removal of engine cover
Remove front spare tire and mount
Remove jack, compressor and tools
Replace battery with smaller dry cell
Replace rear exhuast with straight pipes
from the cats to the rear valance (LOUD!)
Replace factory seats with MOMO buckets
Remove power antenna, replace with fixed
unit similar to that on s2000.
Remove about twenty pounds from my belly.

My question -- have any of you out there experimented with weight reduction and its actual, real world impact on performance? Do you have any numbers to share? Testimonials?Do you think I will be able to feel the change in the seat of the pants (acceleration, cornering?)Have I overlooked any other easy weight reduction ideas?

nel · 9 April 2001

Originally posted by DeHaldaswerth:
My question -- have any of you out there experimented with weight reduction and its actual, real world impact on performance? Do you have any numbers to share? Testimonials?Do you think I will be able to feel the change in the seat of the pants (acceleration, cornering?)Have I overlooked any other easy weight reduction ideas?

You may s(h)ave another 40lbs if you can fab (using aluminum) the front and rear re-inforcement bars (71530-SLO-AD0) or as done with Doug's NSX. See Chapter 39 on http://www.nsxfiles.com/stories.htm for pictures.

I'm very interested in these bumper beams myself. If anyone (besides Doug) has done this sucessfully, please share...

-Nick

FAQ Nazi · 9 April 2001

Do you have any numbers to share?

Check out the last column of the chart "What are the numbers?" in http://www.nsxprime.com/FAQ/Performance/gears.htm

You are correct that reducing 200 pounds will have about the same improvement in acceleration as adding about 18 hp, which will improve 0-60 times by about a third of a second.

Will you be able to notice that on the street? Maybe. Maybe not. Will you be able to notice it in any measured track activity? Probably.

ilya · 9 April 2001

A third of a second is very significant. I would spend a lot of money to pull 3/10 off my 'potential' 0-60.

As for the beams, I just mentioned this in another weight thread yesterday. It's funny actually. Larry was just telling me about this weight savings on Saturday that he found by switching the bumper beams while working on Doug's car.

I'm dying to find out how much it will cost. I'll pay up to a few hundred dollars to pull 40lbs off the car, especially when there is no visible difference. He said more like 70lbs, but he was just estimating... he's probably overestimating.

NSXGOD · 9 April 2001

Originally posted by ilya:
A third of a second is very significant. I would spend a lot of money to pull 3/10 off my 'potential' 0-60.

As for the beams, I just mentioned this in another weight thread yesterday. It's funny actually. Larry was just telling me about this weight savings on Saturday that he found by switching the bumper beams while working on Doug's car.

I'm dying to find out how much it will cost. I'll pay up to a few hundred dollars to pull 40lbs off the car, especially when there is no visible difference. He said more like 70lbs, but he was just estimating... he's probably overestimating.

Hi Ilya,
Well, here is the info you need - I will refrain from making any comments that I might be thinking about Larry's price estimating skills.

Front Bumper Piece:
$391.12 List / $293.34 Dali Price
Rear Bumper Piece:
$614.94 List / $461.21 Dali Price
or both for $740.00 Dali combo price

all prices plus labor and tax in CA of course - if larry can do that for "a few hundred dollars" as you quoted him before, I'll be next in line after you. I'd bet that if you got out the door for $1,000.00 it would be a killer deal.

JMO,

------------------
need more info? please private me @

[email protected]

Mark Johnson, CEO of Custodial Services @ Dali Racing, a Not For Profit Company.

ilya · 9 April 2001

If it cost that much I wouldn't do it. He mentioned something about having some factory nearby that does the cutting for free. He needs to supply them with a piece, and they will duplicate it at no charge... he just pays for the aluminum block.
If it ends up being that expensive, I won't go for it. I hope there is a way to get this done for less. If it could be done cheaper it's a great way to save weight. I told him if it costs me less than a few hundred dollars I'd be his first customer, so we'll just have to wait and see what happens.
I know there are people who track their NSX that would pay over 1K for that reduction in weight, but I can't justify a cost like that.

DeHaldaswerth · 9 April 2001

Price is usually the issue when one starts examining exotic ways to reduce vehicle weight. However, the good news is that I think I can shave the weight I've described in the initial post for less than $1500. If I could drop my 0-60 times from, say 4.8 to 4.5 for $1500, plus reduce the amount of dead weight that the car carries on those county drives, I would feel like I had accomplished a great deal. The one caveat is the exhaust -- sure is cheap and light to use straight pipes, but I'll probably only be able to use them occasionally.

FuzzyGreenCarpets · 9 April 2001

You guys are a little off on your estimate about how reducing weight will affect performance. It effect is actually greater. Because it is an exponential rate. For instance if you remove 100 lbs form a 3000 lbs car you just reduced the weight by 3.3%. If you remove 100 lbs from a 2000 lbs car you just removed 5%. So figuring that 11 lbs will equal one horsepower is a little conservative because the more you remove the more HP it will be worth.

Steve
<a href="http://www.mp3.com/fuzzygreen">The Fuzzy Green Carpets</a>

[This message has been edited by FuzzyGreenCarpets (edited 09 April 2001).]

nsxtasy · 9 April 2001

That's true - but it's a good approximation, because you're not likely to get an NSX down to 2000 pounds. If you succeed in getting your NSX down to 2700 pounds curb weight, then at that point removing another 90 pounds will have the same percentage weight reduction as removing 100 pounds from a 3000-pound car (the approximate curb weight of the stock coupe). Not that big a difference.

nel · 9 April 2001

Originally posted by ilya:
...If it could be done cheaper it's a great way to save weight. I told him if it costs me less than a few hundred dollars I'd be his first customer, so we'll just have to wait and see what happens....

ilya,

Please keep us posted if your source can produce the beams that cheap. I'm very interested. Thanks.
-Nick

ilya · 9 April 2001

I just spoke to Larry again regarding this. He has a welder that works with him in the near vicinity that does this kind of work. He explained that he did this for Doug cheap this way without paying for Acura parts from a dealer.
He's looking into it and will let me know.

As soon as I know, rest assured I will post it up (and be down at his shop within the hour).

ilya · 10 April 2001

On a related note, a link to this part of the FAQ may give some more ideas on weight reduction. For those of us nuts who would pull out the power steering to save 32lbs.

It goes over most of what was deleted from various models (NSXR, Type S, Zanardi, etc) and how much each reduction saves. http://www.nsxprime.com/FAQ/General/modelinfo/modelinfo.htm

uh oh... do nsxtasy and the FAQ Nazi have competition now??? Don't worry.. I won't make a habit of it.

FAQ Nazi · 10 April 2001

uh oh... do nsxtasy and the FAQ Nazi have competition now???

No, because there's already a great section in the FAQ on weight reduction, and here's that link: http://www.nsxprime.com/FAQ/Performance/weightreduction.htm

ScienceofSpeed · 10 April 2001

Here's some numbers I'm looking at: http://www.scienceofspeed.com/project_nsx/weight_reduction.htm

My goal is 2750 lbs this summer.

Remember -- less mass = better stopping power, an added bonus.

-- Chris

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www.NSXClassifieds.com - The internet's only exclusive NSX Classified site!

sjs · 11 April 2001

If the torrential rains, hail, and threat of tornadoes ever end around here I'll get out and do some acceleration runs on a smooth level road, with and without some ballast, then post the G curves. Meanwhile, I recently did some runs a few days apart, one day alone and the other with a buddy who weighs about 210. I ran on the same stretch and weather conditions both days were similar.

Time to 60 differed by 0.2 - 0.3 seconds, quarter mile by 0.3 - 0.4 sec and 3-4 mph. Perhaps a better measure is the acceleration Gs because it eliminates some driver variables. With the extra weight, acceleration appears to drop by .03 to .04 Gs throughout, which is consistent with the times. And yes, the SOP difference is very perceptible, but don't take my word for it, take a buddy for a spin, then kick him out and repeat.

Remember -- less mass = better stopping power, an added bonus.

And let's not forget the corners! Less weight = more lateral G potential.

ilya · 12 April 2001

There is a good chance I will find out the cost of the beams during the NSXCA meeting tomorrow in SoCal.
From what he says, there is no way it'll be more than $200-300 per beam and the install is a half hour to an hour job for him. We'll see. I'll believe it when they're on my car and the cash is paid. I am very hopeful though and am looking forward to it.

Remember, these are not factory beams. He has a guy he works with who is duplicating the factory beams for him.

maomaonsx · 12 April 2001

OK, but what is the strength level of these copied parts? Would they offer the same level of protection in a collision? If the answers are yes, then I'm all for it!

------------------
http://clubs.yahoo.com/clubs/maomaosnsxmodclub
My club for infos on my NSX.

ilya · 12 April 2001

I'll make sure to ask that at the meeting tomorrow. My gut feeling is they will be equal in every way, but I'll keep everyone posted. Larry is a perfectionist in the very meaning of the word. He would never put inferior parts into an NSX. I had him talk me out of a couple other ideas for this very reason. He tried to convince me not to start pulling out the AC and other parts because I wasn't racing it and started come up with other weight reduction ideas for me such as the beams.
He either goes full bore or not all so I would expect this to be the same. I'll post on Friday after the meeting.

ilya · 13 April 2001

Larry won't have the final price until the beams are done later today or this weekend, but I spoke to him about the safety concerns yesterday. He said they will be exact replicas using the same aluminum. It will be as thick, or thicker than the stock beams. He said he doesn't like to play around with that stuff and it will be equally durable, if not moreso.

As a side note, I took pictures of the NSX Dune Buggy Larry is building in his shop. AWESOME! I just gave the film to a 1 hour photo development. I will scan and post the pics within a couple hours.

I also took some other cool pics yesterday, but I don't want to post pics of other people's cars without their permission. For example, Doug was there in his F355.

And Alex V's always sweet GruppeM machine.

ilya · 13 April 2001

In case you didn't see it in my obvious sandrail post, here is the pic of an NSX engine being used in a Sandrail/ Dune Buggy.

ilya · 13 April 2001

Yes, that's an F355 parked in the distance. What do you think I used the rest of my film on?

I didn't want to post pics of other people's cars without their permission, but it ended up in the background by accident.

ScienceofSpeed · 13 April 2001

ilya - you say that the beam will be made out of aluminum just like the stock ones. My impression was that they were made of steel.

-- Chris

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www.NSXClassifieds.com - The internet's only exclusive NSX Classified site!

maomaonsx · 14 April 2001

Chris, the later NSX (not sure snce when, probably when the targas came out) used aluminum beams to save weight. You can get the OEM parts to replace the steel ones, but they are very expensive.

------------------
http://clubs.yahoo.com/clubs/maomaosnsxmodclub
My club for infos on my NSX.

Lud · 14 April 2001

The bumper reinforcement beams changed to aluminum in '95 to help offset the added weight of the -T.

You could probably pick them up from a junk yard for cheap as long as the car wasn't hit on whatever end you are buying.

nel · 1 May 2001

Originally posted by Lud:
The bumper reinforcement beams changed to aluminum in '95 to help offset the added weight of the -T.

You could probably pick them up from a junk yard for cheap as long as the car wasn't hit on whatever end you are buying.

An NSX friend of mine just got a quote from Tracy of Gunn Acura: the cost for a 95+ rear reinforcement beam (71530-SL0-A01) is $461.21 (list for $614.94--price subject to change per Tracy). This is Acura OEM part so we don't have to worry about its structural integrity.

Does anyone know how much the aluminum beams weigh vs. the steel ones? It might be a sensible mod if I can take off more than 40lbs off my NSX by simply swapping in an OEM part.

-Nick

(Oh, the usual stuff: I have no financial interest in this... yadda yadda yadda...)

Weight savings -- free horsepower?

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