Hp vs. Weight
06-12-2002, 10:48 AM
#1
Instructor
Thread Starter
Hp vs. Weight
I've been reading many threads about getting more Hp out of a 964 engine. It seems very expensive and questionable as to the actual results. Here are some of my thoughts (Please consider that I am certainly no mechanic or engineer):
The dry weight of a C2 is about 3100 lbs.
The original HP of a C2 is 247 (flywheel)
This gives a number of 12.55 lbs. per HP.
If you were able to get 300 HP from a C2 engine the number of lbs. per HP would go down to 10.33.
This is quite an improvement.
My question is this: Is there a way to remove a LOT of weight (a few hundred lbs.) from a C2 that would give a weight/hp ratio similar to the 300 HP engine, but keeping the stock engine HP.
For example, a 2551 lb. C2 with 247 HP would have the same ratio as the 300 HP stock car. In addition, it would presumably brake and handle better too.
Sorry for the long, rambling post.
Is there anyone who has experience with this?
What do the air conditioning components weigh?
Am I crazy?
Would I be better of taking an early 911 and installing a 3.6?
Thanks.
Mike
The dry weight of a C2 is about 3100 lbs.
The original HP of a C2 is 247 (flywheel)
This gives a number of 12.55 lbs. per HP.
If you were able to get 300 HP from a C2 engine the number of lbs. per HP would go down to 10.33.
This is quite an improvement.
My question is this: Is there a way to remove a LOT of weight (a few hundred lbs.) from a C2 that would give a weight/hp ratio similar to the 300 HP engine, but keeping the stock engine HP.
For example, a 2551 lb. C2 with 247 HP would have the same ratio as the 300 HP stock car. In addition, it would presumably brake and handle better too.
Sorry for the long, rambling post.
Is there anyone who has experience with this?
What do the air conditioning components weigh?
Am I crazy?
Would I be better of taking an early 911 and installing a 3.6?
Thanks.
Mike
06-12-2002, 11:15 AM
#2
Technical Specialist
Rennlist
Lifetime Member
Rennlist
Lifetime Member
A/C components weigh in roughly 50-60 lbs. If you want to get serious, then look at how Porsche stocked their 964 Cup Cars and Le Mans entries. Stark comes to mind, ie, all sound padding out, interior, fiberglas seats, etc. As I recall, the Cup Cars weighed in around 2680 lbs, to give you an idea of weight leverage. Just depends on your purpose and seriousness. Of course dropping a 3.6L engine into an earlier 911 can create a very satisfying machine. Don't forget you'd need to also upgrade the earlier 911's suspension, and probably the brakes, too.
06-12-2002, 01:55 PM
#3
Rennlist Member
Add power or subtract weight; which costs more?
There was a long thread on serious weight reduction on the 996 forum a while back (weeks or months?). 996 owners have a harder time getting cheap small gains in power than 964 owners do.
As Bill indicated, ditching all the A/C stuff and getting light weight seats (and yanking the rears) is a good start. The power steering stuff also weighs enough to yank. You can yank all the carpets and "sound proofing", or get lighter weight stuff, but that doesn't save much. Neither does removing the radio. There are lighter weight exhaust systems, lighter weight wheels (magnesium is lighter than forged alum, and will also lighten your wallet considerably). You can get light weight body panels, and swap out that heavy glass for lexan. You can get a smaller and lighter gas tank and run with less fuel (saving about 6-7# a gallon). If you're overweight yourself, you can go on a diet. In short, you can probably at least approximate the 500# reduction you're looking for, but may end up with an even higher percentage of the mass in the rear. Now you've got a race car; so add back a roll cage, 6-point harness, fire bottle, etc. You can go after the increases in power as well, to make it even faster. I would suggest that you just get a turbo, but I remember someone getting a new twin turbo a while back asking about easy ways to enhance power. Whatever we have never seems to be quite enough.
No, you're not crazy; just a little distorted like the rest of us.
There was a long thread on serious weight reduction on the 996 forum a while back (weeks or months?). 996 owners have a harder time getting cheap small gains in power than 964 owners do.
As Bill indicated, ditching all the A/C stuff and getting light weight seats (and yanking the rears) is a good start. The power steering stuff also weighs enough to yank. You can yank all the carpets and "sound proofing", or get lighter weight stuff, but that doesn't save much. Neither does removing the radio. There are lighter weight exhaust systems, lighter weight wheels (magnesium is lighter than forged alum, and will also lighten your wallet considerably). You can get light weight body panels, and swap out that heavy glass for lexan. You can get a smaller and lighter gas tank and run with less fuel (saving about 6-7# a gallon). If you're overweight yourself, you can go on a diet. In short, you can probably at least approximate the 500# reduction you're looking for, but may end up with an even higher percentage of the mass in the rear. Now you've got a race car; so add back a roll cage, 6-point harness, fire bottle, etc. You can go after the increases in power as well, to make it even faster. I would suggest that you just get a turbo, but I remember someone getting a new twin turbo a while back asking about easy ways to enhance power. Whatever we have never seems to be quite enough.
No, you're not crazy; just a little distorted like the rest of us.
06-12-2002, 03:10 PM
#4
Advanced
Join Date: Dec 2001
Location: NYC
Posts: 62
Likes: 0
Received 0 Likes
on
0 Posts
"Adding Lightness" Costs Big Bucks.
But if you're gonna do it, do it like Jim Calzia:
<a href="http://early911sregistry.org/jCalzia.html#Calzia%20article,%20top" target="_blank">http://early911sregistry.org/jCalzia.html#Calzia%20article,%20top</a>
Good luck!
But if you're gonna do it, do it like Jim Calzia:
<a href="http://early911sregistry.org/jCalzia.html#Calzia%20article,%20top" target="_blank">http://early911sregistry.org/jCalzia.html#Calzia%20article,%20top</a>
Good luck!
