How much is 5% more horsepower worth at rear wheels

[V10_P70]

Let's assume that you are making 250 rwhp and want to increase the amount 5%. How can you do this and what are the costs involved? One way of doing this is to change the driveshaft to Carbon Fiber. This result has been published in several journals. Is this worth $200 over the aluminum or MM shaft replacement that has been popular with the rear-end gear change?

This is only looking at the HP, not the safety or driving difference with the shaft. Just a thought.

[RF Overlord]

V10:

This has been discussed here as well as other forums...the driveshaft will not increase your rear-wheel HP, it's just lighter and stiffer so it allows the car to accelerate a very small amount quicker (less rotational mass)...

Is it worth $200 purely from a performance standpoint?...only you can decide that, but I would say no...just like underdrive pulleys; they add a very slight performance boost, but IMHO are not worth the money...doing both might result in a detectable performance increase, but for the $350-400 cost, there are other things that would give greater increases...

[V10_P70]

Look at this link for validation of the shaft performance:

www.acpt.com/driveshaft/driveshafts.html

Also, will post the dyno results using 4 wheel eddy chassis dyno using our V10 Crown Victoria.

[SergntMac]

Ditto to RF, that's the word, and well said too.

Eddy-current dynos are inaccurate and inconsistent, they do not reproduce similar test results in back to back testing. I have a Mustang eddy-current dyno report sitting right here that "proves" that my MM has 365 RWHP, and 1310.8 ftlbs. RWTQ! Should I believe this report? I watched the tests carefully as they were conducted. The technician-operator is an ASE certified wrench, and factory trained. I paid a lot of money for this test...Should I believe the dyno results? Please tell me?

Before I will determine if any HP/TQ gains are worth any cost, exactly what will this shaft cost me?

[RF Overlord]

Originally posted by SergntMac
I have an Mustang eddy-curret dyno sheet sitting right here that "proves" my MM has 365 RWHP, and 1310.8 ftlbs. RWTQ!

Sarge are you sure you own a Marauder and not a Merlin?

[V10_P70]

We have different ideas about vehicle dynamics and acceleration. Just makes you wonder how we did 150 mph and .88 on the skidpad.
:banned:

[Menace]

U got shafted ?

[SergntMac]

Well then Bucko, let's "put up or shut up?" Nothing more efficient in the pitch than adding more smoke to peek through, eh?

Before you tell me how much this driveshaft will cost me, or, proving how much HP/TQ numbers (not percents) I may expect to see for my money, explain to me how your driveshaft has ANY effect on skid pad gForces...please? Begin anytime...

You think we have different "ideas"? I agree. My ideas are about "bang for my buck" and what I should expect for my money. My point here, is that NO ONE reading anything on this site should be encouraged to spend their money without proof of benefit first, or, at the very least, be provided with clear and definable facts they can examine on their own.

When you can meet this simple standard, post your suggestion. Expect us to check you out. If you're at least 50% close to your boast, the readers here will surely decide for themselves. We are a "tough room" yes, thanks to a few Impala SS dudes and some real time resident "run tuffs." Short them...and you get the bad day.

"5% RWHP gain for 200 bucks"
"Eddy-current dyno"
"Skid pad .88"
"150 MPH"

Not much for me to wonder about at all.

Go away already.

[V10_P70]

http://www.caranddriver.com/xp/Caranddriver/features/2002/july/200207_specialtyfile_intercept or.xml

[SergntMac]

And this has what to do with your opening post?