[TheSilverBuick]

I've been told that somewhere in the neighborhood of 500 wheel horsepower is where the average street won't hold the power at any speed without prep or very fancy suspension/tire combinations. Basically unlimited burnouts from that point on. Which depending on your driveline efficiency is between 600 and 700 fly wheel horsepower.

Depending on weight, that is essentially a bottom 10's to high-9's car. I personally still have a riot with less.


Which is why junkyard LS's with a turbo on it becomes so popular and fun. It's dirt cheap to make 550whp and have a grin making street burn out machine.

[screamingchief]

Matters if it's gonna be a DD or a "weekend" car to me.

DD then I'd say maybe 450 to 500 fwhp max and roughly the same (or just a bit more) torque.

Weekend only car,all bets are off,as said it's whatever the owner can live with.

And trans type can play into that deal somewhat too,as a manual trans wont have the same set of issues that an auto trans would have & vice versa.

I'd probably never build a 600+ fwhp manual trans car with the goal to drive around on the street myself,as that sorta thing is just not what I'm into.

JMO ~ FWIW.

Bret P.

[1971WARBIRD]

I have seen too much hp/tq for a driver. that is when the driver gets in way over his head and trys to show off all his new power and spins his just finished SS Camero into a telephone pole. good thing it was a chevy.
I have a 71 GTO that will go back together with a built 455 HO hoping to put out around 550- 600hp.

[hurryinhoosier62]

Originally Posted by 1971WARBIRD

I have seen too much hp/tq for a driver. that is when the driver gets in way over his head and trys to show off all his new power and spins his just finished SS Camero into a telephone pole. good thing it was a chevy.
I have a 71 GTO that will go back together with a built 455 HO hoping to put out around 550- 600hp.

I think 450-500hp with 500+ ft/lbs. of torque is a reasonable amount of power for a street car. Much more than that, the car becomes a chore to maintain instead of a joy to drive.
Warbird, say hello to Radcliffe and E-town for me.

[70 bird]

A street car with a turbo is another story. With a 3.08 gear and a tight converter my guess is around 650-700ish? No overheating problems and 15in of vacuum with a 2802 cam. You guys need to get into the boost world!

[ta man]

It all comes down to how the car is setup and the driver..mine is 525 to 550hp..runs mid 11's at almost 119mph...but you would never know it by riding in it or driving it... just don't floor it from a standstill on the street.I routinely drive 1.5 hours to 2 hours to one dragstrip through a major city..and the car drives like a stock 301 and the 3.08 gearing helps on the highway.

[carcrazy]

My 67 GTO is N/A and was 629/609 with 2" headers. Have 1 7/8 now so most likely down some. Will be driving on a regular basis starting late spring. Hoping it is not too much.

[i82much]

I think at about six billion or so horsepower I'd start thinking about detuning it a little bit.

[67GTO4SPEED]

I don't see the point of running any car with any kind of HP on a regular street tire. There are too many soft compound tires and drag radials out there to run BFG Radial T/A's (or something similiar) on a 500 HP car, IMO. That's not to say that any of those tires are going to hook up like slicks, but they a lot better job than regular tires.

[AdamIsAdam]

Originally Posted by dmac

If it idles smoothly and you don't have to worry about it overheating while sitting in a traffic jam, it doesn't matter how much HP it has. It is a street car.

If you need to idle at 1100 rpm, and it exceeds the decibel limit in town, and the temps rise to over 220 degrees when moving in slow stop and go traffic even in mild weather, it isn't really a street car.

That's kinda how I feel.

I'll tell you more about this subject once I take delivery of my new car. I intend to get it dyno'd, but Butler estimated the HP at 500+ and to be honest, I'm concerned it's too much. My friend who built the car said it's extremely reliable, drives fine in the hot southern summers without running hot, etc etc. I intend to cruise the car, and maybe take it to the track 1x/year at most (driving 100 miles each way, no trailering). oh, and drive the hell out of it!

But reliability is priority #1. He says the car is well sorted out and reliable. Time will tell!
(It's got 275 drag radials on it now, BTW)

[b-man]

How much horsepower you can actually handle is the limit.

Some guys can handle 1000+, others might end up in the ditch with only 350.

[goatless]

What does it really matter? I see so many guys that build their car to the hilt and then drive it like my grandmother.

A car only goes as fast as it's driven.

[AdamIsAdam]

Originally Posted by goatless

What does it really matter? I see so many guys that build their car to the hilt and then drive it like my grandmother.

A car only goes as fast as it's driven.

I hear ya. I personally drive EVERYTHING to it's max. Drive it like you hate it/stole it. whatever.

[Firebob]

I agree with the post that said it's too much when you don't want to, or are afraid to, take it out of the garage. The same can be said for blowing a ton of money on it to make it perfect or 110% stock or whatever. It's a car and was meant to be driven otherwise what's the point?

[1978 T/A]

When idle quality and vacuum can't support PB and AC because of a big cam, that is in my mind when you have "too much" non streetable HP.

[Chris65LeMans]

Originally Posted by 1978 T/A

When idle quality and vacuum can't support PB... (non-A/C car) ... because of a big cam, that is in my mind when you have "too much" non streetable HP.

That's what I added hydroboost for.

[TransAm525]

I believe the questions is relative to the vehicle's intended use. If you use your vehicle as a daily driver, as I do, it becomes a factor of how much you're willing to tolerate in terms of idle quality, cruise rpm, fuel consumption, and durability. Without using power adders such as turbochargers or superchargers, it's going to take large cubic inches, large camshafts, and high compression to make the big numbers, all of which have their drawbacks in terms of street manners and operating expenses. For a vehicle limited to car shows and weekend cruises, the limit becomes commensurate to your expendable income.

[Motor Daddy]

Originally Posted by PONTIAC DUDE

A 450 hp engine has plenty of street useable horsepower and you don't have to chase tune ups or drive ability. I build a lot of 400 and 455/400 to 450hp type combos and customers are happy. Pump gas friendly.
But then again there is no replacement for displacement with those numbers.

Put it this way: I bought a set of your cleaned up #62 cast heads (239 CFM), put them on a .060" over 400 and ran 12.84@110.68 first run at 3860 lbs, everything cast!

Signed,
1 Happy Customer!

[PontGuy]

Hey I've got another measure that nobody has mentioned. Might not apply to everyone, but...

Too much power is when your wife, girlfriend, or any other desirable female refuses to ride in the car with you.

Been there.

[Nicks67GTO]

Agreed on the NRE turbo engines. They are nothing more than big dick swinging and are funadamentally useless in a stock style chassis at WOT. Now stick one of those things in a well set up racecar and you would really have something. They are impressive engines. Thats kind of the point of the thread. At what point in the car described in post#1, is it useles power, just for the sake of making a big number and smoke shows?