How fast is too fast for a street car? *SERIOUS DISCUSSION*

Killercanary

The car that set the bar.
Founding Member
Nov 29, 1999
5,676
1
76
Altoona, PA
How fast is too fast for a street car? This is a question I have been pondering a lot lately and everytime I think I have my mind made up to the answer, something makes me change it. I look back over the years of moding my car and I remember WAY BACk in '97-'98 thinking that if I could have a street car that would run 13's it'd be "fast enough." Then I started adding mods until I got into the high 13's but I then realized that it really wasn't that fast. So the cycle continued and I added my heads, cam, and a few other parts hoping to run low 13's, and the car ended up running all the way down into the 12.0 range. Thinking I'd be happy with that it soon dawned on me that while I do have a "quick" street car, but its not "fast" relative to the other cars around here, especially concidering what some of the OEM stuff is running off the showroom floor these days. Around this time is when I hurt my car and I have since been planning my next round of mods, but now I have to a cross roads and the question again is coming up, how fast is too fast, and this time it is a little different. At this point my options are limitless in terms of what I do to the car, but it snowballs out of control rapidly. I could always add a high compression 347 or even a 393 to my car and pick up maybe 100 more RWHP, but I don't think that's enough to bump me into the "fast" category as the car would still be slower than most here run on a stock shortblock with H/C/I and a vortech. I could add a turbo or supercharger to my car and lay down ~500rwhp, and from where I stand I think that would be on the verge of a "fast" street car, but then you get into needing a new fuel system (which opens you up to making up to ~900rwhp), a new stronger block (which opens you up to making >900rwhp), a stand alone etc.(these are parts that I consider mandatory at this level, I know some try and do it with the stock stuff but I wouldn't if I was in this position) and if you are going to go through the expense of doing all of that why just build a stock displacment, why not stroke it, add better heads, a bigger supercharger, etc? I got caught up thinking about these magical builds and when it was all done and I sat back and looked at what some of the things I created on paper would produce, I think they would all be TOO fast for the street. I mean, my 300rwhp car will only spin the tires in 1st gear when its cold out, after that I can got WOT all day in every gear and not think twice about it, however what would happen with 450, 500, 550, etc RWHP? This got me thinking what would be too much for the street? A dart based 347 with a good H/C/I and a turbo can make over 600rwhp, is that too much? A 150 shot on a high compression 347 could make ~500rwhp, is that too fast? I know we all at some point think we'd all love to have 1000hp daily drivers, but I think most of us know that its just not reasonable to have so much power on tap IN A STREET ONLY CAR. A few might disagree, but I'd like to hear what you all think.
 
  • Sponsors (?)


THis is a pretty difficult question to answer...it really depends on a few things...like how much you drive, the weather, smog exemption/certification, wallet, and um...yeah...WALLET! Sure you could build a bad ass 393 with a blower...blah...blah...blah, but if it only gets 3 mpg and you drive it all the time, its gonna cost! My car...which by no means is "FAST" goes 11.90's on the motor. I dont drive it on the street though, I havent insured or registered it because of the lack of funds for gas...gas...gas...and the possible tickets. I will get it back on the road soon, but driving it compared to driving the wife's scion tc is like night and day. power steering, ac, being able to cruise at slow speeds without bucking, those are all long gone in my car. I will drive it...I even like to drive it...but in the rain or on a daily basis...i'll either end up broke...or dead! my .02.
 
First of all....a 12 second car IS a fast street car. Even though you're used to it, a low 12 second car like yours was will beat down just about anything on the street randomly encountered, and is definitely will be in the upper echelon of any organized street or street legal event.

As far as too fast for the street, I don't think it's the amount of horsepower/ET potential that the car has that limits it's streetability. It's all in the combo and the manners it displays; ie I remember reading about Lidio Lacabelli's 9-second street Mustang that displayed outstanding street manners and even got fairly good gas mileage.

I guess that the problem your thinking of is if your interested in truly street racing it; yes, you may have a VERY fast Mustang that is easy to drive around in and lays down 11 or even 10 second track times on the weekend...but on your street tires, you'll be taking losses to cars that are considerably slower at the track (like your average 12 second street 5.0) because they can actually get into it while you spin.

I'd think that for a true street car on radial tires (be they BFG or MT drag radials), you won't have much success in random street action past the 450-500 RWHP range as past this it seems to be total tire oblieration for normal sized street rubber with street suspension at this point...

Just some rambling. :lol:
 
Killercanary said:
I mean, my 300rwhp car will only spin the tires in 1st gear when its cold out, after that I can got WOT all day in every gear and not think twice about it.

How the hell did you do that? Seriously, my car isn't near the 300 mark yet, has 315/40/18 Goodyear Eagle F1's, and I blow them off if I hit it too early in second gear. I know them being 18" doesn't help, but I would still think they should grip a lot better than stock considering they come stock on the rear of Vette's. Please give me an exact list of your set-up, so I can copy you :D .
Brandon
 
i don't think that the street car term has anything to do with how fast your car is but more with the comfort/ reliability and economics. as long as you can make the power without sacrificing those i would still consider it a street car. obviously a car that makes that much power is going to use up more gas. also pump gas is a requirement for any street car. i think a turbo is the best solution for insane power while still retaining drivability. you can run two tunes with the turbo. one for pump gas and one for race gas.
 
mootang said:
i don't think that the street car term has anything to do with how fast your car is but more with the comfort/ reliability and economics. as long as you can make the power without sacrificing those i would still consider it a street car. obviously a car that makes that much power is going to use up more gas. also pump gas is a requirement for any street car. i think a turbo is the best solution for insane power while still retaining drivability. you can run two tunes with the turbo. one for pump gas and one for race gas.

I was coming back to offer an on topic response :D , and this pretty much somes it up. I would be comfortable in a 1000+hp twin turbo something if it had a good idle, no overheating issues, conventional style tranny, and you didn't need to be a bodybuilder to work the clutch in traffic.
Brandon
 
Paul, your smart enough to know that the more suspension crap you have done to your car (particularly in the rear), the more power you can put to the ground "safely" on the street. But there comes a limit...obviously.

Supercharged and nitrous cars take RPM to make power. RPM isn't really your friend on the street, especially when talking safety. RPM = speed, and more speed = more unsafe.

I like the 302 stroker combinations because you can give them enough "go" for a street car. 10's isn't a problem with a good, streetable 347. And I think anything faster than that gets too expensive and begins to slip into the "unsafe" catergory. Plus, what other street cars are running 10.9's or better in your area? I wouldn't think too many.

In your situation, and your uncertainty, your best solution may be to build a DART based 4.000 or 4.125" block with a 3.400" crank. That way, if the speed bug bites you, you have the foundation of what you need (Dart block) and can always add to it later.

----After reading all that I wrote, I kinda don't make sense. It's just a bunch of my jumbled thoughts thrown all over. But I hope it helps. :D

Joe
 
SQUEEZE&STROKE said:
THis is a pretty difficult question to answer...it really depends on a few things...like how much you drive, the weather, smog exemption/certification, wallet, and um...yeah...WALLET! Sure you could build a bad ass 393 with a blower...blah...blah...blah, but if it only gets 3 mpg and you drive it all the time, its gonna cost!


You are right that it all depends on the person and their situation. Lets take mine for example:
1. I drive the car up to but no more than 5000 miles/year. I drive it to the grocery store when its nice out, to car cruise-ins, car shows, races, etc. Basically its not a DD but it's not a garage queen either. Its only driven on nice days though.
2. No emission requirements since I fall into the <5000miles/year catagory.
3. Wallet, well lets just assume that money isn't an object (it is of coarse, but for the sake of determining how fast is too fast let's leave it open)
4. MPG... that's a hard one. I have seen guys knock down 20mpg with over 500rwhp with turbo cars, and others only get single digits to teens with big cube'd NA motors. Personally I'd like to get 15-20mpg out of whatever I build.



Guys although streetability is a huge factor here, I'm looking more for a discussion on SPEED and horsepower as in 700rwhp is too much IMO for a street cars that even with a killer suspension and monster tires would still be able to lite the tire up at 70+mph. Basically, how fast is too fast in that it'd be more scarey than fun?


I guess that the problem your thinking of is if your interested in truly street racing it; yes, you may have a VERY fast Mustang that is easy to drive around in and lays down 11 or even 10 second track times on the weekend...but on your street tires, you'll be taking losses to cars that are considerably slower at the track (like your average 12 second street 5.0) because they can actually get into it while you spin.

I'd think that for a true street car on radial tires (be they BFG or MT drag radials), you won't have much success in random street action past the 450-500 RWHP range as past this it seems to be total tire oblieration for normal sized street rubber with street suspension at this point...

This is EXACTLY what I'm thinking and trying to discuss. I can tell you right now that I wouldn't feel comfortable driving around with my wife and child in a car that can lite the tires up at 75mph, that's just a recipe for disaster and too much for me. What is it for the rest of you?


Also, I am not looking at this from a street racing standpoint though, just a "how much is too much" for you to handle in a car that is driven on the street.


ROLLIN5.0- a lot of it has to due with the weight of my car, the 315 series tires, my suspension, and the powerband of my combination. It would spin the tires a LOT more when I had the stock heads and cam in the car than now since I have changed all of that.

i don't think that the street car term has anything to do with how fast your car is but more with the comfort/ reliability and economics. as long as you can make the power without sacrificing those i would still consider it a street car.

Don't get hung up on the street car term here. For sake of argument lets say the car idles at 650rpm, gets 25mpg, cold AC, runs on pump gas, etc. which leaves us only with how fast is too fast. Like I said above, I wouldn't want a car with enough power to spin the tires (drag radials, ET streets, whatever) at 75mph, that is too fast IMO for a street car. What do you think?
 
Joes95GT said:
...
Supercharged and nitrous cars take RPM to make power.
...
of course, the twin-screw type of blower is an exception to that rule.

to the topic, 500hp seems to the the current number for defining fast street cars. case in point, the new vette and the new viper.

for me, i don't want a roll cage, as far as track times, i'd want it as fast as possible without having to put a cage in, whatever that is.
 
Joes95GT said:
Paul, your smart enough to know that the more suspension crap you have done to your car (particularly in the rear), the more power you can put to the ground "safely" on the street. But there comes a limit...obviously.

EXACTLY! But where is that limit? That is the biggest thing I am trying to determine.

Supercharged and nitrous cars take RPM to make power. RPM isn't really your friend on the street, especially when talking safety. RPM = speed, and more speed = more unsafe.

For me and my street car, I too don't like RPM. I will build something that is shifted no more than ~6000rpms MAX. It getts too expensive replacing valve springs, as well as the additional stresses and wear on everything else when it comes to a high rpm motor.

I like the 302 stroker combinations because you can give them enough "go" for a street car. 10's isn't a problem with a good, streetable 347. And I think anything faster than that gets too expensive and begins to slip into the "unsafe" catergory. Plus, what other street cars are running 10.9's or better in your area? I wouldn't think too many.

I feel the same way about 302 stroker combos. When you say a streetable 10 second 347, are you refering to a NA one? If so I disagree, at least in terms of the 347 I'd need to build to get my car into the 10's. As for how many 10 second cars... there are at least 5 mustangs that run 11.1's or better and I can think of and a bunch of 500rwhp imports that I know of just off the top of my head. Things have really changed in the last few years in terms of the caliber of cars encountered on the street around here.

In your situation, and your uncertainty, your best solution may be to build a DART based 4.000 or 4.125" block with a 3.400" crank. That way, if the speed bug bites you, you have the foundation of what you need (Dart block) and can always add to it later.

All I have to say is :D and good minds think alike.


----After reading all that I wrote, I kinda don't make sense. It's just a bunch of my jumbled thoughts thrown all over. But I hope it helps. :D

Joe

It made perfect sense to me!
 
Paul, sounds like what you had, with a strong but basic bottom end, and a 175 shot would give you exactly what you're looking for... :)

It wouldn't be too wild (dangerous) for the street and you'd have the power on tap to run the low ETs you're looking for.
 
heres my take on this....take what you wish because im still really only stock but here....as a 17 yr old new driver when i first got my car, never really having driven any other performance cars, i thought my car was fast, and i still think its somewhat quick......since the car is my DD i would probably be happy with 300-350 hp and call it a day...its enough to run 12's on DR's, and still could knock down 20mpg (give or take)....

NOW, idk if you read my thread about driving my dad's chevelle for the first time, but i gained a new found respect for "fast"....as much fun as this car was to drive (probably because it was a novelty for me) this car was borderline too fast for a reliable street car....at 55mph in 3rd gear (auto) i melted the tires off at 1/2 gas, and the car went sideways....im in NO means bragging here, just making a point as to the fact that anywhere around 650hp or so is getting close to TOO dangerous on the street......

i DEFINATELY agree with Joe on this idea of the dart block, so you can build on it.....i'd maybe do a mid-low compression 331 or 347 (i say 331 because of cylinder wall thickness) in the dart block, with some killer heads (afr 205's???), victor junior intake??, and an eddie c grind.....at around 400 hp, you could say "Hmmm this is about 70 more hp than i have now....." and decide if you think its fast enough (which it NEVER is:D ) or throw a blower or a turbo on it when money would provide....

again take this info as you wish because im still young and learning, but i have planned out a lot, and i've thought about this EXACT same issue lately after driving the pops car.....good luck buddy, and keep us updated:nice:
 
stprorolla49 said:
NOW, idk if you read my thread about driving my dad's chevelle for the first time, but i gained a new found respect for "fast"....as much fun as this car was to drive (probably because it was a novelty for me) this car was borderline too fast for a reliable street car....at 55mph in 3rd gear (auto) i melted the tires off at 1/2 gas, and the car went sideways....im in NO means bragging here, just making a point as to the fact that anywhere around 650hp or so is getting close to TOO dangerous on the street......

(i say 331 because of cylinder wall thickness)

The part in BOLD above is exactly what I'm trying to discuss and avoid. I think that is too fast, but this is what I want all of you to think about and post about. Again, how fast is too fast in that its too scarey and dangerous to be fun anymore?

As for wall thickness, the dart blocks can be bored to over 4.185" but anything larger than a 4.125" bore is a custom only piston.


Paul, sounds like what you had, with a strong but basic bottom end, and a 175 shot would give you exactly what you're looking for...

It wouldn't be too wild (dangerous) for the street and you'd have the power on tap to run the low ETs you're looking for.

Although I totally agree with your thinking, I have no plans to ever run nitrous in anything I drive, unless I use it as an intercooler. :)
 
going back to lidio, i live in michigan about 7 miles away from his shop. the thing is i think you can have a 9 sec car that is very streetable depending on the tune you have. lidio has an article on his website about people tuning there cars for maximum HP from the setup they have. his complaint is that when you max out HP for your setup you risk durability and streetablity. i worked with a guy that had a 93 GT that made like 520 rwhp and he drove it all over the place. yes and it was a lidio car. so i don't think there is any limit as far a to fast for street. it matters on how it is tuned. Oh yeah that 9 sec 98 cobra was bad ass.......this is just my opinion. here is the article on his website.

http://www.alternativeauto.com/tuning/tuning_philosophy.html

:nice:
 
when i think street car i think balance. on the lower end of that scale(to me anyways) is 1/4 mile time. for instance what does a ferrari-insert model-do in the 1/4?

i personally feel around the 500hp level on the street one should be looking into a 3.08-3.27 rear gear. you can prolly get that to hook with a 3.73 gear, but then the ride will skewed to far in favor of a straight line run thus upsetting the balance.

this is just my take on the situation. obviously there is more to the equation such as brakes, interior comfort, ride quality. this is why i feel a badass balanced street car is perhaps the most difficult build to do.
 
Just my 2 cents...


On 15psi in 4th gear on street tires on the freeway - I can break the tires loose easily. Not terribly fun unless you just like scaring the crap out of people in the passenger seat IMO ;)

I turn it down to 10psi now just to make it 'usable' power - 493hp is what I was making @10psi as I recall. Pretty streetable IMO. I usually stay under 3200 RPM around town though. I would even go so far to say that its mild when I am not in the gas hard. Still gets good gas milage and idles nice too. 500hp is about the range where things start getting hairy on a daily driver IMHO. ;)

I personally cant imagine a driving a 700hp+ street car though. It would need 28x12.5 tires just to hook up from a roll ;)

-Jason