What is "streetable horsepower"?

SergntMac

Shelby GT X2--Back In Black
What is "streetable horsepower"? Could be anything I suppose, and I'm expecting a dozen different answers.

Second half of the question, is what is a "reasonable limit to streetable horsepower". I don't think anyone can tell the difference bewteen a 500+ HP car and a 600+ HP car without a timeslip, and both would be scary fast on the street.

I'm asking because I'm trying to sell my Kenny Brown #1x, and three times now, I taken offers from folks who want the car detuned in some way. Pull the 3500 stall torque converter out, tune it to run on lower octane gas, or, something like that. It make me think that there are lot of opinions out there, me first.

After the last build-up, everything came out perfect. Good build, good tune, and 535+ RWHP on the DynoJet. No 1/4 mile numbers yet, still working on that date. But, the car is set up very nicely, and it's quite fast.

Here's what I like about it (and not just the #1x car, but my #3 Marauder as well). It's reliable. I can go to the car, start it up, strap in and drive away without making one change to anything. No tire swaps, no add this, take that off or out, no worry about overheating, heat soaking, nothing.

One of my two Marauders always has at least a half of tank on board, and I can get 200 miles away from my garage door without stopping, day or night, rain or shine.

It's fun to have a lot of HP on the street, it's a feeling of self assuredness that you can handle any challenges. I'm surprised how often I don't show it off, because I know I have it. And, I also like the feeling of trust, that this car can (and will) get me where I want to go safely, and without any problems at all, at the drop of a hat.

Therefore, I conclude that 500 RWHP is a reasonable limit to streetable HP, and after that, reliability slowly ramps down. What say you all?
 
After the Drive and Ride in your car.... I feel it to be a good combination..... all around.

If you aren't stomping on all the time.... the car behaves like any other MM. The power makes freeway merges easier, too :D

If it comes to it Mac..... I'll trade you my car, then you won't have to sell it ;)

KillJoy
 
Mac, I think you are right on target for most of the folks and the 1x sounds like a good example. Some folks may define streetability a little differently and go for more power, but I like your definition.
 
I think that is a good number - in a fuel injected motor. Something like that with an older, carbed motor could be a little more work and not as reliable.

Shoot, you can buy 400 and 500+ HP cars off the showroom floor (Mercedes AMG's, BMW M series, Corvette Z06) and drive them like everyday cars. I think the right use of the right foot can make a reliable 500 HP car a good, streetable vehicle. And, like you said, you don't have to swap tires, run certain, race only gas, etc.
 
I want 600hp and tq for the street. My problem is $$$$$, I don't have enough to mak it happen. i could sell my old cars but that's no fun and they are not worth what they cost to build. The car hobby "catch 22". I wish I knew about your car serg. I paid 20k for my stock one. If I could work it out I would buy your car, damn kid needs to be feed and clothed though. LOL:shake: Well back to my under paid job.:rolleyes:

sorry for the rant.

ps why can't I pm you sergntMac? I want to ask about a trade. i will try to e-mail you.
 
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I think that we should first establish here the difference between REAR WHEEL Horsepower figures vs. crankshaft Horsepower. The HP figures that are published for new production cars like the 500 HP LS7 Vette are crankshaft HP, and NOT RWHP #'s. And that's a considerable difference. When I drop the 800 HP engine that I have in my Chevelle, it certainly isn't going to be puting 800 HP to the wheels. It will likely be more like 650 HP at the rear wheels. But I digress....

IMO, the first fact of life concerning an actual streetable vehicle, is that it MUST run on 93 octane pump gasoline. If the car needs a diet of race gas to any degree at all, you just took it off the street for 98% of the hotrodders out there (myself included). And that's because anyone who isn't making a six figure salary, (and even many who are) will not be able to drive very far, nor very often if they have to spend $6 or $7 per gallon for fuel. Add to that the fact that you won't find race gas at just any gas station either.

So despite how much people like to claim that their race gas engine cars are "streetable", the fact of the matter is that unless they're extremely eccentric, there's just no way that they will be driving their race gas car all that often. And for anyone to contend with that, would be like saying that they can make a funny car "streetable". Sure you can drive it on the street a few miles if you're crazy enough and rich enough to do such a thing, but because of the cost of fuel you won't be going very far, nor will you be doing that very often either.

So the first thing is that it has to run on pump gas, or forget it. The second thing is the stall speed. I can't vouch for a 3,500 RPM stall speed since I've never had a car with one that high, but I know that my car is just fine with a 3,000 RPM stall speed, and I drive it every single day even when it snows. A guy who's a member here on this board told me that he's had rides in Marauder with 3,500 RPM stall speeds, and they seemed very streetable although they weren't as "smooth" as my car is (which was a statement that he made while riding in my car).

So just because a car's power delivery might not be as "smooth" with a 3,500 RPM stall as compared to a lesser stall speed doesn't mean that it isn't a good street car. However, I haven't any doubt that running stall speeds like 4,500 RPM would NOT be very streetable at all, and it would likely heat-up the transmission so much that you would likely have to include a transmission rebuild with every engine tune-up.

Another thing is tires. Slicks would be out for the street since you can get your car impounded if a cop pulls you over and sees slicks.

Then there's camshaft lift and duration. If the duration is so extreme that there's isn't any throttle response below 4,000 RPM, then that would fall in the same catagory as a 4000+ stall speed. can you drive a car like that on the street? Yes, but how often will you really be doing that? You wouldn't be puting more than 1,000 miles per year on a car like that, and IMO, if you can't even drive your car more than several hundred to 1,000 miles per year opn the street, then you're not enjoying it too much since it cannot be used very often.

Cam lift is important too. It's been said that once you go past the .700" lift mark (any nobody here that I know of has done so with a Marauder), you'll likely end up breaking valvesprings and lifters left & right, so that wouldn't be very "streetable" unless you're only using the car to drive 10 miles to a show or a cruise night 2 or 3 times a month, which isn't my idea of a real street car if you don't use it for anything other than that. There are many cars that can be seen at cruise nights and shows that aren't very streetable at all, and are so far out on the edge that they can only be used on the street for nothing but driving to those events, as long as they're not a couple hundred miles away from where the car is kept. And that just isn't a street car. The engine I have is probably right on the edge of camshaft lift for a "streetable" car with a .705/.708" camshaft lift. The cam manufacture (Lunati) claims that the cam is "easy on valvetrain parts" so I'm hoping for the best on that.

High HP with carburetors can be tough, since carbs often require more trial & error and generally more work to get tunes right than fuel injection does, but there's a lot of guys who claim to have found custom carbs for their cars that work flawlessly, and don't have to be tinkered with at all.

So pump gas, street legal tires, stall speeds no higher than 3,500 RPM, no overheating issues, reasonable cam specs, & working headlights, wipers, and taillights would make a car "streetable" IMO.
 
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Mac, here's my .02 I think that most people are intimidated by your numbers. don't get me wrong, I like them. If people are wanting to de-tune the motor, they feel it is too much for them, and perhaps they should be looking else where. If I were looking for a new ride, I would be a little leary of a modified ride with lots of HP. Who did it? Do they know what they were doing? And how would I know that? Has the car been driven spiritedly often? Since your is a KB that should diminish some of that concern. Let's face it, the ride does change when mods are done.. Better or worse depends on what you like. She will sell no doubt. This is not a average ride you have and someone who appreciates will be found. Good luck.
 
I'm running 570rwhp and I feel no more need in the stang. The 275's on the back are useless untill the top of 3rd gear, otherwise I just spin. If I ran drag radials I could hook up in some of 2nd but I drive the stang alot and it wouldn't be worth it. Runs good, has been very reliable, full A/C. Drove it to and from Steamboat Springs, CO a few months ago for a car show/auto-x. 400 miles each way. Didn't skip a beat.

Edit: and she runs on 91 octane. :)
 
IMO, drag radials are a MUST on any car with 400+ RWHP. Otherwise, you're just wasting a lot of HP. I run DR's on my daily driven S/Ced Marauder 8 months out of the year. They don't last long, but that and less than superb gas mileage is the price you pay for having a real fast car, and one that can blow the doors off of any other car that you'll encounter during your daily commute to work and back. ;)
 
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Mac, you afforded me the lucky opportunity to drive your #1x car for a short time the other day and I thought it was thoroughly "streetable". Maybe it might be considered a little loud at the exhaust end under wot by some bystanders ( but not the vehicle occupants), but I thought it drove just fine and sounded great.:D
 
AMEN, Brother! Thank you for confiming my views.
BillyGman said:
IMO, drag radials are a MUST on any car with 400+ RWHP. Otherwise, you're just wasting a lot of HP. I run DR's on my daily driven S/Ced Marauder 8 months out of the year. They don't last long, but that and less than superb gas mileage is the price you pay for having a real fast car, and one that can blow the doors off of any other car that you'll encounter during your daily commute to work and back. ;)
 
SergntMac said:
I'm asking because I'm trying to sell my Kenny Brown #1x, and three times now, I taken offers from folks who want the car detuned in some way. Pull the 3500 stall torque converter out, tune it to run on lower octane gas, or, something like that. It make me think that there are lot of opinions out there, me first.

I would ignore their excuses, they are not % in the car, just joy riding. I had a 914 that I set up for auto cross and a built motor. I heard the same thing, until a younger sports car nut came along and bought, didn't even haggle over the price.

I would take would be buyers on a test drive and scare the blank out of them.
After I took the sports car nut for the test ride he could not wait to buy her.

5 years latter she was parked in front of my house still in excellent shape!

If you can legally drive it in the rain then the HP it has is streetable.
 
sailsmen said:
If you can legally drive it in the rain then the HP it has is streetable.


This is exactly why I don't run drag radials on my stang. It gets driven in the rain frequently.
 
Nitrous SSC said:
This is exactly why I don't run drag radials on my stang. It gets driven in the rain frequently.
My car gets driven in the rain every time that it rains since it's the only car I have on the street, and has been for the past two years, and the drg radials are fine as long I don't get into the boost, and I take it easy around turns. you definateky have to be mindful, and easier on the throttle in the rain with drag radials, but you should be taking it easy in the rain anyway. 60 MPH on the highway even during a downpour is no problem with DR's.
 
Thank you all gents for some thoughtful replies. I'm not so much concerned about my MM, as I am about the general topic at large. Is there such a thing as too much power, and where is that line drawn when defining "streetable". Special thanks to Billy G for a well prepared and thoughtful post.

Fairlane347 said:
ps why can't I pm you sergntMac? I want to ask about a trade. i will try to e-mail you.
I don't PM, because it's not really private. It can be read by administrators. But, I did get your e-mail and replied to that a few moments ago.

Thanks again gents, carry on.<!-- / message --><!-- sig -->
 
BillyGman said:
IMO, drag radials are a MUST on any car with 400+ RWHP. Otherwise, you're just wasting a lot of HP. I run DR's on my daily driven S/Ced Marauder 8 months out of the year. They don't last long, but that and less than superb gas mileage is the price you pay for having a real fast car, and one that can blow the doors off of any other car that you'll encounter during your daily commute to work and back. ;)

I wouldn't agree, I drive on the stock tires just fine;)
 
RR|Suki said:
I wouldn't agree, I drive on the stock tires just fine;)
To each his own. As long as you enjoy your car. That's what counts. As for me, the way that I look at it, with RWD cars that have some good low-end torque, there's no way that you're gonna hook-up completely from a standstill off the line at full throttle on the street no matter what tires you have. But the closer I can come to that, the better. What I mean is that the more throttle I can use from a standing start w/out spinning the rear meats, the better. And with drag radials you can give it more gas off the line as well as from a 15 MPH roll and still get perfect traction than you can with standard radials.

I can also hit full throttle from a 30 MPH roll and get a 100% traction with 4.56 gears in the rear and drag radials. I can't do that with standard radial tires. In fact, with the stock tires, I couldn't even get into the boost at all with my car in first gear w/out spinning them.
 
Two examples I can think of off the top of my head. Kid up the street has a evry fast '69 Camaro. Built 502 Merlin, big cam, carb, etc. He runs it around town on Saturdays. Sounds good, will light the tires at will, runs DR's. Biggest problem is that he must re-tune it weekly to keep it right. It's streetable sure, but most folks don't want that much work. Example 2. Another guy in the 'hood has an '03 Cobra. S/C (with a smaller pulley), milder cams (but still with a little "lope"), exhaust, etc. He May not run with the Camaro, but he probably wouldn't be more than a door away at the trap in a 1/4. This car is driven every day, hood stays closed, and is about as much fun as example 2. He can sit in traffic with the a/c on, hear the radio, and ride in the rain. Just 2 cars with close to the same hp, just set up a little different. Streetable hp is more how you are set up than an actual number, IMHO. From what I've heard, Mac's 535rwhp would fall into the streetable category.
 
I think "streetable" can be broken down into the objective and subjective categories.

Objectively its easy to define. To be "streetable" means being street legal. That means no slicks, working lights, wipers, and all the other legal equipment requirements.

Subjectively is where things get tougher to define. This is where power levels, tuning needs, weather conditions, and other variables come into play. Accordingly, "streetable" is defined by each person and their own comfort levels.

Power level is hard to define as streetable or not without assessing how the rest of the car is set up. A car with 650rwhp that is set up right can be more reliable and controllable on the street than a 400rwhp car that is set up poorly.

As for race gas and all that....I say who cares. Here in Detroit race gas is easy to find. I wouldn't be surprised to find that at least 1/4 to 1/3 of the cars cruisin woodward on summer nights are running race gas. many of these cars are set up well, run strong, are street legal, and are reliable. To me, that's "streetable" regardless of the gas the owner decides to pump in.

On the other hand, I've seen 300hp cars running on pump gas that were not streetable. These guys are running insane boost (with crappy pump gas octane on the verge of grenading), bad tires, and suspension that allows the car to walk sideways down the steet. That's simply not streetable.

In a nutshell "streetable" to me is: street legal, reliable enough to take a road trip or get stuck in traffic on a hot day, and is set up with power levels and supporting suspension and drivetrain to allow for safe operation on the street with spirited driving. It also means that the cars performance range can be taken advantage of on the street and does not require track use to feel the full potential.
 
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IMHO.....Streetability = Driveability + Safety!!!:banana:

My Cobra with 500+CSHP (I had a "Testosterone Moment") borders on Non-streetable??:mad: The cam I have is good from 1800 RPM's to 6500 RPM's and is fairly awkward in trafic as the idle is "Lumpy" and low speeds are fairly rough....on a daily basis!!:rolleyes: Above 2000 RPM's it is as smooth as you wish and really fun.......BUT....then you have traction issues to deal with!!:eek:

In cool air it will spin a lot in 2nd and a bit in 3rd at WOT......Not for everyone on the "street"!!:confused:

My Marauder is dangerous in the rain....as you might expect...and I RESPECT IT!!;)

The "Average Guy" will be "Non-Streeetable" in what we consider "Streetable"....so I think it really boils down to experience and respect...unless you have a really wild engine combo that rivals the NASCAR boys!!:bows:

My $0.02....fer what it's worth!!:confused:

Marauderjack:burnout:
 
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