with all the talk of 1000+ hp street monsters around here a few people have stopped to ask "how much can you really use?" (myself included)

just wanna explore it a little more here, like how much can you put down with what tires and what cars, and in what conditions
i've heard a lot of people reply with the answer that the most you ever want on the street is about 600hp, that thats what will probably give you the most enjoyment even in a all-out street monster


i posed this question in another thread but never really got an answer: how much can each of these tires let you put down (eg. eventually be able to put the pedal to the floor), i think each is about the best in its own arena of streetability/traction

295 BFG kd's or 345 michelin pilot sports (the dry traction streeters)
315 nittos (the street drag radials)
315 BFG drags - or the newer version in 345 (the track drag radial)
ET streets (the track street tire??)

assuming the car has associated suspension mods for street/strip of course
and how much does the car itself come into it? how much can a 4th gen f-bod put down versus a c5 vette with similar level of modification and tires? 1st gen f-bod? viper?

and of course the difference in weight between a c5 vette and 1st gen f-bod is somewhat substantial, so how much does that come into it? obviously a heavier car will be able to put down some more horses, but will not be able to accelerate as fast

i found this article really interesting which is related
http://www.hotrod.com/techarticles/42798/
down toward the bottom it talks about how many g's a car can pull before breaking the tires loose
so now my question is, what cars and tires can pull the most g's before breaking them lose?

the article mentions fwd cars which are of course the worst and pull 0.4-0.5, then a number of rwd cars with skinny (215mm) street tires that pull in the mid .5x range, and 4th gen f-bods that do over .6
the thing is though the difference between a pickup truck and a sports car isnt huge, but a truck may only be able to put you in your seat from 0-30 while a vette can also do it from 60-90
he mentions an nsx on race tires that consistently did .75, but unfortunately doesnt mention anything about any muscle cars with slicks/d-r's
he sort of makes the conclusion that wider tires dont really increase this g-pulling ability, they are just for show
is this true?
also i am interested in this g-pulling figure because even my old beat up jeep pulls awesom in 1st, and my t/a breaks the tires in first with its current (bald) tires, but it also pulls in 3rd and 4th

i'm actually a bolt-on guy myself but i find this all real interesting
i didnt really buy my car for track times but to just pin me to my seat on green lights, i think 4.10 gears and nittos for my trans am will go a long way in making me happy

i put up a lot of questions but just sorta wanna open the discussion on the topics
how much you can put down
what tires/cars can put down more
and is pulling g's without breaking the tires a better measure than "putting down" power?

 

bump
back from the dead

thought this would be an interesting discussion, no takers?

 

Did you see the video of the 9 sec turbo C5? The front end was very high the whole way.






a 4th gen f-bod put down versus a c5 vette with similar level of d of course the difference in weight between a c5 vette and 1st gen f-bod is somewhat substantial, so how much does that come into it? obviously a heavier car will be able to put down some more horses, but will not be able to accelerate as fast


down toward the bottom it talks about how many g's a car can pull before breaking the tires loose
so now my question is, what cars and tires can pull the most g's before breaking them lose?

how much you can put down
what tires/cars can put down more
and is pulling g's without breaking the tires a better measure than "putting down" power?

I think it is all about weight transfer, a higher powered car with the same set-up can transfer weight more.

 

This has been dicussed pretty extensively before, there are a variety of opinions. Some disjointed thoughts of mine on the subject.

1. One thing to keep in mind is that every car has a built in traction control system, which is usually called a "driver".
2. Traction differs widely under different conditions.
3. Tires are obviously a big part of the equation. Tires with very high coefficients of friction are desirable for traction, but will tend to wear very quicly and may have other undesrieable characteristics, for example, while I know people do it, driving on the street with ET "Streets" except for very short distances under perfect conditions in a powerful car is, at best, "unwise". (I don't want to say "stupid" and get some of you angry).
4. Weight distrubution plays a big role in determining maximum tractive effort, as does overall weight (as someone already mentioned).
5. The torque curve and how the car responds to the throttle can play a big role in determing the ability to control very large amounts of horsepower.
6. Even a stock LT1/LS1 can easily break the tiress loose in first gear (except maybe an A4 with 2.73's). Does that make it too powerful?

All that taken into account, I think the 600-800rwhp range is in the ballpark for an F-body. Last year, the setup for my heavy (near 4,000lb) convertible was ~600rwhp on blower and ~750rwhp on nitrous. On blower, it was pretty usable though you had to be judicious with the throttle in first and second. With the N2O, it would break the tires loose in 4th (at ~90mph) when the nitrous hit. A large part of this may have been the sudden "hit" from the nitrous though. Which is an illustration of #5.

Next year, I will have an automatic, more hp, and better tires. All of which will effect the amount of power which can be put down effectively. If I decide to use the N2O on the street, I will probably use some sort of a staged setup or nitrous controller.

Anyway, you are going to get different answers from different people, unless they are already talked out on this subject.

Rich Krause

 

It’s not really about the coefficient of friction, after all we get a lot more ‘stick’ out of tires then you could ever predict using rubber-asphalt’s coefficient of static or dynamic friction. It’s about how well the rubber deforms and grabs the voids/texture of the surface you’re on. This is also why stickier tires usually wear faster, because if the rubber is in one of the road surface imperfections it’s much easier to tear it off the tire, so the better the compound ‘grips’ the surface the more it will wear.

hum… Ever get caught in the rain with some of the wider bfg drag radials? With any treadwear even they’re undriveable over about 35mph. As are most DOT slicks. I’ve found 2 tires that work really well in ‘weather’ that are also pretty good at the track: Nitto drags (I swear that they’re better in the rain then some all season tires, as long as there’s no standing water) and McCreary dirt track tires (sticky, handle well, well if you can get used to the bias ply funkiness, even work OK in snow, the problem with them is that without an inner tube they’ll drop to 5psi in a day…)

Otherwise I totally agree with you, especially the part about what is driveable and safe on the street is really up to the driver (and partially up to your tuning, if the car wants to leap from idle to 4K as soon as you touch the gas 300hp could be a handlful).

 

i wouldnt think so because a front wheel drive or AWD can pull more g's than us cant they? but we can definitely put more power down and g's is all a matter of suspension and tire grip while power is as well tire grip but in a straight line kinda way. with the right suspension/tires, a 91 ford escort hatchback could pull as much as a z06 even though the escort would have nowhere near the same hp and tq numbers or curve

 

an fwd will never put you on your seat as hard as a rwd setup..... and as far as i understand it, awd really has the benefit in street tire vs street tire

as soon as the rwd car is in a situation to lift or almost lift the front wheels (good suspension and sticky tires) then it will beat the awd
you guys seen the video of that 1000hp skyline off the line? it definitely does a wheelie, dont see how awd is helping it there

 

you may be thinking of turning g's (even then your statement is debatable)... we're talking about straight line g's... the oomph that pushes you back in your seat when you nail the gas.

 

AWDs can sometime pull over 1G but just for a couple of feet since the 1-2 shift comes up so fast and decreases the mechanical advantage (and hence force present at the tires). This is the gotcha with gearing, you can gear up to have the same amount of force (and accel) but the amount of time you can produce it diminishes. This is the good ole HP vs Torque argument in fact. Gearing can make up for a torque difference but hp 'basically' tells you how long you can take advantage of the gearing.

The rearward weight shift of a FWD under accel will kill its realized forward accel because it unloads the front tires


Keep in mind, in order to achieve the accel of 1G, the propelling force at the tires has to equal the weight of the car.

A sticky tire will have the equivalent of a 1.6-1.7 coeff. of friction. With the 60-40 weight distribution common on fbody will allow one g or greater depending on the ability to shift the weight to the rear tires.

That said, on a a city street the dirt and other contamination will limit the real grip you can get. For instance, the best I get is .946Gs with my 96Z/DRs and a solid rear suspension. This is at 30ft or so due to spinning out due to only being able to modulate the pedal so much with 4200RPM stall and boost.


HTHs,

-CAL

 

If your 60' time is 1.5sec, that's an average of 1.67g, that's why it feels so good . There are folks in the low 1.3's with a 10" tire stock suspended car, that's 2.2g's

Rich Krause

 

Avgs are not really that high This is due to the staging depth and the fact the car crosses the first light doing about 7.5mph-11mph in these respective cases.

Peaks of 2.7Gs can be had in the case of a 1.3 case. Well that is what a buddy of mine said he got in his baby blue tubbed pinto running 5flat in the 1/8th. (scary runs at that given the short wheelbase)


Umm you shouldn't be having a problem pulling a 1.3-1.4. So Rich toss a Vericom/Gtech in there and let us know My last run was a 2.4 60ft and I went thru 3 on/off the throttle cycles at that


-CAL

 

What formula did you use to calculate "gs" based on the 60' time? I went 1.09 on a pretty mild launch testing the dragster last week.

 

I just used the calculator at www.prestage.com, the results seemed in the ballpark. My friends alcohol Hemi altered has a 60' a bit less than 1sec, the calculator gives 4.13g's for a 0.95sec 60'.

Rich Krause

 

That calc is way off. For example, it says my stock 02 lightning has an Average of .93Gs wit a 2flat 60ft. I only wish. It registers a true .76Gs max and around .45-.4Gs at the 60ft. A better way of looking at it is, do you really think my L can hit 40mph in 2 seconds like the cals says?



Here is an example of a a Z28,3600Stall,2.73 and GSCs calculated with MY software and validated with a vericom. IT had 370RWHP at the time. Notice the distance 0 has a speed of 7.5mph. You have to add about 3ths to the time to give a 0-60MPH since that is how long it takes to move that short distance and get to 7.5mph. The best with this cars setup (it had a NOS5176 kit at the time) also gave a REAL 0-60MPH time of 4.12sec. Not to far off from my calculated is it



(the > than after Gs is my representation that wheelspin is occuring and not limited by power, just traction)

Speed Time G's Dist HPKP
7.5 mph 0.0 seconds >0.770 0 15.40 3600 rpms
20.0 mph 0.7 seconds >0.768 14 40.97 3600 rpms
30.0 mph 1.3 seconds >0.766 36 61.25 3600 rpms
40.0 mph 1.9 seconds 0.716 68 76.42 4406 rpms
50.0 mph 2.6 seconds 0.646 112 86.07 5508 rpms
50.5 mph 2.7 seconds 0.645 114 86.80 5563 rpms
60.0 mph 3.7 seconds 0.465 197 74.41 3600 rpms
60.5 mph 3.7 seconds 0.449 201 72.50 3600 rpms


Lotsa clipping... but notice the avg Gforce was around .75Gs (1.7 60ft) and this is a 370RWHP setup, not a 2 second 60ft like show above for the lightning. Add the 2-3ths ( I have the actual formula to determine the rollout speed if needed) to the other calculator and then you are back in the ballpark. The fixed 2.3sec 60ft would equate to an average of .7Gs average for the L.

 

Guess you could probably ask this guy...


Anyway, I have a relevent question on this subject. What is the shortest "short time" known. Anyone know, and what kind of vehicle pulled it?