How Fast Is A SL-C?

[Cody DeHart]

My car has the LS7 stroked to 441cc with Richardo transaxle.

Today I got the opportunity to race a 2016 McLaren P1 and a Porsche 918, we did three different pulls, from 30mph, from 45 mph and from 60 mph. The results were the same every time. The SL-C pulled out from the cars and by the end of the run I had two car lengths on the 918 and about 6 car lengths on the P1. So people ask me all the time how fast is it, now I have a frame of reference


What cars have you guys played around with in your SL-C?

 

[Mike]

Did the P1 know it was a race?

 

[Les]

When you say "fast", do you mean
1. how quickly can you accelerate to x miles per hour?
2. what is your SL-C's top speed?
3. how quickly can your SL-C cover x distance (a quarter mile, a lap of a particular race course, laps over x time {1 hour, 24 hours})?

 

[Justin]

Those had to be some pretty short races. Doesn't the P1 and 918 do 30 to 60 in a second? How would you be able to tell how much faster you pulled away from one or another in just one second? Besides, 0-60 is almost meaningless to "super" cars now. What really matters, is how fast "said" car can do a lap at a proper race track. (Drag racing is stupid. Any dipstick can press the go pedal and knock down an 8 second quarter if you've got enough money.)

 

[Howard Jones]

Don't street race....you'll end up rapped around a tree, dead, and on fire.

 

[Keith]

Clearly you must be running close to 1,000hp with traction control?

 

[James]

If you think about it, acceleration is just a factor of power to weight and traction.

Yes, things like gearing, power delivery, weight distribution, and aerodynamic drag (for the higher speeds) all have factors, but it really comes down to, how much do you weigh, and how much power are you putting down.

I could very easily build a Mustang/Camaro that would walk over a 918 or P1, but it won't handle, turn or brake as well as the 918 or P1 does. Don't get me wrong, it was nice to see it out accelerate them.

I agree with Justin. I would love to see what the SLC does against the top echelon cars on the track. All with street tires. I would love for the SLC to smack down the others just a much as anyone else, as I'm in the middle of building one.

 

[Keith]

Yes it would be interesting and I think a fair test would be if the Supercars defeated all their sophisticated electronics for the test, otherwise it would be difficult to complete head to head unless you spent some real cash...

As you say, weight is an extremely important consideration here....

 

[James]

Yes it would be interesting and I think a fair test would be if the Supercars defeated all their sophisticated electronics for the test, otherwise it would be difficult to complete head to head unless you spent some real cash...

As you say, weight is an extremely important consideration here....

Actually, I think it would be more fair if the cars kept their sophisticated electronics. Most supercars today get that extra 1/10th for that very reason. It's not only physics you are trying to exploit, but how much of those physics you can use.

For example, the Nissan GTR is an incredible piece of machinery. It's still blows my mind that the car can do 0-60 in 3 flat with 520hp having to pull over 3800lbs, and for such a heavy car, it remains very agile. It did The Ring in 7:19.

If you think about it, a highly modified Toyota Supra with over 600hp, (and weighs about 400-500 lbs less) did it in 7:49 over a decade ago. I bet if it had all the electronic assists the Nissan had, it would be almost as quick.

If you have a light car, a low center of gravity, lots of power and a good suspension set up you will inevitably have a fast car. The rest of it, is using that power. The Nissan, and the 918 (and probably the rest) are so good because allows the driver to user every bit of potential the car has.

 

[Mike]

I could very easily build a Mustang/Camaro that would walk over a 918 or P1, but it won't handle, turn or brake as well as the 918 or P1 does

Describe the build. Probably would have a turbo and would be running race gas maybe E85. Even then it would take a pretty nasty build to run down a P1 even in a straight line. I'm sorry but I'm not seeing an LS7 SLC putting lengths on a P1 or 918. They are going to jump it out of the hole and then just walk away.

 

[Keith]

I'm with Mike on this one. But I guess the video will prove/disprove it?

Put the video up Cody: It would make a huge change from Cars & Coffee (sorry Mike)..

I don't know about anyone else, but I'd love to see it...:thumbsup:

 

[James]

Describe the build. Probably would have a turbo and would be running race gas maybe E85. Even then it would take a pretty nasty build to run down a P1 even in a straight line. I'm sorry but I'm not seeing an LS7 SLC putting lengths on a P1 or 918. They are going to jump it out of the hole and then just walk away.

I'll be a bit generic, as there are obvious supporting mods that you would need to make in order for this to happen. Take say a late 90's Camaro, Bore x stroke it out to 6.8L (would require sleeving and replace the stock LS1 heads). Add a couple of turbos. You are at a very easy, and actually very streetable 1100 - 1200 HP. Strip the car down. Now you are at around 2700lbs. Put on some D.O.T street tires and a nice traction control unit.

Not saying it would be comfortable, quiet driving car, but it would be "in a straight line" as fast as the P1.


Cody's 441 LS7, would have at LEAST 600HP, and is probably closer to 700

P1 weighs in at 3280 and has 908HP giving it a
Power to weight ratio = 3.6lbs/HP

Cody's SLC probably weighs around 2400lbs and lets say 650hp
Power to weight ratio = 3.7lbs/HP

I say it's pretty close. Also, remember, the P1 has a 3.8L engine with two turbos, so it's trying to get 727HP out of a 3.8L or 191HP/Liter. The trade off is a little bit of turbo lag. Granted, turbos have come a long way since the 80s, and there isn't near the lag there was. However, I will say this.

Everything being equal and you have two identical cars with the only difference being one is turbo, the other is NA. The NA will be faster, as it does not have to worry about transient response and lag. Whereas you step on a turboed car, you have to wait for the exhaust gases to build up enough to push the turbine, which in turn pushes the compressor to bring in air.

 

[Eric in Florida]

I believe it, but take it to the strip on open to the public nights, run the quarter post the time. Next time someone asks pull out the ETA slip. Only things Americans know is 1/4 mile times, magazines use that with new car tests.

 

[Eric McClellan]

I think I'd let the Stig decide.

 

[Ron R.]

Cody?

"You have some "spainin" to do"

 

[Keith]

I'll be a bit generic, as there are obvious supporting mods that you would need to make in order for this to happen. Take say a late 90's Camaro, Bore x stroke it out to 6.8L (would require sleeving and replace the stock LS1 heads). Add a couple of turbos. You are at a very easy, and actually very streetable 1100 - 1200 HP. Strip the car down. Now you are at around 2700lbs. Put on some D.O.T street tires and a nice traction control unit.

Not saying it would be comfortable, quiet driving car, but it would be "in a straight line" as fast as the P1.


Cody's 441 LS7, would have at LEAST 600HP, and is probably closer to 700

P1 weighs in at 3280 and has 908HP giving it a
Power to weight ratio = 3.6lbs/HP

Cody's SLC probably weighs around 2400lbs and lets say 650hp
Power to weight ratio = 3.7lbs/HP

I say it's pretty close. Also, remember, the P1 has a 3.8L engine with two turbos, so it's trying to get 727HP out of a 3.8L or 191HP/Liter. The trade off is a little bit of turbo lag. Granted, turbos have come a long way since the 80s, and there isn't near the lag there was. However, I will say this.

Everything being equal and you have two identical cars with the only difference being one is turbo, the other is NA. The NA will be faster, as it does not have to worry about transient response and lag. Whereas you step on a turboed car, you have to wait for the exhaust gases to build up enough to push the turbine, which in turn pushes the compressor to bring in air.

The hybrid keeps the turbo spooled. With these cars, lag is a thing of the past..

 

[James]

The hybrid keeps the turbo spooled. With these cars, lag is a thing of the past..

Hybrid doesn't do a thing for the turbo. It acts as motor to provide an extra 170 hp to drive the wheels.

Now.... if it electrically spun the turbo,, then that's a different story,, but it doesn't.

 

[Keith]

Hybrid doesn't do a thing for the turbo. It acts as motor to provide an extra 170 hp to drive the wheels.

Now.... if it electrically spun the turbo,, then that's a different story,, but it doesn't.

From the tech spec. "Although not technically "spooling" the turbo, (you are quite correct), it does eliminate lag by virtue of the electric motor which can be deployed manually by the driver or left in automatic mode, whereby the car's ECUs 'torque fill' the gaps in the petrol motor's output, which is considered turbo lag. This gives the powertrain an effective powerband of almost 7000rpm."


176hp and 191 lb-ft of torque is the EM output..

 

[Mike]

Hybrid doesn't do a thing for the turbo. It acts as motor to provide an extra 170 hp to drive the wheels.

Now.... if it electrically spun the turbo,, then that's a different story,, but it doesn't.

They actually inject fuel into the exhaust stream to keep the turbos spinning I believe. Comparing Mclaren technology to what Joe Blow can build in his garage is really not fair. A P1 would walk a 700hp SLC like Slick Willy leaving the Bunny Ranch.

 

[Keith]

But but the OP says he already blew a P1 and a 918 away Mike! Just waiting for the videos...