You're right...it's that dillweed Dep ;)
:lol: :lol: :lol: :lol: :lol:

 

Dont worry bout him... he's all horsepower and no torque... :p:

 

Since the original poster asked about a drag race, we have to think about 1/4 mile racing, not street races, NASCAR or IndyCar. The first thing you have to do is find that series of drag race calculations and predict 1/4 mile speed using estimated HP. Then pick a cam that gets you that amount of HP. Then pick rear gears that get you a couple hundred rpm over the hp peak rpm at the finish line. Then calculate the maximum 1st gear ratio for the tire size you have. Then you have to change the rear gear because you have limited choices of 1st gears. That changes your rpm at the finish line. So you have to change cams. That changes your HP and trap speed. So you start over. But hopfully after a few iterations you get everything right. Have fun! Joe

 

OR

You build your motor based on what the factory has already researched and developed. You eliminate an expensive trial and error routine, and off you go winning races :)

Dep

 

Someone finally got it right :thumbs:

 

But what if you want to be quicker than stock? Let's face it, the winners win by making their cars faster than the factory did :).

 

The winners have an unlimited budget and get a large portion of their parts for free. If you build a big block to stock LS-7 specs you are gonna pretty much trounce most of the competition. Most guys on here buy all kinds of expensive aftermarket doodads that cost ten times what the stock parts that do a BETTER job cost. But then...they get to write that nice long laundry list in their signature ;)
The STOCK L-88 made well over 550 HP. I'd be surprised if many people on this forum come close to that number, even with all the aftermarket doodads they install.

Dep



[Modified by Dep, 10:48 PM 11/25/2003]

 

Well I do. I don't talk much about it. But I recreated a "modern version" of an L88 just to see if I could, and to see what all the fuss was about. Man, that engine does have the top end mojo, no doubt about that. It sacrifices torque below 3500 in favor of major power up to 7200, but it's not a stone either. It can lug at city street speeds without any trouble, but obviously it prefers to be travelling at over 3 times whatever the speed limit is.

The motor is a little hard to live with on the street, but open it up, and it brings on a major smile. With today's technology, the cams, the intakes, the fantastic carbs, and heads, it's really not hard to improve upon the L88. Just expensive. But it's only money, right?

Look at it this way Dep, I didn't give up my torque, I just moved it way up the rpm band. As a result, my ultimate horsepower numbers are kind of high. I do plan on dropping my theoretical top speed from 175 down to more like 155 with a set of 3.70 gears though. Might make street-driving a little friendlier...albiet wilder.
:rofl:

 

Man, can you imagine how much I hate to do this, but I agree with Dep :D You really can't go too far a field if you go with a proven factory package. I'm not saying that there aren't guys who make more power with their own combos, but an engine that makes a broad power band with a very high degree of reliability is what the factory really excelled at, and at a very reasonable price. Fancy, shiny, and expensive go fast parts often promise more power than they deliver when compared to the factory parts.

Building a fancy high tech motor with all the latest parts is fun, but the potential benefits over the straight forward factory version is not as much as many people think.

Chuck

 

But then again...don't count me on the horsepower side of the war either. I do love torque. I've got two cars that make a bunch of torque, and both are super fun to drive.

The Firebird is all about torque. With its built, high compression 455, it's really an animal. This thing for some reason only has 3.08 gears, but you'd never know it. 600 lb-ft makes 3.08 gears feel pretty good! A lot like a lesser engine with 4.56 gears. However, above 5600 rpm, you'd better have another gear to grab. I once absolutely punished a C5 getting on the highway, but once I was in top gear, I was in trouble. This car loves life a quarter mile at a time. (And don't worry, better gears are in the plans).

The IROC Camaro I drive to work is a bunch of fun. I simply took my old Vette 10:1 engine and slapped the ported TPI on it. I didn't even change the California-spec 305 prom. (I tried, but someone on this forum never came through on his prom deal for me). A little dual exhaust custom work, and that IROC will keep up with an LT1 C4 Corvette and the hot new Subaru WRX. It shouldn't with that prom and no power above 5400, but it does.

So don't line up next to a 455-SD Trans Am and think your horsepower has his torque covered, because you could be in for a big surprise.

 

Bearcat, have you gone up the street to Bandimere's with your updated L88 yet? Just curious what it would do there in Morrison. And when you do run, do they give you a correction factor for your time because of the altitude?

Chuck

 

It's probably too late in the thread for this,but anyway,the real poiint of looking at torque is not to see exactly what the max is.....what really matters is where in the rev band it is made,how "flat" or progressive it is and most importantly how long the gearing will enable you to keep the vehicle reving in the optimal part of the band....in simple terms,because it is a calculation,300rwtq at 6000 rpm is a higher figure for hp than 300rwtq at 4000 rpm...john :chevy

 

Wes, I could help you answer your question if you had a Sharkport 2 (accessory to the PS2). I build hybrids in GT3 (and GT2, but that's with a different tool). I can take any part off any car (except paint and stock wheels) and slap it on a different one. I could build two ZO6s with the same HP, same gearing, same tires, etc. but have completely different TQ specs. We could even build you a ZO6 that's twin turboed to help you make up your mind :chevy :thumbs:

Going back to the HP vs. TQ thing... this is why I love to carve canyons in the asphalt. There's nothing like coming up on a corner, pressing half of my foot on the brake pedal to activate the binders, blip the throttle with the other half and downshift a gear or two, turn in, feel some lateral forces on my body, carve the apex, smash the throttle, feel the small of my back get pushed hard into my seat (read: TORQUE + gearing) and fly out of the corner with the tires barely crowning the pavement :smash: :seeya


[Modified by 1969Vette350, 6:39 PM 11/26/2003]

 

Thought of some more things in these wee early hours. We, as Americans, generally drive stoplight to stoplight. What does this require? Good old V-8 torque baby :boxing It's the grunt down low that shoves you in your seat. I love to fly, and you can feel the same forces except you have a third dimension to play around more freely in. Yaw and pitch aren't bad in a car, so long as the road is "yawing" or "pitching" with you; it's when you get into a roll or pitch situation when the road isn't going the way you want it to that you get into trouble.

Torque beats the crap out of those 4 banger ricers that are all show and no go and don't make enough torque to tighten my nuts.... er, I mean, lug nuts.

Other countries depend on horsepower (or as they call them, kilowatts) because there are long stretches of road with no speed limits and accelerating from 90 kph to 150+ kph is regular for them. That would be the Autobahn I'm referring to :D Their cars do need to favor horsepower because that's where the revs are going to be living a lot of the time.

Think about this for a second- doesn't a Ferrari F355 look kinda funny sitting on a dragstrip? What about a 1970 Chevelle SS LS6? One of these things isn't "at home" on the dragstrip, it needs corners, long straightaways and lives in the upper RPM band. The other *hint hint* the Chevelle, suffers horrible aerodynamic drag (relative to the Ferrari F355) and would really prefer you drive it hard a quarter mile at a time, as in stoplight wars.

I'm a big fan of torque because that's what I grew up around and that's what is the most applicable here. When the light turns green I smash the throttle and I want instantaneous oomph. If I grew up in Europe and my dad had a Ferrari 328 GTB in the garage when I was a kid, I'd probably laugh at the silly Americans who waste gas going nowhere fast. Stoplight wars? What are those? Speed limit? Okay sure, it's called "Reasonable & Customary" though.

Put me in the category as wanting more torque than horsepower, but give me plenty of both, say 500 TQ and 450 HP naturally aspirated.


[Modified by 1969Vette350, 1:24 AM 11/27/2003]

 

1969Vette350: all well and good IF you are driving your Vette on the street.
I drive my '98 on the street, my '72 is for strip-only, and I don't pay ANY attention to dillweeds in *** kamikaze bombs with mufflers the size of a jet exhaust. For the life of me I can't understand why Vette owners get all riled up and feel the pressing need to mess with these ding-a-lings. ESPECIALLY on the STREET. If you wanna race them...go on the strip. But be warned...they are VERY fast and they spend a LOT more $$$$ than you ever will to go fast. Be prepared to lose often. Their power-to-weight ratio is awesome!

"Think about this for a second-doesn't a Ferrari F355 look kinda funny sitting on a dragstrip?"

It sure doesn't look funny if you're the guy next to it and has to race it!
A Chevelle and a Ferrari would ONLY meet on the strip in a grudge race.
So you think drag cars DON'T live in the upper RPM bands???? :confused: :confused:

You are comparing apples and oranges with Ferrari and Chevelle . I notice you completely ignore the NASCAR cars that race on road courses. They do surprisingly well for big elephants on twisty tracks.

NEVER try to pidgeonhole every vehicle into one catagory. The Vette isn't ONLY for sports car racing. It can do quite well at the dragstrip with the right drivetrain combination. The Shelby AC Cobra was VERY effective on the dragstrip as well as being a Vette-killer at the sports car tracks. Even my beloved Cheetah came in a drag race version, although it was originally designed for sports car racing. Being a sports car does NOT exclude you from turing in VERY respectable 1/4 mile times.

I don't know what part of the country you grew up in...but here in the Midwest we couldn't even SPELL torque (Edelbrock spells it Tork...which is what I prefer). HORSEPOWER was and IS king. Tork didn't rear it's ridiculous head until the government legislated away big engines with lots of horsepower. Since tork numbers remained higher than horsepower, low-horse engine owners "discovered" tork and started quoting those higher numbers. Heck, even Chevy did it! They don't quote horsepower AT ALL on the dash plaque on my '72 454. But they got that massive tork reading there plain as day.
Tork remains important for trucks and off road vehicles. But even American cars are switching back to horsepower claims and not tork as the measuring stick of performance. People can relate to HORSE power...even if they don't know the technical explaination of what it means. Tell someone you have 375 horses for power and they say "WOW"!!! Tell them you have 600 foot pounds of tork, and you'll likely hear "yeah...but how much HORSEPOWER do you have?" :D

Dep



[Modified by Dep, 9:50 AM 11/27/2003]

 

Here is a graph showing a 300-HP, 400-HP and a 550-HP setup. Discuss.

 

Yes, yes I do drive my Vette on the street. I don't go to a racetrack, and when I do, I'll take it to a road course.

My friend, in his 5200-pound truck, took a C5 off the line. The Corvette messed him up when he (my friend) ran out of gears to grab. I would speculate it was because the Corvette driver wasn't expecting something that pushes more air than a barn door, but the idea that I'm basically building a version of his engine to go into my car, something that weighs about 2100 pounds lighter, is freakin' awesome! He says it makes around 400 ft. lbs. of torque and about 350 horsepower. Not too shabby for picking "cheap and reliable" (Cheap/Fast/Reliable - pick any 2 of the 3.)

I'm planning on building a fuel injected 427 stroker out of a modern small block LS1/LS6 for my '69 as the long-term project; check my sig. Those little ricers can be faster than stock, but unless they're: A) injecting nitrous B) boosted to the brink of blowing their motors or C) are a purpose built racecar, they are generally running in the 13-second range, plus or minus, something even a small block V-8 can attain pretty easily. I always wondered why these guys bought a Prelude or Civic to start out with and ended up dumping as much money into it as they could have bought a stock Camaro SS or other pony car for :confused: The SS is close to the performance they want, right out of the box.

You're right, a Ferrari and a Chevelle would only be on the strip for a grudge race and even then I would call the Ferrari owner stupid for doing it. He/She has a Ferrari. They don't live on drag strips; they're more at home cruising in higher speeds or racing on a circuit where sustained high speed and hard cornering are involved. You don't beat on a Ferrari like you would to drag race. When you drive a Ferrari, you don't wind the engine up to 4000 RPM and dump the clutch, you'll end up breaking something very expensive. I remember Jay Leno making a comment about his ZO6. He said something to the effect of, "I can be rough with it, I can hurt it, I can do things in this car I won't do in my other cars because at the end of the day, it's still just a Chevrolet."

That's what I'm saying. Drag cars do not live in the upper RPM bands relative to other racing cars. If compared to a streetcar though? Hell no the drag car won't want to be @ 2500 RPM getting the best fuel economy, that's not what it was built to do.

In a perfect world drag racing vehicles wouldn't have to shift; or the fewer the shifts the better. Time is still lost due to shifting right? Or did physics change on me somehow?

Another of my friends, who had a Powerglide transmission, ditched it from his car and ended up selling it to a guy who was building a drag car because shifting once is as good as we can realistically do as of this point in time. Sure I suppose you could get a custom made 1.75:1 rear gear set, a transmission with one gear of 1.50:1 and have wheels/tires that are 28" tall. But what a slug that vehicle would be. It would be geared down so much that your 0-60 time would be rated in days, though the flip side is you could drive the quarter mile without shifting.

Because you don't want to shift often in a drag racing vehicle, don't you want power everywhere in the RPM band you can get it? Give me an imaginary drag racing car and say its redline is at 6000 revolutions per minute. When you reach 5500-5800 RPM it's time to shift. This is something we don't really want to do in drag racing, but we have to. So we shift and the needle drops down. The lower in the RPM band the needle drops, the longer the time it will be before you have to shift again. In this case you'd want a lot of torque in the low to mid-ranges to help you pull harder. If you can afford to have the needle drop to 2800-3300 RPM (into a meaty, broad torque band) you'll have power, you won't have to shift again for another 3000 RPM or so and you'll still be moving down the track at a very good clip. If the drag car shifts at the same 5500-5800 point and it drops to 4000 RPM, you'll have to end up having to shift again sooner and lose precious time. More shifting is bad in this case but it has to be done.

Ever watch an F1 or American Le Mans (sports car) race? Those are cars that race for miles upon miles and hour after hour. We can even use NASCRAP as an example here. They don't care if a shift takes a split second to perform because in the grand scheme of things, one half of a second lost due to a few shifts on a straightaway is a drop in the ocean when compared to the overall race taking: 2 hours, 3 hours, 500 miles, 24 hours... take your pick. F1 cars have peak torque and peak horsepower living right next door to one another. These cars live in the upper RPM band, more so than drag racing cars. I love the sound of an F1 car screaming through its gearbox as it drives along. They shift from gear to gear in no time, especially when they're slowing and start downshifting, they just bang that lever or paddle as quick as they can when they are approaching a corner. They don't want to drop below their power band so exiting the corner is a no brainer, just mash the throttle and keep it high in the revs while shifting. If you bog the engine, you could lose.

Yes indeed I was comparing apples to oranges with the Ferrari and Chevelle, you're right but that was also part of my point. The Ferrari on a drag strip looks like Gary Coleman on a basketball court (Thank you Motor Trend for that quote.) You just don't take the Ferrari to a drag strip and race it, that wasn't what they were designed to do.

I hate NASCRAP. I liked the comment that was made after a hired driver from the Trans-Am Series got out of the stock car (this was at Sears Point) and was
interviewed. He said, "I'm glad that race is over, I can't wait to get into a real racecar" (referring to his Trans-Am car.) Trans-Am was at Sears Point as a support series to NASCAR and the Trans-Am cars are purpose built for road racing. I don't know why these NASCRAP boys don't kick Sears Point and Watkins Glen out of their schedule, leave the twisties for cars that do them routinely. I like the twisty kinds of racing and it's hilarious to watch NASCRAP drive on a road course, so many of those drivers don't even know the stock car can turn right. The ones that do actually stay in the car, everyone else hires a driver who knows how to handle a car transitioning weight both side to side and fore/aft.

Ovals are boring to me, I'll watch racing at Lime Rock, Le Mans, Road Atlanta, Nuburgring, Laguna Seca or Burke-Lakefront Airport, for example, any day of the week.

Yes, that's quite true. Part of what makes a good sports car is doing very well in the quarter mile, but at the same time they don't have to. A stock Camaro SS doesn't have as high a top speed as a Modena 360, yet even the SS has a respectable quarter mile time. It just doesn't corner as hard as the Modena. Some cars fit into one category, others fit into plural categories.

Torque? Torque has always been around. Torque gets you moving. Horsepower is torque that introduces time to the equation. You're at a dead stop, no revving, no nothing, the car is idling and you punch the throttle (let's make traction a given.) Instantly your body gets shoved back hard into the seat, that's torque; good old American torque.

I love torque. I look at both specs when reviewing a car. But it's the torque you instantly feel when mashing the throttle. If I had a car that had both 600 lb. ft. of torque and 375 horsepower, I'd be more fond of my torque specs and gear the car more for utilizing that than the horsepower. I ran a video game test for this. I just had to. I can make hybrid cars in Gran Turismo 3, a real good driving game at that. I built up 3 different Vipers with the same amount of horsepower, but I did it in different ways. Because I made power in different ways, the RPM where the HP and TQ peaked were different. Everything was equal. I equipped all three with lightweight flywheels, triple plate clutches, a carbon drive shaft, super sticky tires and the same "sure-grip" rear end. I left everything else, including the transmission and rear gearing alone.

Viper 1 = 799 HP @ 5000 RPM 1186 TQ @ 4000 RPM (told it via a computer program that it had 799 HP stock) Average 400m = 10.568
Viper 2 = 799 HP @ 5000 RPM 1149 TQ @ 4500 RPM (turbocharged it via the computer program) Average 400m = 10.630
Viper 3 = 799 HP @ 5400 RPM 1095 TQ @ 4400 RPM (built it up using Viper parts from within the game) Average 400m 10.664

I can tell you now, to save time, the Viper that had the stock internal parts was easiest to make go the fastest because A) it makes the most torque and B) the torque hits sooner in the RPM band. It was also nice because after a shift, the needle dropped right into the meaty part of the torque band and climbed from there. If I had a Viper with 799 HP and say 500 TQ, there would have been no comparison. That car would have felt like it had fallen on its face when compared to the cars with 1000+ TQ. Just look at all 3 cars. Each have 799 HP, but by having more torque in a very usable location, the fastest car was faster by nearly a tenth.

Other stock streetcars I think are awesome are the Volvo S60R and the Audi S4 (the older V-6 Bi-Turbo model). The Volvo has peak torque of 295 available from 1950-5250 RPM. That torque curve is so flat, you could play a fair game of pool on it. In that car, you get to mash the throttle and feel the same torque pull basically just off idle until horsepower takes over sometime after 5252. Who cares where the needle falls after shifting; you've got the same amount of torque spread out through 3300 revolutions per minute. The S4 also has a flat torque curve, though not as dramatic. It has something like 295 lb. ft. from 1850-3600 RPM.

I will end by saying, you need torque and you need it in all the right places depending upon what kind of car you have; whether it be a street car, a road racing car, a truck or your grocery getter. Peak torque can be anywhere, or in the cases of the Volvo and Audi mentioned above, it can be spread out in more than one place. Use torque in conjunction with horsepower. Don't feel like you've got to say one is particularly better than the other, they're different, be thankful to have two power numbers, not just one. After all, without torque there wouldn't be any horsepower. Horsepower is just a mathematical function of torque.


[Modified by 1969Vette350, 5:43 PM 11/29/2003]

 

[QUOTE] My friend, in his 5200-pound truck, took a C5 off the line. The Corvette messed him up when he (my friend) ran out of gears to grab.

IMHO..a 5200lb truck with ONLY 400 ft/lbs of torque will NOT take a C5 or any other Vette off the line and through his gears... :bs

 

Holy Cripes! Are you one of the original authors of the Magna Carta! Do you REALLY think anyone is gonna READ all that???
I'm just going to pick the highlights...so much wrong here I don't have the time to go over all of it. Thank goodness for copy and paste!

"Yes, yes I do drive my Vette on the street. I don't go to a racetrack, and when I do, I'll take it to a road course."

No race courses by me and I wouldn't go on one anyway. I don't like repairing body damage. Plus road courses mainly measure the DRIVER and not the CAR. Strip is the way to measure the car. And the ONLY time that MATTERS is the time AFTER you pass the lights!!!! All that 60 foot and 1/8th mile stuff is :bs

I am not going to mix disputing street performance, which is TOTALLY MEANINGLESS, with race performance. We DON'T race on the street and that's that. 13 seconds does NOT seem all that easy to achieve, based on what is posted on this forum. At least, not for smallblocks. Not without spending a good chunk of change.

Saying a car is "more at home" in one place over anther is just YOUR opinion.
It doesn't necessarily make it SO. I have seen plenty of sports cars raced at the strip. Jay Leno can afford to power shift and pop the clutch on ANY car in his garage. So don't believe that junk he said.

"Drag cars do not live in the upper RPM bands relative to other racing cars."

Where in the world did you EVER come up with this ridiculous idea?????

Compared to ANY cars...drag cars LIVE at high RPM!! That's WHY you install all those heavy duty forged hardware parts. Not for tooting around under 2500 RPM.

"In a perfect world drag racing vehicles wouldn't have to shift; or the fewer the shifts the better. Time is still lost due to shifting right? Or did physics change on me somehow?"

Depends on the vehicle. Pro Stocks shift. I don't think rails and funny cars
do. Time is lost? Watch a Pro Stock race on ESPN. They do NOT lift the throttle and NO time is lost between shifts. The shifts are done at the TOP of the RPM band. There is NO RPM drop between shift...or an almost negligible one from the different gearing. Good lord man...they DON'T have a slow shift like those Formula 1 or NASCAR guys!!!!
Most drag racers that are GOOD never let off the gas and the RPM stays AT or ABOVE 6000 RPM, depending on what class and engine/trans they are running. They do NOT use the clutch at all. F1 cars, even with their short shift throw, end up shifting slower than a drag car, because they have to have a clutch that lasts the whole race. A drag car can replace a clutch after EACH run.

"The Ferrari on a drag strip looks like Gary Coleman on a basketball court (Thank you Motor Trend for that quote.)"

Interesting quote, but it's just more OPINION. Who CARES what it LOOKS like. PERFORMANCE is what matters. I don't care if a car looks like the clown car in Ringling Bros circus...if the freakin thing turns 10 secs through the 1/4 mile, THAT'S what MATTERS!!!
The Shelby AC Cobra wasn't "designed" for drag racing. It was "designed" for Vette-killing. It did BOTH VERY WELL.

Sports car races that take HOURS to finish and you only get to see SECTIONS of the track are boring to me. That's just personal preference.

Tork has always been "around". It just hasn't been emphasized until the reduction of horsepower numbers. Now I thnk we are seeing the emphasis placed on horsepower numbers again since the new Mustang Cobra is at 375HP and the new Vettes are even higher. Go into a showroom and ask a salesman how much tork a new Mustang Cobra or Z-06 has. He'll say "I dunno about that, but it's got TONS of horsepower!"

Dep

 

Ah, but he did. I never said he took the Vette through the gears, what I did say was that I believe the C5 driver was surprised at what the truck could do. After my friend crossed the intersection, the Vette was gone.