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Does an LSD make a difference for straight line???

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Does an LSD make a difference for straight line???

Old 03-16-05, 11:42 PM
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Does an LSD make a difference for straight line???

Okay, i am pretty sure i know the answer to this...but i have a friend who is INSISTING that an LSD will not make a difference at all on a strictly drag car. Please help me find some real hard core data to back up this claim. This would be for a FWD honda drag car.
kris
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Old 03-17-05, 01:51 AM
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He's an idiot.

When one wheel loses traction in an open differential (which is very easy to do if your car makes any power) most of the energy from the driveshaft is concentrated to one side and that side spins very fast while the other side doesn't sping very much.. which means you don't go anywhere and get one nice single black mark on the pavement.

A Limited Slip Differential basically allows both axles to apply power under certain conditions which make it a lot easier to launch a car more effectively.

It's a lot more complicated than that but basically I can't think of any reason someone would want to run an open differential while drag racing.. they really suck for drag racing.

On a strictly drag car you would actually want to lock the rear axles together using a spool or a locking differential over using a LSD though.

Last edited by aramh; 03-17-05 at 01:54 AM.
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Old 03-17-05, 06:50 AM
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I have to agree with aramh.
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Old 03-17-05, 07:11 AM
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I agree with aramh, and will add one other: on a FWD car with an open diff, if one wheel starts spinning the car will drift toward that side, making matters even worse.
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Old 03-17-05, 07:40 PM
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thank you for addressing the FWD portion too. I dont really know how to convince this guy though.
kris
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Old 03-17-05, 08:38 PM
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It is pretty simple, ask him if 1 > 2, if he thinks so stop the argument because its hopeless. If he functions in the world with the rest of us where 2 > 1, while the LSD isn't really 2 (a locked diff is) it is > 1 and thus more traction than just 1 driven tire. There is a reason automakers put LSD on sports cars and don't bother on a Civic EX and it isn't because they just want to have a cool term to use or make it more expensive.
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Old 03-17-05, 11:07 PM
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Just show him this thread. If he still disagrees, tell him he is a moron for using a honda as a race car in the first place.
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Old 03-17-05, 11:56 PM
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hmmm, i cant say i agree with you fastcarfreak. A honda is a perfect car for a racecar. You should check out the hondata K20 supercharged track car. almost lapped everything in competition. My heart though, lies with the 7...a real TRACK CAR. thanks for the info guys. I just didnt want to be in the wrong. I told him i was done with it and il take my LSD over a one legger any day.
kris
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Old 03-18-05, 01:17 AM
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Yeah..."one wheel wonders" suck major a$$...IMO.
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Old 03-20-05, 11:31 PM
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Originally Posted by suprfast
hmmm, i cant say i agree with you fastcarfreak. A honda is a perfect car for a racecar.
The fact that other then the S2000, all hondas are fwd alone kills your theory that "a honda is a perfect car fro a racecar." There are tons more that add to this, but I think most people already know why your everyday honda is not made for racing. They do one thing, and only one thing well, they are very economical. Thats it.
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Old 03-24-05, 02:04 PM
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Originally Posted by fastcarfreak
The fact that other then the S2000, all hondas are fwd alone kills your theory that "a honda is a perfect car fro a racecar." There are tons more that add to this, but I think most people already know why your everyday honda is not made for racing. They do one thing, and only one thing well, they are very economical. Thats it.
hey dont make me defend FWD hondas!
I didnt build them for 4-5 years for nothing!

if I had twice the money into my Honda, then my FWD Honda would be as fast as my LS1FC in drag AND around a roadcourse. sure, FWD Hondas start out as econoboxes but the mods available nowadays can make them into very very serious competitors especially if you dont have any rules forcing limitations into the buildup. trust me, with 30 grand in performance mods on a swapped Honda that weighs under 1800 pounds and is on 13x8 wheels, you have a serious racecar that can close in on a lot of cars people think are blazing fast.

and of course an LSD makes a HUGE difference on a FWD drag car. FUGGIN' DUH!!
Most hardcore FWD drag guys run a Spool up front so they dont even have a diff! its just locked!

and why cant your friend do his own research? did he just imagine he knows it all some how? he sounds like an idiot.
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Old 03-24-05, 02:12 PM
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Originally Posted by fastcarfreak
The fact that other then the S2000, all hondas are fwd alone kills your theory that "a honda is a perfect car fro a racecar." There are tons more that add to this, but I think most people already know why your everyday honda is not made for racing. They do one thing, and only one thing well, they are very economical. Thats it.
Honda's can be very fast, even from the factory, with the correct alignment and a good driver. The driver, as with ANY car, is the key. FWD can be very fast, but they are harder to drive fast.
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Old 03-24-05, 02:17 PM
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Originally Posted by fastcarfreak
The fact that other then the S2000, all hondas are fwd alone kills your theory that "a honda is a perfect car fro a racecar." There are tons more that add to this, but I think most people already know why your everyday honda is not made for racing. They do one thing, and only one thing well, they are very economical. Thats it.
What about ITR's? Hondas/Acuras have done very well at the World Challenge Touring and GT series for years in EG hatches, Integra Type R's and now RSX's. The RealTime team does great. On the other hand Madza engines only last a few races, and they are the only team that isn't required to have their blocks last all season.
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Old 03-24-05, 02:17 PM
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since we're on the topic of differentials....anyone know how to install one? i'm totally clueless.....here's the thread i started if anyone can help me that would be great...

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/differential-install-question-407253/
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Old 03-24-05, 02:19 PM
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i've heard of a teg that was converted to rear wheel drive. something about using a tranny and rear subframe/suspention setup from a CRV. sounds pretty badass if you ask me. and hondas when done up right can definetly be fast.
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Old 03-24-05, 02:22 PM
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Originally Posted by suprfast
thank you for addressing the FWD portion too. I dont really know how to convince this guy though.
kris
Some people are just not worth enlightening or arguing with. Two of my cars (one Civic and one teg) have LSD in them and my bf's teg has one. Makes a big difference for launches and cornering. We autocross, and he's been at Sebring in his car.
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Old 03-24-05, 02:49 PM
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Thumbs up

Hondas do make excellent racecars.

They are inexpensive and readily available, and their numbers mean parts are very cheap. Their extensive following also means that all kinds of aftermarket goodies are available at relatively low prices.

What I find even more important is that they are very thoroughly engineered, particularly the engines. Honda engines can take serious abuse over long periods of time where most motors would have given up and died long ago. With few exceptions, there's always more power to be dragged out of them too.

And the rest of the vehicle is no slouch in the engineering department as well. Honda suspensions are very well designed and have versatile geometries - they adapt quite easily to road racing use. And their chassis are generally quite stiff for their weight.

I think Honda is pretty much the best in terms of engineering compromises. Obviously there are other cars that I would rather drive, but that's just a matter of personal preference IMHO.
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Old 03-24-05, 03:13 PM
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Oh yeah, and LSDs make a huge difference, for both drag and road racing. With an open diff, if one wheel slips, ALL of the engine's torque is transmitted to that wheel. The other wheels gets nothing, and the car does NOT accelerate. The spinning wheel scratching away at the pavement will only help to get the car crooked if anything.

An LSD ensures that some amount of torque will always make it to the other wheel as well, which can get the car to accelerate enough to get the spinning wheel to hook back up. But this is a transient condition, and it is not optimal for acceleration because you're still wasting torque on the spinning wheel. For drag racing, you would always want to use a locked diff/spool instead of an LSD. Since the car doesn't actually need to turn, there is no sense in allowing the left and right wheels to spin at different rates. That said, obviously, if your drag racing car also serves as a street car, you would certainly want an LSD instead.
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Old 03-24-05, 03:18 PM
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As for the orignal question in this thread, www.howstuffworks.com has a good section on differentials and the advantage and disadvantage of each kind.
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Old 03-25-05, 06:02 PM
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Anyone that is serious about racing will have a LSD, or locking rear end ........... Period!! Not having one is a big disadvantage.

As far as Honda's not being race cars, that's a joke. CRX's dominated in autocrossing for many years. I used to hate that I couldn't compete with them in my CSP FB. The top guys always beat me, and it wasn't because they were better drivers.

Last edited by adam c; 03-25-05 at 06:04 PM.
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Old 03-25-05, 07:19 PM
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Honda trannies blow......
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Old 03-27-05, 07:41 AM
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LSD makes a huge difference..... i had the one wheel peel on my sr20det swapped 240sx for about a month before it drove me nuts and i swapped to a vlsd out of a 300zx..... and since he was talking about drag racing my 60' times dropped a good 3 tenths on street tires from just that alone
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Old 02-20-18, 01:39 PM
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Originally Posted by fastcarfreak View Post
just show him this thread. If he still disagrees, tell him he is a moron for using a honda as a race car in the first place.
hahahahaha
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Old 02-21-18, 02:26 PM
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LSD equipped cars are fun! Everyone should have one!
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