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Discussion Starter #1
How silly is this? But it was there doing it's best.
This was forwarded to me: This "turbo" Dream made 76 mpg at Bonneville, and was "first in it's class" (were there others????). Shouldn't he have been able to do better? My stock Dream easily goes 65 on a flat road. The bike in the photo could be stripped down a lot more I think. Maybe the rider was heavy; who knows! I have a CA72 project just WAITING. The motor has been rebuilt so the rest can be "played with". Frame is all cut up so it's fodder for anything.




Beth
 

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That's a SUPERCHARGED Dream.
My guess is there is a lot of record opportunities in the small displacement categories for supercharged engine. Being that small engines can be difficult to supercharge or turbo charge with much efficiency.
It's probably running in a class that requires NO streamlining, meaning no fairing, nothing modified to make it slippery. Land Speed rules can be very....very specific.
It's quite possible a stock Dream can be made to go faster than this supercharged Dream until this bike gets sorted out. But for the time being, the supercharged bike holds the record in it's class because the class REQUIRES a supercharger.....if you see what I mean.
JohnnyB
 

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I was talking to my buddy JT about LSR two weeks ago, he is trying to get a lincoln mark VIII to do 200 mph. from what I understand weight is your friend at bonneville, it is a terminal velocity contest not an acceleration contest so weight plays a different roll. Apparently the top layer of salt is soft and you need weight to reach the hard layer underneath to get traction, so weight is your friend. He tells me that a majority of the bikes there are running up to 300lbs ballast weight by the swingarm. hoof would know more about that.

running on the salt is nothing like running on flat road. The more I think about it the more I want to do it. The suck thing about LSR for me is that mst of the vintage cutoff classes are 1959 or older. A cb750 gets bumped up into the same class a gsxr750 would run.

agreed, it is supercharged, not turbo.

I think the problem with that bike aside from the latent bad aero's is that it may not be geared and might not be sorted correctly. BTW, some supercharged classes don't require the supercharger to be hooked up, just that it has to be on the bike and spinning.

jb hit a lot of the points I was going to make also.
 

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Discussion Starter #4
I like the way they made a low profile front fender out of two stock front fenders, looks like

OK guys; please explain the difference between turbocharging and supercharging; I'm curious. Thanks
 

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quote:Originally posted by dreamqueen

I like the way they made a low profile front fender out of two stock front fenders, looks like

OK guys; please explain the difference between turbocharging and supercharging; I'm curious. Thanks
Both use a "pump" to pressurize the intake air. Supercharger is a mechanically driven pump (gears or belt usually), Turbocharger is driven by the exhaust from the engine.

Supercharger!

Turbocharger!
 

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A turbo is run off the exhaust while the supercharger runs off a belt on the engine. They do the same thing just they use different methods to spin up the compressor.
 

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Thats pretty interesting. I saw that photo on another site but really didn't pay a lot of attention to it. I looked up the 350 M/BG gas record and there is none. So, That meant he ran on an "open" record. Further meaning if no one has run that class before its open and whatever you run will be the record. He goes in the record book as the record holder and regardless of the speed he is a record holder. I have to admit I wouldn't brag but..... In case you're wondering, Scott Guthrie holds the unblown 350 record on a TZ at 140.
There are very specific rules about streamlining. There has to be. LSR guys are the cheatinest, most rule twistin' bunch you'd ever meet. Unstreamlined means just that. The SCTA even classifies a flat number plate on the front forks as streamlining. They have to, because if they didn't you'd find someone showing up with a Burt Munro streamliner calling it nothing more than a front number plate.
 

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quote:Originally posted by Hoofhearted

The SCTA even classifies a flat number plate on the front forks as streamlining. They have to, because if they didn't you'd find someone showing up with a Burt Munro streamliner calling it nothing more than a front number plate.
same rule for ahrma clubman. i know ther ehave been cases of people being protested for a tipped number plate.

jc
 

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here is another question...does the scta make a distinction between 350 2 stroke and 350 4 stroke?

I really need to get a rule book
 

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The SCTA has two basic classes for motors. OHC four strokes run with two strokes and there is a seperate class for pushrod motors. I know there is a list somewhere for all the classes. But I'll have to go search to see where its listed. I'll get back.
 

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lots of LSR infor here: http://www.landracing.com//

a note on super/turbo charging....another difference is where the boost "comes on". superchargers are more linear, providing boost from a lower point all the way up. turbo's need to spool, the boost doesn't kick in fully until you're higher up in the rev range. of course, if you're really going to go all out, you stack a turbo and super charger together, the best of both worlds! or...you run a smaller turbo into a bigger turbo. it all depends on how you want to make the power. i've heard of using NO2 to help kick the turbo as well. if you want to see turbocharging taken to an extreme, look at some of the Audi Pike's Peak racers, those guys ran between 42 and 50 pounds of boost. most semi-sane people consider anything over 20 pounds to be too much (if you like your cylinder head, anyway).
 

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super charging quiz: how many horsepower does a top fuel dragster use to spin its supercharger? geet and hacka...give someone else a chance...and hold your breath!
 

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From what I understand its about 500. If you're making 8000 and can smole the tires anytime 500 is no big deal.
 

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right you are hoof, it's like 500-900 hp to spin them puppies. but, like you said, the end result is 8000hp. and 8000 hp is just cool.
 

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We got a taco stand here in Riverside that sells tacos that'll go through you quicker that Burt Munro's Indian in the lights.
 
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