Found this when i googled

[- Superman vs. Flash -]
Okay, this is absolutely ridiculous. I'm sick and tired of having this conversation over and over so here's the real lowdown
Race 1 - Superman #199
The day, June 10th. The mood, tense. Actually, let's start off with how the race actually came about. The Secretary General of the United Nations called Superman and Flash in for a little chat. He explained to them that the UN's funds for the sick and hungry was running dry and hoped that the two super heroes would put on a race to help raise money for the fund. Of course they both agreed, being the compassionate super heroes that they are and it was set. Now for those of us who are betting men it is quite obvious that a race like this without any action would be more masturbation than race...I mean let's be serious. It just so happens that there are going to be some HEAVY wagers placed on both sides of the table. The American syndicate placed a on Superman to the tune of one million dollars. To make sure that Superman won, Mr. Vincent retained the services of one Dr. Werner Von Broder to create a fake Flash that was fast enough to keep up with Superman, but could never beat him*. The Continental crime syndicate also would like to protect their investment and asked Dr. Rober Carson to make sure that Flash was the winner of this race. Back to race day...the rules were simple: they would race three times around the world and Superman was not allowed to fly (of course). The starting pistol sounds and the racers are off. There are a few hiccups during the first two laps around the world but to make a long story short they are neck and neck going into the final lap. This is where I think that things get a little too coincidental. Somewhere in Nevada, both crime syndicates have set their traps...Flash was stopped with bulletproof glass and Superman was brought to a halt with a little bit of the ol' K dust. Simultaneously the fake Superman and Flash are released (yes, apparently Mr. Carson decided on a rocket-powered double himself) and they continue on towards the finish line. Obviously since both super hero doubles were programmed to lose, neither one of them crossed the finish line and they started arguing. About this time some gayness happens and superman frees Flash and visa versa and they cross the finish line at exactly the same time. A rather disappointing outcome indeed...
RESULT: TIE
SCORE: Superman 1/2 - Flash 1/2
* - The plan called for the Flash lookalike to be propelled by rocket-powered boots which in my opinion is a ridiculous idea as it could never keep an object traveling at a speed needed to stay competitive (~140,000 mph in this version).
Race 2 - Flash #175
Let's hope this race has a somewhat better outcome. It started when Flash and Superman crossed paths answering the JLA signaler. When they discovered that neither one of them had actually issued a signal they both hurried over JLA headquarters. The other members of the League were gone and they found two alien gamblers in their place, Rokk and Sorban. These two had put some money on the first race, and not being satisfied with the output insisted that they race again. As a little incentive, if Flash were to lose, Central City would be destroyed and if Superman lost, Metropolis would be destroyed. Not having much of a choice the super heroes agreed to race. Instead of racing around the earth, this time they would race to the edge of the Milky Way Galaxy and back, which is about 40,000 light-years away. The first thing that you should be asking yourself is "that's stupid, Flash won't be able to breath in space". Well someone came up with the ridiculous idea to surrounding Flash with an aura that changed interstellar dust into oxygen for him to breath, and a walkway on which to run. Anyway, long story short, some time during the race Superman learns that Rokk and Sorban aren't even ON earth and are back on their home plant gambling on volcanic eruptions. So Flash and Superman decide to head back to earth. They find that the impostors are Kadabra and Reverse-Flash and the race was part of a plot to put the kibosh on Flash. Once again we are left with a tie. On a side note, I must mention that the reason a winner could not be decided in this race is because they were travelling so fast when they crossed the finish line that their true state could not be measured. Now I'm not one to argue with DC's interpretation of quantum mechanics, what I do wonder about is why they continued to race after they found out that it was just a big setup? I guess we'll just chalk this one up to these guys being some bad ass mo'fos once again.
RESULT: TIE
SCORE: Superman 1 - Flash 1
Race 3 - World's Finest #198 and #199
This debacle took two comics to unveil. It gets pretty tricky so watch out. Apparently, time distortions start swapping people between eras on Earth and the Guardians of the Universe summoned Flash and Superman. It turned out that there were a group of faster than light Anachronids were interfering with the flow of time and if two people could travel at similar speeds in the opposite direction of these beasts, their signal would be disrupted. So they start off running and Flash suggests that they make it a race since their two previous races ended in ties (as we all well know). Superman, not being the type to back down says giddy up and they are off. Long story short, a fight here, a fight there and Flash gets to the Anachronids' power switch before Superman....finally we have a decisive winner!
RESULT: FLASH WINS
SCORE: Superman 1 - Flash 2
THE FLASH IS THE FASTEST MAN ALIVE! ANY ATTEMPT TO PROVE OTHERWISE IS WORTHLESS AS THE COMICS SPEAK FOR THEMSELVES!
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