Which is faster?? The srx 440 or the 540

Undertaker#13 · Post by **Undertaker#13** » Sun Aug 16, 2009 7:54 pm

tyler my VMAX is bone stock, I have been to the tear down shack a couple of times

Undertaker#13 · Post by **Undertaker#13** » Sun Aug 16, 2009 8:01 pm

The SRX that I can't beat in 1000 ft is a 1977 mod srx! The guy runs 105 mph in 1000ft

Undertaker#13 · Post by **Undertaker#13** » Sun Aug 16, 2009 8:12 pm

tyler440 wrote:sure no stock srx will beat your precisly tuned racer.... no stock(street) impala can beat a nascar toyota camry either i dodnt know which will beat which because ive never seen them lined up side by side... and even if they were you cant guarantee that which one will win evertime, everyday... beside not all of us go straight on ice... you cant just think that the 540 has 100 more cc's than a 440 so it has to be faster... you do realize that stock the 440 actually has more HP, cause thats a fact....

my personal opinion is that the 540 is faster, because it has more torque to get out of the hole but i wouldnt not be a damn bit suprised to get my ass handed to me by a 81... they really wind and actually make more power.... i think there are too many factors to say for sure

beside not all of us go straight on ice... you cant just think that the 540 has 100 more cc's than a 440 so it has to be faster... you do realize that stock the 440 actually has more HP, cause thats a fact.... that is your choice! You have stated your opion! My opion No 81 stock srx will out run a 540 VMAX!!

Post by **tyler440** » Sun Aug 16, 2009 8:50 pm

i too own a stock 84 vmax that runs like nobodys business, and im pretty sure it would beat a 81 but no one can know for sure until it happens... and even if it did there would be too many factors... as there always is when racing something that depends on soo much.... drag racing anything is not easy by anymeans... how much do you have to change when you go from running 660 to 1000? i imagine you got at least a couple clutch tricks you do, you'de have to...

all i am saying is if i was riding somewhere and i ran across i guy that had a 81 and he wanted to race "from here to sign" i would not take him lightly because he is lacking 100cc...

Bob Vehring · Post by **Bob Vehring** » Mon Aug 17, 2009 12:56 am

Guys, hate to show my age, My first trip to a dragstrip happened in 1964 have raced continuously since then. Conversations like this have gone on every day and always will
Check out our site, http://www.4cyclecentral.com float around on some of the picture pages to see some of the stuff we build. Some of the things are clearly race only but many of the things like sleds are meant to look stock, but really far from it. The SRV other then paint looks stock, not much of it is, and its 60 # lighter then my V max started out at. one of the drag sleds started out from a '76 A/C I built around 79 for the trails, it had a good (for then ) rear skid, and was light. With Alum skis and a light track it was under 400. It had a 440 liqud Rupp engine. Under the stock seat was a 1 qt fuel tank and one small heat exchanger, but it looked stock.

Basic rule number 1, when someone wants to race, never assume its stock

YAMMIEGOD 3:16 · Post by **YAMMIEGOD 3:16** » Mon Aug 17, 2009 5:22 pm

GREAT POST GUYS. I HAVE HAD BOTH SLEDS AND LOVE MY 1983 VMAX. HERE IS THE STOCK FOR STOCK RESULTS (my expreince ). 81 SRX WOULD BLOW THE VMAX AWAY FROM THROTTLE ON TO THROTTLE OFF. REALLY NO COMPARISON. 81 SRX HAD MORE HP, BETTER SKID FOR DRAG RACING, EXTEMELY HIGH RPM PORTING, ING, PIPES, HEADS EVERYTHING WAS BETTER. WHEN YAMAHA CAME OUT WITH THE VMAX IN 83, NOT ONLY WAS IT JETTED FAT, IT WAS OVER OILED, AND VERY CONSERVATIVELY PORTED. YAMAHA R&D CAME TO THE RESCUE IN 84 WITH UPDATE PORTING BECAUSE 83 VMAX WAS HAVEING TROUBLE ON THE LAKES. THE 81 SRX CLEARLY WINS THIS MATCH. SORRY GUYS. I LIVED IT, SAW IT AND DID IT. 81 SRX WERE PROBLEY AS CLOSE TO A 77 SRX AS FARR A ENGINE PERFORMANCE OF ALL THE SRX,s. FOLKLORE SAYS THE 82 SRX 500 WAS EVEN MORE RADICAL. 3:16 (yammie tony)

vmax-540 · Post by **vmax-540** » Mon Aug 17, 2009 5:37 pm

If we are talking stock for stock,and we have to realize that anything can happen on any given day then either one of these sleds can beat the other. I have both sleds and my Vmax is as strong as any other and if you are talking flat out across a lake the the SRX will take it more times then not. Yamaha said (and it is true,verified by radar by a lot of people) that the SRX will hit 104-106 MPH on top end,the Vmax is by far a lot quicker sled out of the hole up though mid range ,hence the faster times in 1000 ft. If you look at it mathematically the SRX had a stock gear ratio of 1.82 at 9250 rpms the Vmax had a ratio of 1.83 at 8,250 rpms ,it's not hard to see which one would have a higher top end. When Yamaha came out with the update porting it was almost exactly the same porting layout as the 81 SRX porting, I had my Vmax ported to the update porting and it made a big difference in the way it performed,it may of been fast enough to beet a SRX on top end ,but I never ran one back then so I don't know for sure. When I restored my Vmax I put it all back stock,but I have some more cylinders that I am thinking of having ported to the update specs and reinstall them.
As far as I am concerned I love them both,they feel nothing alike,the SRX feels like the old lake racers and the Vmax feels like a more modern sled with lots of mid range and a LOT better ride. Yes the Vmax was way ahead of it's time but the SRX wasn't and isn't as bad as a lot of people have said they are. LONG LIVE THEM BOTH!!!!!

Undertaker#13 · Post by **Undertaker#13** » Mon Aug 17, 2009 6:11 pm

Bob Vehring wrote:Guys, hate to show my age, My first trip to a dragstrip happened in 1964 have raced continuously since then. Conversations like this have gone on every day and always will
Check out our site, http://www.4cyclecentral.com float around on some of the picture pages to see some of the stuff we build. Some of the things are clearly race only but many of the things like sleds are meant to look stock, but really far from it. The SRV other then paint looks stock, not much of it is, and its 60 # lighter then my V max started out at. one of the drag sleds started out from a '76 A/C I built around 79 for the trails, it had a good (for then ) rear skid, and was light. With Alum skis and a light track it was under 400. It had a 440 liqud Rupp engine. Under the stock seat was a 1 qt fuel tank and one small heat exchanger, but it looked stock.

Basic rule number 1, when someone wants to race, never assume its stock

that was the year, I was born!

YAMMIEGOD 3:16 · Post by **YAMMIEGOD 3:16** » Mon Aug 17, 2009 6:30 pm

BACK AROUND I BELIEVE WINTER OF 81-82 I WAS TERRORING EVERYBODY A NEW AHOLE WITH MY BRAND NEW 1979 SRX. WELL ONE DAY I WAS ON ONE OF OUR LOCAL LAKES CLIPING ALONG WHEN OUT OF KNOW PLACE TWO 81 SRX,s CAME ON BOTH SIDES OF ME. WELL WE ALL HIT THE GAS AT THE SAME TIME , I WAS SUCKING SNOW DUST REAL FAST. THEY LEFT ME. I BASISLY REALIZED I MADE THE MISTAKE OF RACING THEM AT THEIR GAME. WHICH WAS PROBLEY A 60 mph ROLL ON. I THAN CAUGHT THEM AND CHALLENGED THEM TO RACE ME IN 660. THEY BOTH SHOOK THEIR HEADS NO. THE WINTER OF 83-84 TOOK THIS SAME SRX UP TO BIG MOOSE LAKE IN UPSTATE NY,THE HOT SPOT FOR NY RACING. THERE WAS BRAND NEW VMAX 540 ALL OVER THE PLACE. RACED THEM ANY WAY THEY WANTED, DEAD STOP, ROLL ON, YOU NAME IT!!! HAD ONE GUY RUN RIGHT UP MY trailor to race!! HE COULD NOT BELIEVE HE LOST, TRUE STORIE GUYS. , STILL HAVE SRX. 3;16 (yammie tony)

vmax-540 · Post by **vmax-540** » Mon Aug 17, 2009 7:29 pm

Hay Tony Is that when you went out and bought a 81 SRX !! For a sled that is supposed to be such a piece of junk ,they sure surprised a lot of people . I think the only people that appreciated them were people that owned them. Correct me if I am wrong but when it comes to top end I think it would run with most if not all 600cc and maybe 700cc of the new sleds out there today. Buy the way mist seeing you at Boonville ,Mark said you were busy.

Undertaker#13 · Post by **Undertaker#13** » Mon Aug 17, 2009 7:54 pm

The biggest cc sled that I beat in 1000 ft with the VMAX was a INDY 650! I was

YAMMIEGOD 3:16 · Post by **YAMMIEGOD 3:16** » Mon Aug 17, 2009 8:51 pm

HELLO TO YOU JEFF. ACTUALLY I RAN OUT AND ORERD A 82 500 lol. 81 srx 440 e was a great sled. even almost thirty years latter, no sled looks meaner. the darth vader of snow. problem with the 81 srx was it was a case of a race / lake monster that people wanted to put/put/ ALONG THE TRAIL. WITH A MOTOR THAT BASISLY THROUGH UP ON ITSELF UNTIL IT HIT 6000 RPM, THERE WAS NO HAPPY MIDDLE GROUND. JUST LIKE TODAY, PEOPLE RATHER RIDE, THAN RACE. THE ONE YOU HAVE THAT I OWNED I BELIEVE I FOUND IN THE EARLY NINTIES NOT 5 MINUTES FROM MY HOUSE. I DID TRACK IT DOWN TO WHERE IT WAS SOLD NEW FROM A DEALER IN ALBANY AREA. THAT SLED WAS AS GOOD TO ME AS ANY SRX I HAD, AND I HAVE HAD AFEW. NOW IT BE TUFF BY TODAYS STANDARDS FOR IT BECAUSE NEW SLEDS ARE SO FAST, BUT IT WOULD INPRESS. AND LOOK, I AM NOT SAYING THE VMAX 540 WAS NOT A GREAT SLED, I LOVE MINE, BUT IT SORTA PAID FOR THE SINS OF THE 81SRX. 3;16 (yammie tony)

Bob Vehring · Post by **Bob Vehring** » Mon Aug 17, 2009 11:31 pm

Back then so few people new about the Big Blue Bottle

and the heat exchanger kept the bottle temp stable. You did learn not to go off jumps while sitting on the seat, damn that hurt..
So, anyplace these up date port spec's are printed? haven't decided what to do to the engine yet, still trying to make the old wreck look good.
Any of you guys from S.E. Wi.?

vmax-540 · Post by **vmax-540** » Tue Aug 18, 2009 6:23 am

Bob the update porting specs are in the article index in this site. They do make a big difference , had mine done years ago and took them off and sold them when I restored my sled .(what was I thinking)lol. This winter I am doing another set up and put them back on.

Bob Vehring · Post by **Bob Vehring** » Tue Aug 18, 2009 10:41 am

Jeff So far I haven't really worked on this engine at all, and know little about it .I have read many of the "stories" but been around long enough to know mostly the are just stories

I do have a friend who today mostly builds Ski Doo and Pol. engines but years ago raced these extensively, I haven't sat down with him over this engine on the bench yet, but we have talked. His thoughts were the ex port was to wide, stock, for the bore dia and so the problems that did happen, happened because of snagging the ring. His plan, which he has done in the past, was to simply use a larger bore and piston. My cyl's do have liners in them already, so half the works done, but I haven't measured the port width yet, they do not look to have been ported.
I started a few weeks ago on the chassis, and still need to paint everything, made some progress but now of course we got busy, and other projects in the way. If I get to the engine soon enough, I'd like to build the thing, If I run short of time, it will go back together just with new pistons and be mostly stock for now. Sounds like you have had good luck with them that way. Did you ever dyno the two different port designs? and does the update porting need any changes to the pipe to take full advantage of it?