HIGH R.P.M.'S AT WIDE OPEN THROTTLE

[THE BOSTON SIDEWINDER]

TOWARD THE END OF LAST SEASON (WHEN IT GOT SOOO COLD I HAD TO PULL THE BOAT FOR THE WINTER), I WAS GETTING ABOUT 5300 RPM OUT OF MY PRETTY MUCH STOCK 454. I THINK THAT'S TOO HIGH, RIGHT? TO GET THE RPM'S DOWN I HEARD I SHOULD GO TO A 'B' IMPELLER, AND/OR CHECK WEAR RING/IMPELLER CLEARANCE(IT MIGHT BE TOO MUCH GAP).
I'M NOT SURE WHAT I'M RUNNING FOR AN IMPERRLER NOW.
ANY OPINIONS ON THIS WOULD BE APPRECIATED!

[Jordy]

What were you running RPM wise for most of the season? Was the 5300 a change? If so, it would indicate that the pump is loosening up tolerance wise if you didn't change anything else. Did anything else happen, like cavitation out of the hole?

[THE BOSTON SIDEWINDER]

I HAVE DONE SOME IGNITION MODS(WIRES, WEIGHTS, SPRINGS, TIMING) BUT OTHER THAN COLDER THAN USUAL WEATHER THAT'S IT.

[77charger]

if you want to lower your rpm DO NOT GO TO A B CUT IMPELLER!it is a smaller one and will increase rpm by about 250-300.Check your pumps clearnces to see if it is time fora rebuild.

[sidewound]

The best thing to do first is probably check your pumps clearances. And better yet, It's Way CHEAPER
Peace Man

[miller19j]

If you are running a stock 454 with an A impeller I am going to bet it is time to rebuild your jet. Pull it apart and check the clearances. Like said before don’t switch to a B Impeller.
But before you do that hit the caps lock button on your keyboard. :D

[Mohavekid]

I doubt the changes you made significantly increased your power output, nor do I think the cooler air would give you that much more power to spin that impeller that fast.
A pump rebuild looks to be in your future.

[BK]

Im pulling 5200 with 500hp Chevy and a tight pump with an A/B impeller and I had a 100rpm increase on NYD with the colder weather so thats not going to make a big differance. I would definately check your pump clearances and if you noticed a sudden increase in rpm look to see if you have something small stuck in there as well, just a though.

[jim@pj]

It definatly sounds like your pump is getting too tired. What kind of intake are you running? A stock grate will get you high speed cavatation that result in extra rpms. Usually when a wear ring clearance starts to go away your hole shot performance goes with it. How does your boat pull out of the hole? I sell loaders that will pull your rpms down and get you more speed. Check out my web. Thanks Jim

[THE BOSTON SIDEWINDER]

THANKS JIM, THE HOLE SHOT IS STRONG, AND I'VE BEEN THINKING OF A NEW LOADER. DO THE ONES YOU HAVE GIVE ME SOME KIND OF ROCK PROTECTION LIKE MY OLD STOCK GRATE DOES(I DEFINATELY NEED THAT ).
WHAT IS YOUR WEB SITE, I'LL CHECK IT OUT.
I LIKE CAPS LOCK, THEN I DON'T HAVE TO WORRY ABOUT CAPS ON ANYTHING! OH WELL I guess maybe I could change that...Bill.

[Mandelon]

I heard if you want to lower rpm, you could just disconnect one of the spark plug wires.. wink

[waterroach]

What is too big of a gap between the wear ring& impeller.

[jim@pj]

Bill.. My loaders are not as protective as the stock grate for rocks, I don't think that any performance loader is as pretective as the stock units. If you are coming out of the hole strong then you probably have some high end slip. How fast are you going.? Don't pull your jet yet. Give me a call or contact my web. www.performancejet.com (http://www.performancejet.com) Jim

[THE BOSTON SIDEWINDER]

THANKS JIM, I'LL E MAIL YOU NOW...BILL.