can you have carbs that are to big for your ski? 49mm full spectrums

[DezKnotz]

i have a 62t ported top and epoxy cases b pipe msd fly light weight fly wheel ada head running pump gas nothing crazy and last year i put on a set of 49mm full spectrums and high volacity intake set up on my ski and i feel like it ran better with stock carbs. wtf the ski ran good but idk if i cant get it tunned right or if they are just to big

 

[OCD Solutions]

Did you end up with reverse jetting?

 

[restosud]

could be a little too large for a mild setup.
had a very similar setup with modded oem 38 and it hit like a ton of bricks.tried riva 48 and lost some snap.

 

[WB800BLASTER]

yes i think some people go way toooooo big. Me i think you should be at max dual 46's

read the Mikuni manual there is a section that cover carb sizes and needle seats. this tells you just about all you need to know.

 

[DezKnotz]

no i think thats all good

 

[DezKnotz]

i feel like the ski had more bottom end pop with just my stock carbs

 

[OCD Solutions]

I think it all depends on the amount of airflow and signal strength that your setup creates. I ran a set of Novi 48's on my Seadoo 951 and they had such low signal on the bottom that I ended up running reverse jetting to get enough fuel thru them. My pilots were 150 and my mains were 145. I would have had way better luck with a set of 44's and spent much less.

Carbs, like anything else have to be matched to the engine. Sure larger carbs can work, but the better matched they are, the better the results will be.

 

[MNTURBO]

i heard 44's are as big as you want to go on a stock bore/stroke

 

[Mark44]

Yes you can go too big.

Mark44

 

[masterblaster]

Not sure I agree here,the fs 49 is really getting the signal of a 46 anyway,its got a necked down venturi around the booster. you just need to experiment a little with jetting,fs carbs hit hard off the bottom at wot bud,they have some other issues with little stuff in the mid range for rec riddin but hittn hard off bottom is their strong point.
I have riddin straight novi and fs 48s on a lim 701 setup that hit super hard.that said for these small motors I think 46s can deliver the same amount of power,for alot less $.But the 48s or 49s are not hindering it whatsoever jetted right.
If your cases are epoxy and ported,you might try stuffers. By high speed intake to you mean a boyesen intake with epoxy in to consume a little of the extra space to get a little quicker responce? Maybe try checking your timing with that flywheel and make sure you have around 24 deg static advance?

 

[restosud]

the max on that setup would be 44's but 38's would be fine as well.

 

[GIL]

I am running a 838cc Lamey big bore stroker and my guy told me that 46s would perform better than 48's. I am running the 46's and LOVE em.

 

[scottie mac]

49s would be fine for your set up as long as they are tuned properly. We run 48mil Novis on spec, unported 701s and they run like a top.

Scottie

 

[masterblaster]

gil,for sure as good,but better,highly questionable. everyone is trying to sell something,you should hear these carb guys talk about the "other" carb guys. Its laughable really

 

[waxhead]

Its not the size of the carb but the signal strength it delievers
This is why a novi can pull harder on a jet than a stock 46
To stipulate a carb size you need to stipulate a carb brand there are some carbs out there that have crap signal and there are some that dont.
The carb that doesnt pull hard on the jets will have to be smaller and then retuned when the clouds come over and change the relative air density

 

[masterblaster]

I hear this change in the weather and air density but have never noticed it with any carb,how much change are you talkin about? seasons?

 

[kevbo]

Look a little closer at the carbs design than just the size of its throttle plate. The venturi needs to be the smallest area of the entire intake tract. If its not then expect tuning problems. A stock sbn44 venturi is just under 40mm and the large butterfly area means that its not in the way. A 44 I-body has a 42mm venturi which flows more and has much less signal than the SBN. The main jet requirements tell everything, when they start getting large then the carb is too big or its design simply wont pull fuel very well.