Can someone explain what this is, how much it costs, what gains I should expect and how do I get it.
thank you
Can someone explain what this is, how much it costs, what gains I should expect and how do I get it.
thank you
It is taking the back part of the top of the cowling, removing it and placing some longer bolts and 1/2" plastic spacers in the mounting holes and remounting the "scoop". This raises it up and allows more air in. You also have to drill some holes in the top of the cowling from underneath, to make it functional. I'll see if I still have some pics.....
cowtrimmer has some great info on this mod...its pretty simple...other than the drilling part..![]()
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total cost may be 5 dollars or less...150 to 250 rpm...
LD
Try this guys.Under the bottom cowls on both sides under the intake butterflies drill 3 holes 3/8 in diameter 2 side by side and 1 behind, get a chrome 1 inch clam shell( the ones you buy for covering cable through hull) and silicone it over the holes facing forward. I also siliconed window screen over inside of holes to keep trash from blowing in. This will really put the air where you need it.I did it to a stock 225 and it shut down to 2 grand due to lean condition(too much air).On my current 250XB it works well and is hardly visible.I also have the hood mod. The more air the merrier.![]()
Richard
I did the mod on mine, and gained about 200+ rpm, and 2mph.not to bad for a $5.00 mod.
To all the guys that asked me to post some pics here ya go...
Don't forget to drill a couple of holes in the top of the cowling (in the area covered by the air scoop)![]()
Where exactly do you drill the holes under the cowl?? there is 2 - 1" holes where the plastic plugs go which cover up where you access 2 of the cowl bolts. Do you cover these or leave them open.
More pics on instructions would be appreciated.
Good start but you need more holes drilled in that inside cover.
Richard
anyone else have more pics,,, the more the better
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mr70ss »</TD></TR><TR><TD CLASS="quote">more pics
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Mine looks basically the same except there are more holes drilled in there.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kllr bee »</TD></TR><TR><TD CLASS="quote">I did it to a stock 225 and it shut down to 2 grand due to lean condition(too much air).
Richard</TD></TR></TABLE>
What do you mean it shut down? And where did you get the spacers?
Noland
"Slower than a speeding Bullet, but faster than a Cookie Cutter."
I got my spacers at my local hardware store (lowes)
The longer stainless steel bolts and plastic spacers can be found at any True Value type hardware store. It will cost you more in gas to drive to the store and back than the parts for this mod will.![]()
how many holes total is good, and how big should the holes be, thanks.
I drilled 3 holes 3/8 inch in diameter in the bottom cowl under the intake butterflies and put a clam shell like you put over through hull cables and had them facing forward.there was so much extra air to the motor that it would shut down to 2000 rpms with a 225 fuel computer. If you stopped them up the motor ran fine. With the 250XB or 300 Pro Max ecu's it would run excellent.I have that and the cowl mod using the 250XB fuel computer.
Richard
PS Don't tell anybody this is one of those things I don't want anyone to know about.![]()
How much did the extra 3 holes give you for rpm and top end vs with just the cowl mod??
Also how many holes in the cowl do I drill and how big ??
I really don't remember how much it added. I have done so many different things I forget.But I remember it shutting the motor down and the only thing that stopped it with the 225 computer was stuffing paper in it to stop it up. I put a bunch of holes in the inside of the cowl,like 8 - 1 1/2 inch holes.
Richard
Can you give the XB too much air vs fuel, or will the computer monitor it.
Just curious as it runs very rich at idle.