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Bruce The Goose
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M88 to M51 specs

#1

Post by Bruce The Goose »

Hi all,

I am planning on changing a M88 I have to civilian spec "adjustable high speed needle & M51 venturi" I see that I need to give the M88 an external vent, can someone please show me where this is located.
& do I just drill it & what size drill.

Cheers Bruce
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Re: M88 to M51 specs

#2

Post by Buddhahoodvatoloco »

Try and contact these stud muffins:
http://www.linkertcarbs.com/linkertDCparts.html
Bruce The Goose
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Re: M88 to M51 specs

#3

Post by Bruce The Goose »

Cheers
kitabel
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Re: M88 to M51 specs

#4

Post by kitabel »

Or just notch the venturi
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Re: M88 to M51 specs

#5

Post by kitabel »

In theory, the opening (either a horizontal hole drilled from the exterior to the venturi's annular groove for external air, or a notch in the venturi's leading radius at 6:00 o'clock position for filtered air) should affect the mixture curve (A:F ratio change with rising RPM).
I don't know if these two method's areas are even close, but given the wide range of engine sizes fitted with Linkert 1-1/4" models (25 hp 45" WLA to 38 hp 80" ULH) a valuable tuning aid is left on the table. High speed mixture tuned only by main jet size is not accurate unless the original engine tune and carburetor are used.
A really hot cam would suggest less air correction at high speed (common in V8 carburetors; a WL with a 4 bolt carburetor probably needs this as well), and this can be done by restricting the air by either method, but adjustable is more work. Threading the external hole and inserting a sized jet is one possible; the notch is a puzzle.

Indian used only internally vented (notched) venturis in all Linkert models (1" & 1-1/4") as far as I know.
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