Best place to drill for pulse line?

Yup, we are talking about the same thing my friend.

It's a 372xp (Hyway big bore cylinder) 52mm bore and 38mm stroke.

Just for clarification on your question, are you talking about the 372xp build or the carb? Regarding the transfer being the best place, that appears to be the consensus.
On a 372xp saw the pulse would come from the port on a Walbro carb. To use a Tilly on it you will need a pulse line.
My question was for the build itself, if you fill in the transfers on the case then there is no place for the pulse port. Not in the transfer anyway.
An adapter plate will just cover over the gap and leave a nice spot for the barb.

Of course this assuming you're use a typical CG bottom end.
 
On a 372xp saw the pulse would come from the port on a Walbro carb. To use a Tilly on it you will need a pulse line.
My question was for the build itself, if you fill in the transfers on the case then there is no place for the pulse port. Not in the transfer anyway.
An adapter plate will just cover over the gap and leave a nice spot for the barb.

Of course this assuming you're use a typical CG bottom end.
Few things

1) I'm not using a Walbro carb, I am using a Tillotson carb that has an external pulse. Unlike the "internal pulse" where there will be an inlet on the intake side of the carb, this has a barb for external pulse.

2) On the 372, you don't fill in the transfers as you would on a 440/460.

3) It's on a modified 372xp case.

Photo #1 - Left case is a stock YD case, the case on the right is my case. Notice how it doesn't have that shine to it? It's been decked flat. Also if you look closely, notice anything different with the case on the right? There aren't M8 holes. They were never filled because they don't exist. It is a completely blank YD case :cool:

Photo #2 - As the YD transfers in general aren't the best, and 66cc/69cc by far has better transfers (BT100 is probably the best) I was able to have them slanted downwards more as the YD transfers are completely flat on the bottom. I'll still be able to drill for the impulse barb though.
 

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