Modern Vespa

If I plan on modding/building ( malossi cylinder/head, cam, etc.) an engine. Does it matter if I start out with a 250 or 300 engine for the most bang my my buck?

I have no idea but I love it I will subscribe to the thread if you start. With most car engines bigger is better. No replacement for displacement.

Exactly. That is what I am thinking of, but with the Vespas it seems that the cylinder and heads seem to work with the 200/250/300 motors all the same. So not sure lol

I have a 250 currently so am looking for a 300 project bike, but if its all the same I will also snatch up another 250 just the same.

Put the BV 400 motor in it. Would take lots of doing, but what a great motor.

Cmon bro. Don't tempt me haha

I didn't fool around, and just went straight to 'Stoooopid size' and got it over with.

Probably not, but early 300s are going pretty cheap.

Malossi kit displacement 250 vs 300 is 269cc vs 282.

The 300 motor has a slightly longer stroke than the 250.

note the malossi v4 head is not needed for an hpe as it has the same size valves. hence malossi doesn't list it as compat

This should fit

Ahh okay. These are the answers I was looking for. I will likely hold out for a 300 or 300 engine. I had a 2012, but the frame was rusted to shit so I sold it and broke even.

I know you asked what to start with, but my (sometimes feeble) brain starts turning quickly and I can't shut it off. New Cylinder and head are the most obvious places to start - increasing displacement will only get you part way there.

A performance camshaft with longer lift duration will make the most of the new head and cylinder.

Follow that with modified airbox and a quality performance exhaust - PM Tuning would be my 1st choice; Akrapovic, Scorpion, and Leo Vince after that.

You'll likely need an upgrade to the fuel maps as well, Malossi Forcemaster comes to mind.

Taller gearing will be needed to get the most out of the upgrades. You can achieve this partly by upsizing the rear tire, but a true gear swap will net you even more.

Performance transmission parts from Malossi or Polini should not be forgotten to help get more of that power to the rear wheel.

Don't forget brakes and suspension...with increased power, you'll want better control and improved stopping power.

Now go build this thing...and share plenty of pics!

^^ all that plus a larger throttle body can also help

I plan on doing all of this. Just wanted to know if there is a difference betweek doing all of this on a 250 engine vs. a 300 engine. It appears that there is so that is my first step; finding a suitable project bike.