Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Engine upgrade

I know there was a prototype that Morgan West had with the new S&S 124 engine. Has anyone replaced a stock engine with it? What about the CARB rules in California? I've read conflicting articles on whether you can replace an emissions controlled engine in CA, regardless of the status of the new engine.

Motorcycles (as the M3W is registered in California) are not subject to any type of emissions testing. Should you purchase a 124 inch, 128 inch or even a 138 inch motor, the state is not really concerned or able to determine that your M3W has been altered. I own several motorcycles and mods to them are not limited in anyway except for obnoxiously loud exhaust systems.

I'd be curious to know what variant of the 124 and more so what has been done to the rest of the driveline. While some feel the stock motor is lacking in power i don't think it's at all the weak link. Most versions of the 124 are at a safe minimum 50% more powerful in not closer to 100% based on configuration.

I'd think with some moderate fabbing skills you could get a motor to fit. My real interest would be what's been done to the compensator and how they're planting that power on a relatively narrow rear tire.

I already inadvertantly break the rear tire loose.

Sorry off the topic a little. Is there different engine options when you order a Morgan as I did not see that on the options list?

I think MMC have offered an unlisted performance 128 cu inch engine option in the past and may still do. Main difference is larger 4 3/8 inch bores.

having built a 128CI motor, there is extra power in the extra CI's (cams/58mm throttle body/roller rockers) but what you should do first that makes a real difference is to open the exhaust up, upgrade the air cleaner and replace the ECU with an S&S running file as the lock up Morgan ECU/File detunes the engine.

But I have to wonder if that is done to extend the longevity of the rest of the drivetrain?

The S&S website says otherwise regarding the legality of aftermarket engines, as do most of their resellers....

Looked up the CARB website, it looks like you're correct as per their FAQ:

https://www.dmv.ca.gov/portal/dmv/detail/vr/smogfaq

Dennis over at Morgan West had a prototype. Sadly I never got a chance to give it a go before they sold it