Small, mid ,large valve engine

[Rough Edge racing]

 I hear talk of big and small valve engines used in Tonti frames. Also seems to be a mid sized valve heads. Some also have larger carburetors ?
   What year and what models use the various heads. heads?  Thanks

[PeteS]

I can only offer a few. The LMI, II, and III have medium valves. The LMV has large valves as does the first year 1000S. Mixed reviews on the large valve. Some say you give up low end for top end. T, T3 have small valves.

Pete

[jwinwi]

Beg, borrow, steal or in the worst case scenario buy a copy of  Guzziology.
This kind of info is why I say that Guzziology is both cheap and priceless.

[Rough Edge racing]

Beg, borrow, steal or in the worst case scenario buy a copy of  Guzziology.
This kind of info is why I say that Guzziology is both cheap and priceless.

Duh, I had a copy and included it with the sale of my Guzzi to a friend...I will take a look at it...

[guzzisteve]

1993 and up Cali had all mid-size
V11 Sports, 1100 Sports are bigger yet

[Turin]

Actually, the Valves on 1100 and V11 sports are ever so slightly smaller than the big valve heads.

[Murray]

Actually, the Valves on 1100 and V11 sports are ever so slightly smaller than the big valve heads.

WHS they reduced the valve size -5mm from memory as they were concerned the lift of the 1100 sport cams would cause them to interfere.

[Rough Edge racing]

 While on this topic, do the square fin heads fit on round cylinders? Or square fin cylinders fit on a block originally fitted with round fins?

[PeteS]

While on this topic, do the square fin heads fit on round cylinders? Or square fin cylinders fit on a block originally fitted with round fins?

The moved the studs out on the square fins to allow for the larger bore.

Pete

[Rough Edge racing]

The moved the studs out on the square fins to allow for the larger bore.

Pete

Ok,so if a person  is looking to do performance modifications, a square fin is the best option....

[guzzisteve]

Actually, the Valves on 1100 and V11 sports are ever so slightly smaller than the big valve heads.

Yes, can't remember crap anymore, and don't care to look nothing up, the new normal.

[PeteS]

Ok,so if a person  is looking to do performance modifications, a square fin is the best option....

Depends how big you want to go. I have a 992 kit for my 850. The block has to be bored out to accept the bigger spigots. If you want bigger without resorting to stroking the crank you want a square fin.

Pete

[jwinwi]

Ok,so if a person  is looking to do performance modifications, a square fin is the best option....

Yup. LM1000 or the rare as Rocking Horse Sh#* 1990 (?) Cal 3 with big valves and 40 mm Dellortos.

[Tom H]

Depends how big you want to go. I have a 992 kit for my 850. The block has to be bored out to accept the bigger spigots. If you want bigger without resorting to stroking the crank you want a square fin.

Pete

Or turn the spigots. Also if you can find it, there was a kit turned and ready to install.

Tom

[Rough Edge racing]

 I'm more interested in the heads than bigger engine cc's. The square fin has the option of bigger valves without using rare Lemans heads with their large combustion chambers or expensive head mods done by moody specialists.
  The raised intake ports on my 650 Triumph racer and the squish modification on the 79 750 Triumph says there's lots of improvement in throttle response, overall power and higher compression on available pump gas with old design hemi heads...

[PeteS]

Or turn the spigots. Also if you can find it, there was a kit turned and ready to install.

Tom

6 of one 1/2 dozen of the other. Just as easy to open the block and turn the spigots if you have the equipment. I did it myself on my mill.

There is a point where you just get an 1100 sport rather than spend the dollars tuning a smaller motor.

Pete

[Turin]

Any major gains are going to require one of the more serious camshafts, which requires re-working the heads. This is something I would farm out.