According the website MarineDieselDirect http://www.marinedieseldirect.com/universal/200157/universal-owners-manu...

UNIVERSAL MODEL M-35 SPECIFICATIONS
Horsepower30 @ 3200
No. of Cylinders4
Bore x Stroke2.96 x 2.76
Cubic Inch75.5
Maximum RPM3200
Cruising Range (Approx.)2100-2600 RPM
Compression Ratio21:1
Lubrication (Eng. Approx. Ots.)4.5 to 5.0
(Type AFT �A� or GM-DEXRON - II Do not mix different oils)
Transmission Reduction2:1
Coolant FWC (50/50 Solution Approx.)5 Quarts
Exhaust Flange1 �� N.RT.
Fuel Type#2 Diesel
Fuel FilterP/N 298854
Oil FilterP/N 300209
Eng. Operating Temp. Degrees F.165�to 195�
Propeller RotationRight Hand
Weight (lbs.)335 lbs.
Injection NozzleP/N 299517 & 299518
Engine is governor controlled to prevent overspeed. It is recommended to carry the following extra parts should the need arise: V-Belt, Sea Water Pump Impeller, Fuel & Lube Oil Filters, 1 Qt. of Trans. Oil, 2 Ots. Lub. Oil and 1 Gal. 50/50 Coolant.  All pictorial views and specifications subject to change without notice.

The M-35B had increased to 35 HP at 3000 RPM.

https://www.westerbeke.com/universalengines.htm
 

The universal M35b specs show a Max RPM of 3000 given that the correct propeller is used. Our 1998 M35b currently tops out at 2800 RPM. It has the factory installed 3 Blade propeller. Many vessels apparently had original 2 blade props, So I think that the question should be: What is your top RPM and what type of propeller do you have? Also the RPM guages are not always calibrated correctly at the factory (said my mechanic). so he calibrated our guage to read 2800 at full throttle. 

It's easy to calibrate the tach. Just a small screwdriver adjustment in the back of the tach.  I believe an optical tach is available to members to borrow. I bought a cheep Harbor Freight unit.  I did paint my front pulley flat black to get better readings.  Be sure and check at several RPM's. My tach is so old the adjustment pot in the tach is flakey so I use my I70 to display engine vitals.