The 960 had an overhead (twin cam) 6 in it with rear wheel drive. They only came from the factory in NA form though. Probably the most obvious big power route to take is to take a Volvo 850T5R engine, stock in the region of 240bhp and will go considerably beyond.

They are a modular engine, ie the 5 pot out of the 850 is essentially the same as the 6 out of a RWD 960. You can therefore bolt a 960 RWD box onto it.

It is also less of a boat anchor than the B30 engine, but considerably more complex.

James,
The 1800-289 article states that;
"Neglecting the small friction losses in any gear train,output torque equals
engine torque times the lowest transmission ratio {first or reverse} times the
ring-and-pinion ratio. For a stock P 1800, this 110 ft./lbs. times 3.25 {reverse}
times 4.56 {or 4.10 without overdrive}. It comes out to 1600 ft./lbs.,and
spicer rates the 27 axle at 1800."
Of course overdrive and reverse are incompatable,and it is an early car with a 27.
It goes on to say;
"Firms like spicer tend to be very conservative when rating their products,so
they operate indefinately at rated load. Peak torque in a passenger car comes
only rarely and then only for a brief moment {brief but exhilarating}. It doesn't
take long to check all other uses of the 27 and find that it's used on the
Studebaker with V8 and automatic and that ratios up to 3.73 are offered.
The appropriate multiplication is 260 x 5.16 {at stall} x 3.73=5000ft/lbs.
Stude axles were never faulted {although it's worth noting that station
wagons,taxi's and police cars came with the larger 44 axle}. So pending
an unexpected misfortune,this volvo still has it's original axle fitted,of
course with a 3.07 ratio. {ratio swap was covered earlier in article}
If it should break,or if a limited-slip is called for,a 44 will be made up
with Volvo spring perches and hubs."

Note: A one piece drive shaft was used.

Soo if I may,let me pop some numbers in there even though
you have a 30 not a 27. Assuming 200 hp nets 220 ft./lbs,
and your M-41 1st gear is 3.13 + you did mention a 3.31 rear end?
220 ft./lbs. x 3.13-1st x {3.31 +11%} X for od=3.64 =2506 ft./lbs.
220 Ft./lbs. x 3.13-1st x 3.31 =2280 {usually no od on race cars}

It looks like you have PLENTY of tire and wheel there,and there are
guys on this board who have up to @ 200 hp coming out of the B 20.
The quality of the hardware is good,and keeping a Volvo a Volvo is
a statement into itself,however modified it is.
Example: 600 hp SEMA Amazon Wagon.

I guess that's as close to a recommendation as I can get.
Best wishes,It's a great looking Hot Rod,and a bold move.
Ken
--
White 86-245 DL, M 46, IPD bars & Wagon Overloads,Commando Bumpers,SS Belly Pan & Air Pickup,Straight-Shot EMT Chassis & Tower Braces,Scorpius Alloys,2 Belt No AC Conversion,Black POR-15 No Glare Front End

Some of the 900 series had a 6 cylinder OHC engine, but I believe they were
not as trouble-free as the B30 and a LOT more expensive to fix.

The megasquirt injection system would work on a B30 for a few hundred dollars
and is adaptable to any perf improvement. For stock, D-jet (like you have)
is probably OK

There are combinations of hubs and OEM Volvo wheels that fit - Much better
than redrilling, not to mention probably a lot safer too.

Where in Nord Dakota are you from?

Please give us some info on problems encountered in fitting the B30 into
the 1800!
--
George Downs Bartlesville, Heart of the USA!