Tuning an O type 1.7 engine

[mikeyp]

Hi there,
I'm new to the whole forum thing - so here goes.

I have recently joined MOC in preparation for a rebuild of my Marlin which last ran on the road some 15 or more years ago. It is a LWB Marina Ital version that I completed in 1992 in a joint build with Monty Watkins (a name from the Kit car past some of you may remember). A the time the first decent donor car we found was a 1.7 Ital, and we often lamented it's apparent lack of tuning options. In trawling through the Marlin technical tips recently I spotted a note from Paul Sandford on this matter and wondered if anyone has any further details about it?

Mike

[lil_red_roadster]

Re: Tuning an O type 1.7 engine

Little available off the shelf but a few ideas to consider...
- 2.0 MG Montego/Maestro is an O series, albeit what was known as an O2, in that BL changed the head (and oil/water ways) around so the inlet/exhaust would be on the offside when in RWD form...but they came with fuel injection and can with effort be mated to a type 9 or similar gearbox
- I believe Peter Burgess has some form with tuning the O series heads
- The 1.7 & 2.0 engines are very similar...same block, bore & head only crank & rods differ IIRC
- SD1 2.0 (a rare beast) came with twin SU if you can find one...and it is the O1 engine, so same basic layout as the Ital
- Princess also used 1.7 & 2.0 O1 series engines...some 2.0 with twin SU..?
- Sherpa Vans came with both O1 & O2 engines at various points albeit possibly in a low compression form (not sure on that)
- Rover M/T series engines (220,420,820) are essentially an O2 block with 16v head
- Megasquirt the 1.7...could be a fun project..!
- MX5 engine & box...and I've seen somewhere one of these running twin SU on a custom manifold (not in a Marlin though)
- Stick a Pinto in it :-)

PS - here's a brand new 2.0 short motor

[listerjp2]

Re: Tuning an O type 1.7 engine

I have been told they also turbo charged them.

adrian

Little available off the shelf but a few ideas to consider...
- 2.0 MG Montego/Maestro is an O series, albeit what was known as an O2, in that BL changed the head (and oil/water ways) around so the inlet/exhaust would be on the offside when in RWD form...but they came with fuel injection and can with effort be mated to a type 9 or similar gearbox
- I believe Peter Burgess has some form with tuning the O series heads
- The 1.7 & 2.0 engines are very similar...same block, bore & head only crank & rods differ IIRC
- SD1 2.0 (a rare beast) came with twin SU if you can find one...and it is the O1 engine, so same basic layout as the Ital
- Princess also used 1.7 & 2.0 O1 series engines...some 2.0 with twin SU..?
- Sherpa Vans came with both O1 & O2 engines at various points albeit possibly in a low compression form (not sure on that)
- Rover M/T series engines (220,420,820) are essentially an O2 block with 16v head
- Megasquirt the 1.7...could be a fun project..!
- MX5 engine & box...and I've seen somewhere one of these running twin SU on a custom manifold (not in a Marlin though)
- Stick a Pinto in it :-)

PS - here's a brand new 2.0 short motor

[mikeyp]

Re: Tuning an O type 1.7 engine

Thanks very much for the info - lots to think about, its nice to ponder while working on getting it rolling again

[dogoncrazy]

Re: Tuning an O type 1.7 engine

A member by the name of Paul Sandford wrote an article in Pitstop October 92 whereby he modded the intake manifold to take weber 45's , different cam , valves etc. Said to be producing 115 BHP. All in the archives. May be of some help.

[mikeyp]

Re: Tuning an O type 1.7 engine

Thank you very much - I will dig around in the archive