Tuning Tuning a 650

[dangfiat]

Hi All,

I've just bought myself a 1967 500F (yay!) to keep my '66 Riley Elf company - apparently I'm an automotive minimalist!!

It's still on the truck, but it does have a stock Polish 650 already installed. I'm starting to look at options for what I can do to hop the motor up a bit. Nothing too overboard, looking at 595ss or 695 type performance (about 40hp?)

A couple of questions:
1. Head: Which head is best? What mods do people typically do (valves, porting, etc)? Is there a vendor that sells modified heads?
2. Carb: Read through a million posts, still somewhat confused as to which carb is best for a hot(ish) 650-700
3. Compression ratio? I'm in California, so figure to shoot for 9.5:1 or so
4. Cam: I see a few profiles (80/40, 75/35, etc). Which is best for a tractable street car

I've looked through the forums and am starting to get an idea of what to do, but would be very grateful if the knowledgable folks here could weigh in!

Many thanks
Daniel

also: here's a pic of my car! So excited! Looking forward to joining the community

 

[the hobbler]

Hi All,

I've just bought myself a 1967 500F (yay!) to keep my '66 Riley Elf company - apparently I'm an automotive minimalist!!

It's still on the truck, but it does have a stock Polish 650 already installed. I'm starting to look at options for what I can do to hop the motor up a bit. Nothing too overboard, looking at 595ss or 695 type performance (about 40hp?)

A couple of questions:
1. Head: Which head is best? What mods do people typically do (valves, porting, etc)? Is there a vendor that sells modified heads?
2. Carb: Read through a million posts, still somewhat confused as to which carb is best for a hot(ish) 650-700
3. Compression ratio? I'm in California, so figure to shoot for 9.5:1 or so
4. Cam: I see a few profiles (80/40, 75/35, etc). Which is best for a tractable street car

I've looked through the forums and am starting to get an idea of what to do, but would be very grateful if the knowledgable folks here could weigh in!

Many thanks
Daniel

also: here's a pic of my car! So excited! Looking forward to joining the community

Nice looking car! I see that some former owner has already fitted '126' hubs to the car. If you would like to contact me direct ( [email protected] ) I will send you a copy of my thoughts about tuning the 652cc engine and a '695' engine. My thoughts will answer ALL your questions. I have a fairly well tuned '659cc' engine (652cc + 0.4mm) in the backof my 500---28bhp at the wheels which equates tp 33bhp at the flywheel. Only the Factory '695SS' surpased this figure, so don't set your hopes too high.

 

[dangfiat]

Thanks for the response! I'll send you an email. the 33bhp sounds about what I'm going for (not trying to make a race car, just trying to make a reasonable daily driver for these California roads)

Couple of quick questions:
1. 126 Hubs? Are these at a different bolt diameter to fit different wheels? Eventually I might want to look for classic Abarth style wheels. Guess I'll have to switch the hubs back
2. Do you use an oil cooler? A bit worried about the 100F (38c) summer days here. Thinking of putting one on a thermostat

Many thanks, going to be a fun little car

Daniel