7 replies to this topic

[tpg]

Hi can you help please. Long storey short, I have converted a Jet Black Mini 998cc to Look like a Cooper. I have put a Metro MG cam with a 4 Degree woodruff key timed to 106 Degrees BTDC. It has a 12G295 Cooper head, It has D-Top cooper pistons, 2 HS 2 Carbs with Rich needles and Blue springs, a Dissy D45 with blue points. When driven it pulls away well but during acceleration to build up speed or to change gear or stay in gear to go faster there is no power to accelerate hard. To go faster I come of the accelerator to build up speed slowly. I have tried to replicate cooper spec but cannot solve the power loss. I think it may be timing?? what are your thoughts and can you advise? many thanks

 

 

 

[mbolt998]

Just try advancing it a bit and see if it feels better. If you get pinking you've gone too far. What is the timing currently set to?

[cal844]

Where are you located? If in the UK, have a word with AC Dodd or someone with his training to optimise your car

[68+86auto]

To start you need to check the timing at various points throughout the rpm range.

[Spider]

The original and stock 998 distributor won't suit that spec of engine, you'll need to have it re-curved to suit.

[tpg]

Hi Spider, thanks for info. Could you elaborate on what I should need to do or use to get this engine running properly.
Thanks

[Ethel]

The older Haynes's had advance data for most engines. That'd give you a starting point if it's close to a stock 998 Cooper, but we don't have leaded petrol anymore even if it was identical.

 

A good starting point would be to measure what advance you are getting (vac disconnected) using a strobe & rev counter - you should need less if all your goodies are filling the cylinders better and the compression is higher.

[Spider]

Hi Spider, thanks for info. Could you elaborate on what I should need to do or use to get this engine running properly.
Thanks

 

This probably isn't helpful in answering you question here, but it does cover why you need advance, why all engine specs have different requirements and most importantly, the pitfalls of getting it wrong;-

 

https://www.theminif...d-distributors/