tuning tips for a cooper Sport (1999 model)
Discussion
have just taken in a lovely little cooper sport and having fun with it, so much fun I am tempted to make it go a bit quicker before selling it.
Are there any easy steps to get a bit more bhp out of it?
Anoyne done the same to a similar model?
its a standard Cooper Sport model, standard exhaust injection etc.
Are there any easy steps to get a bit more bhp out of it?
Anoyne done the same to a similar model?
its a standard Cooper Sport model, standard exhaust injection etc.
I'm assuming it's a multi-point injection car.
You can gain a noticeable improvement by just doing the following:
A gas-flowed head with a slightly increased comp ratio. You need the specific MPI head with your car as it's a different casting from all other Mini heads.
A set of 1.5:1 roller rockers,
LCB exhaust manifold and RC40 rear box
These are relatively cheap and easy to do.
You could get the ECU 'chipped', but it's expensive for the small gain in bhp you would get.
By the way, with offset rockers it can be a bit difficult to pass the current MoT emission test.
I hope this helps
You can gain a noticeable improvement by just doing the following:
A gas-flowed head with a slightly increased comp ratio. You need the specific MPI head with your car as it's a different casting from all other Mini heads.
A set of 1.5:1 roller rockers,
LCB exhaust manifold and RC40 rear box
These are relatively cheap and easy to do.
You could get the ECU 'chipped', but it's expensive for the small gain in bhp you would get.
By the way, with offset rockers it can be a bit difficult to pass the current MoT emission test.
I hope this helps
Cooperman - are you recommending 1.5:1 roller rockers?
rallycross, so far I've only got a 57i filter on mine. Sounds good (for short distances) and might free up a hp or two. I've got another cylinder head to port (fitting 35.5mm inlets, bullet nose guides), got another standard exhaust manifold to match to the head - I understand the standard manifold is quite efficient and you can get 'magic pipes' for the MPI, and am still looking for another inlet manifold to clean up and match. Oh, and I'm looking to modify two airboxes into one for a quieter but more efficient filtration system.
For a reasonable cost, don't go expecting 100bhp plus like on the carb cars, I would suggest! Research/asking lots of questions, shows it is possible but more difficult/expensive. 75bhp should be relatively easy to achieve
And watch out for emissions, which seems to be a problem on some MPi cars but not others! Cooperman, if using 1.5:1 rockers, do you think an adjustable fuel regulator would be the way ahead to get the fuelling/emissions sorted? And what CR do you suggest - 10.5:1? Would this require 98 octane petrol?
rallycross, so far I've only got a 57i filter on mine. Sounds good (for short distances) and might free up a hp or two. I've got another cylinder head to port (fitting 35.5mm inlets, bullet nose guides), got another standard exhaust manifold to match to the head - I understand the standard manifold is quite efficient and you can get 'magic pipes' for the MPI, and am still looking for another inlet manifold to clean up and match. Oh, and I'm looking to modify two airboxes into one for a quieter but more efficient filtration system.
For a reasonable cost, don't go expecting 100bhp plus like on the carb cars, I would suggest! Research/asking lots of questions, shows it is possible but more difficult/expensive. 75bhp should be relatively easy to achieve
And watch out for emissions, which seems to be a problem on some MPi cars but not others! Cooperman, if using 1.5:1 rockers, do you think an adjustable fuel regulator would be the way ahead to get the fuelling/emissions sorted? And what CR do you suggest - 10.5:1? Would this require 98 octane petrol?
Edited by Cooper1999 on Monday 12th May 13:27
I have found that 1.5 rockers really only start to give any measurable improvement over about 4500 - 5000 rpm when using a hot cam like a 286 or better. They may well give more improvement lower down with a milder cam as the 1.5's have the effect of simulating a steeper 'cam ramp angle'. On the hotter cams it seems as though all they do is to make for a more 'cammy' engine. This is certainly the case with my 1310 rally 'S' engine which seems to have gained 3+ bhp at 6300, but not gained anything below 5000 despite making it even more 'lumpy' below about 3000 when hot. However, roller rockers do reduce valve guide wear by eliminating side load on the valve stems.
With regard to fuel, at over 10.5 comp ratio you should probably use 97 octane or add an octane booster like Aldon 100+, although if you have a points type dizzy, an Aldon 'Red' unit would probably have the flexibility to cope with 95 octane. An electronic ECU may well mean you need 97, although I may be wrong and it may cope. The answer may be to 'suck it and see'. If it doesn't 'pink' with 95 octane at full throttle at, say, 3000 rpm, then it's almost certainly OK. If it does pink, then add a load of octane booster till it doesn't.
With regard to fuel, at over 10.5 comp ratio you should probably use 97 octane or add an octane booster like Aldon 100+, although if you have a points type dizzy, an Aldon 'Red' unit would probably have the flexibility to cope with 95 octane. An electronic ECU may well mean you need 97, although I may be wrong and it may cope. The answer may be to 'suck it and see'. If it doesn't 'pink' with 95 octane at full throttle at, say, 3000 rpm, then it's almost certainly OK. If it does pink, then add a load of octane booster till it doesn't.
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