30 replies to this topic

[Ethel]

You won't have gained 9 ponies from putting your car on the rollers. Any power increase will be from something the dyno guy altered, usually a bit of needle profiling and tweaking the overall advance. BL/Rover will have put far more than dyno time into developing the factory tune. It's best to be sure you are atleast starting from the correct factory settings, otherwise your gains are likely to come from compensating for loosely related faults and will have yet more knock on effects. Say your timing chain has stretched, better to replace it and regain the correct valve timing than turn the dizzy with the sole intention of getting peak power in the artificial operating conditions you get on a stationary rolling road.

 

Rolling roads can be useful, even if the engine hasn't changed, the petrol it runs on isn't the leaded stuff that was in the pumps when small bore A's were developed. They aren't a fix all panacea, that's all.

[Moggyton]

You won't have gained 9 ponies from putting your car on the rollers. Any power increase will be from something the dyno guy altered, usually a bit of needle profiling and tweaking the overall advance. BL/Rover will have put far more than dyno time into developing the factory tune. It's best to be sure you are atleast starting from the correct factory settings, otherwise your gains are likely to come from compensating for loosely related faults and will have yet more knock on effects. Say your timing chain has stretched, better to replace it and regain the correct valve timing than turn the dizzy with the sole intention of getting peak power in the artificial operating conditions you get on a stationary rolling road.
 
Rolling roads can be useful, even if the engine hasn't changed, the petrol it runs on isn't the leaded stuff that was in the pumps when small bore A's were developed. They aren't a fix all panacea, that's all.

Well yeah he obviously tweaked things. I didnt just mean it gained 9hp from running it on the rollers.

Edited by Moggyton, 14 August 2014 - 03:06 PM.

[blacktulip]

I say do as many free mods as you can then get down to a reputable rolling road. There are many ways to make it go faster for free.

[ShaunaFTW]

 

Maybe keep your existing set up and get it serviced and a tune up on a rolling road..... :0) it'll make a world of difference
Cheers james

Right, a few people have mentioned rolling roads to me now, I think I'll look into it, if I take it to a rolling road place im guessing they can improve the output for me there right? By doing whatever they think? I reckon I'll look into the costs of it.

Thanks.

 

 

Try http://www.hitechmot....uk/contact.htm :)
EDIT, found link!

Edited by ShaunaFTW, 14 August 2014 - 05:24 PM.

[Dan]

im just debating if id be better off covering the holes, and piping with duct right up behind the grill, so its just the coldest air possible being pushed through the filter box.

These things don't really work. At least not in a Mini. They appear to work in other cars because more modern machines have quite effectively sealed engine bays, often with a very inadequately sized air intake provided. The induction kit actually works simply by providing a larger opening in many cases, not because it provides cooler charge. In a Mini the engine bay has a massive open front like a basking shark's mouth. This is also why it's apocryphal that your pancake is taking in hot air. Testing has shown that above 9 - 12 mph the temperature of the air at the bulkhead is the same as outside and it's at a considerably higher pressure. The intake would have to be really close to the exhaust manifold to pick up any heat. The old Cooper air cleaner has the intake in possibly the only really bad position and it's not like the car performed badly as a result. The real disaster with those kits is that they use corrugated hose. This stuff is terrible for flow, the ridges create massive turbulence inside and the turbulence limits flow. The hoses flow only as well as as a smooth hose of 2/3 to 3/4 the size of the corrugated one. To make this work for real you need a solid walled, smooth, massive cross section duct from the grille to the carb mouth which needs to be properly gas flowed and nicely tapered. Some Miglias run such things but they take up a lot of space and cost a lot of cash for little real gain.

[Mrstars11]

im just debating if id be better off covering the holes, and piping with duct right up behind the grill, so its just the coldest air possible being pushed through the filter box.

These things don't really work. At least not in a Mini. They appear to work in other cars because more modern machines have quite effectively sealed engine bays, often with a very inadequately sized air intake provided. The induction kit actually works simply by providing a larger opening in many cases, not because it provides cooler charge. In a Mini the engine bay has a massive open front like a basking shark's mouth. This is also why it's apocryphal that your pancake is taking in hot air. Testing has shown that above 9 - 12 mph the temperature of the air at the bulkhead is the same as outside and it's at a considerably higher pressure. The intake would have to be really close to the exhaust manifold to pick up any heat. The old Cooper air cleaner has the intake in possibly the only really bad position and it's not like the car performed badly as a result. The real disaster with those kits is that they use corrugated hose. This stuff is terrible for flow, the ridges create massive turbulence inside and the turbulence limits flow. The hoses flow only as well as as a smooth hose of 2/3 to 3/4 the size of the corrugated one. To make this work for real you need a solid walled, smooth, massive cross section duct from the grille to the carb mouth which needs to be properly gas flowed and nicely tapered. Some Miglias run such things but they take up a lot of space and cost a lot of cash for little real gain.

So in theory, am I right in thinking id be better to use the filter box with element filter in and leave the holes bored in it. Just don't bother with the ducting.

[Ethel]

Yes,

 

I'm not sure if I owe Moggyton an apology, I didn't think that's what you meant even if I gave that impression. I was trying to emphasise that rolling roads are just diagnostic tools that can't produce the best results if you don't have the other stuff sorted beforehand. Unless something's been done that changes the fuelling and ignition requirements of the engine it's better to start elsewhere.

[Moggyton]

Yes,

 

I'm not sure if I owe Moggyton an apology, I didn't think that's what you meant even if I gave that impression. I was trying to emphasise that rolling roads are just diagnostic tools that can't produce the best results if you don't have the other stuff sorted beforehand. Unless something's been done that changes the fuelling and ignition requirements of the engine it's better to start elsewhere.

Of course you dont owe me an apology. And yes, he did quite a bit of needle profiling

[661]

Is it true to say that if you have a k&n cone on a hs4 then the stub is worth fitting?

[BronkoMini]

Is it true to say that if you have a k&n cone on a hs4 then the stub is worth fitting?

This is what I've got, what's this stub you talk about?

[timmy850]

The stub stack goes inside the filter, it improves the flow into the carb body. In the Yellow Vizard book the flow through the carb increases by 5-6%, which is a big improvements for such a small thing...

http://www.minispare...N etc/SS51.aspx

[BronkoMini]

Ah ok thanks

[Mrstars11]

Is it true to say that if you have a k&n cone on a hs4 then the stub is worth fitting?

i currently have this set up with the stub, and im swapping it this weekend to the original filter box with k&n element filter, and 6 holes drilled into the box.

ill report back if i notice any difference.

[Ethel]

Some filters have a stub stack built in. They're for the original style K&N's with sheet metal baseplates.

[coopdog]

Is it true to say that if you have a k&n cone on a hs4 then the stub is worth fitting?

i currently have this set up with the stub, and im swapping it this weekend to the original filter box with k&n element filter, and 6 holes drilled into the box.
ill report back if i notice any difference.

I bet that you don't :L

Just noise difference