Is there a somewhat quiet exhaust available to allow runnining a stage two Accessport map?

 

No there is not. The down pipe needs to be changed to allow for the stage 2 or 3 maps to be used. Even with the second cat removed from the mid pipe you will not be flowing enough exhaust to use the stage 2 map safely.

Stage 2 and up requires a 3" high flow catted or 2.5" catless downpipe. A larger FMIC and better flowing intake should also be used as well.

 

Looks like I only need the Akrapovic high flow dp with my JCW exhaust for AP stage 2 ...perfect

Pasted from the other AP thread:


I am running the FMIC Stage I map now and it's no slouch but I think there could be more on the table. The Akrapovic downpipe has a high flow cat and the JCW exhaust only has a resonator. There is no catalyst. I may try the stage II map and see how the car feels.


Mike's response
"Yeah, your not making the most of the parts you have with the stage 1 map. The stage 2 should be adequate to handle what you have done. "

 

The only one is a I have seen that can do it all I can't even remember the name but its bad!!! Its about 4 grand built for mini cooper and its got a vanos hangin on the back thats hooked up to what is basicly a baffle. Its called variable tuned exhaust and it will go from quite stock to opened up on the flick of a switch or set up with the gas pedal.

 

Last week I inquired with Alta re: the AP through their online chat tool. The rep stated that although the JCW exhaust doesn't have a secondary cat, it's still considered stage 1 since the piping has the same diameter as the S exhaust. The rep indicated that an aftermarket exhaust with larger piping is definitely required for stage 2.

 

for all the trouble of changing exhaust ( I like the JCW exhaust and I have the JCW tips too!) I wonder if its going to make that much difference? I will have the Helix IC so I will be running the map; stage 1, 92+ oct , DOS intake,with a big IC.

 

Its ok, but notice I said adequate. This is not the best solution for power or safety.

Your best results for power and safety will come from using the parts Alta has stated to use.

- 3" hiflow catted or 2.5" cattless downpipe
- Larger FMIC
- Upgraded intake filter
- 2.5" or greater cat back/downpipe back

Now in terms of those 4 things, the first 3 are essential really. A significant sacrifice in power, safety or both will occur by not using one or more with the stage 2 and up maps. I'm pretty sure reps at Alta would agree with that as well.

The part that gets a little grey is the absolute need to run a 2.5" exhaust. Best performance will be found using at least a 2.5" exhaust. However forgoing that option for say JCW exhaust is not as detrimental as not doing the other 3 suggested items. Yes it may lose some power and you really should try to use at least 2.5", but this is often over shadowed by a persons preference in tone, pitch, drone, and looks. These can play such a huge part in a person's choice of muffler, that I've become little more reluctant in saying that a 2.5" exhaust is absolute. Basically what I'm saying is the gain from the exhaust alone is so slight in comparison to the other parts, that you don't need to sacrifice your ears to enjoy your car.

 

I just thought of this , I'll get a custom map made, a stage 1.5!

 

If you want a quiet exhaust then stick with stock, There is no aftermarket company that makes and exhaust that quiet. There are some that make exhaust that don't drone a lot but are loud when you get on it. Then there are the ones that drone and are loud as hell all the time. No loud=no aftermarket exhaust.

 

Even with the "small" JCW cat back and a catless downpipe my exhaust is pretty loud on the gas. But it is near stock sound levels at constant speeds and no drone. I just put the JCW Stage 2 tune on last week and had one occuance of the car pulling boost during a wot run through the top end. No other occurances, but that one was enough to make me go looking for a custom tune. The tune will be less cost than a replacement cat back and I only want to optimize what I have. I was thinking more along the lines of Stage 1.8 though.

 

https://www.northamericanmotoring.co...your-mini.html

 

When dealing with exhaust manufacturers there generally is a hefty price difference between 2.5" and 3". Since 3" border lines on the edge of overkill for our cars I'd suggest pushing for a 2.5" to bring the cost down. Even if it's a good company and the exhaust is quieter then most, your gonna have a hard time getting people interested if the price is not under 1k.

 

Miltek is quiet, thats what they go for. Even on WOT its not considered LOUD really... its audible obviously, but not raspy or obnoxious like an aftermarket is.

That being said, it may be due to restrictive resonators of packed mufflers.

Many people do like them though (more outside MINI, as not many people on the boards have one afaik).