Testing of the JCW Exhaust and Intake on ALTA's GP!

We’re at it again proving more ALTA PARTS!  One question we always wanted to answer was “Do the ALTA parts make more HP than the JCW parts?”.  We get asked this a lot as customers are torn between parts they can get at the dealer, and aftermarket parts from us.  Our selling points used to revolve around the prices of JCW parts vs. ALTA.  Now we have another angle!  We can now say ALTA parts WILL make more power than the JCW, at a fraction of the cost.  What more can you ask for!

The car we started with was a newly purchased 2006 Mini Cooper S w/ JCW GP package.  For those that do not know, this is highest rated HP of any Mini Cooper produced to date (214hp and 184ft-lbs). While this a rare car, (only 415 were allocated to the US) we still had plans to modify it, and make it better.

First off a little history of Mini S’s on our dyno.  With a 15% pulley, intake, and catback we would see around 190-195WHP.  This is very typical and we have seen with many other Mini S’s.  The GP’s averaged runs were under 180WHP, and while these are the highest rated HP Mini’s ever made, the 180 is pretty close to what we would expect it to make (using a 15% drivetrain loss, and 215 engine HP).  So naturally getting to that HP should be easy (even with the GP’s bigger than 15% pulley) with our intake and catback installed.  

The first step in our quest to prove we make more power is installing the Intake hose.  We see about 5whp on regular Mini S’s with 15% pulleys, so I would expect similar on the JCW/GP packages.  Sure enough it was pretty close to that.  The gains with this part were at the upper RPMs where the stock hose becomes a restriction.

 
With 4whp gained from just the hose, things were looking good!  Now for the part that we have all wondered about making more power than the ALTA Intake. The JCW intake!  For those who do not know, the JCW intake uses a slightly different air box than the normal Cooper S.  2 things make it very different, one it uses a cone type filter (although still paper??) and it has a vacuum actuated flap at the back to allow more air to get into the box. The flap is a good way to add power, and not add noise.  While the ALTA intake definitely adds some cool Supercharger Wine to you car, the customers that want to keep it quiet may stick with the JCW just for that reason. But we now have another reason or two to buy ours over the JCW.

Reason number one.  Cost!  The JCW intake system costs well over $400 where as the ALTA intake costs about $260.  While more money means more POWER/better materials/cooler looks, in this case, we can prove that 2 of those features don’t work.  Which leads to reason number two, More POWER! While the results are not the 12-15WHP we see on a stock Mini Cooper S, the 7WHP, and 6ft-lbs of torque is definitely a repeatable and accurate gain over the JCW intake system.  Also this makes me wonder what kind of power the JCW intake makes on over the stock Air box on a Cooper S??  Hmmmmm…………….

 

So far we are on a high with our gains over the JCW intake system!  Next up is another JCW part people buy before they buy our part. The Catback exhaust!!  Looking at the exhaust there are a few things to take note of.  It uses 2.25” diameter tubing, and were it splits into 2 mufflers it goes to 1.3” tubing.  The ALTA exhaust uses 2.5” plumbing through out with no split.  So bigger should make more power??  The weight of the JCW system was 40.8lbs, were as the ALTA system is 28.0 lbs. So our save a bit of weight over the JCW, which you would expect with the single sided system.  So onto the dyno test.  This test was also done back to back, and the car was left on the dyno between run sets.

 

So while 5WHP and 5ft-lbs isn’t a huge gain, it is more HP than the JCW system, which is supposed to be an upgrade from stock.  We see about 12WHP on a 15% pulley car, going to our 2.5” exhaust, so we can conclude that the JCW exhaust might make about 6-7WHP. The exhaust system prices online vary quiet a bit anywhere from $1000 to $800, where ours is $300-$100 less expensive.  From this testing of the catback exhausts, we now have 3 things that make our system better than the JCW. Cost, weight, and HP!

 

This is the final gain we saw with replacing the JCW intake and catback, with an ALTA cold air intake, and catback exhaust.  If you are trying to eek out that last bit of power from your JCW packaged car, here is an easy way to get 10WHP.  Also if you are thinking of buying JCW parts vs. the ALTA parts, you will see about 10WHP and 10ft-lbs more torque along with seeing more money in your pocket, from overall part costs, and shipping costs.

We have a few more tests we will be doing with our GP in the upcoming weeks, one of those is the ALTA PnP ECU! Be on the look out!!