Hello,

I have an 04 JCW and I am about to begin to add to it in the go fast department. My budget right now is about $2000 and from what I have been reading here on the message boards, have come up with this list.

1) Alta Header w/cat
2) Alta Intercooler Air Diverter
3) M7 AGS V2 Pro
4) JCW injectors???

Not completely sure about the last one though. I am sure with "hopefully" more air coming in I will eventually need an upgrade in the fuel department. And to accompany all of this, an ECU tune (MTH) would be in order shortly after all of this goes on.

So from the experts on this board, does this sound like a good upgrade path?

Thank you,
JBravoMC

 

I think your list looks pretty sound. If I were you, these are the mods i would do, in order of importance.

1) ECU Remap (MTH or wateva)
2) M7 AGS
3) Headers (alta looks fine)
4) Injectors

I don't know about the Alta diverter for the works kit. ( i have one, and it does make a difference, but i have a 17% pulley, so i don't know if your car needs one).

Apparently the MTH software makes the JCW car a lot better.

 

DO A PULLEY!!!! I saw a direct comparison of stock JCW and 15% pulleys the differance is almost unbelieveable. then ECU, header and brakes. You should have CAI if one didn't come with your JCW, then AGS,ALTA or HDI. Brakes are where the MCS is most lacking so Id make sure that was the fisrt thing done.

 

Get a better hood scoop. This will improve IC operation. If you're still on stock brakes, get the metal caliper bushings, some better pads and some better fluid. If you haven't done anything for handling yet, get a rear bar. Control and braking before power.....

The JCW has about a 14% pulley on it now. If you don't an intake, that's a good way to go. The AGS is good, but it ain't cheap. If you really want to save some pennies, just go for the Hot Air Intake (under $50 installed!). I don't know if the 04 JCW has the stock exhaust or the JCW one. If it's the stock exhaust, get a one-ball mod. It and the header are a nice combo.

Another approach would be to take all that cash, and put on a good head. When you have some more, get an ECU tune and some of the other stuff.

No matter what, you'll have some fun. The head willl unlock the most power of any of the mods listed. And as you add things like a header or a tune, the car will really dance!

Matt

 

We decided that the best area to measure was around the pulley where the belt sits, rather than just the diameter of the face. Here are the stats:

Stock Pulley = 8" 5/16
JCW Pulley = 7" 7/16
15% Pulley = 7" 3/16

If the math was done correctly, I think that makes the JCW an 11% reduction and the 15% a 13.8% reduction.

Heres the hard #s

 

Andy has posted some real numbers using the reccomended diamter changes based on the belt we use (from the Bosch handbook). They're out there somewhere.....

Matt

 

If you can find the "real" #s and exactly how they were calcutaled I'd be real interested to hear them, these were measurements taken by a MINI tech.
According to these #s
15% pulley is 86.466% of original
JCW pulley is 89.473% of original

 

It's the pully diameter and the belt. And when the belt bends, there is compression on the inside, and some stretching on the outside. So the effective diameter is actually larger than the pulley itself.

Matt

 

So are you also implying non linear belt bending?

Edit: just to be clear I'm trying to learn more not challenge you.

 

One side is ribbed, and one side isn't. Also, it's a layered construction...

Matt

 

Right but, if 13.5% reduction in the size of the pulley caues a 15% reduction in the belt, then I'd be inclined to believe a 10.5% recduction would cause the belt to reduce to 12% not 14%.

 

https://www.northamericanmotoring.co...5&postcount=17

https://www.northamericanmotoring.co...5&postcount=19

The thread has lots of other references....

Matt

 

I started this thread because we've crossed from discusing a possible mod to analyzing parts.

 

with a power budget of $2k, I vote for a head. All the little things discussed will eat up your budget, and net less power. When you do add more stuff, the head will really let the benefits be felt.

Webb makes a head that includes a cam for about $1800.
Pilo offers various levels of heads, but some exceed you budget.
M7 has the Cosworth heads, but they are a bit more expensive than your budget too.

Matt

 

Wow, thanks for the replies.

So maybe a little background on the car. From what I know, my JCW does not have the injectors as it was done pre 05. I do currently have the K&N Typhoon but thought the AGS appears to be quite a lot better than other intakes as it seems to have removed that nice crimp in the stock air intake tube after throttle body. I also woudl be getting the pro with the larger throttle body.

My car does have the JCW exhaust already and the headers seemed like a no brainer to me. They did wonders for my old M3 I used to have.

Not sure about a new pulley. would going from ~14% to saya 17% really make that much of a difference?

My real questions I guess then goes to the good Doctor. Do you really recommend a new hood scoop rather than the air diverter? Maybe because with the better scoop you are cooling the entire engine bay a bit more?

Also, my JCW already has the JCW head, are the others really that much better? I was recently reading a thread regarding the JCW head and the others but no one had an real hard numbers that I remember seeing.

Brakes and suspension are coming soon too. brakes will be getting the metal bushings and new pads. (read your article in MC2. ) Then suspension will more than likely consist of new rear sway and the Koni Sport kit. Thought about coilovers but don't really need all that adjustibility for street wit the occasional 1-2 per year auto-X.

Thanks agian for everyone's input.

 

I know someone who wneth from a JCW Pulley to a 15% (Which is were we got the measurements for the tangent) and he noticed a huge diffeance.

Why not upgrade the IC, There seems to be companies coming out with front mount ICs which are the most efficent because the most air comes across the front and the the hood scoop cools the engine bay. Even just a more efficent IC with similar volume would yeild a significant change.

 

Alta has a flow through IC that's in prototype stage, and it works better than stock and better than the other TMICs I've tested. It doesn't come with a scoop (that I know of).

M7 has a new flow through design released, it includes the scoop, but I haven't tested it yet. Initial reports are encouraging though.

Either of these will eat close to half your budget.

The AGS does flow better than some other CAIs, but the benefit of the larger TB won't really be felt until you open up the rest of the motor.

The JCW head just has some of the ports cleaned up a bit, and not that well. It's not a full port/polish, and a good head will out flow it hands down.

First off, make a target for what you want out of your motor. Power, RPM range etc. Then build the list of items it will take to get there, and your prefered path (Nitrous is a huge gain, but not many want to run it!). Then buy parts that get you there as your budget allows.

Depending on your goal, you may run into injector limits, and the need for an ECU update. But because of how speed/density systems work (have to wait for the next issue of MC Squared! ), anything before the intake will be handled by the computer as it is now, although there may be some more power left to be had with a tune.

But I digress.... once you have your shopping list, start buying, but keep in mind that it's easier to add less expensive things as you go, and getting the high $ stuff when budget allows may be the only way to ever get them!

Matt

 

Also, From those i have talked to, the the Ram Air from M7 works best with the alta air diverter, that way you do not have to trim anything from the Ram Air.

 

Thanks to everyone for their posts.

I will eventually someday get to a new IC. From the sounds of it, the M7 for a TMIC would be the way to go right now. However, I want to keep it at least looking somewhat stock as I still have about another year or so on my warranty. I know some of these things might void it, but they are mostly hidden and hopefully I won't have to worry about bringing it in for any major work.

I think I am going to go with the following:
1) Alta Header w/cat
2) Alta Intercooler Air Diverter
3) M7 AGS V2 Pro (Love the audio clip I heard from this thing.)
4) M7 Ram air scoop in place of the JCW injectors. (Looks good and is functional.)

Thank you again for all the help. It will be another month or so before I get all of this and put it on, but I will definately post my butt dyno results.

Thanks again,
JBravoMC

 

Bravo, before you go spending money on the headers, read here https://www.northamericanmotoring.co...ad.php?t=55669

Especially read Spider's commentary since he has pretty much done it all ... Matts points on the head is what is important.

Basically, I am in the same situation as you except for the CAI and I have a different exhaust (forgetting about the brakes/suspension parts). If you read that thread, your going to see a consensus that (except for the CAI) bolting on headers, TBs, etc aint going to do much of anything with a real head and cam (which means new software). Only then will you see real benefits ... I was trying to learn from the people who had "been there, done that".

I also talked to our local MINI racing shop and they confirm wholeheartedly to forget about headers, TBs, ICs, etc as incrementally you will gain little. Its only after the head work is done that it all comes together.

Just some food for thought. Personally I'd save the $2K, add another K to that until warranty is over, then do the whole thing at once (except for the AGS).

 

Thanks for the link and recommendations Chow. One question though, why did you say (except for the AGS?)

Thank you,
JBravoMC

 

UR Welcome

I said except for the AGS because you dont have a CAI like the JCW airbox. A CAI is a part of that "first tier of mods", the simple bolt-on stuff everyone does.

In other words, go ahead with the AGS because you will gain a few HP. Thats cool. On the other hand, adding headers, even with the JCW head, will not get you the "advertised HP benefit" because the engine can't use it effectively yet so you might be disappointed, as others have been, in spending a lot of money without doing the most important part.

BTW, there is another thread around showing why the JCW head is poorly done ... compared to a true port and polished head.

Good luck!

 

Hey, this is some really good info.

I think I am going to wait a little bit, stretch the budget, and do the whole thing together including a new head and SW.

Now, which head?

I saw the thread on the JCW head and will begin to do my research on them now as well.

Thanks again to you and the good doctor for all the sound advice.

 

I'm about to pull the trigger for a head.
Would like more information/feedback about the Cosworth head -

 

he'll talk to you about it. He's also got some reference customers that have some bangin' cars! One had no problem pulling away from me at AMVIV! I'm sure there are others out in NAM land who can speak to it as well....

Matt