Well for about the price of getting a throttle body AND injectors (which won't do much for you w/o a specific tune), you can upgrade your pulley to 19% and get the GIAC and injectors. That'll give you about 3-15 times the power as the upgrades you're considering. (Here's the math: injectors by themselves give nothing and a throttle body will probably give 1-3hp. Switching to 19%, GIAC and injectors could add 15hp. But then again it's the torque that'll blow you away. )

 

I agree, people are spending waaaaaaaaaaaaaay too much money on throttle bodies and cold air intakes for little to NO gain.... changing the pulley and getting the a/f mixture fine tuned is worth the money spent. It's great to have the others but hp for $$ spent it isn't worth it.

 

i've been running 19% pulley(great) miltek header (a little fluff)
miltek cat-back (a little fluff) alta intake (fluff) but a great sound.
goining to giac tomorrow for their flash& installing 380 injectors
(no fluff ). thanks to all of you @ nam, i"ve been guided down
that road to complete joy from my s
doug

 

Outstanding data, JLM.

You have crystalized my uncertainty for how large to go with my current and planned mods. I didn't want to buy too small for my planned mods, nor too large where I'd have to do some radical tunning to keep them under control.

I took the plunge and bought some 380's from Helix. Wish I could send my ECU back to the states for the GIAC flash... but I'm overseas, no local GIAC tuners, and this is my daily driver. So, I hope to work with MTH to get the fuel maps dialed in. So far Franz has been very accomodating. I just received my widband O2 sensor and I hope my a/f guage will give me enough resolution to give Franz accurate feedback so he can create the maps.

JLM, didn't you post your perferred a/f ratio plot? If so, may I trouble you to repost or which thread was that in? If you don't mind, I'd like to use it as target goal. Thx!
ciao!

 

from last year

 

Ah...it's great to hear from the converted! Let us know what you think! Enjoy!

 

I've read the NAM posts and talked to Eric and to my local GIAC dealer and am strongly considering adding the 19%/GIAC/380's to my JCW-equipped MCS. Two years driving it and wanting more. I really like the sound of adding that low end torque.

 

went to saratoa yesterday for the above up-grades.
wooee,like a different car. more responce,faster out of the hole,
completly different car . it was i was driving a fine tuned rocket.
butt dyno say's doug did a good thing.don"t wait you-all go for it.
doug

 

EXACTLY! WIth the great takeoffs, fast throttle response - when you want it, and power from 1k to redline (no stumbling, bog or hesitation whatsoever at 1k RPMs and 5k RPMs up when those injectors come into play - HOLD ON! ) Glad to hear you like it!

 

Ok, decided to pull the trigger and get the 380cc injectors from Helix, going to send my ECU back to Ren-Tech so they can set it up with the new programing.

If that "damn MINI" dealer wouldn't of flashed my ECU, I'd have saved $400 and never did this...oh well, bigger, faster, stronger.

Plus, it was an excuse to do a mod without my wife throwing a fit, "honey, I had to do it, had to send the computer back to Florida anyway"

I'll post the results in a few weeks

Thanks to all for the insight

 

After a quick call to Classic MINI, I decided to go with the JCW 380cc injectors for almost the same price as the "off brand".

Should be here in two days and the service dept says it should only take about 1.5hrs of labor, so I'm guessing I can put them in in about 45min.

Again, I'll let everyone know how it comes out, plus I can get the M7 catch can with the $125 credit they give on injectors.

 

I am curious. I have been talking to Eric about injectors/19%/GIAC. I just put Randy's head on my car with a street cam. I called Eric and put the injectors on hold until I get a feel for what the head is doing for me. Given the Miltek header/catback, the WMS TB and the head and cam, if I stay 15% do you think I would benefit from the 380s?

 

It's very possible since you have all that other "stuff". Just make sure you have an ECU program for them. However, the move to the 19% from 15% will get you way more power than the injectors and at a fraction of the cost.

 

what about all the warnings of "not for the track" on the 19%. My occassional track days 3-4 per year.

 

Last year I ran at the Talladega Gran Prix track for a track day with the 19%. I artificially (when I had time to see it) set my red-line at about 6600 RPM.

Nary a problem.

I believe that if you simply want the most bang for the buck, the 19% has a HUGE advantage over the head and 15%. Not counting the massive cost delta.

My 19% has about 22k miles. As a matter of safety, I do change the belt about every 10K. Just changed it, in fact. It looked great, but the tensioner showed signs of some stretching.

I have the M7 injectors and I still have the Webb/Powerchip ecu.

Had it checked at the best dyno facility I know of in the Atlanta area. Didn't care so much about the power, wanted to know what the a/f ratios looked like.

If it looked bad, I was gonna sell the M7s and get the GIAC/Helix set-up. Still don't know if the safe area is adequate for sure.

The results looked good enough to me, but I'd be open to some expert opinion of the a/f.

 

Thanks Jim

 

Okay, I'm asking to learn here. I have neither opinions nor suggestions, just a question.

With today's modern and efficient engine management programs, why would overly large fuel injectors waste more fuel? I thought they could detect how rich they were running and lean the A/F mixture more. No? What am I missing?

I'm not talking about the possibility of wasted money on injectors you don't need. I'm talking only about unburned, or partially burned fuel. From some of these posts I'm getting an image of puddles of unburned gasoline if you go with the 440s and a 15%.

Hunter

 

If you're asking me, I'm no expert. But I have owned highly modified cars in the past, and the concern was always safe area.

I put in the M7 400cc injectors to provide less of a lean-out condition with the 19%. I had no interest in the larger injectors with the 15% I used the previous 20,000 miles. Unfortunately the penalty for being an early adopter means the GIAC/Helix 19% combo didn't become available until I already had mine done...

I don't mind the relatively slight penalty in fuel mileage. I do wonder if the GIAC/Helix combo would give at least the same performance - with a greater safety margin - averaging at least 12.5% a/f or richer...

Trouble is - I don't know how to know :(

 

when you are needing lots of gas, the larger injectors work fine and the ECU holds back the pulse width by servo-ing off the O2, MAP, throttle position. When you are WOT, the pulse width is set from a fixed look-up-chart with the data intended for smaller injectors, so you will be using more fuel, this may or may not be a bad thing depending on your motor.

where the larger injectors are in question is at idle and low speed running, where the fuel per pulse is too large to be controllable.

 

oh

thanks

this actually makes sense

Hunter

 

Ditto Thanks

 

Okay... you guys don't know who i am... so i don't expect many of you to believe what i am talking about... i am new to MINI's but i am not new to Tuning. I would just like to make a very samll comment regarding people quoting A/F ratios... yes to be at stoich is a good thing for Naturally aspirated engines... it is not something that you want to be at on a boosted engine...(especially here in AZ) boosted cars(especially turbo cars) should be run at lower than stoich ratios. 13.1:1 is too lean and i would personally never run my personal street car at this ratio. Here in AZ it is too hot and with 91 octane you are very likely to launch your motor due to the high temperatures. If you run race fuel, of at least 101 octane its a whole other story. I don't know everyones back ground on tuning and i don't want to jump to conclusion about other people but i would just hate to see some of you guys blow your engines because of a guy who read about stoich in a book or heard about it on HP TV and started his shop and started tuning cars. yes your car will live at 13.1:1 who knows for how long... it will run and probably run for quite some time until a very hot day or bad tank of gas or the computer one day makes up its own logic one day and boom. i would just tune my car to a safe level if i was using my street car with pump gas. Just my two cents guys... if anyone is curious of my background with cars i would be more than happy to fill everyone in... i just don't want to waste anyones time about my history or come across as bragging...


Anyways guys thanks for listening

 

ok, then what's your take on the 400cc, 380cc, 15%, 19% debate?

Logic and reasoning as to why one would be better or worse for the decision.

Personally, I'm with the 15%, went with the 380cc JCW injectors, having the ECU retuned by Ren-Tech to use the new parts. I'm just backyard mechanic and butt dyno kind of guy. I'm thinking this will squeeze a few more and give the the extra "burst" on WFO.

My .02, or $400 (since I did buy the injectors)

 

For clarification the stock injectors are running at 340cc and 80% duty cycle for a stock mini cooper s according to m7. If a 15% pulley is thrown into the mix that means the stock injectors will be running at about 92% duty cycle. I ran this by some experts at bullet performance shop in souther cali, the optimum range is around 80% duty cycle. If your injectors are running at lets say 92%, the injectors are pushing at near their max. One slight clog or something like that could cause the spray pattern to be altered. This then alters the cone spray of the injector which could lead to lower performance/ or even some serious engine issues.

With the jcw 380cc injectors this puts the level back around 82% duty cycle which is within safe margins.

Best case is to get a 15% pulley, get the jcw 380cc injectors, than if you dont want to pay much for a tune just go to your mini dealer and have them flash on the jcw ecu tune. I know this is not the best tune or even close, however it will be much safer than just slapping on your 15% pulley.


I know many have a 15% pulley on their car and have seen no issues ,however this will insure that your mini will be fine for thousands of miles to come with the new added performance.

 

Just a quick note: here in AZ we have 91 octane and we tune our cars with the AFR in the 11.0 to 11.5 range. Having anything in the 12.0 or 13.0 range is way too lean for forced induction cars.

I'm running my 06 MCS on E85 (roughly 100 octane) with Bosch 550cc injectors and my AFR is barely into the 12.0 range. My power is almost 250whp/198wtqe on a Mustang Dyno. Let me know if you have any more questions about your Mini.

Here is all the stuff i've done to my mini (read posts #1 to #10):
https://www.northamericanmotoring.co...-your-mcs.html

cheers.
mike