Just curious to see if there is anyone out there that is running JUN 272s on stock ecu. If so, how is your idle, driviablity, and powerband overall.........

 

It will never work. To get a smooth idle you will need a EMS of some sort that can control timing. Also You won't see a greater power gain with the JUN cams over he HKS unless you are running a larger turbo. A flash could possible work....maybe...not reccomended. Now with a larger turb such as a GT35R you will see anywhere from 20 to 50 WHP gain over teh HKS cams. (See AMS website). I will be using them in my AMS 35R or 37R build project while I'm in Iraq.


SGT Bare

 

I currently have a 35R with hks 280s just thought that I would get some opinions as far as usage with stock ecu.

 

Getting cams to idle is all about maintaining adequate airflow through your MAF.. It can work.. Heck early on most people told me I wouldn't be able to get 280 cams to idle well with a stock ECU and now its pretty common place..

 

I remember though days and now my 280s idle smooth from start to stop with partial throttle. Just have been debating on trying the jun 272s with stock ecu, however I do plan to go to a standalone in the future.

 

The lift etc is different on the JUN cams though. I am not arguing with someone with your well known understanding of EMS malibujack. I am just stating that everyone from AMS to JUN themselves states that a powerful EMS capable of managing the timing in depth will be required to get a "smooth" idle off these cams.

 

The problem is the MAF, not the ECU.. If you take the MAF out of the picture (either by clamping the idle frequency, or swapping to an aftermarket MAF) The car will idle smoothly (you will hear the lope from the cams, but it won't load up and want to stall)

Its not a timing issue, since the ECU is capable of doing it..

My guess is there are very few who have really commited themselves to trying it since most who make the step up to those cams, already have their heart set on an EMS..

In my State, on a daily driver, an EMS would never be an option...

 

apparently the Jun 272 arent suppose to be good idea... but the Jun 264's should be Much better

when i swap my cams i think i'm gonna swap to the Jun 264's

 

Why aren't the Jun 272's a good idea? AMS uses them and so will I be. They are some of the most powerful cams on the market. They are just geared more towards a "race" tuned motor.

MalibuJack you are correct as usual. I completely overlooked the MAF issue.

 

I would have gone with the jun 264s but I plan on building the motor up along with an ems in the next 6 months. Its just that I have the cams now and was debating about installing them now using just ecuflash. However, I have read and heard that its hard to get them to idle unless you have a standalone. I appreciate the input that Malbijack had stated!

 

How about doing a jun 264/272 setup using the stock MAF?

 

There is nothing really spectacular about the jun 272s .. the reason why most people has idle issues with these cams is the ramp rates are just freaking high ..
Jun only have a mild 10.7mm quoted lift .. but it's the duration at 1mm lift that makes this a monster versus the HKS 272s ..

MJ is right that there's really very little you can't do with the stock ECU versus an EMS .. the limitation is the MAF and the low vacuum pulses from the cams that MAY cause problems ..

280 was recommended to run with only EMS .. yet there's success stories
Revolvers are also supposed to be used with EMS .. yet I'm using them with stock ECU with no problems ..

 

Quote: either by clamping the idle frequency, or swapping to an aftermarket MAF

What aftermarket MAF is recommended?

Where can I get one?

thanks in advance!

 

I have been using a Ford Cobra sensor and a ProFlow Karmann Converter box, unfortunately the company is defunct and I have not gotten word when the new product will be released..

But there is INCREDIBLY GOOD NEWS since there is something much better..

Once everyone realizes they need to swap to a more stable MAF substitute, the ECU+ has a built in "MAF Translator" for the GM 3" (and I think 3.5") Sensor and GM AIT sensor.. So not only does it do top-notch logging, but solves a HUGE inherant shortcoming in making big power with the stock ECU..

There is also the MaftPro, however I don't know enough about it since I don't have one to evaluate, but I think the logging isn't quite up to par compared to its other features. Oh, the Maftpro is also capable of speed density in addition to a blowthrough MAF conversion, and there is another product thats called MAP-ECU which also does speed density, however knowing the inherant shortcomings of speed density, I'd recommend against using it on a daily driver.

The ECU+ Can clamp your idle frequency too.. Which means if your airflow jumps around and loads up the car.. you can clamp it at idle for whatever frequency works best.. Its nowhere near as expensive to use the ECU+ as it would be to use a few different products.. Plus I have direct communication with the Owner of the company and developer of the hardware/software, so the Evo community benefits from suggestions since he's THE MOST RESPONSIVE to input than any company I have ever dealt with. And the product has even more cool features in the works.

 

Really? Where are you? I want to see this.

d