Tuning late model DBW cars
 

So I've been adding a few bolts ons since I had the car and I'm starting to get worried that the mods I've added are taking the car into the area of unsafe AFR.

Mods are: Mugen catback, Berk High Flow Cat, K&N FIPK but later changed to Mugen intake.

I had a dyno check done at the end of last year, at that time I had an AFR that between 6000 and 6500 rpm rose to about 14.2. Not that different to some of the other NA cars that tested at the same time and the AFR was otherwise in the 12-13 range.

Step forward to the dyno tests that I had done when I changed the exhaust manifold. The first tests before the manifold change showed AFR in the high 15s. Only mod change was the K&N intake was changed to Mugen. obviously testing equipment and conditions were vey different. I got a better plot with the Berk because it has the extra boss. The final AFR again showed a peak into the low 15s just at the point of vtec.

I don't have any experience tuning but I know that going too lean is a really bad thing. It raises a load of questsions and as I'm looking to get a new Manifold (Js or Toda) to replace the Berk, I don't want to put in a further mod that pushes it out the other side of silly. I've been reading up about these things and there are other reports of owners that have seen AFR heading into the 16s after they have fitted intake, manifold, decat and exhaust.

So in no particular order here are some of my confusions.

Most of the time the AFR is where it should be, for a second or few it goes too lean is this really a problem?

The stock ECU with its knock sensor should pull back if it sees anything going too wrong shouldn't it?

All the Dynos have been done open loop and WOT, does the same thing happen in vtec and closed loop?

I'm pretty sure I can be closed loop and vtec, because I have a scanguage and monitor throttle position and loop condition or am I really getting confused?

Should I stop wasting money on bits that don't make it any faster and put my OEM Cat and header back on the car?

How can I get the AFR back under control in a DBW - piggy back ECU?

Some owners have tried Dastek, I've read some less than glowing reports for Apexi VAFC2. What about HKS F-Con Greddy or others?

You don't have to many choices. You can get a hondata reflash or with there kpro. Or maybe a aem standalone. Apexi VAFC2 and most other piggy back ecus work off a 5 volt tps signal. DBW works with data lines witch are not compatible.

Forgot to mention that this is a European car. that means AP1, F20c, a different ECU and as such I don't think that a Reflash will work.

That's very interesting, dbw in an ap1. You should update the title. I'd email hondata to see what they'd say.

Hondata Kpro is the way to go

Greddy Emanage

http://www.holyrollerdyno.com/Holyroller_D..._Ultimate).html

It's been tried and failed. might work in the future but it's far from a tried and tested method. It's also a big old hammer to crack a smallish nut but would be good if I ever wanted to get blown...

My main aim from this is to get a little mid range improvement and keep everything in safe parameters, it's really just about getting the AFR under control.

:cool: Starts to look more like it. I've heard some mixed reports about Greddy and would need to see if anyone in the UK has experience tuning with one.

Greddy Emanage will work perfectly, however, few know how to property set it up.

What I linked you to is a pre-tuned unit featuring various maps for various modifications. It has a range of fuel settings (catalytic converter , test pipe) and a range of timing settings (mild, moderate, aggressive).

It also features o2 feedback such that you are always operating at an optimal AFR regardless of weather.

I just bought one for my brother's AP1 not too long ago.

Best of all, it is completely compatible with drive by wire F20c. The tuner who put this together has a few friends in Australia running this now.

The great thing about this kid is you don't need to go ahead and find a tuner. It is also a superior option to Hondata since there aren't different settings in the reflash for different mods. Also, Hondata doesn't feature closed loop feedback.

I'm a little confused, so you have a Berk's HFC or Berk's Exhaust Manifold or both?

Adding a Manifold/Header will only lean you out further. If you had a test pipe it would be even worse.

Also when your testing the A/F Ratio, are you doing it from the tailpipe? If so I believe it reads a little high compared to the header location (which is more true)