Argray Single Tip Issue

[Dragon]

I have a 2006 N/A Exige and installed the Argray single tip exhaust earlier this week. Everything else engine wise is stock. When I shift from 1st -2nd -3rd gears at light to medium throttle I get a nice pop. I noticed tonight there is a nice flash behind the car when it does this so it's definitely a small fire ball. It's kind of cool, but not all the time, especially when the PoPo is around. I'm sure it's over fueling during decel fuel cut. Is this common with the Argray and less back pressure on the engine or do I have anouther issue I need to look in to. The car also feels like it goes kind of flat on power from around 5k-6200rpm cam change over then it takes off again. It did this with the stock exhaust as well in fact it was a little worse and some times is actually stuttered like it was going way rich. I have no Cells. The first thing I checked was the air filter and it looks pretty clean and unrestricted. The car only has 7,000 km's on it. I have a scan tool on the way, but not sure this will help me much since there are no cells and I'm not sure how much data it will allow me to see and log. Also would like to note that actual engine braking decel is pretty smooth and I'm not getting the lean burn popping that others decribe.

So, the question is. Is this normal, a common problem or is there something simple wrong that won't throw up a cell.

PS. I've built many engines and have LOTS of tuning experience with Power FC datalogit, Motec and Microtec. I also have many certifications with ASE. So feel free to get as technical as you want.

[shay2nak]

the dip in power you feel from 5-6.2k is probably from the dip in torque in that range. There's a loss in torque before you hit the 2nd cam. So I'd say that's normal. I'm surprised you're getting fire bursts from your exhaust with a stock cat. I've got a 2bular straight pipe exhaust with a stock cat and I haven't gotten any. Just a lot of popping, burbling, etc. oh, this is on an Exige S, btw. Everytime I see a popo, I either drop it in neutral or take it up to higher gears and just go easy on the throttle.

[qball]

You said PoPo!

[Dragon]

Originally Posted by shay2nak

the dip in power you feel from 5-6.2k is probably from the dip in torque in that range. There's a loss in torque before you hit the 2nd cam. So I'd say that's normal. I'm surprised you're getting fire bursts from your exhaust with a stock cat. I've got a 2bular straight pipe exhaust with a stock cat and I haven't gotten any. Just a lot of popping, burbling, etc. oh, this is on an Exige S, btw. Everytime I see a popo, I either drop it in neutral or take it up to higher gears and just go easy on the throttle.

I can understand that it's running out of breath on the mild cam at those rpm's and the power/torque will fall off. In this case it actually bogs down and feels like the power drops off completely. I.e. too rich or lean, hard to tell with out a wideband hooked up. It could be retarding the timing as well due to a sensor input. Many engines will retard timing and add fuel if the engine is running too hot, intake air temps get too hot etc. The less back pressure from the single tip exhaust actually made this area better, though it still seems off. Then there is the fire/popping issue during every shift in the lower gears since the exhaust was installed. I'm still not familiar with this engine and its systems yet as I've only had the car for a couple weeks now. The fact that this is a fly by wire model doesn't help either. Is there any software out there that will allow me to plug in to the OBD2 port and retune/data log? Also are there any sensors that could be feeding the computer false data that would not throw up a cell and cause these issues?

Thanks...

[Dragon]

Originally Posted by qball

You said PoPo!

lol, I have a teenage son

[ducatiexigeowner]

Remove the cat.
Guess only a few of us notice how restricted the car feels with the cat fitted.
N/A and 's'.
remove it.....

[Dragon]

Originally Posted by ducatiexigeowner

Remove the cat.
Guess only a few of us notice how restricted the car feels with the cat fitted.
N/A and 's'.
remove it.....

I just headed to Autobach's and ordered a Blitz air filter for it. Evidentially the 2ZZ is not a common engine here in Japan. It looks a lot like the green filter only it's blue. It should come in next week and I'll see if that makes any difference. The Blitz air filter part # is ST-43B should anyone be interested in checking it out.

Are there any issues running the stock map with out the cat? I don't want to go threw the send the computer out for a retune and wait and then hope it works crap. I also don't want to waste the $ on doing that since I plan on getting a supercharger in the near future. Even then I don't feel comfortable getting the supercharger unless I have the ability to tweak the map for future mods and higher boost.

I've also noticed the flywheel in this thing is way too heavy. I'm actually quite disappointed in the performance as far as engine power and response goes. It's not what I expected from all the reviews I'd seen on the car. I'm used to playing with Rx-7's I've built with 400-600hp, so maybe I'm a bit spoiled. I do love the car, its looks and handling, but there is a HUGE improvement to be made in the engine department. I also think that there is still something a little off with it as well.

[shay2nak]

afaik, the stock ecu is encoded, so you can't just plug something in a play around with the parameters. Unless, you get a piggyback ecu.

BTW, decatting will also get you a CEL.

The motor is entirely stock 2zz that you find in a celica gts. all of it except for the ECU.

[Dragon]

http://www.apexi-usa.com/product_ele...=260&pageNum=1

Hrm.. has anyone played around with running something like this on the lotus to control the cam change over point and adjust fuel like the honda's do?