I am sure it is marginally worse than the stock cat, but substantially better than none. You can pass the smog test with a magnaflow cat, I know from experience.

 

mmmhhh.... weather is definetly a factor. Wouldn't TPS be much more accurate and therefore deliver better driveability though?

 

accurate in the sense that you can set fuel at a set rpm and trottle position? well map is accurate as well, you can set the fuel at certain load plus you can make it more accurate... you can do corrections based on barometric pressure change, you cannot do that with tps.

lets say you tuned TPS based on today's weather, nice 80 degrees. so you set your fuel based tps and rpm.... say tomorrow weather got cold, how you think your car react to the same tune?

 

I got the weather part and I agree, just seems that driveability could be vastly improved 'cause the vacuum pressure with ITB's is pretty low relative to stock.

What about a combination TPS/MAP tune

 

Got my car retuned by Shad at Driving Ambition (while I wait for Asura to buy himself a Dyno!)

Shad retuned the car, all via TPS, which Asura had done as well. The power gained was about 8HP BUT I had put in the catalytic converter after the last tune.

The big difference was 2 fold, the originally installed throttles' spring was too soft so when the car was hot it would actually idle weird - it now has a much tougher spring and it drives MUCH better and idles perfectly - also the resulting tension allows me to feather the throttles much easier than before.

The second difference is that driveability has been improved accross the range. The sound of the throttles changed at WOT and the car is more responsive, even if I stand on it at 4,000RPM on 6th gear.

I was considering getting rid of the ITBs as they have been such a PITA with all the tuning and because I can't go to Laguna, my closest track. I can't imagine giving them up now. I'll run them til that engine blows up

https://www.s2ki.com/forums/index.ph...&f=12&t=586286

 

all you need is a EMS or pre DBW ecu, throttle cable and componets, and convert your fuel system to return style. or is there something else?

I think that and ITB install would be more worthwhile than high compression pistons.

 

good for you....

all those you mentioned (i.e. driveability, cold start idle, etc. etc.) i dont have problem with my tune via manifold absulote pressure (map) and i've been tuning it myself. and yeah you can tell if the tune is good by the sound of the engine, now that you hear a nice sound... you prolly have better mixture too than your previous tune.... i was listening to your car at the last autox at ggf and it sounded too lean.

good luck if you are gonna get rid of it, too bad it's a PITA for you.



whats next? FI?

 

nothing, I'm keeping her

 

Have you guys ever run your itb's without the bellmouths?

How much of a difference have you guys noticed with/without them?

 

only at idle, no difference then but I understand the shape of the horns is a massive component of their performance...