Tuning Conundrum

[re-rx7]

Originally Posted by TrueStreetTim Give me a call at the shop if you'd like. Ask any questions and address any concerns you may have with tuning whether it be "mail order" or otherwise. My typical pitch: If you like what I have to say, great! If not...that's cool too!

Tim would you say a Tune is needed with a O/R X or H? From what I've researched the COT protection only kicks in on decel? The worst I can see happening is you run a tad bit richer and a check engine light. SOme tunes like AED and such have specified they dont change anything just remove the Check Engine light? Input?

[DirtyD]

Originally Posted by re-rx7 Tim would you say a Tune is needed with a O/R X or H? From what I've researched the COT protection only kicks in on decel? The worst I can see happening is you run a tad bit richer and a check engine light. SOme tunes like AED and such have specified they dont change anything just remove the Check Engine light? Input?

You, you will need a tune when you delete the cats. If not, the car will run open loop and just dump fuel trying to cool the cats that aren't there anymore. You will run rich and get horrible gas mileage and a putrid smell.

[re-rx7]

Originally Posted by DirtyD You, you will need a tune when you delete the cats. If not, the car will run open loop and just dump fuel trying to cool the cats that aren't there anymore. You will run rich and get horrible gas mileage and a putrid smell.

Your talking about COT protection. It only happens on Decel. Rear 02's do not control anything. they have a voltage reading of .1 to 1. The front Wideband 02's read .1 to 5 volts they would tell the ecu to run in open loop.

[Courtesy Flush]

Originally Posted by re-rx7 Your talking about COT protection. It only happens on Decel. Rear 02's do not control anything. they have a voltage reading of .1 to 1. The front Wideband 02's read .1 to 5 volts they would tell the ecu to run in open loop.

Im not speaking for the rest, but a good tune has more done than just turning off COTP & nannie lights on these cars with no cats. Thats just one part of it.

[re-rx7]

Originally Posted by Courtesy Flush Im not speaking for the rest, but a good tune has more done than just turning off COTP & nannie lights on these cars with no cats. Thats just one part of it.

Thats why im asking Tim to chime in. I already have a tune. just needing to know if it needs another one. All your doing with the exhaust is increasing flow after the combustion process so the power gain comes form the flow not the actual tune.

[Courtesy Flush]

Originally Posted by re-rx7 Thats why im asking Tim to chime in. I already have a tune. just needing to know if it needs another one. All your doing with the exhaust is increasing flow after the combustion process so the power gain comes form the flow not the actual tune.

I understand. If you currently have cats with your tune and will be removing the cats, yes your tune needs to be updated.

[TrueStreetTim]

Originally Posted by re-rx7 Tim would you say a Tune is needed with a O/R X or H? From what I've researched the COT protection only kicks in on decel? The worst I can see happening is you run a tad bit richer and a check engine light. SOme tunes like AED and such have specified they dont change anything just remove the Check Engine light? Input?

When you remove the cat's with no tune changes, it indeed becomes rich. But it actually over-richens itself so much so that it's a power losing state of richness. It exhibits that state under cruising, WOT the whole bit. Not just decel.

So, yes. If you delete cat's you'll need to make more changes to the computer than the car is able to handle on it's own or simply turning off a code.

OP; if you've already paid for a tune and need changes for O2's to be made etc. call SCT and have them make the changes and go from there until your ready for custom. Axle-backs need no changes as they are post O2 and you won't experience CEL's.

[re-rx7]

Originally Posted by TrueStreetTim When you remove the cat's with no tune changes, it indeed becomes rich. But it actually over-richens itself so much so that it's a power losing state of richness. It exhibits that state under cruising, WOT the whole bit. Not just decel. So, yes. If you delete cat's you'll need to make more changes to the computer than the car is able to handle on it's own or simply turning off a code.

Thanks for the input Tim.

[GTOphil]

Originally Posted by TrueStreetTim OP; if you've already paid for a tune and need changes for O2's to be made etc. call SCT and have them make the changes and go from there until your ready for custom. Axle-backs need no changes as they are post O2 and you won't experiencce CEL's.

Thank you for the response. I had the axle back when I got the tune/tuner from American Muscle/Bama...so the tunes are the same and I don't need changes.

I guess I just kinda got spooked by some of the guys on here talking about #8 this and canned tunes that.

Having said that I DO realize a custom tune is best (had my GTO tuned for every little thing I changed) but since I'm so close to stock it seems as if everybody suggest Bama is fine for now.

The only reason I want to datalog is to ensure the tune is plenty safe- though they did say they made some changes to their tunes since last summer so I won't be opposed to extra power.

The two MAIN reasons for a custom tune would be to ensure safety and get more power if possible.

[Soulowd]

GTO just posted better Dyno results so you can read them better man