tuning?

[Flamed Merc]

Ive got a 03MM with DR vortech Noic kit installed in the next month I will be adding a intercooler from DR and 4.10 gears.My question is does the car need to go to the dyno right away for a retune or will it be safe for awhile? I realize it needs programed for the gears but does it need dynoed?

[fastblackmerc]

I wouldn't get on it before getting the tune. Don't drive it like you stole it.

[Flamed Merc]

Why not drive it hard? Can't the trans shift points be set without a dyno? As far as the intercooler what wood be the difference of driving it on a cool day the way it is (noic)? My understanding is with the cooler added I can bump timing and boost up for more hp so without the retune what changes? Should just lower iats .right?

[teamrope]

The problem will be with the A/F. You're going to be adding a lot more air without changing the amount of fuel added. WOT it will lean out on you and blow the motor.

[Flamed Merc]

How will it get more air ? Don't understand. All you are adding is longer tubing and a cooler no increase in boost and no less restriction. Like your flames all MM need more personality. Mine cover more of the car but not as bold

[SC Cheesehead]

How will it get more air ? Don't understand. All you are adding is longer tubing and a cooler no increase in boost and no less restriction. Like your flames all MM need more personality. Mine cover more of the car but not as bold

You're right.

Don't worry about the tune, just drive like you stole it.

tick tock, tick tock...http://www.freesmileys.org/smileys/smiley-basic/atomic.gif (http://www.freesmileys.org/smileys.php)

[Flamed Merc]

Look I'm trying to understand, I drove the car to my shop today mid 30 temps out side, car runs perfect and a/f ratio is fine so how is intercooler going to lean it out it has a dyno tune with supercharger just not with intercooler

[SC Cheesehead]

Cooler air is denser air.

Denser air will impact the A/F ratio; more air, less fuel per cubic unit of air flowing into the engine.

More air, less fuel = lean condition at WOT.

Lean condition at WOT = http://www.freesmileys.org/smileys/smiley-basic/atomic.gif (http://www.freesmileys.org/smileys.php)

BOOM = Bad.

[MOTOWN]

think about what an intercooler does?, cooler air makes more power thereby needing more fuel!
cooler air=more hp!, more hp needs more fuel

[Flamed Merc]

So on a day like today the iat only got up to like 120 all the way to the shop with a cooler it cant go below outside temp so why doesnt it run lean in cold weather, agreed it does run a bit leaner but the ecm seems to controll this with in reason. I will get another tune as soon as I find someone who can get it right and not a days drive away

[MOTOWN]

well cold air is more dense as stated, and your not likely to go wot in cold/slippery weather unless you have a death wish

[Pat]

Don't confuse the A/F ratio adjustments done by the computer at part throttle. The A/F will be maintained at 14.7 to 1.

At Wide Open Throttle the computer reverts to another method of calculation, this is the mode that tumers work with. Trying for an 11:1 ratio across the RPM band.

Hardware changes need to be factored in at WOT more than part throttle.

[LANDY]

How do you know your fuel ratio is good. Do you have a Wideband?

[teamrope]

How will it get more air ? Don't understand. All you are adding is longer tubing and a cooler no increase in boost and no less restriction. Like your flames all MM need more personality. Mine cover more of the car but not as bold

Thanks for the props. You will have to post pics of your flames. :)

[MM_BKK]

If your set up was tuned properly initially factoring for no intercooler. Most likely and hopefully the tune will be conservative in the timing department. Adding the intercooler without a retune would just increase the safety margin since the IAT will be lower thus less chance for detonation (#1 stock cast piston and rods killer) and there will be a slight drop in boost due to pressure drop caused by the intercooler. The only downside to not getting a retune is you will be leaving some HP on the table. To fully benefit from the intercooler, you should also change out your pulley to increase boost to overcome slight loss and then pick up some extra since the IAT will be lower and the motor can take more boost.

As far as not getting a retune and possibly seeing a lean condition due to cooler charge providing more air is probably not going to happen. All the air molecules have to go through the MAF and if there is a slight increase due to cooler denser charge, the PCM will compensate for it and add more fuel accordingly.

[Flamed Merc]

This is what I thought And I do plan to retune but would rather wait to tune in warmer weather .I do have a broadband and know the A/F ratio is running alittle on the fat side. When it was dyno tuned I had the guy tune it to where he felt I couldn't hurt the motor then backed it down alittle more. My idea is to add intercooler and bump her up now.Ive had this car 4 years and put 7000 mi on it.So its time to go play. Now for the other question Can I recalibrate the shift points for 4.10s with my sct tunner. Since original tune if the car breaks loose even alittle at wot it will hit rev limter when it shifts so I assume this is going to be worse unless corrected.Thanks for all comments.
Car now has 21000 mi