smokenpony

As I posted yesterday my GT has been running sluggish and has a hesitation, so I take it into Mustang Specialties last night to have them take a look at it. After test driving it they put my car on the dyno and the results weren't so great. My best run was 283 hp 294 torque, the tech claims I should be getting 305 -315 hp. The biggest problem was the air-fuel mixture. Started out at 14.2 but dropped dramatically to 12.3 at about 2000 rpms. After the drop the line wasn't constant it looked like someone drew a line with shakey hands. They triedto refine my tune to correct the situation but had no luck. I was told they would need the car for a full day to analyze the problem and find out what's was causing this to happen. They recommeded to go back to stock and maybe replace my CAI with a steeda and a Diablo predador tuner. Right now I have a JLT with an SCT tuner. The tech was great, he said if wetried that, he would install it then put my car back on the dyno and if it didn't correct the problem he would take it back off and not charge me. Not sure if I really want to go this route yet because if it did work I have to fork out $790.00 I'm thinking about just putting my car backto stock and taking it into Ford and let them figure this out.

Does anyone have any other suggestions? I dread the thought of taking my car into the dealership.

SuperSonic05

Do you just havea JLT and a canned SCT tune, if not what mods do you have?

This sounds a little fishy. I mean air is air, usually the more the better(as long and you can keep the mixture right). I thought the JLT was the one of the best intakes and most popular. Therefore, you’d think that they should be able to adjust tune for you.

I hope someone can help him out, I’ll keep watching.

smokenpony

The only other performance mod I have are flowmaster 40's. I have a 93 and 87 tune from Doug at Bamachips and a 93 perf tune from a D' Agostino Racing. I thought JLT was one of the better CAI too.

MustangGT0405

If the numbers you are quoting are rear wheel then I think your car is fine. People dont make 315rwhp with a CAI tune and axlebacks (actually mufflers make 0 hp anyway)

Now the funky A/F is strange. I would check the 02 sensors and the MAF. Something is weird.

smokenpony

I thought maybe it might be the sensors butthe system isnot throwing any codes,The techthought maybe my tune was set up so the system wouldn't display any codes so he downloaded a tune that he had on a diabloand the the system stillno codes. We were both shaking our heads on this problem. I may just have to send it over to the Ford dealership and have them check this out.

w1ck3dr1

yeah, from what i know, your car will not make 315 rwhp with just and intake/tune. 280-285 is about right. was this on a dynojet or a mustang dyno? as for the shaky lines, i'm unsure, maybe ignition, spark plugs?

PLstang

The rwhp numbers are what they should be. Do you have a copy of the Dyno sheet.

Either way take the car somewhere else. Any tech that tells you your gonna get 315 rwhp from a tune and a cai has to be questionable in my book. Maybe I'm wrong but thats my opinion.

ski

If your car is sluggish and hesitates with all of your tunes, and the same problems also happened with the tech's Predator tune, then it's possible thatthe tunes arenot the cause.
Make sure that all of the CAI's connections are air tight(plastic CAI's have been reported to warp, and thus cause air leaks), and the MAF sensor's rubber gasket is installed.
If those are ok, then see if cleaning the MAF sensor fixes things.

GidyupGo

Were you on the same page as the tech? He may have been thinking flywheel and you RWHP.

Simon1

Sometimes adjusting the position of your MAF will also cause different readings and thus different power.

Your power level is where it should be. It sounds to me like the tech is trying to make some money off you. I would ask him to fine tune the a/f to where it should be and leave it be.

There is no way your car should be making 305-315 with only a CAI and tune.