Question About SAI S/C Tune

[mffarrell]

My car is going into the mod shop next month for an S/C installation, gauge pod, lower driving lights, and brake duct kit.

 

Is the SAI tune sufficient for the Paxton S/C, or will I need to have a custom tune? I would like to optimize hp, but not at the expense of potentially damaging the engine.

 

What do you think?

 

Thanks!

[clark17357]

My car is going into the mod shop next month for an S/C installation, gauge pod, lower driving lights, and brake duct kit.

 

Is the SAI tune sufficient for the Paxton S/C, or will I need to have a custom tune? I would like to optimize hp, but not at the expense of potentially damaging the engine.

 

What do you think?

 

Thanks!

 

My car is on the same track as yours and for the same modification. I join in the request for the collective wisdom of the Forum on this topic. Thanks. Jim

[CudaFly]

My car is going into the mod shop next month for an S/C installation, gauge pod, lower driving lights, and brake duct kit.

 

Is the SAI tune sufficient for the Paxton S/C, or will I need to have a custom tune? I would like to optimize hp, but not at the expense of potentially damaging the engine.

 

What do you think?

 

Thanks!

 

 

I would guess 90%+ of owners with an SC installed (Paxton/Whipple/other) would recommend you find a good tuner with a lot of experience on supercharged 4.6L 3V Mustangs and get a baseline dyno run and a custom tune/dyno.

 

The stock OEM tunes from the SC manufactures will all work but there is a huge difference in the responsiveness and performance with a custom tune.

 

At a minimum, if you don’t get a custom tune you should get a dyno to verify the A/F ratio, fuel pressure, boost levels, and other parameters of the OEM SC tune. Putting a SC in is a fairly radical modification and I can’t see just bolting it on and assuming everything is working OK.

 

I’m a little surprised SAI doesn’t have a dyno or take their SC modified cars to a local dyno in Vegas after the installs just to make sure everything is OK. It’s easy to have subtle issues with fuel pressure, electrical, air leaks, etc that would not be obvious until you have it on the dyno with the right analog sensors attached.

 

After spending $6K+ for a SC install the extra $100 for a dyno to verify the performance is money well spent.

[SGT2666]

Whipple and Ford spent a lot of time and money on the engineering and tune both for power and safety. I'm really torn on whether that should be messed with.

[CudaFly]

Whipple and Ford spent a lot of time and money on the engineering and tune both for power and safety. I'm really torn on whether that should be messed with.

 

 

Yes you have a good point. And of course there are potential warranty issues if you change the SC OEM tune. So maybe my 90+% guess was a little high. I was just assuming most people that get a SC installed are looking to maximize performance and aren't too worried about stretching the mechanical limits and/or voiding the warranty.

 

Even with a stock OEM SC install/tune (no custom tuning or mods) you are still pushing the mechanical design limits of the 4.6L 3V engine. With any SC insatalled you will have more wear and tear and lower the life expectancy of many of the engine and drive train components. That’s just a side effect of more HP/Torque.

 

For me there is no question that the custom tune (performed by a qualified tuner) is the way to go. But I'm sure there are a lot of people satisfied with the stock OEM SC tunes.

[ShelbyPilot]

I highly recommend getting at least a test dyno pull at a competant performance shop. I am speaking from experience and there should be a thread somewhere on the forum if you care to search. In a nut shell. My Shelby GT/SC came from the Mod shop with a detonation problem at tip in around 2700 RPM. It was real predominant when trying to accelerate from a freeway cruise or under hard acceleration with quick shifts.

 

I took it to a tuner and found two things. First, there was one cell that the ignition was way off. When that was corrected the detonation went away. However, the second thing was huge. The diagnostic tune revealed that the air to fuel mixture was so rich that the result didn't even show up on the graph. RWHP was only 341. Well below he 462 engine HP advertised by Paxton.

 

After a tune from a Paxton certified installer the air fuel mixture was set right and the car made 441 RWHP on a conservative tune.

 

In short at the very least pay attention to your car and take it for a base pull. As Cuda said $100 (to $150) for piece of mind. Plus you know exactly what you have. Then if you want to squeez performance you can go for more. I would reccomend using a Paxton or Whippple authorized installer that routinely dynos there installs. That should cover any warranty issues with the supercharger.

[mywickedshelby]

wow chris, between that and the fuel pump issue, I guess SAI workmanship wasnt so good for you.

How did that get past quality control?

Sometimes, its not so good to be first.

[supercharged07shelby]

i agree 100 % the custom tune is the only way to fly. i installed a s/c on my shelby and downloaded the tune that come with it and the car is diffently rich. a good hard day of driving and the tips are black a custom tune would eliminate that problem. i am having mine retuned on a dyno to solve this problem and the drivibilty issues it has. the cost of the tune is well worth the peace of mind knowing that everything is 100 %. a local dyno shop that is familiar with the s/c 4.6 motors would be able to tune the car. ask question about who s tuning cars in your area and find somebody thats has a good reference.