OFT and Auto Transmission

[Jrider]

This might be a stupid question but is the OFT compatible with a AT?

Will the OFT lean out a car that might be running rich?

Thanks

[phrosty]

It's compatible with AT, though it does not tune your TCU.

If by "rich" you just mean LTFT, you can set your AFR just about however you want, and correct your sensor calibrations. Depends on what is causing your car to run rich.

[Jrider]

Thank you for the reply. Basically I am running the 2.5 inch perrin cold air and I have a 2.5 perrin catback. A buddy at work who heard it says he thinks it sounds rich. He stated that most cars run rich to break in the engine from the factory, but they should be leaned out to get the most power. I noticed a slight bog after I put on the exhaust. I was hoping a OFT tune would possibly fix this. I don't live near a dyno tuner. And obviously I am new to all of this car stuff. Any suggestions?

[DGM-BRZ]

Originally Posted by Jrider

Thank you for the reply. Basically I am running the 2.5 inch perrin cold air and I have a 2.5 perrin catback. A buddy at work who heard it says he thinks it sounds rich. He stated that most cars run rich to break in the engine from the factory, but they should be leaned out to get the most power. I noticed a slight bog after I put on the exhaust. I was hoping a OFT tune would possibly fix this. I don't live near a dyno tuner. And obviously I am new to all of this car stuff. Any suggestions?

Tbh, regardless if itll fix it or not, get the OFT, stage 1 tune it. Work on getting a header and then stage 2 tune it. It'll be noticeably faster.

Also, turn on sports mode when you drive, it makes the car way more fun to drive. Instead of 2.5k rpm gear shifts, its now like 3-3.5k shifts

[Jrider]

Originally Posted by DGM-BRZ

Tbh, regardless if itll fix it or not, get the OFT, stage 1 tune it. Work on getting a header and then stage 2 tune it. It'll be noticeably faster.

Also, turn on sports mode when you drive, it makes the car way more fun to drive. Instead of 2.5k rpm gear shifts, its now like 3-3.5k shifts

The only problem is that I live in CA, there are no CARB approved headers that I know of. And I drive the car 95% of the time in "manual" mode, using the shifter to shift up and down. I see you have a AT as well. It is nice to have the ability to auto when you want higher gas mileage.

[KoolBRZ]

Originally Posted by Jrider

The only problem is that I live in CA, there are no CARB approved headers that I know of. And I drive the car 95% of the time in "manual" mode, using the shifter to shift up and down. I see you have a AT as well. It is nice to have the ability to auto when you want higher gas mileage.

If you already have an OFT, then give me your CAL ID, and I'll send you a tune. It will start quiet, accelerate smoothly, won't overheat, get from 20 to 40 city or highway MPG, and will have more low-end torque than what you have now. It also comes in E85. Oh, and it's still free and Open Source.

[Jrider]

Originally Posted by KoolBRZ

If you already have an OFT, then give me your CAL ID, and I'll send you a tune. It will start quiet, accelerate smoothly, won't overheat, get from 20 to 40 city or highway MPG, and will have more low-end torque than what you have now. It also comes in E85. Oh, and it's still free and Open Source.

I do not have one yet. I am trying to research my options before I buy. However this looks like the route I will be going. Do you have an AT? What sort of other mods do you have on your car? Is this something that you calibrated yourself?

Thanks for the offer as well

[phrosty]

Ultimately, you will need to do some data logging to be sure. There is no rich "sound" -- that's a new one! OFT can help you diagnose it, but so can a $10 OBDII reader with Torque.

Perrin's intake was designed to run perfectly fine without a tune, and catbacks have virtually no effect when NA. Your parts won't cause issues if they're correctly installed. Make sure your intake install didn't create a vacuum leak, and make sure oil hasn't slung onto the MAF.

[KoolBRZ]

Originally Posted by Jrider

I do not have one yet. I am trying to research my options before I buy. However this looks like the route I will be going. Do you have an AT? What sort of other mods do you have on your car? Is this something that you calibrated yourself?

Thanks for the offer as well

The top two things I recommend for AT owners;

1. OFT and Ebay extension cable with on/off switch.

2. 4.88 Final Drive

The OFT costs $499, or less if you buy it used.

The 4.88 FD costs $238.70 for the gears alone, (Weir Performance), and the rebuild parts can run from $50 to $500, depending on if the bearings need replaced or not. Labor is usually from $200 - $500 depending on the shop, and whether or not you remove/install the pumpkin yourself.

The FD is the absolute cheapest power mod you can do to your car without affecting emissions. The speedometer is unaffected, speed is measured at the wheels. The transmission acts like it was always meant to be geared this way. It takes the load off the engine and trans, and puts it where it belongs, on the axles and tires. A 4.88 FD really makes this car move like it's supposed to.

I bought a second rear carrier to put my 4.88 FD in, so I can switch back to my 4.10 for road trips. I also have slightly taller tires, (225-45-17 Conti extreme contacts) for better grip and a better ride, and a 4.88 FD compensates for this.

[MGPAX]

Originally Posted by KoolBRZ

The top two things I recommend for AT owners;

1. OFT and Ebay extension cable with on/off switch.

2. 4.88 Final Drive

The OFT costs $499, or less if you buy it used.

The 4.88 FD costs $238.70 for the gears alone, (Weir Performance), and the rebuild parts can run from $50 to $500, depending on if the bearings need replaced or not. Labor is usually from $200 - $500 depending on the shop, and whether or not you remove/install the pumpkin yourself.

The FD is the absolute cheapest power mod you can do to your car without affecting emissions. The speedometer is unaffected, speed is measured at the wheels. The transmission acts like it was always meant to be geared this way. It takes the load off the engine and trans, and puts it where it belongs, on the axles and tires. A 4.88 FD really makes this car move like it's supposed to.

I bought a second rear carrier to put my 4.88 FD in, so I can switch back to my 4.10 for road trips. I also have slightly taller tires, (225-45-17 Conti extreme contacts) for better grip and a better ride, and a 4.88 FD compensates for this.

I did the Weir 4.88 also. I love it. But I have a good bit of whine when it warms up. Especially on decel. Is yours completely quiet? And do you know of a way I can quiet mine down a bit?

[KoolBRZ]

Originally Posted by MGPAX

I did the Weir 4.88 also. I love it. But I have a good bit of whine when it warms up. Especially on decel. Is yours completely quiet? And do you know of a way I can quiet mine down a bit?

So long as there aren't any metal shavings in the differential fluid, a little whining is OK. I recommend changing your fluid anyway, since there will always be some metal shaving during the break in period.

I don't have mine in yet. I had the gears in once before, but changed to a 4.30 to get better mileage. Now I don't need the mileage anymore, so I bought a second rear carrier, which is sitting in my trailer till Tuesday, when the shop opens back up again. I'll be swapping out pumpkins in my driveway, once I get it back. When I had mine in before, it whined, but I could spin rubber in three gears before the TC kicked in.

[Wayno]

Originally Posted by MGPAX

I did the Weir 4.88 also. I love it. But I have a good bit of whine when it warms up. Especially on decel. Is yours completely quiet? And do you know of a way I can quiet mine down a bit?

My builder was utterly unimpressed with the quality of the weir parts compared to the stuff out of Japan.
There are others who've had nothing but problems with the 4.88 too.

[KoolBRZ]

Originally Posted by Wayno

My builder was utterly unimpressed with the quality of the weir parts compared to the stuff out of Japan.
There are others who've had nothing but problems with the 4.88 too.

The lash HAS to be set correctly with Prussian Blue compound. Any other gear setting compound can give erroneous results. It is a complex procedure for an experienced technician. Even with an expert install at the correct gear lash with the correct setting compound a Weir gear set can still whine. When I get mine back I'm sure it will whine for the first few thousand miles as well.

[phrosty]

I'll be installing a built 4.88 from Spencer soon, curious to see how that'll go.