HPTune

[Sniper]

Will the HPTune be able to do the same thing as a Prefix PCM?

Revised fuel, spark and cam position tables that maximize power increases associated with engine modifications and/or exhaust systems
-Aggressive off-throttle exhaust note
-Requires min 93 octane fuel.
-Rev limit increased to 6600 rpm with decreased hysteresis.
-Allows racing approved final drive ratios from 3.07:1 to 4.10:1.
-First to fourth gear skip shift eliminated for racing use.
-Catalyst monitor disabled to allow the use of high flow / or no catalyst and headers
-Air flow rationality diagnostic disabled which permits greater range of flow modifications
-Misfire detection disabled to permit reduce mass rotating assemblies and further modifications

[Mikey]

Will the HPTune be able to do the same thing as a Prefix PCM?

Revised fuel, spark and cam position tables that maximize power increases associated with engine modifications and/or exhaust systems
-Aggressive off-throttle exhaust note
-Requires min 93 octane fuel.
-Rev limit increased to 6600 rpm with decreased hysteresis.
-Allows racing approved final drive ratios from 3.07:1 to 4.10:1.
-First to fourth gear skip shift eliminated for racing use.
-Catalyst monitor disabled to allow the use of high flow / or no catalyst and headers
-Air flow rationality diagnostic disabled which permits greater range of flow modifications
-Misfire detection disabled to permit reduce mass rotating assemblies and further modifications

Yes and you'll make more power than an arrow pcm

[Sniper]

Thanks! That’s nice to know!
I’m so hoping to get to at least 650rwhp with the heads cam setup.

[Steve M]

If you are going through a tuner, ask him/her that question.

If you are wanting to tune it yourself, I'll issue this warning: HPTuners has changed, and not for the better. I can only assume the EPA got to them, as they have greatly restricted the end-user's ability to modify anything related to emissions equipment.

That may or may not be a big deal to some, but to me, it would be a deal breaker.

What I don't know is if they've implemented the same restrictions on professional aftermarket tuners.

[Sniper]

Steve what specifically would HPTuners not be able to do now emissions wise that would be a deal breaker?

[Steve M]

Personal example: I run high flow cats.

Those cats throw an inefficiency code.

With HPTuners the way it is now, that code would not be able to be turned off.

I hate idiot lights on the dash. I know the cats are inefficient - that's why I bought them. They clean the exhaust up well enough that I don't ever smell it, but the computer (and the Feds I guess) thinks otherwise.

It's more of an annoyance than anything for me, but again, I don't know what else you can and can't do these days, and HPTuners isn't exactly forthcoming about it. For instance, adding a fixed cam to replace the OEM one. Seems like that might trigger a few check engine lights too.

Again, things for a professional tuner might be different, but you're still giving up the ability to do anything yourself with the software, which was 99% of the draw to it.

My $0.00.

[Sniper]

Gotcha! I’ll ask the shop what they will and will not be able to do.

[Jack B]

I am not sure HPT could ever modify the drive ratio error created by a gear change. A 3.73 might not create any issue, whereas, the 4 11 probably would. Prefix can fix that issue with a custom pcm flash.

[Sniper]

So, basically if anyone wants to modify their Viper in any way, the only option now is Prefix PCM and their heads/cam package?

[Steve M]

I am not sure HPT could ever modify the drive ratio error created by a gear change. A 3.73 might not create any issue, whereas, the 4 11 probably would. Prefix can fix that issue with a custom pcm flash.

Can't speak for the Gen 5 crowd, but this functionality exists for the Gen 4.

You have to dig for it, but the table is there.

I've had to modify mine for each gear swap I've done - both 3.55s and 3.73s.

[Steve M]

So, basically if anyone wants to modify their Viper in any way, the only option now is Prefix PCM and their heads/cam package?

If you want to run the stock PCM, it is probably your best bet at this point, especially since they'd have the source code.

But you could always run a different engine management system; you'd just have to open your wallet up a bit more. And it would certainly give you way more flexibility depending on the skill of the installer/tuner. Calvo and Nth Moto would be the ones to talk to about that.

[FrgMstr]

Calvo and Nth Moto would be the ones to talk to about that.

Not speaking for Calvo, but I do believe Antonio told me that my car was the Gen IV heads and cam car he was going to do with HPTuners. My car was delivered on June 18, 2021. I would certainly call to make sure however.

[Mikey]

Personal example: I run high flow cats.

Those cats throw an inefficiency code.

With HPTuners the way it is now, that code would not be able to be turned off.

I hate idiot lights on the dash. I know the cats are inefficient - that's why I bought them. They clean the exhaust up well enough that I don't ever smell it, but the computer (and the Feds I guess) thinks otherwise.

It's more of an annoyance than anything for me, but again, I don't know what else you can and can't do these days, and HPTuners isn't exactly forthcoming about it. For instance, adding a fixed cam to replace the OEM one. Seems like that might trigger a few check engine lights too.

Again, things for a professional tuner might be different, but you're still giving up the ability to do anything yourself with the software, which was 99% of the draw to it.

My $0.00.

My Tuner said that wouldn't be a problem, but I guess I'll find out once I get my motor back

@Sniper 650whp is a given, you could squeeze out a fee more horses with a proper tune

[Sniper]

Torrie will be the tuner

[Mikey]

Torrie will be the tuner

Torrie will NOT touch anything emissions related.

[Sniper]

But the shop can alter the emissions stuff with hptuners, correct?

Are you using something different than hptuners for your build?

[Mikey]

But the shop can alter the emissions stuff with hptuners, correct?

Are you using something different than hptuners for your build?

The shop can. I assume you're renting the dyno and having Torrie tune? I'd clear that up with the shop first before you spend the money.

[Sniper]

Ok, just got off the phone with the shop and I either misunderstood or got my stories messed up with something I red on the forum but the shop already has the software and they are tuning the car themselves, nothing to do with Torrie.

What software for tune are you using?

[Mikey]

Ok, just got off the phone with the shop and I either misunderstood or got my stories messed up with something I red on the forum but the shop already has the software and they are tuning the car themselves, nothing to do with Torrie.

What software for tune are you using?

I got mine sent in remotely from Torrie. It's 20 credits ($1,000) to unlock the ECU, it may be worth purchasing your own dongle in case you need it retuned

[Lawineer]

Are you guys sure it can't shut off the inefficient cat code? Seems odd that it can turn off emissions certain codes but not others.

Also: Can someone explain this?

Misfire detection disabled to permit reduce mass rotating assemblies and further modifications. To my understanding, the misfire is detected when the crank position sensor expects a big boom to accelerate the crank on a power stroke TDC, but there is not an acceleration as expected. So if anything reduced mass would mask a misfire, not create one, right?

[Sniper]

To me it sounds like tuners can do everything like they used to with hptuners but Torrie is choosing not to.
My shop didn’t see any issues with doing whatever is needed with hptuners. They’ve already got some Gen Vs they’ve modified with more than I’m doing.

[Mikey]

To me it sounds like tuners can do everything like they used to with hptuners but Torrie is choosing not to.
My shop didn’t see any issues with doing whatever is needed with hptuners. They’ve already got some Gen Vs they’ve modified with more than I’m doing.

Yeah, it's the first time I'm hearing shops not being able to turn of 02 sensors etc. I just know certain tuners opt not to due to increasing emission crackdowns

[Jack B]

If your state has dynamic e-check, you cannot hide the tune

[VENOM-TA]

Mine is tuned with HP tuners by Prospeed in Houston.. I have ARH Headers, no cats and Corsa sport exhaust.. no issues, no CEL lights and passes emissions when plugged in to the OBDII port..

[Lawineer]

If your state has dynamic e-check, you cannot hide the tune
This makes a lot of sense. EPA has been cracking down.

[ViperGeorge]

If your state has dynamic e-check, you cannot hide the tune

What is "dynamic e-check"?

[Sniper]

Yea, I’ve never heard of this either. I don’t think MO has this.

[No hemi]

Calvo does NOT do hp tuners anymore, My car is a Calvo H/C and is tuned with HP tuners, Torrie @ unleashed tuning did the tuning and car works great, still have a check engine light on but It's epa related, non the less he would be the person to contact to get it tuned right, also I think Cordes performance and you can ask Nth too( Aaron Miller) about this.

[FrgMstr]

Calvo does NOT do hp tuners anymore, My car is a Calvo H/C and is tuned with HP tuners, Torrie @ unleashed tuning did the tuning and car works great, still have a check engine light on but It's epa related, non the less he would be the person to contact to get it tuned right, also I think Cordes performance and you can ask Nth too( Aaron Miller) about this.

Karger (https://www.facebook.com/CalByKarger/) did my Calvo build tuning at a dyno shop in Denton, TX. No CELs. TX inspection worthy.

[Mikey]

Karger (https://www.facebook.com/CalByKarger/) did my Calvo build tuning at a dyno shop in Denton, TX. No CELs. TX inspection worthy.

Says he's in Garland now, which would be more convenient for me, actually

Can your setup run e85? I noticed calvo heads and cam tend to make more than prefix

[Reaper]

Is this why the Calvo heads/cam kit has gone up like 10K? Now on the description for the kit, it says Motec. They used to use HP Tuners on your stock PCM. I really wanted their kit but not for 30K

[FrgMstr]

Says he's in Garland now, which would be more convenient for me, actually

Can your setup run e85? I noticed calvo heads and cam tend to make more than prefix

He may be in Garland now. The shop we could get dyno time on that particular day was not his to my knowledge.

I did not have it tuned to run e85. You might be able to call Karger and ask about that.

Again, my car was setup with 2.5 cats/catbacks, and Belanger headers. Antonio explained I could get another 20rwhp by moving to American Racing headers on it, and of course we had "small" exhaust on it. And it was right at 100F (~140F intake temps) in the shop, so all in all, not really great tuning conditions. Dumping the straight pipes on, it was a noticeable boost in RWHP without ever touching the tune.

The heads did have Calvo's new design at the time, and I think I was the first or second car out of his shop with that.

I did a few drives with Karger to get the car dialed in after we got it off the dyno. Tuning with HPTuners, at least for Viper, was not his favorite thing to do.

If I was going to do it again, I would have just dropped the $10K for the Motec and been done with it. If I ever get back to where I want to seriously race the car again, Motec will surely go in.

Post is here if you want the entire story: https://driveviper.com/forums/threads/28604-2008-Gen-IV-Calvo-Motorsports-Build

- - - Updated - - -


Is this why the Calvo heads/cam kit has gone up like 10K? Now on the description for the kit, it says Motec. They used to use HP Tuners on your stock PCM. I really wanted their kit but not for 30K

Bingo. Motec only.

[Old School]

One thing I don't like about HPtuners, at least with a Gen3 JTEC+, is that you have to get the tune "blessed" by HPtuners before it will proceed. You must have internet access so it can communicate with the HPtuners servers. At this point it's possible for it to change what is allowed to be tuned in order to follow current EPA directives. Maybe your current tune has no CEL, but after changing something insignificant, that CEL comes on?

[Steve M]

I did a few drives with Karger to get the car dialed in after we got it off the dyno. Tuning with HPTuners, at least for Viper, was not his favorite thing to do.

If I was going to do it again, I would have just dropped the $10K for the Motec and been done with it. If I ever get back to where I want to seriously race the car again, Motec will surely go in.

I'd listen very carefully to the voice of experience here.

HPTuners is a fine tool, but in the case of the Gen 4/5 Viper, it is limited by the PCM it interacts with. It never was ideal, but in general, you could get it to do what you wanted within reason. It quickly meets its limitations at the heads/cam point - at or beyond that you start revealing its warts. Sure, there are band-aid solutions to get it to work, but there are usually compromises along the way, some of which could result in driveability and/or durability issues. There just aren't many things you can edit on a Viper PCM compared to other makes/models out there, and it shows. I can tell you from personal experience that I've seen some pretty fucked up "professional" tunes out there, and the average consumer would be none-the-wiser.

If you want to do things like run E85, I'd highly recommend stepping up to a Motec or something similar that can actually handle that by design. At that point, though, the skill of the tuner really comes into play. I'm not sure any aftermarket solution is going to have the polish of an OEM one...kinda hard to compete with the budgets and resources of one of the big automotive manufacturers. Sure, it might run just fine around town, but will it continue to do so at the top of Pike's Peak? The bottom of Death Valley in the summer time? That may not be important to you until you run into an unexpected situation where it doesn't.

[Steve M]

One thing I don't like about HPtuners, at least with a Gen3 JTEC+, is that you have to get the tune "blessed" by HPtuners before it will proceed. You must have internet access so it can communicate with the HPtuners servers. At this point it's possible for it to change what is allowed to be tuned in order to follow current EPA directives. Maybe your current tune has no CEL, but after changing something insignificant, that CEL comes on?

As I tried to express previously, things have changed. At some point in the not too distant future, I can see an aftermarket engine management solution being the only viable option for tuning.

[Sniper]

All I am getting is a head/cam package and I would not get that if I had to pay $22000-$30000 for it.

[Mikey]

I'll need to call around tomorrow as my Tuner hasn't been answering my texts.

What benefit does an arrow pcm have with heads and cam considering that's what vioer exchange opts for

[Sniper]

My tuner said there will be no problem tuning my car, no restrictions from hptuners.

[Steve M]

I'll need to call around tomorrow as my Tuner hasn't been answering my texts.

What benefit does an arrow pcm have with heads and cam considering that's what vioer exchange opts for

You would have the benefit of a product developed by the people that can access every last part of the OEM computer, and based on the knowledge of people that truly understand how it all works and what the engine can and can't take. It was developed as a full package, so you know it'll work. I've been around long enough to remember the tuners trying to do the same thing with HPTuners, and it was a bit rough. They've worked around it, but not without some band-aids like tossing in larger injectors and not scaling the injector flow rate tables accordingly to get around the PCM's torque calculation limitations. I've seen others zero out the knock sensors completely because they couldn't figure out how to keep the PCM from pulling timing. And those are just things I'm aware of...

Will you leave some performance on the table? Maybe, but there's always a trade of durability vs. squeezing every last ounce out of an engine. I can tell you that there's very little you can do to affect part throttle driveability with HPTuners, so if you go with a donkey dick cam to get a nice lope at idle, you might end up with some nice surging and bucking to go along with it that they'll have a hard time tuning out.

How willing are you to risk an engine by using someone that may or may not know what they are doing? Are they willing to replace your motor if they blow it up because they were a little too aggressive? There's more to tuning a car than just getting the AFR in line and adding some timing in the right places to get the best WOT numbers on a dyno.

[Mikey]

I've heard of Johnson lifters failing, I'm curious as to why Calvo still uses them

[Sniper]

Sneakysnakes lifters failed which caused him to purchase a new motor. I believe he used the prefix package

[No hemi]

Is this why the Calvo heads/cam kit has gone up like 10K? Now on the description for the kit, it says Motec. They used to use HP Tuners on your stock PCM. I really wanted their kit but not for 30K

Yup, Now it's Motec, which is way better than just HP tuners, but IMO overkill for a H/C setup.

[Voice of Reason]

Just to confirm tuners who use HPTuners are either unable or unwilling to turn off downstream O2s when someone is running headers and high flow cats? I’ve been running a Prefix PCM for 7 years with my headers and HF cats and always considered taking my stock PCM and having Torrie tune it. I know I’m leaving some power on the table vs a custom tune, but at this point if that means I’d have to look at a check engine light I’ll just stick with a little less power and keep my sanity.

[13COBRA]

Just to confirm tuners who use HPTuners are either unable or unwilling to turn off downstream O2s when someone is running headers and high flow cats? I’ve been running a Prefix PCM for 7 years with my headers and HF cats and always considered taking my stock PCM and having Torrie tune it. I know I’m leaving some power on the table vs a custom tune, but at this point if that means I’d have to look at a check engine light I’ll just stick with a little less power and keep my sanity.

Unwilling.

[Mikey]

Just to confirm tuners who use HPTuners are either unable or unwilling to turn off downstream O2s when someone is running headers and high flow cats? I’ve been running a Prefix PCM for 7 years with my headers and HF cats and always considered taking my stock PCM and having Torrie tune it. I know I’m leaving some power on the table vs a custom tune, but at this point if that means I’d have to look at a check engine light I’ll just stick with a little less power and keep my sanity.

The shop nearby said they can turn it off, it's "for offroad use only". I think it's mostly remote tuners that don't want to mess with it

[Old School]

Many tuners using HPtuners have switched over to using the RTD+ instead of the MPVI2 or MPVI3. The RTD+ (remote tuning device) only allows your tuner to edit the tune, not you. If you want to make any changes, you need to go back to them.

[Mikey]

Many tuners using HPtuners have switched over to using the RTD+ instead of the MPVI2 or MPVI3. The RTD+ (remote tuning device) only allows your tuner to edit the tune, not you. If you want to make any changes, you need to go back to them.

Just realized I have an RTD+ but will be going to a different shop. Would they still be able to use this to dyno tune?

[StrokerAce]

I've only had tuners with HP Tuners on any of my vehicles. I had the rear 02's tuned out with both in person and remote tuning. Removing knock to me is dangerous.

I wonder why the stock PCM is so limited.

[Mikey]

I've only had tuners with HP Tuners on any of my vehicles. I had the rear 02's tuned out with both in person and remote tuning. Removing knock to me is dangerous.

I wonder why the stock PCM is so limited.

Did you buy the dongle? I didn't know there was a difference between RTD+ and mvi2 when I bought it

[Old School]

I didn't know there was a difference between RTD+ and mvi2 when I bought it

Yea, the RTD+ doesn't allow you to use the editor.

[Mikey]

Now that I think of it. My builder will be tuning the engine before sending it back to me. Will I even require dyno tuning?

[Steve M]

Now that I think of it. My builder will be tuning the engine before sending it back to me. Will I even require dyno tuning?

At the very least, you'll want to verify your WOT air/fuel ratio as installed in the car, preferably done under a representative load. Or simply put - it really needs to be done on the street. If that's not feasible, a dyno will do.

[StrokerAce]

Did you buy the dongle? I didn't know there was a difference between RTD+ and mvi2 when I bought it

I haven't turned my Viper.....yet. lol

[Mikey]

At the very least, you'll want to verify your WOT air/fuel ratio as installed in the car, preferably done under a representative load. Or simply put - it really needs to be done on the street. If that's not feasible, a dyno will do.

How does that work considering he doesn't have my ecu and I currently have a tune for bolt ons?

- - - Updated - - -


I haven't turned my Viper.....yet. lol

It made a hell of a difference, 610-620 with just bolt ons

[TBSH]

If you are going through a tuner, ask him/her that question.

If you are wanting to tune it yourself, I'll issue this warning: HPTuners has changed, and not for the better. I can only assume the EPA got to them, as they have greatly restricted the end-user's ability to modify anything related to emissions equipment.

That may or may not be a big deal to some, but to me, it would be a deal breaker.

What I don't know is if they've implemented the same restrictions on professional aftermarket tuners.

you just don't update it.

I have 4 MPVI1 pros and 1 MPVI2 i use weekly lol. I don't tune vipers for a living just mine but i do GM late model LS and LT 5 days a week for years.
I have different cables for different uses. Hptuners keeps releasing new cables so you can't use it with old software but RE RE people always want to update every time something new comes out LOL.

[Steve M]

How does that work considering he doesn't have my ecu and I currently have a tune for bolt ons?

How is he tuning your engine if he doesn't have the controller?

[Mikey]

How is he tuning your engine if he doesn't have the controller?

No idea, I just know after he finishes the build it goes in the dynk to get broken in and tuned

[Steve M]

No idea, I just know after he finishes the build it goes in the dynk to get broken in and tuned

If he's putting it on an engine dyno, it will probably have its own controller associated with that setup. That will put it through its paces there, but won't help once it is in your car running on your controller, which will need to be tuned for the new engine.

[Mikey]

If he's putting it on an engine dyno, it will probably have its own controller associated with that setup. That will put it through its paces there, but won't help once it is in your car running on your controller, which will need to be tuned for the new engine.

Gotcha, that makes sense
I ended up with an RTD+ dongle instead of the mvi2, would they still be able to tune with that? I'm trying to avoid another 1k in credits

[StrokerAce]

you just don't update it.

I have 4 MPVI1 pros and 1 MPVI2 i use weekly lol. I don't tune vipers for a living just mine but i do GM late model LS and LT 5 days a week for years.
I have different cables for different uses. Hptuners keeps releasing new cables so you can't use it with new software but RE RE people always want to update every time something new comes out LOL.

By any chance, do you work for a specific shop?

[TBSH]

By any chance, do you work for a specific shop?

I work for myself
I Tune late model Ls and Gen5 LT cars/trucks all week every week of the year hahah. I just happen to own a viper and tuned it. Picked up .3 or so in the 60-130 from just tuning.

[Sniper]

My tuner said he verifies the WOT air/fuel ratio tuning it on the road.
They also have their own dyno so they will do a before and after dyno.

[StrokerAce]

I work for myself
I Tune late model Ls and Gen5 LT cars/trucks all week every week of the year hahah. I just happen to own a viper and tuned it. Picked up .3 or so in the 60-130 from just tuning.

Got ya. Just wasn't sure if that was your only job and you were hooked up with a big name shop.

[Docmartin]

How does that work considering he doesn't have my ecu and I currently have a tune for bolt ons?

- - - Updated - - -



It made a hell of a difference, 610-620 with just bolt ons

Not to derail the convo but what bolt ons are needed to get to this power?

[Mikey]

Not to derail the convo but what bolt ons are needed to get to this power?

All I had was intake, exhaust, high flows, and an underdrive pulley

[Gen5snake]

Knowing that our engines are naturally aspirated, how much power can be gained from stock...with respect to tune? I can't see it being much.....all these claims of all these gains on some of these dyno's aren't believable (anyone can screw with correction factors..eddy current). 1/4-mile times will tell all. I'd like to see time slips from a stock tune vs prefix vs HPtuners...consistent weather conditions. 20 real hp maybe? I can see the benefits of a custom tune if you have some serious work done, especially forced induction.

[StrokerAce]

With bolt ons? I'd wager a bit, not sure how much is left on the table with just a tune on a stock car but I've never seen a stock car not benefit from a custom tune. 20k isn't much but every little bit is a good thing. :)

[Mikey]

Knowing that our engines are naturally aspirated, how much power can be gained from stock...with respect to tune? I can't see it being much.....all these claims of all these gains on some of these dyno's aren't believable (anyone can screw with correction factors..eddy current). 1/4-mile times will tell all. I'd like to see time slips from a stock tune vs prefix vs HPtuners...consistent weather conditions. 20 real hp maybe? I can see the benefits of a custom tune if you have some serious work done, especially forced induction.

I believe @Venom-TA has a dyno sheet in hand. All he has is bolt ons and a tune

[VENOM-TA]

I believe @Venom-TA has a dyno sheet in hand. All he has is bolt ons and a tune
No dyno sheet.. this was told to me by seller and then verified by me calling Prospeed in Houston and getting the info..

[Steve M]

Knowing that our engines are naturally aspirated, how much power can be gained from stock...with respect to tune? I can't see it being much.....all these claims of all these gains on some of these dyno's aren't believable (anyone can screw with correction factors..eddy current). 1/4-mile times will tell all. I'd like to see time slips from a stock tune vs prefix vs HPtuners...consistent weather conditions. 20 real hp maybe? I can see the benefits of a custom tune if you have some serious work done, especially forced induction.

20 HP is probably a good conservative estimate.

There's more left on the table with the Gen 4 stock tune than there is with the Gen 5 stock tune from what I've seen with HPTuners. The Gen 5 has a little more timing in the main spark table, and doesn't pull timing quite as much as the Gen 4 tune does. I also suffered from some serious torque management issues where the car would not give me all the timing I was asking for - that took HPTuners adding a couple more tables to fix that one. The Gen 5 didn't seem to suffer from that same issue.

I never ran mine with the stock tune down the 1/4 mile, although I probably should have just to have the baseline. I do know at one point altering the tune so that my WOT AFR went from around 12.5:1 to 12.8-12.9:1, and that was good for about 1-1.5 MPH in the 1/4 mile with no other changes. That's about 10-15 HP at my race weight.

Fastest stock Gen 4 trap speed I've ever seen was 129.79 MPH with a DA of -915 ft. Mine with high flow cats, Gen 5 intake manifold, and HPTuners did 131.08 with a DA of +1,169 ft. Obviously not apples-to-apples, but the tune accounted for most of what it could do, and also made it very consistent regardless of DA. For example, my car trapped 130.02 MPH with a DA of +2,372 ft (~77 deg. F) mostly because I wouldn't let the PCM pull timing like it normally would have.

[Jack B]

It is fairly simple to install an Innovate air/fuel logger. In addition, your AF ratio changes from the dyno to real world full throttle. I would find 1/2-3/4 point diff, richer on the road during the top of full throttle 4th gear.

In addition, it is hard to get an accurate AF reading on the dyno, the AF snifffer is hard to get deep enough into the viper exhaust. If you can disable (via HPT) the PCM AF sensor input, have the dyno operator install their AF sensor in the oem sensor well. A lot of work, but, you will get a more accurate reading

[Mikey]

I called the local performance shop that works on high HP vehicles, they also don't like the stock ECM. Your best bet is Torrie, the ONLY issue with Torrie is that he will not turn off the 02 sensors if you have high flow cats.


Edit: stock 2014 TA with a tune

52456

[Old School]

Even though I don't like the idea of having to connect to HPtuners servers in order to reflash, I am satisfied with their product. It is straight forward to edit the engine controllers' parameters and the logging feature works well.

[Jack B]

Even though I don't like the idea of having to connect to HPtuners servers in order to reflash, I am satisfied with their product. It is straight forward to edit the engine controllers' parameters and the logging feature works well.

Unless something has changed, the logging is limited. In the past, HPT would not show misfire PIDS or Knock Pids, both are important in tuning. These PIDS were available on the G4, but, not on the G5.

The gray market Witechs, will show/record all.

[Old School]

Unless something has changed, the logging is limited. In the past, HPT would not show misfire PIDS or Knock Pids, both are important in tuning. These PIDS were available on the G4, but, not on the G5.

The gray market Witechs, will show/record all.

I had a couple of things that didn't work with mine, I opened a "ticket" on their websight and they were corrected in a beta release.

[CNU_Physics]

What do you mean won't turn off the O2 sensors? As in the emissions light? Or completely turn off the Narrowband O2's from calculating fuel?

[nwa_viper]

What do you mean won't turn off the O2 sensors? As in the emissions light? Or completely turn off the Narrowband O2's from calculating fuel?

I would assume turning off the rear O2 sensors to avoid the check engine light for catalyst efficiency.

[CNU_Physics]

Oh the post-Catalytic converter O2's you mean?

In HPTuners you can go into the Diagnostic Trouble Code list and set the Catalyst Efficiency SEL to Enabled, or whatever the name is in HPTuners, and it will always pass emissions. Even if the battery is disconnected or PCM is reset, etc. Does the same thing.

[Dan Cragin]

HP is very limited in what you can change. Prefix uses the factory stuff to do the computers.
Understand that an engine tuned to the lean limit and with aggressive timing will make the best power, but
engine life will be reduced.

Always best to have a smog and race computer. The writing is on the wall when it comes to smog now.