[N54Society]

I recently purchased this car and the previous owner claimed that there is a Giac tune. Other than his word, I don't really have any way of knowing if it has it or not. I have not found anything online which would show how Giac is installed. Anyone know where I can start looking?

Thanks!

[ard5040]

If you call GIAC and give them the vin # they should be able to tell you if you have their software installed or not. They keep records because their software has to be reinstalled if a dealer ever updates your ecu. That, by the way, is the the only way to delete the software if you ever decide to move on to something else.

[csu87]

Originally Posted by ard5040

If you call GIAC and give them the vin # they should be able to tell you if you have their software installed or not. They keep records because their software has to be reinstalled if a dealer ever updates your ecu. That, by the way, is the the only way to delete the software if you ever decide to move on to something else.

pretty sure the MHD can flash over it, and Im sure a cobb could do the same.

[N54Society]

Can the JB4 G5 be flashed over GIAC?

Thanks!

[Antetokounmpo]

Originally Posted by vbp6us

Can the JB4 G5 be flashed over GIAC?

Thanks!

Jb4 is not a flash. It's a piggyback. MHD is a flash tune that will replace giac. You also should be able to download the mhd app and it should say the ecu flash name under info if i remember correctly, it might say giac or something.

[N54Society]

I emailed the guys over at GIAC to see if they can verify that my car was tuned. Let's see what they say. If they say they have no record for the tune, is there any harm in trying to hook up the JB4 and firing it up?

[Antetokounmpo]

Originally Posted by vbp6us

I emailed the guys over at GIAC to see if they can verify that my car was tuned. Let's see what they say. If they say they have no record for the tune, is there any harm in trying to hook up the JB4 and firing it up?

Won't be an issue. Take logs once you do, we'll be able to tell from them if it is indeed flashed.

[N54Society]

Originally Posted by bk335

Won't be an issue. Take logs once you do, we'll be able to tell from them if it is indeed flashed.

Just got an email back from them saying that they have no record of the VIN in their database. This is good and bad for me of course. The information about the tune isn't from the owner. The owner's boyfriend sold the car for her and her ex-husband was the one that supposedly got the GIAC. No receipts to support the claim either. I'm thinking it was a miscommunication or a straight up lie.

I just bought a JB4 G5 last night too. I hope I don't have to put it up for sale.

Thank you so much for your help!

[Antetokounmpo]

Originally Posted by vbp6us

Just got an email back from them saying that they have no record of the VIN in their database. This is good and bad for me of course. The information about the tune isn't from the owner. The owner's boyfriend sold the car for her and her ex-husband was the one that supposedly got the GIAC. No receipts to support the claim either. I'm thinking it was a miscommunication or a straight up lie.

I just bought a JB4 G5 last night too. I hope I don't have to put it up for sale.

Thank you so much for your help!

Why would you need to sell the jb4?

[N54Society]

Originally Posted by bk335

Why would you need to sell the jb4?

Maybe I'm confused but if it does actually have a GIAC tune, will the JB4 work? Will it overwrite the values assigned by GIAC as it passes through the JB4 harness?

Unlike a flash, a piggy back can be undone by simply unplugging it, right?

[ard5040]

Originally Posted by csu87

pretty sure the MHD can flash over it, and Im sure a cobb could do the same.

I tried flashing over my GIAC tune with the Cobb v3 when I got ready to upgrade my turbos about a month ago. Wouldn't do it. Called GIAC , they told me it had to be deleted first.

[Antetokounmpo]

Originally Posted by vbp6us

Maybe I'm confused but if it does actually have a GIAC tune, will the JB4 work? Will it overwrite the values assigned by GIAC as it passes through the JB4 harness?

Unlike a flash, a piggy back can be undone by simply unplugging it, right?

JB4 basically tricks the ECU by telling it it's still only running 8psi max of boost, even though it may be running 18psi or so. The GIAC tune is similar to Dinan where it tells the ecu to make more boost. So yes, the JB4 will work over the GIAC, though it won't be ideal. I'd highly recommend a BMS backend flash through MHD OR just flash a ecu flash through MHD (stage 1 93 or 91 or something). The backend will be about $100, $70 for app flashing license and $25 cable, the flashes are free by Terry on n54tech. The MHD flashes are like $50 or so.

I realize that might be confusing if you're not familiar to the terms so I'll break it down.

Present
ECU flash - GIAC (maybe)
Piggyback - none

Option 1 (recommended)
ECU flash - BMS backend pump flash
Piggyback tune - JB4

Option 2
ECU flash - MHD stage 1
Piggyback - none

Option 3
ECU flash - GIAC or stock
Piggyback tune - JB4

Hope this helps.

[fazman]

Originally Posted by vbp6us

I recently purchased this car and the previous owner claimed that there is a Giac tune. Other than his word, I don't really have any way of knowing if it has it or not. I have not found anything online which would show how Giac is installed. Anyone know where I can start looking?

Thanks!

jb4 is better, don't worry if u have that Giac-arbage... just install the JB4 and do the free jb4 backend flash and call it a day. you will never look back in regret and will have a permanent smile on you face as your driving everyday.

[N54Society]

Originally Posted by bk335

JB4 basically tricks the ECU by telling it it's still only running 8psi max of boost, even though it may be running 18psi or so. The GIAC tune is similar to Dinan where it tells the ecu to make more boost. So yes, the JB4 will work over the GIAC, though it won't be ideal. I'd highly recommend a BMS backend flash through MHD OR just flash a ecu flash through MHD (stage 1 93 or 91 or something). The backend will be about $100, $70 for app flashing license and $25 cable, the flashes are free by Terry on n54tech. The MHD flashes are like $50 or so.

I realize that might be confusing if you're not familiar to the terms so I'll break it down.

Present
ECU flash - GIAC (maybe)
Piggyback - none

Option 1 (recommended)
ECU flash - BMS backend pump flash
Piggyback tune - JB4

Option 2
ECU flash - MHD stage 1
Piggyback - none

Option 3
ECU flash - GIAC or stock
Piggyback tune - JB4

Hope this helps.

Thank you for explaining all of that. Could you elaborate on the BMS backend tune? Is it a stock 335i tune meant to run on 91? Links to the cable and the BMS backend flash? I couldn't find anything for the cable that was less than $179.

[Antetokounmpo]

Originally Posted by vbp6us

Thank you for explaining all of that. Could you elaborate on the BMS backend tune? Is it a stock 335i tune meant to run on 91? Links to the cable and the BMS backend flash? I couldn't find anything for the cable that was less than $179.

The BMS backend flash is an ecu flash that controls everything the GIAC controls except boost. It leaves JB4 to do that so it makes switching maps incredibly easy, only a few steering wheel button presses. The JB4 alone can't control timing and fuel, etc., that up to the DME, but with a backend flash, the DME is now aware it's running more boost and can run the engine to it's full potential. The stock 335i tune is for 91 minimum. The BMS pump flash is for either 91 or 93 and raises the boost in maps 1 and 2 to 15 and 17psi respectively. Without it, your car will probably only be able to run map 1, 13psi (because no backend flash) because the DME will pull a lot of timing. The pump flash fixes this and you can usually run 15psi on 91 and 17psi on 93. Throw some E30 in and run map 5 and you should hit 18psi.

MHD backend JB4 flashes: http://www.n54tech.com/forums/showthread.php?t=29236

You only need a K+DCAN cable for MHD like this one: http://www.amazon.com/KCRIUS-TM-Inte...eywords=k+dcan

Also, MHD is very cable-sensitive per se so it may take one or two before you find one that works. I used the one linked above and it worked great.

[N54Society]

Originally Posted by bk335

The BMS backend flash is an ecu flash that controls everything the GIAC controls except boost. It leaves JB4 to do that so it makes switching maps incredibly easy, only a few steering wheel button presses. The JB4 alone can't control timing and fuel, etc., that up to the DME, but with a backend flash, the DME is now aware it's running more boost and can run the engine to it's full potential. The stock 335i tune is for 91 minimum. The BMS pump flash is for either 91 or 93 and raises the boost in maps 1 and 2 to 15 and 17psi respectively. Without it, your car will probably only be able to run map 1, 13psi (because no backend flash) because the DME will pull a lot of timing. The pump flash fixes this and you can usually run 15psi on 91 and 17psi on 93. Throw some E30 in and run map 5 and you should hit 18psi.

MHD backend JB4 flashes: http://www.n54tech.com/forums/showthread.php?t=29236

You only need a K+DCAN cable for MHD like this one: http://www.amazon.com/KCRIUS-TM-Inte...eywords=k+dcan

Also, MHD is very cable-sensitive per se so it may take one or two before you find one that works. I used the one linked above and it worked great.

I don't know how I can repay you for this amazing information. Thank you.

[N54Society]

Originally Posted by ard5040

I tried flashing over my GIAC tune with the Cobb v3 when I got ready to upgrade my turbos about a month ago. Wouldn't do it. Called GIAC , they told me it had to be deleted first.

Anyone know why this was the case?