Misfires with JB4 Map 7 - DIY Plug Swap?

[bmeaggie]

All-

Every time I try to use JB4 Map 7 with <30% ETOH I struggle with Misfires at high RPM. Car only has 4000 miles on it, and works like a champ in all other scenarios. I make my mix with pump 93 octane and pump e85 (about 4 gal e85 with balance if tank filled with the 93. This only happens with the ETOH% kicked up by adding the e85.

I will order a new set of OEM plugs and gap them at .020-.018 per Terry@BMS's instructions. I believe BMS also had this issue with their shop car and this is how they corrected it.

The only thing left is to find A DIY for the plug swap. I searched the forum and can't find one.

Any direction would be appreciated. Thank you!

[DREW@SUPREMEPOWER]

What is your fuel open loop set at?

[bmeaggie]

Originally Posted by DREW@SUPREMEPOWER

What is your fuel open loop set at?

70

[EALm4]

+1 on DIY plug swap tutorial

[RSXDC5]

Had the same problems as you, OP. This is how you solve it...

For everyone having hesitation issues using e85 blends...do a half throttle 4th gear pull, the jb4 can adjust to your e85 blend then. After, do a full throttle run, if it still hesitates, do another part throttle 4th gear pull. Everything should be adjusted now.

For your first legit full throttle gear pull, you probably won't be able to hit optimal timing advance, but the next pull u should hit optimal timing advance, or something close to it!

Enjoy!

[mark5092]

Did Terry recommend the NGK 4786 plugs? Are they a colder plug than stock plugs?

[mark5092]

Originally Posted by bmeaggie

All-

Every time I try to use JB4 Map 7 with <30% ETOH I struggle with Misfires at high RPM. Car only has 4000 miles on it, and works like a champ in all other scenarios. I make my mix with pump 93 octane and pump e85 (about 4 gal e85 with balance if tank filled with the 93. This only happens with the ETOH% kicked up by adding the e85.

I just ordered a set of NGK 4786 and will gap them at .020 per Terry@BMS's instructions. I believe BMS also had this issue with their shop car and this is how they corrected it.

The only thing left is to find A DIY for the plug swap. I searched the forum and can't find one.

Any direction would be appreciated. Thank you!

Have you ever misfired with tank of 93 using map 2?

[bmeaggie]

Originally Posted by mark5092

Have you ever misfired with tank of 93 using map 2?

No. Only with e85.

[bmeaggie]

Originally Posted by mark5092

Did Terry recommend the NGK 4786 plugs? Are they a colder plug than stock plugs?

Yes. This is the plug he discussed using on N54tech.

[Mike@N54Tuning.com]

BMS does not suggest those plugs. They do not work. Run only OEM plugs gapped down to. 018 to. 020

Mike

[AM4ZING]

Originally Posted by RSXDC5

Had the same problems as you, OP. This is how you solve it...

For everyone having hesitation issues using e85 blends...do a half throttle 4th gear pull, the jb4 can adjust to your e85 blend then. After, do a full throttle run, if it still hesitates, do another part throttle 4th gear pull. Everything should be adjusted now.

For your first legit full throttle gear pull, you probably won't be able to hit optimal timing advance, but the next pull u should hit optimal timing advance, or something close to it!

Enjoy!

Thanks for this... Im going to give it a try as i also experience sputtering on E85 at high rpms

[RSXDC5]

Originally Posted by AM4ZING

Thanks for this... Im going to give it a try as i also experience sputtering on E85 at high rpms

NP, also keep in mind that the "procedure" you will be performing only holds until you switch maps, once you switch it would need to be performed again.

Filling up with a new tank of E85/91oct will most likely have a new exact E85 blend and my require a "re-calibration" again

[A Frankfurt]

You do have the waste gate connections installed right ?
Those are needed for Map 6 and above per Terry @ BMS

[mark5092]

Originally Posted by Mike@N54Tuning.com

BMS does not suggest those plugs. They do not work. Run only OEM plugs gapped down to. 018 to. 020

Mike

That's what I thought. Must be very careful gapping factory plugs, they damage easily. They seem to all come pre gapped at .028

[bmeaggie]

Originally Posted by A Frankfurt

You do have the waste gate connections installed right ?
Those are needed for Map 6 and above per Terry @ BMS

I have all connections and car is basically new.

All works perfect until I try the 85% blended in.

The facts point to a combustion issue with the higher ethanol %. Just need to find the needed tweak.

[bmeaggie]

Originally Posted by RSXDC5

Had the same problems as you, OP. This is how you solve it...

For everyone having hesitation issues using e85 blends...do a half throttle 4th gear pull, the jb4 can adjust to your e85 blend then. After, do a full throttle run, if it still hesitates, do another part throttle 4th gear pull. Everything should be adjusted now.

For your first legit full throttle gear pull, you probably won't be able to hit optimal timing advance, but the next pull u should hit optimal timing advance, or something close to it!

Enjoy!

So to be clear, are you saying to do these pulls to readline?

Also do we do the pulls in Map 7?

[RSXDC5]

Originally Posted by bmeaggie

So to be clear, are you saying to do these pulls to readline?

Also do we do the pulls in Map 7?

As high as you rev while doing the pulls will be as high as the stuttering will not occur.

Switching maps resets what you are doing, so do pulls in the map you want adjusted to your e85 blend. everything resets when you switch maps.

[A Frankfurt]

Originally Posted by bmeaggie

I have all connections and car is basically new.

All works perfect until I try the 85% blended in.

The facts point to a combustion issue with the higher ethanol %. Just need to find the needed tweak.

http://www.n54tech.com/forums/showthread.php?t=25401

Here it states that if there are issues in Map 7 you need to change back to Map 2.
You should do a log and contact Terry @ BMS and get his input.
For some reason, some S55's have issues with fuel pressure drop with Map 7 depending on the amount of E85 or higher octane fuel and need to make adjustment's and or change the map.

[mike@x-ph.com]

Originally Posted by A Frankfurt

http://www.n54tech.com/forums/showthread.php?t=25401

Here it states that if there are issues in Map 7 you need to change back to Map 2.
You should do a log and contact Terry @ BMS and get his input.
For some reason, some S55's have issues with fuel pressure drop with Map 7 depending on the amount of E85 or higher octane fuel and need to make adjustment's and or change the map.

+1

Here is exactly what it says about map 7
Map 7: Race gas map. Requires 100 octane unleaded fuel and for the fuel mass connector to be installed. Can be used with or without the EWG connectors but will make more power with the EWG connectors installed. This map can also be used with up to 35% E85 but in some vehicles & conditions this may cause a high fuel pressure drop and resulting stuttering. If this occurs drop down to map 2.

[bmeaggie]

Originally Posted by Mike@N54Tuning.com

BMS does not suggest those plugs. They do not work. Run only OEM plugs gapped down to. 018 to. 020

Mike

You are correct Mike. Terry just chimed in on his site. BMS says to stick with the OEM plugs and gap them to .020 down to .018.

[bmeaggie]

Originally Posted by mark5092

Did Terry recommend the NGK 4786 plugs? Are they a colder plug than stock plugs?

I was wrong apparently. BMS just told me to stick with OEM plugs, and gap them .020 - .018.

[dmk08]

I always just run Map 2 w/ 4 gallons of e85 and the rest 93 octane. How much faster is Map 7 vs this? I have never tried it. Scared to shred my crank hub lol

The E85 mix makes a huge difference from strait 93 on map 2. Much smoother and tire frying.