JLT Intake Problems

[jakesmithpbr]

I have a 2007 mustang gt with headers and a JLT intake. I installed the JLT intake last night and found the "correct" transfer function on a forum on here and the car ran really rough, had bogging problems. When I floor it, it feels like I lost power and falls flat on its face around 2.5k-3k RPM's. The only stuff I have in my tune is stuff that Eric suggested in his How-To guide. Fuel trims are really really rich. It also goes into open loop 5 seconds or so while deceling and starts popping. Pretty confused. Any thoughts? Or is there anything else specific I need to do when installing the JLT intake that I am missing?

[rryanfla]

My 2cents. I believe it goes into OL when decel fuel kick in. As far as you JLT start pulling fuel from transfer function by half then half then half until you get in the 5% trim. Disable ltft and any fuel adders to dial it in. I just installed a JLT on my tvs 17 and transfer was really lean, spent 3 hours on dyno dialing it in. Took about 15% more fuel then my Roush intake. Hope it helps

[jakesmithpbr]

My 2cents. I believe it goes into OL when decel fuel kick in. As far as you JLT start pulling fuel from transfer function by half then half then half until you get in the 5% trim. Disable ltft and any fuel adders to dial it in. I just installed a JLT on my tvs 17 and transfer was really lean, spent 3 hours on dyno dialing it in. Took about 15% more fuel then my Roush intake. Hope it helps

Turned off LTFT and didn't do anything.
I pulled a transfer function from this thread https://forum.hptuners.com/showthrea...ang-GT-JLT-CAI and it was saying it was extremely rich. This is the function I've been trying to tune with and trim fuel. I looked more and found a completely different transfer function on this forum https://forum.hptuners.com/showthrea...-Maf-Transfert

I'm going to try that function tomorrow... Seems like REALLY high numbers but I'm willing to try anything at this point. Tired of my car running sub-par. I feel like I should see a more significant increase in horsepower. I have headers and an intake. Doesn't feel as bad as stock but it doesn't feel like it's at the point it should be at.

[JuiceNA]

You got the wrong transfer function for your intake. It should not be that rich. (Or there are other problems in addition)

I have a JLT2 intake and got the transfer function directly from jlt tech support. It is roughly 10% rich and I end up with negative 10% fuel trims. On an otherwise 100% factory stock down to the stock headers w/cats engine.

[rryanfla]

[email protected]. Email him and tell him what you have and he will email you the transfer function...

[CCS86]

JLT isn't qualified to be making MAF housings.

They are selling uncalibrated plastic tubes for hundreds of dollars and taking the stance that "your tuner should be able to figure out the transfer function, or they are a shitty tuner". Morons.

If you email Vinny, he will send you a transfer function, made up of random garbage that some random unqualified shop hacked together. Like this:

JLT trash curve.jpg

[CCS86]

Oh, here's another gem that they sent me, compared to proper MAF curves:

JLT Trash 2.jpg

Quit giving these hacks your business. If you can't flow bench MAF housings, you shouldn't design and manufacture them.

[jakesmithpbr]

You got the wrong transfer function for your intake. It should not be that rich. (Or there are other problems in addition)

I have a JLT2 intake and got the transfer function directly from jlt tech support. It is roughly 10% rich and I end up with negative 10% fuel trims. On an otherwise 100% factory stock down to the stock headers w/cats engine.

Mine may be different because I have headers and no cats, not sure. With the transfer function that has 58.815 #/min @ 5V EVERY cell was above positive 25 fuel trims, there we no negative fuel trims what so ever. Ever since I installed the headers I've had problems with my car running rough.

[jakesmithpbr]

Oh, here's another gem that they sent me, compared to proper MAF curves:

JLT Trash 2.jpg

Quit giving these hacks your business. If you can't flow bench MAF housings, you shouldn't design and manufacture them.

Lol makes sense. Before my JLT intake I had a 100mm ebay intake and all i did was multiply my stock MAF values by 30% and I had it running better than my car is with a BRAND NAME intake and "Known good" transfer function. Kind of sucks how little information there is on tuning 3V modular engines. Most info that's actually out there is done in old versions of VCM editor and barely applies anymore. Where the gurus at?

[SultanHassanMasTuning]

post your file, also if you did not adjust your multipliers it will be lean

[jakesmithpbr]

post your file, also if you did not adjust your multipliers it will be lean

Here's my file https://easyupload.io/2evyhk

I changed some stuff around last night so I can test it out this morning. Especially the MAF table. Here is the table while it was running OK but still a WOT it would fall completely on its face, barely any power. https://easyupload.io/rm88gy\

Let me know what you think. Definitely not a completely dialed in tune. Thanks

[jakesmithpbr]

Well I ended up trying that one with 83 #/min at 5v and thought i blew my car up. Wrench light came on, wouldn't start, no sounds but just wouldn't idle. Had to unplug the MAF sensor to drive it home. Starting a new tune from scratch now. Sketch