How do I disable the boost/fuel hard limit? I installed twin GFB atomic MBC's & the motor hits a hard limiter at 0.8 Bar. I don't want to go much higher as this TT 2+2 JDM will be kept mainly stock. It's more a safety concern for fast overtaking. Whatever is the cheapest/fastest fix is fine. I have full NissanDataScan & Conzult tuner, but see no option in the menu there.
What do you mean hits a limiter? There's a factory speed cut but no factory boost signal related cut... Around 1 bar is perfect for a stock car.
There is a fuel cut in the tune, but it's so far up there it won't be causing the issues you have. Read the nistune tuning guide, details it all. Something else is going on. You checked the error codes?
Frequency issue? May well be unrelated , My car once had a similar issue after installing a pod filter , turned out to be a frequency issue with the AFM , I confirmed this by duct taping half of the pod , then for a permanent fix I made up a large perforated aluminum box which the afm/pod sat in side , may not be this but easy enough to rule out ,
I don't have nistune as far as I known. Also no error codes. (55) By 'hard limiter' I mean the fuel supply is completely cut till boost falls below 0.8 Bar again. (There's a big difference between 0.8 Bar & 1 Bar boost). Conzult shows speed is limited at 330km & rpm at 8,400. Normally I'd just run a dedicated 12 volt supply to the fuel pump to bypass, but can't with the variable fuel pump power supply.
Sounds like you have an aftermarket chip. The rev and speed limits are way higher than stock. Might be an idea to swap a standard ECU back in and see if that fixes it.
This Z does have a pod filter on it. I was going to swap back in the OEM set-up from my NA 2+0 Z. I'm not a real fan of pod filters unless they are in a box. Air-box slows the air down & makes it more dense. Also some AMM's (or AFM) need a 90* bend pipe going to them (or similar) or they read incorrectly.
Maybe, but a don't have a spare TT one. $300 for cheapest ECU on ebay. Think I'd try reprogramming before that.
Got any mates nearby? Can't see nistune costing less than $300 and you don't know if the ECU is the issue
Stuff me; the problem was the PTU! Swapped in the PTU from my NA Z & it boosted straight up to 1 Bar. I've ordered 2 new PTU S2's for both my Z's & have relocated the present ones to the nose cone area. Relocating them alone made a big difference to engine performance.
