LT1 to LT4 conversion TMAP settings and throttle issues

[Everlast]

I have read through the forum on this topic and i have found the settings to be NA TIAP with the lt1 to lt4 breakout harness to the TMAP and MAF sensor. What information I have found on here states that IAT2 sensor data should be the same as IAT and they should be setup to be like the LT4. I read the MAP estimation to be set as 255 max and 10 min and that MAP linear to be set as 425 and offset to be -32.5. This being the case and i have double checked all the connections and the data is being shown on hp tuners I am still having an issue when i go beyond 20%ish throttle or WOT the car falling on its face and hesitation.

I read in previous older post that you all were running the ZR1 3 bar map sensor and using a breakout wire for the IAT2 reading. The car is great on just going along at small throttle and cranking but when the throttle is pushed beyond the threshold it simply goes crazy. I found that someone had mentioned the parameters/ecm needs reset before any flashing but I haven't found what option that is or if that truly is the solution to my problem. I appreciate any help or if there is something small that needs set that is different entirely from the ZL1/Z06 other than the SCIAP setting/sensor not being there when using the TMAP breakout harness on the LT1.

[Pekka_Perkeles]

How about torque management / demand?

Post your tune and logs.

[davispaintandbody]

did you ever get it figured out ?

[RoninDusette]

I have the same problem and it turned out to be that we accidentally had a one bar map sensor on the back of the supercharger. So every time we get anywhere near or over like 101 kPa it would just fall on its face exactly like you're saying it would backfire and you know basically boost cut and just kind of fall on his face. So I just double check the part number and make sure that it's actually a three-bar map sensor and that you have it wired correctly. And that you also have a 1 bar map and the IAT broke out of the mass air flow sensor. You can leave the one bar map just kind of like like the tight or something underneath the intake manifold it can just read pure air you don't want it reading vacuum or anything from inside the motor. But other than that as long as that rear map is good you shouldn't even need the throttle inlet pressure sensor you just need that three bar map in the back and you can even use a block off plate for the throttle inlet sensor unless you're using that the top for intake air temp

[GHuggins]

I have the same problem and it turned out to be that we accidentally had a one bar map sensor on the back of the supercharger. So every time we get anywhere near or over like 101 kPa it would just fall on its face exactly like you're saying it would backfire and you know basically boost cut and just kind of fall on his face. So I just double check the part number and make sure that it's actually a three-bar map sensor and that you have it wired correctly. And that you also have a 1 bar map and the IAT broke out of the mass air flow sensor. You can leave the one bar map just kind of like like the tight or something underneath the intake manifold it can just read pure air you don't want it reading vacuum or anything from inside the motor. But other than that as long as that rear map is good you shouldn't even need the throttle inlet pressure sensor you just need that three bar map in the back and you can even use a block off plate for the throttle inlet sensor unless you're using that the top for intake air temp

This is an old thread, but why not just set it up like the factory setup? Use the lt4 map. Wire the temp sensor and sciap into the ECM leaving the MAF input alone then set the calibration up accordingly?

[RoninDusette]

That's what I did do. I pulled the the barometric pressure sensor wire from the mass air flow sensor cuz you don't want to have heavy vacuum on that you want to read actual barometric pressure not vacuum and a supercharged vehicle and a good intake or any intake it's going to pull vacuum then you don't want that. So that's just like chilling underneath the intake manifold so it could read actual barometric pressure and it reads it just fine. The intake air temperature sensor I haven't broken out from the mass air flow sensor yet but if it becomes an issue that I will break it out to the tmap, and the manifold absolute pressure sensor the three bar one is at the back of the supercharger and the factory position with the calibration setup for a three-bar map sensor and then we're blocking off the throttle inlet air pressure sensor just because we don't need it at the moment and there's a lot of people that run it like that successfully. Again if it becomes an issue we can always put one in but I don't you know see an issue with doing that right now the plus the throttle in the air pressure sensor isn't going to reboost because it's before the screws

[GHuggins]

You can actually set the cars up to be just like factory boosted cars. That's what I meant. You have to wire in the sciap and third temp sensor. Everything except for step by step wiring instructions is posted here - https://forum.hptuners.com/showthrea...kground-Tables

Also something else I forgot to put in the write up that I'm going to need to correct. If you have a car, you have to request the sciap settings too. They're 0ed out from factory in the calibrations.

[RoninDusette]

So the third temp sensor in the supercharger manifold pressure sensor that's mandatory because I've seen other people run it a number of times where they're just running a barrel sensor and they're running the three bar four wire map sensor at the back of the supercharger with the throttle inlet pressure sensor Port plugged up.

[GHuggins]

If you want full functional throttle control then yes wiring in the temperature sensor, sciap and lt4's map sensor needs to be done. Cars are a whole other ball game than trucks. If the blower is small enough you can get away with all sorts of things on cars. Put a big blower in the equation and now cars throttles become uncontrollable just like trucks. I've personally done just like you and run a 3bar map and tuned even fifth gen trucks to be what I considered acceptable, but those were the older smaller blowers. These newer blowers just seem to keep getting bigger and bigger requiring the calibrations to actually be setup for boost like a factory calibration is