Should I start it? Or tow it to tuner?
03-30-2018 | 11:21 AM
#1
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Joined: Aug 2006
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From: Hamlin ny
Should I start it? Or tow it to tuner? Here’s my situation, got an lq4 at the shop being rebuilt at the shop replacing my 5.7 that went, my 5.7 had a tsp v3 cam prc 2.5 ls6 heads and ls6 intake with #40lb injectors. I have a custom cam specd by pat g for the lq4 and is a lot bigger than the tsp v3 cam. I’m reusing the prc heads Intake and injectors only thing changing is obv motor size and the cam but the tune that’s still on the car for the 5.7 was GARBAGE, car bogged at low speeds and had lean issues. When I tore the 5.7 down 3 spark plugs were all white on the tops. Being that im swapping in a fresh rebuilt motor and needs to break in properly should I even risk starting it up with that tune or just tow it to my tuner? And can they even tune it that day or does the motor have to be broken in first?
03-30-2018 | 12:33 PM
#2
I would up load a start up tune from where you will get you car tuned from and then have it towed to the location since the tune will not be perfect.
That way with the start up tune you can at least start up the vehicle and make sure you dont have any leaks or problems when you actully go get a tune. That way you can prevent any problems.
That way with the start up tune you can at least start up the vehicle and make sure you dont have any leaks or problems when you actully go get a tune. That way you can prevent any problems.
03-30-2018 | 12:34 PM
#3
If your asking the question you know the answer. If the tune was really far off a fresh motor wouldn’t appreciate that particularly as it’s breaking in. Granted nothing is spot on after a rebuild but generally you want it in the ballpark. I’m sure your tuner if he’s any good has a base he would start from
03-30-2018 | 09:39 PM
#4
You're not going to damage anything by starting it or even driving it. The computer uses the 02 sensors to try and get the fueling as close to stoich as possible. The farther you are from factory baseline with the cam, the harder it has to work to achieve it. So you'll get sputtering and stalling at worst.
Now, if you start flooring it; the computer uses baseline assumptions without any input from sensors. You can achieve lean conditions under that scenario which is obviously what you want to avoid.
Now, if you start flooring it; the computer uses baseline assumptions without any input from sensors. You can achieve lean conditions under that scenario which is obviously what you want to avoid.
03-31-2018 | 09:04 AM
#5
You're not going to damage anything by starting it or even driving it. The computer uses the 02 sensors to try and get the fueling as close to stoich as possible. The farther you are from factory baseline with the cam, the harder it has to work to achieve it. So you'll get sputtering and stalling at worst.
Now, if you start flooring it; the computer uses baseline assumptions without any input from sensors. You can achieve lean conditions under that scenario which is obviously what you want to avoid.
Now, if you start flooring it; the computer uses baseline assumptions without any input from sensors. You can achieve lean conditions under that scenario which is obviously what you want to avoid.
03-31-2018 | 01:47 PM
#6
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From: Hamlin ny
I'm no tuner, but this is my understanding as well. It's the open loop versus closed loop operation of the ECU. As long as you use the same injectors from the original tune, and the original tune isn't complete trash, it won't harm the engine to run it at idle and with limited RPM and throttle opening.
03-31-2018 | 02:47 PM
#7
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Joined: Jul 2007
Posts: 967
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From: Winter Haven FL
The tune was bad and ran lean. Now you're increasing displacement on the same tune that didn't give enough fuel before. My question would be why risk a new engine when you know you're going to get it tuned anyway.
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04-01-2018 | 08:36 AM
#8
It’s best to be able to do some pulls at or near WOT, but it’s not going to hurt the engine if you can’t. I broke in my last engine by driving it from my house in Houston to my tuner’s shop in Victoria.
04-01-2018 | 12:11 PM
#9
You have some ***** to do that. I couldn't have done that. That's a 3-4 hour drive for you.