MustangForums.com - Will headers cause a car to run lean?

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RE: Will headers cause a car to run lean?

any thoughts on why my car gets the hickups if it sits a few days...?

RE: Will headers cause a car to run lean?

I plan on getting cams by the end of the summer. I dont want to spend $500 on a tune until I get cams. Unfortunately, the place that knows mustangs around here charges $300 for the first time of tuning plus $200 for the tune. I dont really know why there is that $300 charge, but I might look at a few more shops before I have it tuned to see if anywhere else is a little bit cheaper. MC racing is the name of the shop btw if anybody has heard of it.

RE: Will headers cause a car to run lean?

Quote:

ORIGINAL: xxkazp3rxx

The only thing im adding to this.. is this... I am not talking about my experiances with my Cobra. I am referring to things about a 2v, if you remember - I had a 2004 GT - that included LT headers... and I was also using a close friends 03' GT as a personal example without saying it - He had my setup almost exactly - minus tune. He needed a new motor because he was running much to lean, and it popped - he gave me a nice laundry list of things that went wrong. The A/F was in the 15's I believe.. I'd have to ask him when I see him, if he remembers... Again, I never said it happens a lot, but it does happen - that's it. 2000, I respect your opinion on here, and it shows you know what you're talking about - but i think sometimes you forget about the exceptions to the rule. By rule - you're right, but rules are made to be broken.

I stand by my point, that headers are one of the last things i'd do. Honestly, because cams NEED a tune, I would probably do headers + cams at the same time, but not before I put in a better clutch and made sure my tranny was ok... well that's assuming you want to do cams...

I am sorry, but there must have been another problem w/ your friends car to cause it to blow. Running a 15:1 A/F ratio on a n/a 2v gt will not cause the engine to blow.

It could have been anything, a loss of oil pressure, overrev, anything, but his LT headers didn't cause the engine to blow up.

RE: Will headers cause a car to run lean?

2000 - you're not reading what im saying - im not saying LT headers did, or will do it. Very well could've been something else wrong. I just know that the Ford mechanic, and the Speed shop he took it to both said it was because of a lean a/f mixture (Ford still covered it, so don't say they were trying to weasle out of covering it). I just know what im told man, lol - i'll be really honest - I know nothing about interiors of the engines, and little about what is to lean/rich. but you're not reading, and we all know you can read. I never once said that Longtube headers will hurt your car. What i've been saying is about the tune and the A/F mixture. That a car being to lean obviously can hurt your car, and being to rich can too. Which it can. I don't know why you're dragging this on still, it's like beating a dead horse. I say things, and you just ignore what I say and come back with something that's totally irrelevant to what I had previously said. The orginal topic was about headers making the car lean, if anything we've already established that if anything it'd run rich - which can be bad for the motor and performance, as you're leaving horsepower on the table with a rich tune. Again, im done with this topic, enjoy arguing a point that nobody has brought up. You've proved yourself right, against yourself... nice waste of energy, and even bigger one that im still looking at this thread.

RE: Will headers cause a car to run lean?

the point is that none of the boltons will cause the car to go lean or rich enough to acutally damage the car. That, and a n/a 2v will have to be WAY off to acutally damage the engine. So far off that it would simply run like total ass, ping like crazy, all things you would immediatly notice (well before damage occured)

How the hell did the ford tech even know what the a/f ratio was? He was just blowing smoke up your friends ass. The engine is already blown, and he is telling you its leaned out at xx a/f ratio? Hell, the ford shops cannot even check the a/f ratio anyway.

Your friend just got unlucky and had something else go wrong, or a bad motor to start with. His a/f ratio being at 15:1 did not destroy the engine. Hell, there are plenty of cars that come out of the factory running 14.2:1 or leaner.....