General performance mods.

[WhiteCrane]

I'm a newbie to engine mods. All I know about cars is what I can read in car and driver and learn from watching top gear. I have a general understanding of how things work though.

I am just curious now though as to what advantage some of the lower cost mods have on an engine. The reason I;m asking you guys is because no company that builds the arts will commit to how much HP you get from adding them.

Say you put new headers, + full exhaust on a good V8, without a tune. Don't wanna void the warranty. That do anything for ya? Or are we talkin' 10 horsepower? I already have a CAI.

Let's say you added a manifold on there. Any difference?

[Zabo]

From my understanding putting headers and/or a full exhaust are mostly an audio enhancement to the engine; allows a more visceral note to make it through the entire exhaust. Changing a throttlebody, manifold, intake 'elbow' can gain airflow in the engine on various levels depending on the geometry and size of the opening you allow the engine to draw air through.

Similar concept in a CAI, where the colder air actually creates a more 'preferable' charge of air when the engine goes suck, squeeze, bang, blow.

Porting and polishing the heads from my understanding also follows this line, but also creates a 'combustion' friendly situation where the actual cylinder head is changed to allow a more 'fuller' burn of the fuel/air charge in the cylinder.

In any mod the object is to get more power out of that combustion charge, so changes to the cam (valve lift duration, overlap, etc), cfrank shaft, pistons, even the rings can help gain some lost power from that fuel/air charge.

But that's my laymans point of view with some aviation maintenance background. There are others here that could go more in depth with the what, how, why.

Yo, Vendors.. wanna chime in?

[WhiteCrane]

It's a 2010 GT... Please don't kick me off the forum. I don't talk crap about Camaros. Love them in fact.

[Zabo]

Originally Posted by WhiteCrane

It's a 2010 GT... Please don't kick me off the forum. I don't talk crap about Camaros. Love them in fact.

It's the same concept regardless. And don't worry about owning a '10 GT here. You'd probably get more s**t from other stang owners for even hanging around here.. Chally owners would probably shoot all of us on site *rimshot*

But with your Modular V8 being a DOHC (dual overhead cam) I think a cam change is less involved as opposed to our pushrod setups. Concept is the same, however. So in the end the cheap mod of doing a CAI is already done stock, but a tune and probably a cam change could help with some power gains. That Mod V8 is pretty tapped out as is right now.

Most guys just go with a supercharger or a turbocharger setup to force more air into the engine, thus making that air charge more powerful.

[DGthe3]

I can tell you how it all works but I can't really tell you what to expect as far as gains on your car. Might have better luck with that on a Mustang specific forum.

Originally Posted by Zabo

But with your Modular V8 being a DOHC (dual overhead cam) I think a cam change is less involved as opposed to our pushrod setups. Concept is the same, however. So in the end the cheap mod of doing a CAI is already done stock, but a tune and probably a cam change could help with some power gains. That Mod V8 is pretty tapped out as is right now.

Most guys just go with a supercharger or a turbocharger setup to force more air into the engine, thus making that air charge more powerful.

2010 GT's are SOHC. Switched to DOHC for the 2011's with the 5.0L.

Anyway, cam swaps are simpler on pushrod engines. Setting the timing on a OHC setup can be a royal pain, particularly if you've got 4 of them.

[WhiteCrane]

Just out of curiosity why wont any manufacturer commit to how much hp you gain on a stock mustang?

i Thought the whole point of cat back exhaust systems and headers, and a manifold was horsepower. I guess not. Sounds like its all for noise.

[drummer5679]

Originally Posted by WhiteCrane

Just out of curiosity why wont any manufacturer commit to how much hp you gain on a stock mustang?

i Thought the whole point of cat back exhaust systems and headers, and a manifold was horsepower. I guess not. Sounds like its all for noise.

you do get gains but depending on what brand, size, etc.. of headers and exhaust system you buy it can vary. You can get significant horsepower gains from replacing your exhaust system but expecting people to be able to tell you exactly what results you will get on your specific car is naive. Most people can tell you a general area of what you can expect with certain mods on a Camaro and not a mustang because this is a Camaro forum.

[WhiteCrane]

Drummer, I agree with you.

I just think its odd that MagnaFlow wants to sell me an exhaust, and Magnaflow wont comment on how much horsepower I can get. I don't expect a Camaro forum to know.

I guess I have to go to a mustang forum... my god, mustang owners are so damn annoying. I was hoping I could stay here. You're all so much more pleasant.

[DGthe3]

Originally Posted by WhiteCrane

Just out of curiosity why wont any manufacturer commit to how much hp you gain on a stock mustang?

i Thought the whole point of cat back exhaust systems and headers, and a manifold was horsepower. I guess not. Sounds like its all for noise.

Some headers do relatively little, but are emissions legal in every state. Others can provide a decent gain, but aren't always emissions legal. A cat-back system can free up a few horse power, but most of the time people do it for the sound. So its entirely possible that one combination of headers + catback = +5 hp, while another combo could be +25

[The Stig]

Long tube headers are where you will see the most gains. Especially if you get a tune. High flow cats will add rwhp as well. Catback exhaust is a very small amount of hp, and axlebacks are purely for sound. Certain CAIs will also give you decent sized hp gains. Injen advertises 17 hp from there CAI.

[Shadowsong]

A lot of the reason no one really tells you what the gains would be on a cat-back (or any other mods) is because no one really knows, all cars are different, and respond differently to mods. On top of that, some people read their hp at the crank, and some prefer to know what they are putting down at the rear wheels. They can (and usually do) give a ballpark number, sometimes it is inflated a bit, but it is a ballpark nonetheless.

Given that you have a 2010 GT, I would say your best bang for the buck would be a CAI/Tune combo from American Muscle, and a catback exhaust, if you have some extra cash, you can go for long tube headers as well. You are worried about the tune voiding your warranty, don't. The American muscle tune comes on a hand held tuner, and it takes about 5 minutes to flash your car back to the stock tune, and the dealer will never know (chances are they wouldn't know if you DIDN'T put the stock tune back on before you went in for work, unless they needed to check the ECU for something). Tunes REALLY wake those 4.6's up. Some have gained as much as 20-30 WHP.

The reason I suggested the American Muscle tune though, is because they are a top notch company, when you purchase a tune from them, you get free retunes for LIFE. So, you order the tune and all you have on your car is a CAI, they write the tunes for a car with a CAI. Say a few months later, you get Longtube headers, Highflow cats, and Magnaflow exhaust, you shoot them and email listing your new mods, and they will email you updated tunes, that incorporate the new mods, they even tune for forced induction! As far as I know, no one else offers this kind of service. Also, the SCT tuner they use, can store 3 tunes, so you get 3 different tunes. You chose the octane rating, and street, performance, or race, for each tune.

I don't work for American Muscle, they just do great things for the Mustang community, I'm sure most Mustang guys would agree.

[WhiteCrane]

Thanks for educating me!