Have I Peaked?

[MrBenchMark]

First of all I want to thank each and every individual who has helped me along the way here in this forum. It is much appreciated!

The title to this post relates to the question I have in wondering if I've peaked as far as modifying my current vehicle. I want an overall efficient vehicle in terms of HP and MPG and don't want to do anything to the vehicle that will decrease anything from how it came out bone stock. The only thing I haven't done to my car yet, but am waiting on delvery, is to install a Diablo Catch Can and a 180 degree Jet T-Stat.

Am I at the point where I've gone about as far as I can go and to leave it alone and maintain it, OR are there any other modifications I may want to consider that will make it an even more effecient than it is now?

Thank you for everything!

[Mike_Levy]

Heads, cam, headers. Anything that improves efficiency will increase hp and mpg.

[MrBenchMark]

Heads, cam, headers. Anything that improves efficiency will increase hp and mpg.

Mike, I appreciate your reply.

In regard to headers, I have considered the purchase however the gentleman who installed my magnaflo mufflers actuallly discouraged me from installing headers. The reason he gave was, "Unless you're racing, it's not worth it. The gaskets are infamous for leaking and you'll find yourself every year or so replacing the gaskets." So with that being stated, I decided against it.

Your thoughts?

[Quick]

All depends on how the headers are installed... Headers seem to be prone to have the nuts come loose. You can invest in studs/nuts with a positive locking mechanism. It's a matter of cost. The best power and mpg modification would be forced induction... be prepared to pay in the vicinity of 10K.

I don't understand the MPG requirement? You want to increase HP without decreasing MPG. The question is why? There is a 3rd factor in there. HP, MPG and cost. You can increase HP and MPG with a predator. Let's say you gain some number of hp and 2 mpg. How long does it take to recoup the cost of the predator with the increased MPG? If it's a matter of how much each hp cost you then the gas is the least significant factor.

[Mike_Levy]

I've had headers on 4 cars, and have never had a gasket leak. I always use Stage 8 locking bolts. And theres a definite power gain from them, always. That especially stands true on your 5.7, which has crummy exhaust manifolds.

Pick up a set of long tubes and tell the naysayers to F-off.

[MrBenchMark]

I've had headers on 4 cars, and have never had a gasket leak. I always use Stage 8 locking bolts. And theres a definite power gain from them, always. That especially stands true on your 5.7, which has crummy exhaust manifolds.

Pick up a set of long tubes and tell the naysayers to F-off.

Mike, specifically what brand of headers do you recommend for what I have. Exhauast system.....et al

[MrBenchMark]

All depends on how the headers are installed... Headers seem to be prone to have the nuts come loose. You can invest in studs/nuts with a positive locking mechanism. It's a matter of cost. The best power and mpg modification would be forced induction... be prepared to pay in the vicinity of 10K.

I don't understand the MPG requirement? You want to increase HP without decreasing MPG. The question is why? There is a 3rd factor in there. HP, MPG and cost. You can increase HP and MPG with a predator. Let's say you gain some number of hp and 2 mpg. How long does it take to recoup the cost of the predator with the increased MPG? If it's a matter of how much each hp cost you then the gas is the least significant factor.

In re wording my post, I am under the impression I gained HP and MPG with installing a CAI, having magnaflo mufflers installed, and having a DiabloSport Predator canned 91 octane w/ CAI installed. It seems to have worked and I am happy with the extra HP I am getting now along with the MPG.

Now, I understand there are things I can do to gain MORE HP, but if all I am doing is adding more HP on top of what I have now, but at the same time potentially getting less MPG than what my car would get with no mods, it's not worth it to me personally. There are mods that advertise increased MPG and HP but I would think at some point your MPG would peak and plateau, and even though you might gain more HP by adding various mods, your MPG might start to decline instead of increase. Whenever that should happen, that’s where I will stop with the mechanical modifications, and begin concentrating on exterior/interior modifications.

Do I make sense? Your thoughts? Anyone?

Oh by the way, thanks for the info about the headers!

[johan]

There are some good quality headers out there, i am partial for the Kooks (have them on my own rides) and never had any leak issues.
You will love the way the Kooks sound a 5.7L, they do pick up decent power due to the poor design of the stock ones.
Head and cam usually do not affect MPG if the vehicle is tuned properly for it.
Another thing you might want to look for is an uncerdrive pulley, worth close to 10rwhp.

[Mike_Levy]

Kooks has an issue with throwing the CEL. I'm actually not sure what won't throw a code on 5.7 cars.

[MrBenchMark]

There are some good quality headers out there, i am partial for the Kooks (have them on my own rides) and never had any leak issues.
You will love the way the Kooks sound a 5.7L, they do pick up decent power due to the poor design of the stock ones.
Head and cam usually do not affect MPG if the vehicle is tuned properly for it.
Another thing you might want to look for is an uncerdrive pulley, worth close to 10rwhp.

In the last sentence, is that a typo (RE: uncerdrive)? Should it be, underdrive? Hell, I don't know....lol!

REVISION!!!

Ok it was a typo and I've been reading about what a underdrive pulley actually is and have found out quite a bit. Only thing I am wondering now is if there is a specific brand that is the best among the rest, or are the all pretty much the same?

[MrBenchMark]

Kooks has an issue with throwing the CEL. I'm actually not sure what won't throw a code on 5.7 cars.

Johan, do you any comments to make regarding the comment above?

[mikel]

Kooks has an issue with throwing the CEL. I'm actually not sure what won't throw a code on 5.7 cars.

Johan, do you any comments to make regarding the comment above?

Johans dont throw any codes....

[Mike_Levy]

Kooks has an issue with throwing the CEL. I'm actually not sure what won't throw a code on 5.7 cars.

Johan, do you any comments to make regarding the comment above?

Johans dont throw any codes....

Does he have the rear O2s turned off?

[MrBenchMark]

Johan, do you any comments to make regarding the comment above?

Johans dont throw any codes....

Does he have the rear O2s turned off?

Ok...I am getting really confused here. Mike who are you referring to and Mikel, please clarify what you meant...lol!

[mikel]

Yes, Johan has the rear O2s disabled and it throws no codes.

It will NOT pass a plug in emissions test like that.