Shorty Headers - Questions about Which Ones and Installation

[AndyGJ]

Well, here I go again...looking to do another weekend mod project.

 

I've updated the Axle Backs to the KR Mufflers, and now I'm looking at adding Shorty Headers. I noticed that the SGT just has the stock Mustang GT exhaust manifolds on it, and that SAI did not update these in the process. That being said, here are my questions:

 

1) Which ones would you suggest? I noticed that FRPP has a set for around $350. Are these any good?

Anyone using these on their SGT?

 

2) What kind of performance gain would I get from the shorty headers?

 

3) Any side effects that I need to know about as a result of adding these?

 

4) Are these simple bolt on installations from both the block and the pipes side? Any special tools I'll need to have on hand? Any heads up about the installation process I should know about? Is this process done primarily from below the car or will I also need to access some items from above as well?

 

As you can tell, I've never ventured into these waters, but would love to do this one myself. Any help or comments would be greatly appreciated!!

 

Thanks,

Andy.

[07SGT]

http://www.jbaheaders.com/feature_pages/05mustangnew.asp

 

http://www.jegs.com/InstallationInstructions/300/397/397-M-9430-S197.pdf

 

JBA's are equal length and I believe they are still smog compliant.

[ARMORINE]

5-10 hp. im not a fan of shorties as they dont do much. they look nice and have alittle bit of a gain theyr just not that great though. on the other hand theyr easy to install and theyr not very pricey.

[AndyGJ]

_{I looked at the long tube headers and the quote I got from a local shop for the headers and installation was way over my expectation at $3,100.}

_{I figured with the shorty headers that I may be able to do those myself, but not 100% sure - that why all the questions about it. I didn't get any pricing yet on what shorty headers would run as I initially thougth I could do these on my own.}

 

_QUESTION:

_{In the Installation Instructions above, it says that the motor mounts have to be loosened and the motor lowered to remove and install the shorty headers - is this correct and customary?}

_{If so, it may be more than I'm willing to tangle with on my own.}

 

_Thanks,

_Andy.

[07SGT]

http://www.allfordmustangs.com/forums/4-6l-tech/228222-shorty-headers-install-2001-mustang-gt.html

 

http://www.allfordmustangs.com/forums/2005-2010-mustang-gt-tech/158525-2007-mustang-gt-jba-header-install.html

[americaniron]

I've put long tubes in my car, and shorties in my Brothers Shelby GT, and the amount of work to do either is nearly the same. The cost of the parts is the main difference. It really isn't hard to do if you can find a lift to rent. I'd seriously recomend that you use a lift if possible. If you don't want to tackle the job yourself, then you shouldn't have to pay more than $300-400 for the job. I also found it easier to disconnect the steering rack as well as lifting the motor from the mounts for the job. Once you get started it really is easy. A set of swivel sockets made it easier for some of the bolts.

[ARMORINE]

_{I looked at the long tube headers and the quote I got from a local shop for the headers and installation was way over my expectation at $3,100.}

 

 

 

WTF!??!?!?! that shop must be selling something out the back and smoking it too! holy crap! that's ridiculous, long tube installs arnt too hard and can be done in the garage without a lift if your crafty.

 

to install BIG longtubes like mine you have to unbolt one of the motor mounts and lift the engine about a half inch to slide the headers into place. keep in mind this is only for large lt's the smaller ones can sometimes be slid into place without unbolting anything.

 

id find a different shop. that ones smoking something.

[07SGT]

another person on another site stated he paid a ford dealership 500.00 to install. The equal length headers may be wider than long tubes and require more room to work.

[08sgt1042]

I went with Ford racing shorty headers, got a local mechanic to install them for a reasonable $300 so all total $650.

[AndyGJ]

I went with Ford racing shorty headers, got a local mechanic to install them for a reasonable $300 so all total $650.

 

 

Now that is about the price I was originally thinking....how do you like the Ford Racing headers? Were you able to tell a difference in the power and any major difference in the exhaust sound?

 

I'm after the power gains and OK with how the KR mufflers sound now, so I'm not looking to go louder (that is one reason why to look at the shorty headers versus the long tubes - I've heard that the LTs are louder).

 

thanks,

Andy.

[young768]

Andy, you do remember that I have the FRPP headers installed? Give me a call or stop by so you can see how they fit and look.

 

Robert

[springer]

For a 10-15 hp increase the shortie headers would not be prudent at all. I would install long tube headers, but not unless I was also doing other mods that would benefit the engine. I'd be surprised whether you would even notice a difference in long tubes without other modifications too.

[TheKurgan]

I'm of the thought headers provide very minimal, if any gain, up to around 700HP. Getting rid of your cats will provide a 10-15HP gain up top though. My .02

[AndyGJ]

Do the headers work better in conjunction with things like the Hot Rod cams?

[08sgt1042]

little difference in HP gains by seat of the pants but did notice a difference in exhaust sound. I struggled with the LT vs Shorty $$ was what made my decision and I went with chrome for the show aspect, it comes down to $$$ and type of mods you will be doing I did chrome cam covers at the same time installed them myself.

[Dig-It]

Andy,

 

I put the FRPP shorties in my SGT for the looks (ceramic coating) and the sound (a little deeper) - not for power. I did the install myself and did not have to lift the motor to get them in.

 

As soon as I have the coin, I'll install Kook's longtubes in the Boss 302 for power and noise - lots of it!

 

Kevin

[07SGT]

Dit-It, which type/brand did you install?

[2010KonaBlueGT]

Do the headers work better in conjunction with things like the Hot Rod cams?

 

 

Everything changes when you go from Naturally Asperated (NA) to Super Charged (SC).

 

The theroy behind "Tuned Headers" is that one tube next to another pulls air out of the cylinder and into the collector via the scavenging effect. Without any question, Long Tube (LT, i.e. "Equal Length") headers make more power on a NA engine where as on a SC engine, you have PRESSURE from the SC pushing air out of the cylinder into each tube so there is in essense, NO scavenging effect with headers, LT or Shorty's.

 

I've seen claims of more than double HP numbers from LT's vs. Shorty's and I'm not buying it. In fact, the longer primary tube will create MORE resistence due to the longer length of the tube vs. the shorter tubes on a set of Shorty's. The key to getting power out of a SC engine is to reduce exhaust restriction as much as possible. A free flowing exhaust is the key (for the EXHAUST aspect of it). The same applies to the intake tract. You can not "over port" a set of heads used on a blown motor, unlike a NA engine where you can kill low end just by taking .010" too much off of the roof or floor of the port.

 

EDIT: Look at any Top Fuel or blown car running in NHRA. Top Alcohol Dragster or Funny Car/Coupe, Top Fuel Dragster or Funny Car/Coupe and what do you see for exhaust? Equal Length Headers? No. Tuned Headers? No. You see a set of SHORT Zoomies.

 

I personally went with the FRPP Shorty headers due to the ground clearence issues LT's create. I looked under a GT500 w/LT's on it and he had *maybe* 1 inch of clearence under the car. And I say, *MAYBE*. The owner told me he can't even go over a small speed bump in most parking lots, and his car wasn't lowered that much.

 

My shorty set along with my Roush off-road Extreame exhaust gives me all of the free flowing I can expect, WITH CAT's on the car. My next step will be a cat-less X tube.

 

And I still have my ground clearence, minus the amount that I lowered the car.

 

 

Phill

[Dig-It]

Dit-It, which type/brand did you install?

The FRPP ceramic coated.

 

Phill, good post - right on the money.

[andrewnagle1964]

Andy,

 

I put the FRPP shorties in my SGT for the looks (ceramic coating) and the sound (a little deeper) - not for power. I did the install myself and did not have to lift the motor to get them in.

 

As soon as I have the coin, I'll install Kook's longtubes in the Boss 302 for power and noise - lots of it!

 

Kevin

 

This is the route I went with put on ceramic coated FRPP shorties and now have ARH 1 3/4 LT's

 

Andrew

[07SGT]

Kona, I have to ask; how does a SC push the exhaust out. The SC only provides boost to the intake stroke of the 4 cycle engine. The intake valve is then closed after ignition and the exhaust valve opens on the exhaust stroke. So it would, in my humble opinion, still be only the same exhaust stroke that is pushing the exhaust out of the cylinder. I do not think the SC would have any effect on the exhaust. Am I wrong?

[AndyGJ]

The FRPP ceramic coated.

 

Phill, good post - right on the money.

 

 

Can you still get the FRPP ceramic coated shorties? I looked on-line as those were one of my first choices, but it showed discontinued product I think. I'll check again, but that would be great to have.

 

Kevin - did you notice any gains in power? Why do you say tons of power gain on the Boss 302? I understand the sound, but didn't know if it affected the 5.0 engine differently from our 3v 4.6 motors.

 

Thanks,

Andy.

[Dig-It]

Interesting ... I don't see them on the Ford Racing website anymore.

 

I was referring to how much louder the longtubes are - especially with the off-road pipe I'm looking to get.

[AndyGJ]

Interesting ... I don't see them on the Ford Racing website anymore.

 

I was referring to how much louder the longtubes are - especially with the off-road pipe I'm looking to get.

 

 

Kevin - how much louder did the exhaust get when you added the FRPP shorty headers to your SGT? I just added the KR mufflers (love them!) to mine, so I have the right amount of volume that I like on the loud side of things. An earlier comment on the headers said that it didn't get louder, just smoother sounding on the shorty headers is what they noticed.

 

Any thing you recall about the change in sound?

 

Thanks,

Andy.

[AndyGJ]

Everything changes when you go from Naturally Asperated (NA) to Super Charged (SC).

 

The theroy behind "Tuned Headers" is that one tube next to another pulls air out of the cylinder and into the collector via the scavenging effect. Without any question, Long Tube (LT, i.e. "Equal Length") headers make more power on a NA engine where as on a SC engine, you have PRESSURE from the SC pushing air out of the cylinder into each tube so there is in essense, NO scavenging effect with headers, LT or Shorty's.

 

I've seen claims of more than double HP numbers from LT's vs. Shorty's and I'm not buying it. In fact, the longer primary tube will create MORE resistence due to the longer length of the tube vs. the shorter tubes on a set of Shorty's. The key to getting power out of a SC engine is to reduce exhaust restriction as much as possible. A free flowing exhaust is the key (for the EXHAUST aspect of it). The same applies to the intake tract. You can not "over port" a set of heads used on a blown motor, unlike a NA engine where you can kill low end just by taking .010" too much off of the roof or floor of the port.

 

EDIT: Look at any Top Fuel or blown car running in NHRA. Top Alcohol Dragster or Funny Car/Coupe, Top Fuel Dragster or Funny Car/Coupe and what do you see for exhaust? Equal Length Headers? No. Tuned Headers? No. You see a set of SHORT Zoomies.

 

I personally went with the FRPP Shorty headers due to the ground clearence issues LT's create. I looked under a GT500 w/LT's on it and he had *maybe* 1 inch of clearence under the car. And I say, *MAYBE*. The owner told me he can't even go over a small speed bump in most parking lots, and his car wasn't lowered that much.

 

My shorty set along with my Roush off-road Extreame exhaust gives me all of the free flowing I can expect, WITH CAT's on the car. My next step will be a cat-less X tube.

 

And I still have my ground clearence, minus the amount that I lowered the car.

 

 

Phill

 

 

Great post Phil....Thanks for the info.

I understand a lot more about how these work now.

 

Thanks,

Andy.

[2010KonaBlueGT]

Kona, I have to ask; how does a SC push the exhaust out. The SC only provides boost to the intake stroke of the 4 cycle engine. The intake valve is then closed after ignition and the exhaust valve opens on the exhaust stroke. So it would, in my humble opinion, still be only the same exhaust stroke that is pushing the exhaust out of the cylinder. I do not think the SC would have any effect on the exhaust. Am I wrong?

 

 

The supercharger induces boost into the cylinder. Boost is described as any pressure above atmospheric pressure. But I'm getting ahead of myself.

 

I'll use some numbers that aren't necessarily real life numbers, just for the sake of discussion and to make things easier to understand.

 

Let's say we have a 400 cubic inch (ci) V-8 engine. Each cylinder would displace 50ci.

 

Let's say that this engine has 100% volumetric efficency (VE).

 

 

A Naturally Asperated (NA) engine:

 

For each Intake Stroke of the engine, each cylinder fills with 50ci of air/fuel. The atmospheric pressure (at sea level) is 14.7 psi. The atmospheric pressure pushes 50ci of air into the cylinder and mixes a very slight amount of fuel with it. The intake valve closes, the piston starts its upward movement compressing the A/F mixture (Compression Stroke), the spark ignites the fuel and Oxygen, the heat generated by the ignition heats up the remaining Nitrogen in the cylinder and the Nitrogen expands pushing the piston down in the bore creating the Power Stroke.

 

The exhaust valve opens and the piston starts moving up in the bore (Exhaust Stroke) pushing the (mostly) Nitrogen out of the bore via the exhaust port...AT ATMOSPHERIC PRESSURE.

 

(In real life: The exhaust is being pushed out by the piston and the tuned header is actually pulling the cylinder down with a *slight* vacuum (Vacuum = any pressure *below* atmospheric pressure) due to the scavenging effect of a tuned header, which in the real world helps the engine achieve *greater* than 100% VE by pulling in the next intake charge with a cylinder that is already below atmospheric. But again, for discussions sake we're working with 100% VE.)

 

 

A Super Charged (SC) Engine:

 

Now we add a supercharger to the engine. We'll run it at 14.7 psi of boost (i.e 1 BAR). By doubling the pressure (from 0 psi to ~15 psi) we are now forcing 100ci of air/fuel into ea. 50ci cylinder (i.e. 200% VE!). We have produced a *pressure* inside of the cylinder, above atmospheric pressure, not just at atmospheric pressure such as in the NA engine. We have essentially "stuffed 10 pounds of shit into a 5 pound bag". The intake valve closes, the piston compresses the A/F mixture and the spark ignites the fuel, burns most of the oxygen in the mixture, the burning oxygen heats up the Nitrogen, the Nitrogen expands pushing the piston down into the bore for the Power Stroke. But now when the exhaust valve opens, the cylinder is already under 14.7 psi of pressure and the pressurized cylinder PUSHES the Nitrogen out of the cylinder before the piston even starts to move up. Start moving the piston up and you have now pushed 100ci of Nitrogen out of a 50ci cylinder. UNDER PRESSURE.

 

Start with no pressure and all that moves the cylinder contents out is the piston moving upwards in the bore. Start with double the pressure (boost) and you have the pressure AND the piston moving up in the bore pushing the contents out.

 

I probably just complicated the snot out of a super simple explaination. I tend to do that in my attempt to "simplify" things but I'm hoping I got the point across.

 

FORCING air out is not the same as DRAWING air out. You can only pull so much vacuum but you can push any amount out that you can pressurize. And force air IN, you'll force air OUT (i.e. Super Charger).

 

 

Phill

[jsarkis]

Dam Phill, I wanted LTs before I read your posts

 

On the positive side I must thank you because now I'll save some $$$ and just get a mid pipe with high flow cats.

[MyBlueHeaven]

Dam Phill, I wanted LTs before I read your posts

 

On the positive side I must thank you because now I'll save some $$$ and just get a mid pipe with high flow cats.

 

 

I still do but I feel like there should be a test and maybe some credits for that lesson.

 

Awsome explanation Phil, thanks.

[07SGT]

Phil, again, I could be wrong but.... the sc does not push the mixture out of the cylinder. I am aware of the four cycle engine and the functions of each stroke. But the SC does not push anything out as the intake valve is closed during the exhaust stroke so the SC has no effect on the contents of the cylinder at that time. The SC only has an effect through the intake port/cylinder and once the intake valve is closed the SC has no effect on that cylinder until the next intake stroke of the piston. The SC does not push anything out of the cylinder. The only pushing out of the cylinder is accomplished by the upward stroke of the piston on the exhaust stroke. The SC is not involved in that function either. The unburnt mixture is pushed out by the upward travel of the piston and the exhaust flow is compounded by the scavenging (sucking) of the unburnt fuel mixture due to the tuned headers. The pulses of each exhaust exit create the vacuum to suck or scavenge the exhaust more completely from the cylinder and the exhaust manifold. The exhaust stroke is not under 14.7 psi (barometric) as there has been a more complete burning of the air/fuel mixture and that entire energy is consumed by the power stroke. As the piston nears bottom dead center the exhaust valve opens so there is no pressure on the cylinder or the piston and it is the piston that effectively pushes the unburnt mixture out of the open exhaust valve. The SC has no effect on the exhaust stroke or the scavenging effect. IMO.

[Frank S]

Nice exposition, Phill. If I could have understood it I might have said, "Uh-huh, just what I thought". As it is, I just will mention that valve overlap has different effects on 'charged engines than on normally aspirated ones.

 

As to the shorty headers: they are more like jewelry than jock-straps. For those who value a lumpy idle, the noise of tubular headers is a real plus: that "tink, tink, tink" usually damped out by cast iron is sweet to the trained ear, and you don't have to open the hood to verify it.