What do longtube headers do for sound? Does it make the sound alot louder?

 

It definitely makes it louder. The term "a lot" is all in the perspective of the listener I guess.

 

Alot depends on weather you get an X or H pipe, cats or no cats. All contribute to your sound.

 

I got the x pipe and cats (SLP). The sound is for me, the *&(*&(. it is kick butt. I have read that you lose very little HP for going with cats. I would have preferred the H pipe, but since Shelby is going with it, it must be a better deal.

 

I have Kooks LT's and their high flow catted Xpipe with Mac axlebacks and the sound is excellent IMHO. Not obnoxius when just cruising but you can make bicycle riders crash when you gag it! hehe

 

sound is all about the mufflers you use. With stock mufflers it will be a little louder.

 

Can someone explain the difference between long tube and short headers? What is the performance advantage of one vs the other?

 

short tube headers work better at high rpm's where as long tube headers work better in the lower rpm range.

 

Ok, out on a limb here, but LT's are for the most part "balanced" or "Tuned", maybe not the right term. In order to pull or effectively scavange the exhaust out of the engine, the individual ports must be the same distance from the exhaust port to the collector. This causes a pulse or vaccum as one tube empties into the collector. LT's allow for this and us old dudes remember that LT headers are really the only true header. Some shorties try to do this...JBA is one that comes to mind. Most (like FRPP) only slightly modify the tube path and distance.

Shorties use the existing exhaust piping, LT's make you change out the cat area, because they are longer over all.

Shorties show only a slight 1 - 3 hp increase. Most LT's increase it from 20 to 25 hp. Not sure about the sound of Shorties? never heard a set on a car before.

 

never heard that before...


Longtube headers will tend to flow better than any shorty header just because of their size/dimensions...Read the above post for more info ^

If you look at the size of the header most companies will sell 1 3/4" and a 1 5/8" width tubing. The 1 5/8, which is slightly smaller, will improve power down low in your RPM range, while sacraficing a little power up top...While the 1 3/4" piping will improve power higher up in the RPM range because it is bigger, therefore flowing more air.

 

http://www.carcraft.com/techarticles...st/index1.html

The Long and the Short of It

This is an interesting test of header length. Test 5 compares standard-length 15/8-inch headers to Test 6 with the same diameter but shorter-length intermediate headers. By looking at the Difference column, you can see that the shorter headers sacrificed torque below 3,600 rpm but made up for that by making as much as 23 more horsepower at the top. The average torque made by both engines is within 1 lb-ft, which is negligible. Basically, the shorter headers moved the torque higher up the rpm curve. If you plugged the intermediate-length header curve into a light car like an early Mustang or early Chevy II, for example, where you could not use a large tire, then the shorter headers might make traction a little easier to achieve. But you'd want to use the long-tube headers in a big, heavy vehicle or a truck where the stronger torque curve would help acceleration. Test 5: A mild 355ci small-block with Hedman 1 5/8-inch, 34-inch long-tube headers with a 2 ½-inch exhaust system and a pair of Flowmaster mufflers.
Test 6: Same as above except with a set of Hedman 1 5/8-inch intermediate-length headers.

 

I have JBA longtubes and they seem to be very high quality and with the other mods I have on the car it really moves right now. However the headers definitly have a peculiar sound. They sound like there is a small exhaust leak at the headers, but my install shop assures me that that's just the sound of the thinwall stainless headers. It's a fairly subtle inoffensive sound and if it really isn't a leak I don't have a problem with it. So what's the story? Is my shop BSing me or do headers tend to have a "tinking" sound upon acceleration?

 

YOU HAVE THAT TOTALY BACKWARDS

 

You do get header noise which is sort of like "tinking". You can hear the cylinders exhaust individually at the header which you did not with the iron manifolds.

 

So then shorties will give you the power at the lower end of the RPM band?

 

Shorties don't really give you power at all... I don't think 5rwhp is worth the cost.

 

check out the link/article.

 

How did the install go? Did you attempt it yourself or have a shop do it? I want to do LTs and I want to see if I need to budget some extra $ for installation or do it myself on jackstands in the garage.