what makes shorty headers not that great ? is it the short tubes or the short collector ?

 

shorter primaries and also alot of them use the stock ypipe...which is pretty restrictive

 

Some also only have 1 5/8'' primaries. For many a good mid lenght header is the way to go.

 

With the LT1 short headers do make a significant difference. Here's a picture of the exhaust manifold borrowed from another post:

They look like something from a tractor. The LS1 exhaust casting in contrast is much less restrictive, hence there's not a lot of power to be had by switching to short headers there.

 

What kind of gains can be seen from a set of mid lengths?

 

alot of it just has to do with the diameter of the primary, if u think about going from a 1-5/8" to 1-3/4 u actually gain a inch in exhaust diameter..... well kinda. i believe the mids are 1-3/4" and are suprisingly equal to the long tubes, dont take my word for it never tried it out.

 

According to one leading manufacturer their "mid" length headers for the LT1 engine increase horsepower by 7 to 16 (8 - 12 LS1) and middle range torque is improved. Not a lot of new hp but any performance modifications will take advantage of the efficiency of the free flowing exhaust. Headers by themselves make a modest performance contribution. It is in conjunction with other power adders where they're supposed to benefit the most. H/C, n2o and forced induction are crippled with the factory exhaust.

 

The increase is 1/8" in diameter.

 

If you don't want to go long tubes, the Mac headers are definitely the way to go. They make great power, easy to bolt on and good ground clearance.

We have them on special too!

 

That's what I was wondering. If you run mids with the included y-pipe and a cat-back, the gains should be fairly decent shouldn't they?
Fast_Toys, do you have the Mac's in a ceramic coating?

 

I agree, Mac's have an awesome reputation for fit, quality, and value. They also have about the best plug access of any header. People have reported 20rwhp gains with them. They can't hold you back to much, if you check out www.advancedinduction.com they have a guy making over 400rwhp with them.

 

We don't have them in stock with Ceramic coating. You can always send them off to Jet Hot if you absolutely want them coated. Most people don't bother.

We have several customers making 400 RWHP with Macs.

 

Plug access really sucks with my SLP's. The stainless is nice though.

 

Isent you a email a week ago but could not reach you. I would definitely go w/the cermamic coated ones as to go thru all that work to install and have them look s******
soon after doesn,t cut it . Even the old 10 yrs old Blackjack Alum 5000 on my 79z still look decent.

 

Uncoated headers raise underhood temps and also cause premature spark plug wire failure. Definitely get your headers ceramic coated!