My plan is to install a set of long tube headers on my 1994 LT1 Corvette with new high flow cats and keeping what I can of the Power Effects exhaust that is presently on the Vette. The Vette is used mainly for drag racing. I have port matched stock heads & intake, 1.65 roller rockers and the GM "hot cam". The bottom end is completely stock. I run a "beefed-up" automatic with a Pro Torque 2800 stall converter and a Dana 44 rear end with a 3.34 gear. I also have an SLP air intake system on the Vette.
The header I was thinking about buying was the Smooth Flow long tubes from Melrose. I saw some photos on the Forum and really liked the way these headers fit. A buddy of mine has a Melrose set on his '93 Vette but his Vette is dyno tested at 605 RWHP (7800 RPM) while mine has been dyno tested at 278 RWHP. Also I have learned the Melrose headers have 1.75" Primary Tubes which seem very large to me for a motor like mine that never sees more RPM's than 6200. I seem to remember that primary tubes larger than 1 5/8" can rob an engine of low end torque and really aren't effective until reaching 7,000+ RPM's. Is my memory correct? Should I look for a set of headers with smaller primary tubes or am I worring about something that is really a none issue?
In its current set-up and the cool October air the Vette has run 12.65 @ 111 MPH but the summer heat can slow it down by 2/3 tenths. I'm hoping the headers will allow me to pick-up 20 to 30 RWHP and help me into the 12.5's. Any information that can be offered concering a headers primary tube sizing will be appreciated. It seems every time I have my mind made-up to buy something for my Corvette a new factor is introduced and I've put off buying a set of headers long enough. Thanks for the advice.

 

I'm running EM 1 3/4 long tubes, and picked up torque throughout the entire rpm range.

 

You may want to look at the Stainless Works headers. They are the only LTx specific header being built with 1 5/8" primary tubes.

 

www.Tpis.com they are great headers, easy to install ( took me and silver86 about 30 minutes to put the new ones on, no joke.) changing spark plugs with them is really easy and they are made well. Powder coated and all. I suggest those, they are worth the money.
I have hookers on mine, if I was to do it again id get the tpis. The hookers arent bad though a little bit cheaper and prob flow the same.

 

TPiS on mine, great fit, and quality.

 

100% -- Here is my old installation thread for SW headers... http://forums.corvetteforum.com/show...+works+install .

 

You are correct.

To be fully effective, headers must match your particular engine.
Cam (with all its variables), rear gears, car weight, tire size, even driver preference all have an affect on the header's primary size, primary type, primary length, collector diameter, collector length, collector type, etc.

There is no best header for everyone, or, for that matter, probably not for any two cars!!

For a stock-engine, street-driven car, stay with the smallest primary and collector size you can find, with the longest primary length available. (Tri-Y's [4-2-1] are also worth considering.)
These headers will hurt you the least.

Good luck.

Larry
code5coupe

 

I agree with the 1-5/8" if you do headers. PM sent

 

30 minutes NO FOCKING WAY Myron him self with 2 of his best hands couldn't do them in even a hour

 

See my post on this here:

http://forums.corvetteforum.com/show...4&postcount=16

 

I went with a set of Melrose with no air,no egr, nad no cats went withthe x-tube. No problems hooking them up fit and finish were great, did have too do some minor modification to the x-brace under the car but well worth the effort. wro87