I was flipping through car craft and came across a header comparison. 1 5/8 longtubes made 327 Hp @ 4,600 and 439 Tq @ 3,000 And 1-5/8 midlenghts made 338 Hp @ 4,600 and 433 Tq @ 3,400 And after 3,400 the midlenghts OUTPROFORMED the longtubes to redline

 

Well its good thing i have 1 3/4 long tubes

 

what brand were they? Maybe it was a good mid and a crappy longtube? But in most cases i think the LT will always out perform the mid.

 

The thought that longtubes always outperform mid lengths is another one of those, "my buddy did it" things I run across on here quite a bit. Too many people get tied up in the "buzz word" thing. Many people think you've got to have LT's to run fast.
These aren't new tests. It's a proven fact that mid length headers (of the same tube diameter) will usually make more top end HP than longtubes. Longtubes will, however, usually make more low end torque.


Frank

 

One would only loose hp and tq if you put 1 3/4 long tubes on a bone stock motor. I mean loose power compared to mid tubes. One would see better hp and tq specialy tq with a 1 3/4 mid tubes on a stock motor. Plus who makes the headers and how good they were made all makes a differnce as well.

 

Injuneer tested a set of AS&M mid lengths that had been modified to have 3" collectors (I think that was all) against a set of Hooker (?) long tubes on a race only motor. I don't think they even started recording on the dyno until over 5000 rpm, but the mid lengths outperformed the long tubes. Not exactly a great test for what to put on you street car but this is the most reliable comparison i've seen.

 

They were Hedman headers. From what I read unless your car is producing 420 hp or more 1-3/4 size headers hurt you more than 1-5/8.

 

well i dont make near 400hp and my lt's helped out a lot my car is a lot faster

 

...but one of my buddies had LT's and said midlengths were crap...

 

Your on crack buddy Good LT's (hooker, jethot) will outperform mids any day of they week.

 

My buddies SS with Mid-lengths and Borla is a slug compared to my LT's and Loudmouth.

 

In his building horsepower book Vizard says the longtubes usually make more low end torque but the mid lengths give more top end HP. He tested a couple systems side by side and on similar motors the mid lengths gained about 10 hp over the lt's, at the expense of a lot of bottom end torque.

 

I would think it would be the opposite. LT's would give it more room to breath up top, better flow.

 

Again...Are we basing this on FACT or OPINION? I've seen many dyno test that show mid lengths making more top end HP. I think this...This should be...Or "You would think" doesn't show on the dyno.

Anyone got any back to back dyno pulls, or quarter mile times between mid lengths and LT's?

I don't think my mid lengths are holding my car back too much. My full weight, stock 95,000 mile bottom end, 93 Z went 12.0 last Saturday...In 80 % humidity.

Frank

 

Pick up the latest Car Craft its a fact.