how much power out of lt over shorties

I currently have mac shorties, but a very well respected mustang guy i know told me that he gained about 15hp from long tubes on his bolt on 5.0 as opposed to 3hp from shorties, is this common, if so im thinking about switching.
 
FlyBy763 said:
Probably about right....I think the thing with long tubes over shorties is more the "area under the curve" that it gives you rather than peak power. Mine gave me about 2 tenths on an otherwise stock motor.

I agree :nice:

LT's will produce a noticable amount of low & mid range torque over shortys.

Peak hp difference won't be as great as the tq difference from my findings.

Grady
 
melo yelo said:
Long tubes over shorties, **** the smog nazis and tree huggers. Its all about hp and a nice broad and flat torque curve.

Would you believe I've passed the Texas State annual emissions dyno roller thingy instection with flying colors for the past three years. :shrug:

The tech even went as far as to show me my car burned cleaner than most others he had tested. :rlaugh:

Grady
 
Ya, I believe you did pass the inspection. I asked my smog tester dude about long tubes headers and he said "As long as you have two cats in the right place and the smog pump and EGR equipment is in place and functioning I can't fail you on the visual inspection".
Joe
 
This is from a post on corral

Before Exhaust:
DynoRunApril.webp


After Exhaust:
DynoRun11July.webp
 

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i was wondering the same thing grady, what brand of exhaust, what's the full setup, i'm also debating LT's or Shorty's. Shortys seem more practical as they are matching with stock so i can upgrade my exhaust system more 1 peice at a time, long tubes look pretty hard to get in there, and i'd have to do all of my exhaust @ once, lt/midpipe wise. I'll be making my mind up soon!
 
That first dyno curve looks like a failed run. The torque has a flat spot early on, and the run ended far too soon.

BTW, I would think it would be fairly impractical for someone to run a comparison dyno comparing shorties and LT given the work in installing LT headers. Unless you had the motor out and were running on an engine dyno. Maybe a before and after when installing LT, I guess. Anyway, hopefully that's what those graphs are showing. Please fill in the details on the runs, if available.
 
If long tubes help add torque then it only makes sense that they wouldn't make too much a difference up top as that is where the torque and horsepower curve cross.

Also does anyone have an explanation for the torque gains besides "they just do" or "it flows better"
 
I don't think anything is wrong with the first pull.

To me, it looks like the tech started capturing data a bit before he had the pedal to the metal.

I've seen curves that look like that from the start of the pull on more than one occasion before.

Grady
 
The way I understand it, headders are like anything else, it's a matter of what you are trying to do with your engine, the pipes have to match the rest of the combo. Generally speaking shorter wider pipes produce more HP, while longer narrower pipes produce more torque, so,if you're building a torque monster go with the long, if you're going for a top end screamer go with the shorts, and if you want the best of both worlds build the torquer and give it a 150 shot of go juice to help it at the top! Yeah baby!
 
SWYZ721 said:
Also does anyone have an explanation for the torque gains besides "they just do" or "it flows better"

The word is Scavenging.

Shortys are not long enough for the above to take place and they have no collector so to speak like LT's.

Simple and very crudely explained :(

With LT's, you got each tube ending in the collector. The different lengths of each pipe are fashioned in such a way that you get the benefit of this Scavenging effect. You got the different exhaust pulse waves from each cylinder ending up in the collector and this also aids in this Scavenging effect.

Put all that together (and most likely more that I don't know about here :rlaugh:) and the exhaust gasses literally get sucked out of the header by the other cylinder's pulses.

Extremely basic I know
but
kinda sorta how it works

Grady
 
95GTV8 said:
i was wondering the same thing grady, what brand of exhaust, what's the full setup, i'm also debating LT's or Shorty's. Shortys seem more practical as they are matching with stock so i can upgrade my exhaust system more 1 peice at a time, long tubes look pretty hard to get in there, and i'd have to do all of my exhaust @ once, lt/midpipe wise. I'll be making my mind up soon!

I'll give you a little challenge here. :D

Compare the dyno pulls of several street combos which have impressive torque curves. We are talking about one that is broad from low rpms and holds flat to mid rpm or above.

Then look at some pulls that have torque curves that are shaped similar to the hp curve.

See what kind of headers seem to be used in each of the two groups we have talked about. :shrug:

Grady
 
final5-0 said:
igotyofire

Have you got any more details other than .............

before & after exhaust :shrug:

Grady
Corral Thread http://www.corral.net/forums/showthread.php?p=5546281#post5546281

His user name is "Darren5.0L" on the corral forums and this is his mod list in his sig

1995 Mustang GTS
226.8 RWHP and 303.8 RWTQ NA
MAC Longtube Headers
MAC Prochamber
Ford Racing M51 Catback
ZEX WET Nitrous Kit w/Purge&Bottle Heater
March UD Pulleys
UPR Smog Delete
EGR Delete,
K+N
Cervini's Ram-Air
C&L Truflow Inlet Tube
Superchips Inc. Bluechip (it sucked, now gone.)
MSD Blaster
FRPP 9mm Wires