Hi guys,

I've just been reading through numerous posts on headers here and have gotten a lot of information. I still have a question though...
From what I gather long-tube have clearance issue but better performance. Shorty's don't have the clearance problems but you sacrifice some hp. Is this true?

Some info about my car: 305 TPI stock. I plan to upgrade to a 350 cu engine down the road and in the end I'd like to push 350 - 400 hp. It would stay a street car and I would cruise around for fun. I plan on getting a magnaflow cat + flowmaster cat-back.

Also, I don't want to have any obnoxious sounding exhaust system in the end. I'd like it to have that deep low rumble that I seem to hear most of the time on Mustangs. I've seen a lot of cars running open exhaust that I just cannot stand. I want this to be a respectable street car that doesn't sound like I should be at the strip.

Ideas? I'm looking at either headman or hooker headers.

Thanks,
Jeff

 

If you aren't looking for more than 350-400 hp, shorty or mid-length headers will be fine. A 1 3/4" primary would be the right size for a 350 putting out those numbers, but it would be overkill on your stock 305.

How long before you make the swap?

- Justin

 

If ride height is going to be an issue then stay away from LTs. If your car is lowered, or will be, and you are concerned about speed bumps, driveways, etc. LTs will not be your friend.

As for shorties, you do give up a little horsepower but for the piece of mind of knowing you wont be dragging your expensive LTs across every bump or driveway definitely makes them an attractive option.

BTW, I am going to be using the shorties for the reason listed above, and I am ok with leaving some horsepower on the table for piece of mind.

 

Justin,

Thanks for the tips, I plan to swap the 305 to 350 in anywhere from 1 - 2 years. My plan is to get a used block, have it cleaned-up and start building from there. Hopefully after a couple of years of slow build-up (small budget constraints) I'll be ready to drop it in.

When you say that 1-3/4" is over-kill for the 305, does that mean it will hurt performance? I think I saw another posting say that a 1-3/4" on a 305 was only a 10hp gain, but a 1-5/8" on a 305 got a 15hp gain.

Does this sound about right?

Jeff

 

This might help you put this business in perspective. The late John Lingenfelter said that he kept to 1 5/8" headers until his engines reached at least 400 hp.

Thus the idea of 1 3/4" headers being overkill. Fit your needs into that equation.

I've seen engine tests where 1 1/2" shorty headers provided more useable power on a 383, under 5500 rpm. Who needs to rev higher than that on the street?

 

I have hedman long tubes, they were 135 new from summit and although my car isnt lowered, i dont have any problems scraping the ground....

 

Thanks for the rule of thumb. I figured there had to be some type of equation for selecting primaries.

One more question though, what would the best collector size be for my application? 3", 2-1/2", or another?

I'm inclined to say 2-1/2" becasue the single CAT system I'm replacing will be 3" and two 2-1/2" pipes feeding one 3" outlet should be perfect. I think going to to 3" collectors would be a waste.

Right?

 

On a 305 shorties will be fine. On a 350, you are gonna want long-tubes. DEFFINENTLYO go w/ 1 5/8 primaries. The only time you want 1 3/4 or larger is on a 383 or larger

 

What about collector size? Should I go 3" or 2-1/2?


- Jeff

 

Under 5500, where are you driving. I am a firm believer that ALL street cars should be able to rev 7000...thats just me though. I would think about your plans for the car, if you plan on making some power in the future get what you will need for that. I don't see the point in buying headers 2 times. BTW I had hedman LT's on the old formula with the 355, they had PLENTY of ground clearance they are 1 5/8' primaries, and 3" collectors. I think they would be great for a stout 305 or mild 350...I just don't think shorties are worth the time and trouble of putting them on.

 

I would go w/ a 3" collector

But 89385formula, I had NO problems what-so-ever putting the shorties on my car. Then again.. my engine was completely torn-apart from the rebuild when I put them on

 

This brings up another question which I had not thought about yet.... What are the installation issues with each: LT and Shorty?

I would have guessed before this that the Shorty would have been the easier set to install. What are everyone's experiences installing Shorty/LT headers? Did you encounter anything that required mods of other parts?

 

My Lt swap was a cake to install. Shorty headers have poor plug access, and don't give much of a gain.

 

Shorties on a 305 will give you alsmost as much gain as long-tubes. Especially if your not pushing super-huge ammounts of hp. But my shortie header install was a piece of cake as well, but there is one HUGE downside; If you have A/C, you will have it no more unless your talented enough to somehow work around that I am so pissed I dont hvae a/c anymore The bracket wont mount w/ the head if you use the Hedman shorties.

 

Wow, this is one big downside. Well, I absolutely have to keep the A/C. Will you lose it only when using shorties? Or does it vary vendor to vendor? (i.e. will hooker shorties still allow the bracket?)

As far as LT vs. Shorty goes... I'm leaning towards LT now since I plan to move to a 350 down the road. As long as I don't loose any performance on my current 305, that should be ok.