Header straight into glasspack Qs?

[ks65stang]

The christmas Jeggs catalog has a glasspack muffler called Purple Hornies Header Muffler:

http://www.jegs.com//cgi-bin/ncommerce3/ProductDisplay?prrfnbr=8061&prmenbr=361

This muffler bolts directly to the flange of the header. My thought is to purchase some inexpensive headers for my 289 and bolt these mufflers 3" in 3" out turndown and call it good. I'm wanting to keep cost as low as possible. Will this be extreamly loud and what do you think?

 

[67coupe351w]

WHAT DID YOU SAY?




Yeah that will be pretty loud, id suggest atleast running some pip to your rear axle before turning it down, thats where my flowmasters dump, it helps somewhat having them dump back there.

 

[MustangMatt1966]

I think u are looking for me i have that exact combo hehe well....ask away.and yes it is loud lol loud enough to set off car alarms and make old ladies scream.. but its a great sound, check out my mods and if u have similar ones i am sure u would like the sound....its really deep..kinda like a dragster but not quite lol....i havent had any problems yet, i did it just like u, for the unexpensive costs till i could save up for a good exhaust system

 

[ratio411]

Been there.
It's loud in the car, it's loud outside.
Plenty of drone to give you a headache.

There is also the issue that glasspacks 'burn out' or 'blow out'... whatever term you use, when placed too close to the headers.
They will not last as long as mufflers placed further back, so you are not really saving money.
Dave

 

[calpolymustang]

The statement on the Jegs website about back pressure is only a good thing if you are running at higher RPMs. An engine does not run at one RPM or at one load amount. On a 289, backpressure can be your friend when you are taking off from the line. Without backpressure, you lose effects like 'scavenging', where the flow of one cylinder's exhaust helps to pull out the air in another cylinder.

If you want some bottom end torque, put in an H-pipe and then the glass-pacs. Dump the exhaust down near the rear axel, but not too close unless you want a dirty axel.

One time, I ran open headers with no exhaust. My bottom end acceleration was lost. Sure, it idled like a dozen harleys, but the rest of the exhaust helps to pull air out of the engine at low rpms.

My roomate interned at Garret Turbo-chargers this summer so I'm always learning from him about boost, vacuum, and thermodynamics. We have both seen naturally aspirated performance setups where guys have drastically changed the intake vacuum pressure just by redesigning the exhaust. My point is that less exhaust is not always a good thing.

 

[ks65stang]

Thanks for all you comments, I knew I wouldnt get away doing it the cheap way. Summit Has a house brand headers, turbo mufflers and dual pipes that exit near the rear tire for a decent price ($200?). Which setup do you think will sound and preform the best, Thanks.

 

[calpolymustang]

i had the super turbo dynomaxs and they sounded decent. they would quiet off on the freeway and get loud under acceleraction. i eventually bought the 2-chambers and WOW, that hollow/throaty sound of the flowmasters is a darn good sound. though it gets loud outside, i never get headaches. this is partly because i ran the tail pipe all the way to the back. if you run 2.5 or 3" pipes, they will be louder and resonate at different frequecies than mine. 2.5" with super turbos is a good and inexpensive way to go, but you wont be setting off car alarms. go with the 2.5 piping lit and later if you want it louder, upgrade the mufflers to flowmaster.

the long tube headers they have will probably be fine for a mild engine

as far as exhaust gaskets go, the cheap ones often leak. i say also buy from summit some lead or similar gaskets (the reusable ones that are of a soft metal)