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Old 05-18-2015, 11:51 AM   #1
1979-square-body
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Exhaust question.

The exhaust I have now leaks a bit so I need to change a few things. My question is how long off the header to the muffler and how far past the muffler will make or retain horsepower? Ideally I would like the muffler right off the head bolts and a turn down right after as long as it doesn't take horsepower away or try valves.

Any input is good
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Old 05-18-2015, 12:34 PM   #2
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Re: Exhaust question.

just curious do you have hooker headers?
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Old 05-18-2015, 12:42 PM   #3
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Re: Exhaust question.

I'm not 100% sure. They are chromed and super close to the block. I haven't lifted the truck to look from underneath yet. I actually need it this week to move some stuff. I'll Jack it up Sunday and get under there to start taking some measurements and I'll look to see if there are any markings.
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Old 05-18-2015, 01:18 PM   #4
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Re: Exhaust question.

Is there an issue with Hooker Headers?
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Old 05-19-2015, 12:26 PM   #5
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Re: Exhaust question.

Anyone??
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Old 05-19-2015, 07:36 PM   #6
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Re: Exhaust question.

Headers have RPC stamped on the outside of the collectors.
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Old 05-19-2015, 07:53 PM   #7
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Re: Exhaust question.

RPC is "Racing Power Company" I remember, vaguely, that they were "decent", but they didn't grab my attention enough to fully absorb them, obviously. Last I remember they were around $150 for a pair of chrome colored "powered coated", (stainless? ) headers.

It sounds as though you have shorty headers? You may need long tube headers....?? [IMG][/IMG]
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Old 05-19-2015, 08:32 PM   #8
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Re: Exhaust question.

The ones I have are the longer ones, they actually come out straight under the truck nearly perpendicular to the ground.
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Old 05-19-2015, 11:55 PM   #9
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Re: Exhaust question.

Okay so the rest of the Internet isnt helping...

It's a center bolt 350, stock carter carb and no emission equipment required.

Given the RPC headers and NO LIMITATIONS, what would be the easiest to put together?

Run straight off the headers? Sure, but will this lend to long freeway driving?

Don't want to bolt together a full from header to end of bed either. The tubes on their now look like pigeon **** welds. I have two mufflers and from the headers back is free.

Again, ANY input would be freakin awesome as I am looking at doing this the days after tomorrow....
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Old 05-20-2015, 02:23 AM   #10
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Re: Exhaust question.

Can you get any pics in the daylight? You mentioned you were going to climb under it. That would help me better grasp what you are seeing....

This is just me...maybe someone else will come along and help out.....?,.,,
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Old 05-20-2015, 06:52 AM   #11
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Re: Exhaust question.

Have you checked your state laws about exhaust?Some states you have to run a full exhaust system to be road legal.
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Old 05-20-2015, 09:24 AM   #12
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Re: Exhaust question.

Photo upload issues.
The site keeps closing when i try to post a link. Seriously with today's web based technology you'd think we could post pics straight from our phones....

Last edited by 1979-square-body; 05-20-2015 at 09:33 AM.
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Old 05-20-2015, 10:00 AM   #13
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Re: Exhaust question.

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Old 05-20-2015, 10:06 AM   #14
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Re: Exhaust question.

So as you can see, the "welds" are horrible. I was thinking a foot of flex tube from the header piece to the muffler and then turndowns right afterwards. I believe the noise level is 4db but I don't really know, or care at this point.
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Old 05-20-2015, 10:47 AM   #15
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Re: Exhaust question.

The biggest issue I think your running into is the transmission cross member. The pipes are run under the cross member rather than over it, which would hide the pipes up in between the frame rails. Are both sides that low ?
If you can wait and see if you can address that issue before doing anything else. They make aftermarket cross members, or hit the bone yards.
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Old 05-20-2015, 10:56 AM   #16
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Re: Exhaust question.

Well the passenger side has a major exhaust leak. I need to fix it now. The truck was like this when I got it. Who ever welded it up didn't use any clamps so I have to cut this stuff apart to reuse the mufflers. Also the dpassenger side muffler is tilted down.

So I am thinking I can cut the tube off the header and reuse the header joint with a clamp and flexible exhaust to hang the muffler higher off the ground.

Oh and the exhaust is hanging by wire too. So needless to say need a few hangers on each side. I want them as short as possible to keep them "legal" but want to increase performance without having to buy a full set up. I'll figure it out tomorrow when I get under there to fix it.
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Old 05-20-2015, 10:57 AM   #17
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Re: Exhaust question.

Also I need to do it as cheap as possible because the funds for this project is drying up...
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Old 05-20-2015, 12:03 PM   #18
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Re: Exhaust question.

The only thing with flex pipe is it doesn't crimp tight when clamping. when used 90% of the time. Try if you can buy a couple of the already bent pieces of pipe to obtain the height you need. Rather than using the flex pipe. It may work out a little easier on the pocket that way. I would try and get the mufflers behind the transmission and dump them out just before the rear diff. If you run turn downs it will help with noise control.

Its a shame your not close to me. I would give you the exhaust off my truck. I took it off during the crate engine install, and I'm going with a all new system.
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Last edited by 1970pelle; 05-20-2015 at 12:05 PM. Reason: added more info.
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Old 05-20-2015, 12:50 PM   #19
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Re: Exhaust question.

I am definitely thinking the same, that it is leaking at those nasty welds. The exhaust is running underneath the tranny cross member. The other fm is correct in that it should be inside/above the cross member.

Back to your question. IF money is the issue, for now, then I say you have the right idea "fix" with the flex pipe until you can get it done the way you need to. As the other fm mentions above, they can leak just the same. And it has happened to me before. Here, the mom & pop muffler shops would fix that for under a $100 bucks just to get you on the road. It definitely would have been much better to have that pipe bent at the angle needed rather than welding it on like that!

Gotta love previous owners.... the genius ones, anyway. lol Goodluck on the temp fix......
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Old 05-20-2015, 02:12 PM   #20
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Re: Exhaust question.

Rez.. I'm not too far away from you. What mom and pop shop would fix it? I can take it there rather than spend more twice.
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Old 05-20-2015, 02:35 PM   #21
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Re: Exhaust question.

Mesa Muffler is always my choice. Small shop, but depending on what it is that needs to be done it's not always the cheapest.

America Mufflers has done similar small work for friends at a decent price, around $100, . Call them Phx shop @(602) 253-4274. or MESA shop at (602) 763-5915

Call both and ask them if they have any way to receive your pictures of the headers/pipe to give them idea and get you a quote before you drive out. I have always known about Mesa Muffler and have used them on 7-8 vehicles or so. They will reuse as much of the part(s) you have as they can, add what you need. America muffler a friend of mine found on Craigslist a few years ago and in my circle their name, referral has been thrown around quite a bit.

The EXXON service station on McDonald Dr. & Hayden in Scottsdale is good about doing exhaust repairs as well. They are also affordable.


Check craigslist if you are near the Phx valley. They're out there. Exhaust system repair isn't rocket science for those that do it daily. If you hit up a Meineke, or ????/_________ other big name places you will definitely pay more.
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Old 05-20-2015, 02:54 PM   #22
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Re: Exhaust question.

And I appreciate the offer 1970pelle.

Rez, I'll look them up. I'm in central PHX.
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Old 05-20-2015, 02:57 PM   #23
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Re: Exhaust question.

You are closer to the America Muffler Phx store. BTW, do you happen to have any of your emissions parts? lol I assume they are in use. If you know of anyone that has emissions pieces for a 1980 Chevy sbc 350, auto 4x4 PM me. I am in need!
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Old 05-20-2015, 03:01 PM   #24
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Re: Exhaust question.

I have the smog pump that's coming off this weekend. Since I am running classic car insurance, I'm not required to run emissions testing.
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