Question: funky exhaust system opinions wanted

[89AKurt]

Previous owner had a new exhaust system installed, am thinking about a few things, need technical questions answered (?), and what might be a better option(s).

The heat riser valve (that what it's called?) is so rusty, it does not move easily, have in permanent open position. It starts fine, since I replaced the distributer and Holly carb.
(1) Do I really need it?
(2) Wouldn't it breathe better to have the 3" pipe go all the way from the header?


Again, they kept the original size pipe, that looks restrictive, obviously to squeeze past the starter. I read in other threads that headers running too close tend to fry the starter.
(3) Can't insulating tape, or a tacked on metal shield work?


Some of you may be shocked about this, they torch cut through the cross member.
(4) Should I be worried about this weakening the frame? Another thing that bugs me, is how the parking brake cables slide over the pipe, which could wear a hole eventually, and the pipe is rubbing on cut hole.
(5) Is this a good way to have more ground clearance?


I'm not interesting is restoring to original, but I do want to improve whenever possible. Would like at least to have 3" pipe to the header. Also have a weird desire to have the pipe terminate before the rear wheel, maybe on the driver side, just so I can enjoy the sound (a little different than the whiney whoosh of my MINI). LOL

[Grumpy old man]

Thats a pretty butchered looking exhaust , buy a heat shield from summit for your starter then take it to a decent muffler shop an have them install a 2 1/2 inch system and remove the heat riser , that will handle any street engine also the cut thru cross member was to keep the system up high and won't hurt anything. A real muffler shop will probably install your heat shield for you while it's on the lift .

[89AKurt]

Originally Posted by Grumpy old man

Thats a pretty butchered looking exhaust , buy a heat shield from summit for your starter then take it to a decent muffler shop an have them install a 2 1/2 inch system and remove the heat riser , that will handle any street engine also the cut thru cross member was to keep the system up high and won't hurt anything. A real muffler shop will probably install your heat shield for you while it's on the lift .

LOL The guy I got the truck from said his grandpa half-assed everything.
Thank you!

[jerry moss]

one thing to consider when going with larger diameter pipe, you will kill the low end torque on a stock small block. a gas motor needs some back pressure unless you're running a big cam and lots of horsepower. i get people all the time thinking big is better but with a fairly stock motor it aint so.

[Lattimer]

The pass through the crossmember is pretty typical for lowered trucks. Most people weld in a pice of steel pipe where they make the hole to reinforce the crossmember.

Otherwise, what you have there is a pretty hacked up mess. I'd take it to a reputable shop and have them do it all over in 2-1/2" pipe.

[89AKurt]

Thanks Jerry Moss and Lattimer. I see a consensus on hack job and 2 1/2" so far.

[special-K]

Jerry is right (this is what he does). I'd have dual 2 1/4" exhaust run. If you are staying with cramming it all in one pipe, then I'd go bigger. 1/4" is a lot more volume than most think.

[swamp rat]

Look at the chart on this page and one can quickly see that on a stock SBC engine anything over a dual 2 1/4 is not helping flow requirements.

Jerry Moss is correct on loosing torque, plus the back pressure helps aid in scavenging of the exhaust.

http://www.exhaustvideos.com/faq/how...pipe-diameter/
.
.
.

[Already Gone]

My 72 with a bone stock 350 and 350 trans had duals when I bought it. Someone had cobbled a dual exhaust system on it by cutting off the y pipe half way down and pinching it off. Then they just ran an exhaust pipe from the pass side exhaust manifold to the back of the truck and there were 2 different sized mufflers on it. I'm not sure what diameters of exhaust pipes were on the truck but they were different sizes with the pass side one being smaller than the drivers side. I had the whole system replaced with a pair of Dynomax Super Turbo's ( see link ) with an " H " pipe and 2 1/4 exhaust pipes running right to the back. The truck runs much better now and sounds ( to me ) like a V8 4bbl dual exhaust vehicle should sound.


http://www.dynomax.com/super-turbo-c...ffset-596.html

[89AKurt]

Originally Posted by special-K

Jerry is right (this is what he does). I'd have dual 2 1/4" exhaust run. If you are staying with cramming it all in one pipe, then I'd go bigger. 1/4" is a lot more volume than most think.

Seeing that you have posted a billion times, appreciate the confirmation.

I like the idea of twice pipes, with a cross over. If I go all the way to the back, will be tempted to add flame thrower device. >:^O

[cleszkie]

Also consider re-routing your fuel line away from the exhaust pipe, or placing a heat shield over it. Looks pretty close in that picture.

[dmartin1]

im very guilty of butchering some exhaust myself in a pinch, but yes i would rip that out and route a fresh system.

Im just weird with exhaust though too,even though little to none will ever see it, just knowing its not symetrical or goobered drives me crazy.


best of luck!

[89AKurt]

Originally Posted by cleszkie

Also consider re-routing your fuel line away from the exhaust pipe, or placing a heat shield over it. Looks pretty close in that picture.

Oh heck ya! That's been project #88 for awhile. LOL That was much worse when the saddle tanks were installed, plan to put mechanical pump back on engine, and use metal fuel line for this section.

[89AKurt]

Originally Posted by dmartin1

[...] even though little to none will ever see it, just knowing its not symetrical or goobered drives me crazy.
best of luck!

Understand! The longer run from driver's side joining together is a great reason to replace, thank you.

[Step-Ed]

I had the same rusty pipes, and not a logic route. I went to a shop and they make a rvs systeem in front of the wheels. Great sound and beter route.

[89AKurt]

Step-Ed: That looks nice! So no cross-over pipe?

[Step-Ed]

I don't think it will benefit the engine. It is a stock 350, not a performange engine. And I think it sound beter without it.