Porting stock exhaust?

[LukeZ]

hey all, just wondering if someone could shed some light on how to go about porting stock exhaust manifolds. I go on spring break next Friday, so I thought it'd be a cool little project to do over that time. Other than a set of wrenches and a carbide burr and maybe angle grinder, what tools would you need? I've never messed with the engine bay at all, so I have no experiamce removing stuff. Is it best to remove the manifold from the bottom and not the top?

I figured if someone could maybe give some general step by step instruction, then that would help out us idiots who know nothing 😛

Also, is this a job that could be done in a day or two? Thanks

 

[lilbowtie]

My first question would be why?? And google is a great friend.

 

[LukeZ]

My first question would be why?? And google is a great friend.

My response is why not?

And I couldn't find anything on Google.

 

[565bbchevy]

Well I am going to say this is probably not worth the effort and I doubt you will see ant improvement over what is already there.
And you could end up creating more problems if you end up breaking something like exhaust studs or stripping bolts remember most likely this stuff has not been removed in 30+ years and is probably rusted.
Now if you were upgrading to headers and free flowing exhaust then I would say go for it.

 

[lilbowtie]

Don't know if you are running a class that has to run stock manifolds - are you turbo charged ? If you are running aftermarket heads by all means you need to port match. But if you think your going to unleash some power on a stock engine, I'm with 565. Real power is in the heads

 

[LukeZ]

Hmmm... Are shorty headers any good for a stock 305? I found some from Ecklers El Camino Store that come with studs, nuts, and flange gaskets. They are 180.99 per set (black, not painted or chrome). I guess an exhaust shop could install them and hook them up to my current exahsut without much modification for only a few hundred dollars?

 

[565bbchevy]

Other than stock exhaust manifolds what does the rest of your exhaust system consist of?

 

[LukeZ]

Other than stock exhaust manifolds what does the rest of your exhaust system consist of?

2 1/4 pipes all the way though. Stock cat (which I was going to replace with a brand new spun cat soon). Exhaust cutout from QTP right after the cat. Flowmaster 80 series muffler with single inlet and dual outlets.

 

[565bbchevy]

2 1/4 pipes all the way though. Stock cat (which I was going to replace with a brand new spun cat soon). Exhaust cutout from QTP right after the cat. Flowmaster 80 series muffler with single inlet and dual outlets.

So is this a Y pipe going into the cat? And does it split after the cat to dual exhaust?

 

[LukeZ]

So is this a Y pipe going into the cat? And does it split after the cat to dual exhaust?

Yes, y pipe to cat. Splits at muffler, which has one inlet and dual outlets