I was going to buy a Pypes SS exhaust system for my wimpy 1979 305 Camaro and one of the Pypes technicians said the exhaust was too free flowing and would not keep enough back pressure on the engine causing it to lose power.

I'm not real knowledgeable about this engine (other then most would say dump it for a 350) and know it is a dog but is this true? I thought getting more flow from the exhaust would help get a little more power.

Here is a link to the exhaust system. pye-sgf70s Here's what he suggests which is not like the original system. pye-sgf911te

Anyone here support his comment on putting this exhaust on my 305? I'm trying to keep it as stock as possible and this muffler looks very close to OEM.

I appreciate any comments!

 

Frankly I wouldn't waste a dime trying to get more power out of a 305,for what that exhaust system costs you can put a fresh 350 in your car and have more power even with stock exhaust. Then you have something to build on,headers on that 305 are a waste of money.

 

I really like your Camaro! I have a 1997 30th year anniversary one that looks and runs good but my 79 needs a new exhaust system.
I appreciate your honest answer but it’s not headers…it’s a new stainless steel muffler system. The current muffler is rusting out.

Anyway I’m retired and don’t have the money or skill to drop in a 350. At this point in time I am trying to keep it as close to stock as possible. The car is 42 years old and basically in mint condition with 22k miles.

So regardless of the fact it needs a 350 but has a non ECU 305 would a more free flowing muffler system make the engine run better or worse? I just don’t know enough about how back pressure affects how an engine runs. Anyone here know. Thanks!

 

Probably wouldn't make much difference either way,my advise is find a local muffler shop for a stock type exhaust.
Probably less money and you won't have any issues.

 

The whole “you need back pressure” thing is a myth. If you could vacuum out the cylinder your motor would run more efficient. There is plenty of info on the net debunking this from exhaust engineers. I do not blame your tech tho, an old timer well respected GM tech told me the same thing back in the 80’s.



Now after saying that, your car from the factory has some restriction. First would be the Cat, then the cast iron exhaust manifolds then last would be the exhaust itself. Making the exhaust system breath better without addressing the Cat or the Manifolds is only going to change the tone of the exhaust.

The nice part about doing exhaust work is it will all transfer over to a 350 when you get there. For what you are paying for that Stainless system you could buy aluminum coated headers and exhaust. They can have a 12 years life span even up north as a daily driver. Easy 20 years as a weekend cruiser.



The 305 was GM answer to the emissions/fuel milage problem. GM lightened the block as much as they could. This resulted in a very weak block. So not only are they low HP from the factory if you add too much power to them they will fail. Back in the day when the 305’s where new and under warranty we use to see spun bearing in them all the time. I put many crank kits in these motors under warranty.
The only time I can remember the 350s failing it was because of an external reason. Engine was run low on oil or a thermostat stuck that caused an over heat, something like that.

 

Hey...thanks guys for your opinions and the information! I'm going to try and get a new exhaust system installed next Spring before all of the local car shows start back up here in NE Ohio.

COVID killed them here this last Spring/Summer so hoping 2022 is s great year for the local car shows again!

I have time to think about your suggestions and will post back here after I have made my decision and have it installed.

Gorn your 67 Camaro is a beauty!