im putting efi manifolds on next week and was wondering what would be better for towing and crusing.......true duels or walker y pipe? any coments or ideas would help alot i want to do it right the first time

 

i'll stick my neck out-

true duals on a six-cylinder is a bad idea in any situation.
three exhaust pulses per pipe is not enough for efficient cylinder scavenging.

 

I tend to agree with rustywheel68. JMO, a 2 1/2" single-out is more than enough. While 2" or 2 1/4" dual outs are nice for the looks, maybe the sound and definitely for bragging rights, they don't really lend much to the performance.

 

I don't see how true duals on a six cylinder is a bad idea if the amount of exhaust flowing dictates that it needs the higher flow rate of true duals.

Quite a few v-twins have true dual exhaust, and it doesn't seem to hurt their performance.

The general formula for exhaust size is dictated by the power output that the motor makes. A nice upgrade for a stock 300 is to go from a 2 1/4'' single pipe to either a 2 1/2'' single pipe or 2'' duals.

If you've got a 300 that has a big carburetor, headers, a cam, over-sized valves, head work, high compression, the works, then it will obviously benefit from true dual exhaust with either the same or larger than stock pipe size.

What a 300 will NOT benefit from, however, is duals with an H or an X pipe. The exhaust pulses on a 300 are very even, unlike those of the V8's, and won't see any real gains in power from an H or X pipe. What they will do though, is make your 300 sound like a 3.8L V6.

 

JMO, there won't be enough difference to make a difference either way. I would certainly reconsider my opinion with dyno print-outs on the various exhaust configurations.

 

im using it alot for towing so back presure is a good thing right? like a 27ft airstream or a 6 horse trailer.....

 

That is a big old load of bull!

You are talking about some very large cylinders. And way too many variables to make a blanket statement like that.

Man my planned system must be a horrible idea. I'm going true dual 2.5" pipes with straight thru Hooker Aero-Chamber mufflers and 3" tail pipes.







No back pressure isn't a good thing. There is a difference between back pressure and exhaust velocity. The velocity is what helps with scavenging. Back pressure helps nothing.

Single or dual exhaust doesn't matter. The size of the exhaust pipe/s does. Going dual 2 1/2" or 3 inch exhaust on a stock 300 isn't going to do any good. It'll hurt performance. Same thing with an over sized single. A dual exhaust with proper sized pipe will perform better then an over sized single. You want to size the pipe big enough to not have much if any back pressure but small enough to keep exhaust velocity up.

Dual 2" or a single 2 1/2" would be a good set up on a stock to mild 300.

 

I agree with Harte, a single exhaust is not only extremely efficient and effective, but it's also a LOT cheaper.

 

There is a difference between that and it being "a bad idea in any situation". Plus a dual set up on an inline keeps the V8 boys guessing!

 

you'll notice i started with "i'll stick my neck out". i was expecting someone to chop it off. that's okay- i do enjoy a good stirring of the pot once in a while.

i'm sticking with my first post until someone proves me wrong.
anybody got Desktop Dyno loaded? I'd love to see the charts.

 

"Plus a dual set up on an inline keeps the V8 boys guessing!" LOL...That's basically what I said..."2" or 2 1/4" dual outs are nice for the looks, maybe the sound and definitely for bragging rights..."

 

i feel like i may have unintentionally hijacked the OP's thread...(sorry).

before we get back into bench racing- are we all in agreement that he doesn't need true duals for towing?

 

no good discution is great....dyno would be cool....

 

True duals are not needed for towing...I don't think they are "needed" at all...but they might certainly be a viable "want".

 

Nope not needed. A single exhaust system will work out just fine.

The whole "want" vs. "need" argument can be said for just about any mods on a 300. So just run whichever one you prefer. As long as they are sized correctly either one works fine.