Exhaust for a slant

[70DusterGuy]

Well I am gonna have some new exhaust put on my 70 duster with a 225. I need to know what are the best mufflers and pipe size? my plan right now is dual 2 1/2'' out the back with an x pipe and a good set of magnaflows with rectangle slant down tips. Also I have bored it 60 over with a new cam, bigger valves, .010 off the block and .080 off the head, offy dual one's and clifford headers. If anyone needs to know. Tell me if I have anything wrong in my thoughts.

 

[RustyRatRod]

Duals for a slant at your level is way overkill, IMO. I think it will respond much better to a well thought out single exhaust.

 

[70DusterGuy]

Alright well I trust your opinion. Will it make the car run any worse with dual, or more of a just really doesn't need it type of thing?

 

[64ragtop]

The car probably won't run any worse with duals, but they'll cost more for not much (if any) benefit. Look up Aggressive Ted on Slant6.org. He thoroughly explains how he built his single exhaust. If you really need the dual exhaust tips, the passenger side doesn't have to have a pipe attached!

BC

 

[mowrycuda68]

I run the Clifford headers out the side with dual cherry bombs. MY neighbors love me... :la:

 

[vynn3]

Single exhaust with a dual-outlet muffler would be cheaper with less weight. Just make sure you have a competent muffler shop who's willing to run two tailpipes off the single muffler (make sure they look at it before you spend any money).

 

[2 Darts]

I've got a 2¼" single all the way with a Dynomax on my '73 /6. Stock motor and a 904. Sound is satisfactory under acceleration, fairly quiet under cruise. I am using an oversize exhaust manifold that has a single 2¼" outlet so the straight 2¼" made sense to me.

 

[BillGrissom]

Duals are mostly for looks. The first Dart V-8's used a single exhaust, even in the Commando HiPo version. I read that they tested a dual setup and found the single made more power. In the 70's, many speed places offered "4 into 1" exhausts for Japanese motorcycles, claiming 25% more power. When Honda later designed a 4-into-1 exhaust, the same companies started selling individual pipes, with the same claimed 25% power increase. What do you infer from that?

 

[Sick_Six225]

This is what my 72 Dart sounds like with one flowmaster and one pipe dropped at the back axel.

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[2 Darts]

Duals are mostly for looks. The first Dart V-8's used a single exhaust, even in the Commando HiPo version. I read that they tested a dual setup and found the single made more power. In the 70's, many speed places offered "4 into 1" exhausts for Japanese motorcycles, claiming 25% more power. When Honda later designed a 4-into-1 exhaust, the same companies started selling individual pipes, with the same claimed 25% power increase. What do you infer from that?

I infer that it's all BS at worst, and a matter of preference at the most generous I can come up with. Definitely so at the street level.

Consider that all racing cars but the fuel burning funny cars and dragsters use some sort of header system. A lot of this is specified by rules, so this isn't necessarily a valid comparison. Just something to think about

 

[demoman3955]

doing exhaust for over 20 years , i found what they say is true, which is :

larger pipe (more flow) = less low end, more top end, less clearance
smaller pipe (less flow) = more low end, less top end.
Duel exhaust (more flow)= less low end, more top end, less clearance, less money in pocket.
i put a 2 inch on my 6 and it runs fine, but then its mostly stock.

decide what the car will be used for and go from there.

 

[mowrycuda68]

I wouldnt do dual exhaust unless you so everything else. like oversized valves, ported head, bored cylinders, a good two or 4 bbl carb/ aluminum intake, and of course a good cam. Unless you do all that it would be pointless to go dual exhaust or even large diameter single. Stock these engines just dont flow air very well but if you open it up then..rayer:. I have all this done to my slant six and I drive it on the street. It hauls *** and is very loud if I step on it. as for loosing top end HP with dual exhaust. I really couldnt tell you. I think the difference is in how you build the engine.
:thumbrig:

 

[64conv65hard]

I put Dutra Duals on my 65

 

[Duster666]

I ran 2 1/4" from my Clifford headers, with Solo Mufflers. Mainly for looks, and sound. All custom between the Headers & Mufflers.