[1978ramcharger]

By true dual exhaust, I mean headers down to indivudal cats and mufflers and out though individual pipes. Would the extra expense of doing this, instead of dual to single to dual, really be worth the money. How about on gas and hp? Does anyone have true dual that used to have "fake" dual-- is there a difference?

 

[CLRracer]

depends on what u want from the truck. i have been told that true duals are good for higher RPM horespower, but one big single exhaust is good for low end torque.

Duane

 

[macario]

I've got a true dual exhaust but mine comes out of stock cast iron into separate pipes, no cat on a 76 RC.

As to whether it is worth the money, only you can say if it is worth it to you. It will sound better, you might notice a difference or think you do. The only way to tell for sure on your vehicle is to take some 0-60 times before, then some after the switch.

I'd say if you have the money, go for it - get the "real" dual exhausts.

By true dual exhaust, I mean headers down to indivudal cats and mufflers and out though individual pipes. Would the extra expense of doing this, instead of dual to single to dual, really be worth the money. How about on gas and hp? Does anyone have true dual that used to have "fake" dual-- is there a difference?

 

[Grayguy]

Don't true duel systems usually need some kind of H or X pipe?

 

[macario]

Cross-over pipe would be nice addition.

Don't true duel systems usually need some kind of H or X pipe?

 

[CLRracer]

its not needed, but it helps.

Duane

 

[Trailduster_Rulz]

I'v ran both true duels and the y-pipe into single muffler with duel outlets. As far as I am concerned I wouldn't say that one is better than the other. On the other hand running a duel outlet muffler allows you the same effect as true duels with a X or H pipe in it and would be cheaper especially if the cats are a required item. In the end it ultimately comes down to what you personally want.

 

[1978ramcharger]

i want hp and an extra mile or two to the gallon

 

[DDGRC84]

have you looked into the part-time conversion kit i told you about?

Jake

 

[Major Ramifications]

I went from factory single exhaust to true 2-1/2" duals with Super Turbo mufflers, no catalytic converter, and a crossover pipe. On a stock '89 318 with EFI, this was good for 2 tenths of a second in the quarter mile (if I remember correctly). It was worth it to me, because I needed to replace my rusty pipes and muffler anyway, but to get the full benefit from the new system, I would have needed to do some things to wake up the engine.

 

[1978ramcharger]

yea, i did look into that mile maker kit--its so expensive. like 500 bucks.--maybe someday, I just spent 500 on my eddy q-jet and about to spend another 500 on this 'true" dual exhaust system.

 

[spittindurt]

Ive got dual 2 1/4'' into 2 2 1/2'' cherry bomb glass packs with no tailpipe (end of pipe just behind cab under truck) but the only reason I did this was to make it loud and its plenty that, almost to loud cant hear my music at 70mph on the highway, oh well guess I'll just have to suffice with makeing those 4banger motors sound like toys

I plan on getting some headers into a dual 2 1/2'' or 3'' with some flowmasters just for kicks and giggles. And meaby more loudness

 

[78machowgn4me]

are there any manufacturers out there who make "true" dual exhaust for 78 power wagons? the biggest problem would be the standard gas tank mounting position (side of the frame). anyone got an idea?

 

[jpryorx2]

i got headers with 2.5 in pipes into flowmasters no cats didn't notice a performance difference but picked up 3-4 mpg and a nice sound over all it cost me 500 bucks i put the headers on my self and let a shop bend the pipes up i'd like to ass a h pipe but don't know if it's worth it.i know if i drive with my hubs locked i get half the mpg.so it might be worht the money for the part tme kit

jason

 

[BrianT]

Hey 78 u have ot run the duals outside the frame rails . If oyu ask me it is way cheaper to use single in dual out muffler . it's what all the newer rigs have and they all sound pretty damn good . just my .02 cents and doing it this way is hella cheaper and u still gain some performance as u would with true duals . U might loose 5 hp maybe

 

[lost1]

any way you can get the spent gasses out fast means more power and better economy. duals are good, but then you may want to increase the air mixture in, then the gasses out.... mean cycle.

 

[Smokey]

A couple of years ago we held a VERY long discussion on RCC, with people citing actual chassis dyno numbers and quarter mile ETs, as well as some fluid dynamics input from the egghead engineers amongst us, and a briefing on reversion wave exhaust tuning from me. I think the thread got lost in the server change, but the result was:

Headers "Yed" into a single 3 inch, with a 3 inch high flow cat and Dynamax (or similar) muffler will give you a bit better performance and mileage than two 2.5s. Do the math on the flow capacity (volumn of a circle versus the internal surface area), and you'll see why. The main reason for one large single is the ease of routing the pipe.

The slickest set of true duals I've ever seen were paralleled down the same path that the factory single runs, with dual high flow cats, then a long low angle 2.5 inch diameter "X" pipe in line near the trans/transfer case, and the mufflers staggered one behind the other so the system would take up less space. Sounded great and ran good. Was expensive ~$600 complete and installed. Passed Smog test.

 

[Firechicken]

I went from factory single exhaust to true 2-1/2" duals with Super Turbo mufflers, no catalytic converter, and a crossover pipe. On a stock '89 318 with EFI, this was good for 2 tenths of a second in the quarter mile (if I remember correctly). It was worth it to me, because I needed to replace my rusty pipes and muffler anyway, but to get the full benefit from the new system, I would have needed to do some things to wake up the engine.

Well thats a good gain 2 tenths is equal to around one car length difference right on man! Mike.

 

[v737d]

Like most things you will have to change other things on your motor to gain the full benifit of a true dual system. For best effficiency you will want a x or h pipe in there as it helps scavange exhaust out from the opposite cylinder bank. Will cost a bit more and you will want to consider the extra work involved with removing all of that xor h pipes if you have to drop the tranny, or x case.

My two cents...go for it! shop around you will probably find a wide range of prices for the work. If you really want the best make sure the pipe benders are using a mandrel machine so the pipes don't get pinched down in diameter with each curve.

Cheers

Chris

 

[JaMeS318]

I had fake duals with a glass pak and no cat. It was ok but not loud enough and i wanted a performance gain. SO i put headers on. It was a lil gain. THen about 2 weeks ago I went and had true dual 2.5 inch pipes run outside the frame rails and exiting in front of the rear tires. I gaurantee that i made a noticeabel gain. I feel alot more power down low you can really feel it when you hit second gear at wot. Feels almost like getting shot out of a gun lol. I went from not bein able to spin my bfg at's on wet pavement. TO bein able to give it quick gas mash it half way down and break the back end loose. THat is a gain in my book. I think my mileage actually dropped a lil. But it sounds so much more healthy no than it did. SOunds like a different truck. Mad a big diff in throttle responsce also.