Just bought a 68 GTS Big Block. It has , I am told, a set of incorrect exhaust manifolds on it currently. In the market for a factory correct set of exhaust manifolds......here's my question....am told my manifolds are not the factory stock manifolds....may be off a truck.

How critical is it to have to proper factory manifolds? Are there performance issues to be concerned about?

Is this an issue "if it fits then they are Ok or do I need the correct manifolds?

Thanks

Big block a-body exhaust manifolds are the most restrictive.The bend in l/s is a killer. Do you care about being correct and hearing for the rest of your life they're wrong? If not, and they fit enjoy.

Unless you are a purist, if what you have works without any interferences or overheating of other things, I'd keep running them. The stock LS manifold is really a piece of crap. IIRC, the manifolds dropped the power on the motor from 335 to 330.

Pics sure would help. Truck manfolds are not that great either, and I can't believe they work on a Dart. I have seen B-Body HP manifolds used but some modification is required.

TAKE A LOOK HERE.....not sure if you can tell by these pictures or not

https://picasaweb.google.com/114420406354641747303/1968DartGTS3834Speed?authkey=Gv1sRgCNj_sLOm2sjqYg

Greg

Those are truck logs, lo po but they are not killing you. Look for some Hi-po B logs that have the outlet behind the #7 port, much better and I think they even fit. Dart B manifolds are expensive and flow bad.

Thanks.....So what you are saying is the correct manifolds potentially have more restriction?

THe drivers side has restriction because it wraps around the steering column. They are not as bad as most people think, they are find for the street. I have owned big block A-Body's for 35 years and can tell you the stock manifolds are fine for a street driver. My stock 69 383 4-speed GTS was good for 14.91 in the quarter, biggest problem is traction!

Thanks Jim.....know of any stock big block manifolds available?

Greg

There is a set of 69's on eBay right now, though the passenger side is actually a B-Body piece. I do have an extra set, but keeping them right now for my M-Code unless I find the elusive drivers side M-Code manifold...

The pass side from a 67-71 magnum has worked on any BB A body I've ever done. I used a milled C body on a 440 RB in a 73 Duster but I whittled a bit of the steering column :-O

Something I thought about doing was to section a pair of C body logs to use the back half of the pass side for the 1-3 cylinders and the back half of the 5-7 on the drivers side cast welding them between the 3-5. You would need to route a 2" front outlet around near the K and Y the 2 driver side pipes together, but in theory I still think it could work and be Kinda cool. Do it well enough and somebody at the car show will brag to his friend that it was a rare 'factory option' :-)

This was way before the Schumacher tri Y's which are really the best solution for a mild big block.

Thanks WIZE....a lot to think about

G

I remember there was a guy on the Philly street racing scene back in the day that had taken a passenger side manifold and put it on the drivers side. The exhaust pipe dropped straight down through the K frame. At the time I thought it was pretty creative,very cool for a low buck solution.

Accurate made a c-body manifold that works good, they welded a tube down pipe. I angle ground a 68 hp c-body to fit around the steering.

I had a 68 GTS 383 car back in the day (76) i put a 440 in it & under acceleration the manifold got bound on the steering shaft! That made it interesting unless you were pointed in the right direction! I still have the manifolds as I replaced them with fender well headers.

Sold the car in 78 & it was wrapped around a tree within 2 days!

When Dad was restoring his 68 Dart GTS 383 Ragtop he bought as a basket case, he opened the trunk and there in mopar OE boxes was a set of new manifolds, they put a 440 in the car as the origional 383 was a few states away and they didnt want to go digging in the guys back yard for the engine, well long story short, a complete low live A hole stole those exhaust manifolds from Dads parts shed on the farm back in the early 90s. He knew where they were and what they were because he needed a set and was looking around, Dad made the mistake of telling him where they were. The great dane that usually guarded the place was sicker than hell at the time so he managed to get them alive.

Im sure Dad is haunting that man right now because that always bothered Dad every time the manifold story came up.

I keep my m-code set under my bed and my 45 cocked, paid 45 hundred for them, they were used for 13 miles then taken off for headers on a dart