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I am in process of a 1950 3600 build with a 383 SBC that originally was a 350 in a 1991 Chevy 2500 truck.

I am aware of the driver's side exhaust manifold to steering interference issues but have not decided which route I plan to take with the steering: original relocated outboard, 67-87 Checy truck steering mounted outside the frame but further forward, or ??

I was previously advised that a 55-57 265 exhaust manifold could be used with the original steering gear as it locates the discharge forward.

However, I have determined that the passenger side 1991 exhaut manifold will not clear the frame. The discharge flange are is interferring.

To resolve the passenger side and possibly give some direction to the driver's side I am considering going with rams horn center dump 2 1/2" manifolds that I have used on a previous SBC transplant in a Jeep Wrangler. I am not planning to use headers for a variety of reasons.

Any insight regarding Gen 1 SBC exhaust manifolds that will clear the frame would be greatly appreciated.

Have you considered the exhaust manifolds used on the early 1980's 305 engines, the ones that have a rear exit at around a 45 degree angle? With a little creative pipe bending by a good muffler shop, it's possible that your frame and steering system clearance issues could be solved that way. We used those manifolds on "claimer" race engines in a class that didn't allow headers, and until the RPM really got high, there was no appreciable loss of power compared to ram's horns. There's also a set of exhaust manifolds that have a 90 degree rear exit.
Jerry

Another option would be using 2 straight down ram's horns and set the engine up off center toward the passenger side.
Hundreds of thousands of trucks came that way believe it or not. Since you only need between 1 1/2 to 2 inches offset to clear the steering box, your u-joints will not know the difference as long engine is installed with the crankshaft parallel to the pinion shaft.

Thank you for the suggestions.

Hotrod, do you happen to know the casting or part number for the 80's 305 manifolds? My exhaust is going to be custom anyway but the flanges need to clear the frame.

52Carl, I was anticipating if I go with ram's horn the outlets would be straight down. My engine is already mounted and centered so I don't think I can shift it over. I am not even sure that the straight down ram's horns will clear the frame with the engine centered as I was surprised the '91 passenger side manifold did not clear, although it is not a block hugger by any stretch of the imagination.

WICruiser,

I think that these (see link) are what HRL may be referring to.

https://www.dormanproducts.com/gsearch.aspx?year=1984&make=Chevrolet&model=C10&origin=YMM&parttype=Exhaust%2520Manifold (copy and paste to browser)

In comparing these manifold photos with your previously posted "trial cab fit" install pictures showing engine location, these might be just what the doctor ordered.

Let us know how things turn out.

Dan

Here's a couple of different designs with a rear outlet:

https://www.ebay.com/itm/165075822757?

https://www.ebay.com/itm/164090511703?

Search "305 Chevy exhaust manifolds" on Ebay
Jerry

Thank you for the additional insight. Guess I have a decision to make.

Looking at the various options the manifolds that have a rear discharge angled about 45 degrees would appear to aim directly at the cross member that was originally the rear engine mount and reinforcement for the frame associated with the front leaf spring anchor. Rear discharge that are more or less vertical appear to put the discharge in proximity of the oil filter on the driver's side and starter on the passenger side. None of these concerns are insurmountable but the straight down discharge rams horn manifolds are becoming a more likely choice. I envision the exhaust pipes would run virtually straight back, slightly below the frame minimizing the number of bends and conflicts.

Any additional insights regarding my selection and thought process would be appreciated.