Ram horn exhaust. Which ones?

[chalet2506]

So now that I've got my engine build coming together, I need to decide on exhaust. 400sb with vortec heads. Definitely want to go with 2.5" ram horns, but I can't seem to find part #'s in any of the threads that I have searched.

Dorman 674-503 is passenger side for a 1965 Vette. I believe this is what I need and the shop will machine the alternator bracket when it gets here. Looks like driver side is out of stock until June, so can I just use 2 passenger side? I'm guessing bolt holes and exhaust ports are the same pattern for both heads, not sure though.

Or, All Star performance makes some good looking manifolds. The cost a little more and looks like they would be a tight fit. Was wondering if anybody here is running them.

http://www.allstarperformance.com/product.htm?prod=718&part=ALL34200&add=no

 

[76zimmer]

IF you machine the alternator mount, they will interchange side to side, as they both dump in the center.

 

[bp71k5]

IF you machine the alternator mount, they will interchange side to side, as they both dump in the center.

X2, that's what I'm using on mine. They work great, but make sure you run spark plug wire protection on the two plugs next to the outlet. I've burned the rubber boots on two sets of wires so far.


-Brian

 

[chalet2506]

Went ahead and ordered 2 of the 674-503 passenger side manifolds this morning. No heat tube risers, and I will have the shop clean off the brackets and also machine the mating surfaces so they don't leak.

Now I need to find something to paint or coat them with.

Probably going to buy some stock heat shields to protect my plug boots.

 

[bp71k5]

Probably going to buy some stock heat shields to protect my plug boots.

I'd be curious to know where you get those...




-Brian

 

[shady]

Why would you have to machine anything to make them seal?? I always thought that the whole reason for going to the cast manifolds was to get a reliable seal. I've been looking to uprade in this area too (still stock). I love those from allstar. I wonder if they would fit a burb

 

[chalet2506]

I'd be curious to know where you get those...




-Brian

Well crap, thought I had seen them in LMC catalog. May just have to try and reuse the ones that are on the truck now. Or if they are shot find something else that works.

Why would you have to machine anything to make them seal?? I always thought that the whole reason for going to the cast manifolds was to get a reliable seal. I've been looking to uprade in this area too (still stock). I love those from allstar. I wonder if they would fit a burb

I don't think you have to, but have read a couple posts where guys have had them true'd up. Can't hurt and they are already going to be in the shop.

 

[chalet2506]

There it is. Couldn't find it online, had to get the part# out of my catalog at the house.

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=156

 

[bp71k5]

Oh yea! Post up on how they fit with the bigger manifold. I may have to pick up a set.


-Brian

 

[chalet2506]

Received my order today. Inside diameter of dump is 2 3/8", so I got the right ones. But, both have a heat tube so I guess driver side is what you need if you want to avoid those. No big deal, maybe I can even reuse the stock heat shield heat riser thingamajig.