I am trying to decide what size headers to put on my 496 that im building for my 68 ss.The heads are the 074 aluminum gm heads.The heads have had a slight port match on the exhaust.the ports measure 2" the porting doesn't go down into the port they just kind of rounded the outer edge.I had thought about going with the dynomax coated headers because of the price and they look like they would fit nice and clear my stock upper control arms that have been moved in quite a bit because of my tall spindle conversion.But I think they are only 1 7/8" headers and I dont know if they will seal up to the heads.Also will they be big enouf for the 496?I could go with a set of hooker super comp 2" headers but some people say they don't fit real well and I am afraid they wont clear my upper control arms.Has anyone used used the 2' hooker headers and how did they fit?Would the dynomax headers seal up to my heads or are they too small?I might add that this is a street car that will have about 10 to 1 comp and a hydraulic cam with a max rpm of about 6000 so I don't think I need to get real crazy with tube size.Thanks Bill.

I am using 1.75" headers on my 505 w/049 oval ports for the time being, the exhaust ports were opened up considerably but the headers still cover the ports. I've made but one pass so far,with more to come tomorrow, hoping to get a 10.99 the way it is. I imagine 1 7/8" or 2" might be a better deal. I've run 2" Hookers on my car before and the collectors hang down really low.

my engine builder said I'd be hurting the potential of my 496 with anything smaller than 2" primaries...

I am using Hooker Comps #2455, which are 2" primary. No outstanding fittment issues, outside of the expected clearancing of #5 for the steering shaft (which is closer to the engine on '67 and earlier Chevelles vs your '68).

Thomas

See if you can find a header that doesn't overlap the ex port.

Does anyone have a set of 2" primary hooker super comps on a 68 up chevelle with a bb and how do they fit?

I run the 2" hookers on my 70 without any problems didnt have to touch any of the tubes very close to the frame rail on the pass side but clears everything fine.

Thanks!