Thinking of putting cats on my 67 Coupe...

[Loup-garou]

(snip)I'm going to tune it as best we can and then dynamat everything and put visqueen on top of that. If it doesn't work I'll sell.

Dynamat is neat stuff, but it's not a substitute for seam sealer (the car would still be smelly, but with remarkably little road noise!). I'd hesitate to put plastic sheeting down under the carpet, though - if any moisture gets under that stuff it'll never dry.

One area you might put the visquene, at least as a test, is under the rear package shelf and behind the back of the rear seat. If the problem seems to lessen, you know the fumes are migrating in from the trunk area.

 

[Loup-garou]

(snip) One of my racing buddies is coming over this weekend to help me tune it. If that doesn't work I am going to buy a 500cfm edelbrock or an autolite 480. I still can't believe that 600 is too much for my setup since the 84-85 Mustang Gts came with 600 Holleys I think.

Let us know how the carb tuning goes. Try to notice what jet sizes you end up using; I'm down here in the New Orleans area - and the "elevation above sea level" carb tuning chart does not have any negative numbers on it!

You're correct - the '84/'85 GT did come with a Holley carb - with the idle circuit needles recessed under steel plugs in the casting. Ford also used metering block and bowl gaskets that were inpregnated with some sort of adhesive - they *really* didn't want anyone to pull those carbs apart.

Generally, 600 cfm is not too big for a 302. It's more likely the jetting and such that's causing your problem, not "too much carburetor".