Holley and Borla 8 stack interference

Larry L.

Lifetime Supporter
A photo would be a big help here. 'Solution may be as simple as going to a distributor with a smaller diameter head (e.g.:MSD makes one) depending on how much and exactly where extra clearance is needed. :)
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Bill, post a pic and what engine used so we're all on the same page. If no solution with present setup and fuel pressure regulator location, you may have to switch to the narrow MSD distributor, or consider throttle body extensions? A pic will help...

Rick Merz

Lifetime Supporter
Flip the fuel rails, put the regulator on the opposite end (near collectors) or get a different distributor (assuming your fuel rails run down the center like mine).