Its time for a new intake valley pan on my 1971 455 as the old one is leaking at the front.

I search up the Fel Pro and see two part numbers listed for the 455.
MS96004
MS96015
General description and pictures show the same. Available from many vendors.
Price difference of about 7-10 bucks, depending on supplier.

Please remind me and tell me what the difference is?

BTW I changed the intake gaskets about 12 years ago with the MR Gaskets 404's? and have used a torker intake with valley pan or fiber gaskets, for about 22 years.

This time, I'm going back to the factory cast intake. Cheers.

 

Don, not sure of the diff. It may be the heat riser hole? If it helps at all I use
the Fel Pro MS 96004 and toss the rubber ends and use RTV black silicone.

 

Both listed for the 45 engine. What I see in the pictures:

MS96004 - no oil drainback hole
MS96015 - oil drainback hole in middle of pan

 

^^^THIS!

The difference is the size of the heat crossover hole in the gasket. The 1973-up heads have a larger crossover port and the gasket is sized to match. Use the gasket that matches the year of your heads.