I am thinking to stay near stock with intake manifold for my '68 XR7 X-code with the tweak of changing up to partial S-code by substituting a stock Ford 4V intake manifold onto it and Motorcraft carb. I know compression ratio and other rotating specs fall short of S-code and I know that aftermarket parts would outperform stock - just exploring the idea.
Question is - is there any mechanical fit problem that would prevent a '67 or '69 4V FE manifold from being usable if that was all I could find?
Thank you. Good information. Do you know if a manifold numbered as cast 66, 67 or 69 would fit a 68 block and heads? I am guessing that the dimensions would not be very different, but that is just a hopeful guess.
Hi Royce, hold on - I just found a previous post from you about 1969 390IP from a few years back - so were FE block and/or heads re-dimensioned for 390IP in '69 so that only a '67 or '68 intake would fit an early '68 late '67 engine like mine?
I do need to to go look again at the build date on my block, but my Marti shows my car bucked in February '68.
There are no revised FE dimensions. Any year 4V intake will fit any year FE so long as the style of engine - in this case low performance - is the same.
Do the homework on these FE heads,
there are low riser, medium riser, and hi riser heads with different compatibilities with different components.
Find out for sure what you have and add your upgrades appropriately .
The 427 came in various models like Low Riser / High Riser / Medium Riser and Tunnel Port. The 390 never did.
The only thing to beware of on a 390 is you do not want to use a cast iron or aluminum intake from an early T-Bird. Those are simple to spot because the carb pad is machined parallel with the sides of the intake. All other 390 intakes - the kind you want - have the carb pad angled because in all other cars the 390 sits at an angle.