I am interested in transforming a 390cid ford into a 431cid. A couple of the guys at the shop have said it should work really well if I take a 428 crank and rods and hook em up. Sounds like it will work well, but I need some more ideas from y'all before I go tearing into this project.
I like the idea of having the big torque numbers of the 428, but don't want to have to change the bell housing and mounts and all that in the 4x4 truck it's going into. I need more input. Will it work or not. Any other suggestions?
390-428 are both FE series engines if a 390 fits a 428 drops right in with no changes,sitting on the floor you couldn't tell them apart.429-460 are totally different engines and mounts and trans. would have to be changed.
All you should need is a 428 crank, 410 pistons and either flywheel/flexplate and balancer off a 410/428 as these two engines are externally balanced. The 390 rods should work fine unless you want to upgrade to a SCJ rod.
These guys are great and are and have been into FE's since they first became available. The FE's all use the same length rods except for the 352 which used a slightly longer rod. All of the differences in stroke for all of the FE's (330/332/352/360/361/390/391/406/410/428/427) are taken care of with different compression height pistons. The 428 has a standard bore of 4.130" which is .080 overbore for a standard 4.050" 390. Another thing to consider is what you hope to do with you're FE.
The 390 has a stroke of 3.78 and the 410/428 has a stroke of 3.98. There are a boat load of different opinions on overboring the 390, and I'll try to briefly touch on this and try to be "Politically Correct" when I say that you can safely bore a 390 .030 with very little concern and very little if any side effects. However, to overbore a 390 .060 or .080 will tend to prove that the engine will run a little hotter than .030 or standard bore. How much hotter depends on many variables and I'll just leave it at that.
All of this Hot Rod and/or Engine Building stuff comes down to "Opinions" and what has or has not worked for someone. So, I'm just passing on what my Opinion is, and saying that you should get more opinions from people you respect and then make your own decision on what will work for you.
[ December 23, 2002: Message edited by: BAFord427 ]</p>