Hello, I think this has been already covered a few times before but I would like to ask what modifications need to be done to switch from a Ford 351M/400 engine to an FE-390 big block.

Thanks.

 

IM looking for the same answers. Will 390 bolt to 351M perches? Yes/NO?

If I get Info I will pass it on to you.

 

I'm pretty sure I've read on here that you need to change the perches and it will bolt up.

 

Different perches, mounts, bellhousing pattern, etc. Pretty much everything is different. IMO (and I'm a fan of the FE) if you're going to swap anything in to a 351m/400 bay then you might as well go 460. It's much easier, L&L has everything you need for the swap.

From what I've read from people who have done these swaps is that if you are looking for 410-425hp or less it's cheaper to rebuild the 400. Past that, a swap to the 460 takes over the $/hp race.

An FE is great but it's not the most economical option. Your going to pay more to get the same power from an FE as a 460. It's just the way it is with the aftermarket support. The cheapest and easiest option is to rebuild the 400. For that I'd contact Tim Meyer.

 

Thanks for the info, personally I don't care for 460's too much and I strongly dislike the Cleveland engines, I've got FE stuff around in my garage to build lol. Thanks again for the info.

 

I know the feeling. It seems like everyone has a 460. Not as many FEs. It may be more expensive but, I like it. Well hopefully someone will chime in here thats done it. You might try a forum search and check out past threads of people doing the same swap. Best of luck.

 

Yeah, it seems like all the time I see people taking FE's out for 385 series engines, I don't get that. From what I've seen the FE's were more reliable and parts seem cheaper to buy from the 385 series.

 

I would like to see the frame perches that I need. I've read that the 300/6 will work but I think they are different in a 2WD vs. 4WD.

I'm going to try the 351/400 perches hopefully in a week or two. I'll let you know how it works out. There is much debate between this site and my machinist who says it will work fine. He is major Ford guy and always has been so we will see.

 

Thanks Sleepy for the help but I have a great running 390 FE & 250$ will get C6-FE to push my 78 LWB.