What would be the advantage of swapping a 351 for 390 . I found a great deal on a motor and trans combo. Just wondering if it would be worth changing the motor while I do the trans. I was planning on building the 351 but if I could get some nice power gains from the mild built 390 I would consider it.

Thanks,Martin

 

It's more expensive to build the 390, but that FE will run ALL OVER the 351. It will also be more durable than the 351. I'm going out of my way to swap in an FE in my '79, if that's any indication.

 

It would be a better motor for the constant need of torque in a 4x4 or offroad truck such as yours. The high nodular iron would take a more severe beating before one has to worry, and if you care mpg's if the 390 is sensible would be the same if not better.

 

Torque....

 

Will I need to change anything or will it be drop in and go cause I just bought it. This was just one of those deals I couldn't pass up and more torque is exactly what I want to spin these 40s. What are some trouble areas if any that I should address before putting it in. Also what must have mods should i do cause I've seen a lot of people running them lately and seem to love them.

 

Aluminum intake, quality set of headers , new style distributor cap and wires .
I personally prefer a holley carburetor and duraspark ignition.

 

So the usual stuff. I to am a fan of Holley carbs I was thinking about trying the off road avenger have you had one before?

 

big ol 2x on the headers they are worth every penny on these motors the factory exhaust manifolds are the worst possibly ever made..... the holley truck avenger works great on these 390's..... but make sure its a 390 check the stroke using a small dowel rod 3.5" is 360...... 3.73" is 390..... as all real FE fans know a 360 magically becomes a 390 on sale day.... if you check it out and its a 360 and you can prove it you can get it cheaper 90% of the time

 

Here is a thread that should interest you if the link works for me.
A stock FE is a restricted air pump. Open up the intake and exhaust
and ya will think ya got a new race engine.

I like the 360 fe do you?

 

Just picked up the "390" along with a second block and my c6. As my luck usually goes the motor I went to pick up was nothing like the pics emailed or described. The complete motor I'm almost sure is a 351 an a almost naked block I'm not so sure about. after chewing the guy out for 30 minutes about his bs he threw in the motor and block with my trans. If it truly is a 390 how could I tell since 352 360 and 390 all have the same casting numbers,just buy one piston and connecting rod for each motor and test for clearance. Cause after learning about them I want one!!

Thank you finally someone who's run a truck avenger. Is it truly an off road bashing high incline non flooding beast it claims to be?

 

have literally been in a truck almost completely on its side on the trail (purple bronco) never had an issue couldn't believe it was running as good as it was its a 750 truck avenger on a 4bbl 351 cleveland and also have one on a 390 in a truck similar to the 79 in pic that we have stood it on its nose both back tires off of the ground and left it idling until we got another truck hooked up to it to pull back out of the monster hole

 

Nice I'm defiantly getting one now I've been looking for that last awesome part to throw on the spending list. was yours good to go out of box or did you have to tweak it?

 

390's was perfect the 351c ran a little rich but we tweaked it to perfection but then again a 351c is more of an rpm motor not an idler.....

 

Hell yea I can't wait to get mine now. And hit the hills and test it out in some step inclines.