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Need help building a 400 big Block

Muscle Motors used to sell a 451 kit that was hard to beat. They may not even be in business anymore. I have a clean 400 that's torn down with the thoughts of a 451 but I got side tracked. I also have a 361 with a spun bearing, my fault.
 
Good to know , But I think he's got almost everything to do the build . It'll take a lil time for the 451 though because he's in the middle of getting the engine in his 79 Dakota small block drag truck .
 
Honestly, what stopped me was the extra cost. I had a running 400 and wasn't looking to shave a 1/10 of my ETs. so I just kept it simple. Any more pics of the truck in your avitar? It's very nice.
 
wedgeheaded said:
Muscle Motors used to sell a 451 kit that was hard to beat. They may not even be in business anymore. I have a clean 400 that's torn down with the thoughts of a 451 but I got side tracked. I also have a 361 with a spun bearing, my fault.
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I believe they are still in business. They can make you whatever you want.
 
I saw carb sizes being thrown around a little so I thought I'd add my 2 cents. I used the different carb calculators and first tried an 870 Avenger, worked very well but I really wasn't digging the vacuum secondaries especially with a standard. Next was a 850 Demon mechanical secondary, it worked well except I could never get the off idle right (needed adjustable air bleeds). I then made the decision to order a custom setup Quickfuel Q series 750 mechanical secondary and wow is it a dream to drive now. The bigger the carb the less velosity you have which weakens the signal resulting in a more temperamental carb which is where having adjustable air bleeds comes in.

With the new carb the biggest difference I noticed is it's crisp everywhere throughout the rpm range with absolutely no hesitation or bogging. Idle and just off idle performance is dramatically improved as well which makes a huge difference in city driving. Guess what I'm getting at is favor the small side on carberation if it's a street toy.
 
An engine is a big air pump with no reason to put a larger cfm carb on than the pump will pump. Matched air cleaners are great also. All the carb in the world will do no good if the air dose not flow.
 
So I took the 400 apart and there is slug from hell in it. It looks like someone put thick chocolate sauce everywhere. So I'm going to do a total rebuild and just keep my 318 in the truck for now till i can save up the money to do it right. I'm also scoring a rebuilt 360 for helping out a friend to put a 318 in his ramcharger. So I will have that but will probably throw it in my 68 valiant.
 
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