400's are they any good?

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I'm not sure why you would need to go to 8000 rpm's?

here's my 400 based engine.
Shift around the 6800 rpm range.
Car runs 9.50's

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They can handle HP in the 800 range.
 
66plyValiant said:
I have the chance to get a 400 BB and a matching 727 transmission from a 70' s chrysler newport for free from a guys parts car, only thing I have to do is get his car he is fixing up running for him and he will give it to me. Are these 400's any good or are they boat anchors? are they a B block or RB? I'm looking to put it into a 77 dodge 1/2 ton. sorry for all the questions I'm more familuar with the 440's and 383's
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+1 :thumrigh: for the 400.

It may be a low compression, smog era motor, but WORTH putting money into to make it a high compression, high HP 451.

Plus it's free? Why the heck not?
 
Needsaresto; With using old 383 small chamber heads I was really talking about ways to take a stock 400 short block and try to build a dirt cheap motor that makes modest power. Its part of the debate about getting good power without getting a stroker kit and having all the machine work on the block. 25 years ago when I had very little money I did things like this all the time and street raced the hell out of junky combinations. One thing is for sure, trying to make good power with sub 9 to 1 comp and 400 or less cubes is not easy without power adders. You can't just throw in a big cam and expect it to work. I have no plans of throwing together any junk motors now so the post was only meant to be helpful to anyone who is doing this sort of thing.
 
Good engines, but not all of the 400 are the strongest out there, just certain cast numbers only the rest are as good as any 383 or 440
 
womanator said:
I'm not sure why you would need to go to 8000 rpm's?

here's my 400 based engine.
Shift around the 6800 rpm range.
Car runs 9.50's


They can handle HP in the 800 range.
Click to expand...

400 Based? Is i a 400 or not? Not really helpfulto the guy looking to keep it a 400, but note worthy non the less.

Doosterfy said:
Needsaresto; With using old 383 small chamber heads I was really talking about ways to take a stock 400 short block and try to build a dirt cheap motor that makes modest power. Its part of the debate about getting good power without getting a stroker kit and having all the machine work on the block. 25 years ago when I had very little money I did things like this all the time and street raced the hell out of junky combinations. One thing is for sure, trying to make good power with sub 9 to 1 comp and 400 or less cubes is not easy without power adders. You can't just throw in a big cam and expect it to work. I have no plans of throwing together any junk motors now so the post was only meant to be helpful to anyone who is doing this sort of thing.
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On the cheap is a great thing to look into. It really helps those of us that have shalllow pockets but a great yearning to do something rather than sulk, moan and wish apon stars. Nevermind stroking it!

Everyone is so quick to scream stroke it or dump it in favor of a bigger engine. Such a shame.
 
How fast are you looking to go? I have a 400 in my garage and not sure if I will use it or not. Still looking at 440s for the "Joe Dirt" Coronet.
 
Doosterfy;yep I agree,not a lot of power to be had from a stock lo comp 400 without a turbo or nos etc. I guess throwing 383 heads with small chambers would help comp some allright,but how much work do they need to make some good h.p? Bigger valves,port work? Probably not that cheap of a solution.

Demon 1515,all 400 blocks are stronger in the main web than anything else mopar produced.It's in the design. A 440 block is good for about 600 h.p,but they werent designed to withstand the power that modern heads can produce.

The B1 head was designed with the 400 block in mind,before the aftermarket block was available because it could withstand much more due to the heavy duty main web design.

Who knows why mopars engineers saw fit to put such a heavy duty main web in a smog motor,but god bless em!

No other block can offer as large of a bore either,which helps air flow so it has that edge as well.

The thin wall block rumour is a myth as well. You could go and sonic scan any 400 block and it wont be that bad. Not many of them were so badly core shifted as to need sleeving.Probably no better or worse than any other block in that respect.

Go and ask any decent engine builder that knows mopar and they will tell you to build a 400 block up if you want to make better than 650 h.p without buyinf an aftermarket block. If they want to use a 440 block,run away.
 
demon1515 said:
Good engines, but not all of the 400 are the strongest out there, just certain cast numbers only the rest are as good as any 383 or 440
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400 blocks are much stronger than 440's and especially 383's. I love the 383 (got one I'm driving now) but for sheer strength it can't hold a candle to the 400 block, any 400 block!
 
needsaresto said:
The thin wall block rumour is a myth as well. You could go and sonic scan any 400 block and it wont be that bad. Not many of them were so badly core shifted as to need sleeving.Probably no better or worse than any other block in that respect.

Go and ask any decent engine builder that knows mopar and they will tell you to build a 400 block up if you want to make better than 650 h.p without buyinf an aftermarket block. If they want to use a 440 block,run away.
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x2!
 
If you go through all the money and trouble with machining for cross bolt mains, girdle, etc, economically you'll be at the same price for buying a new aftermarket block. Initially I was going to go the route you are talking about, but after I added it all up, I bagged the idea and ended up buying a brand new 6.1 Hemi for $4300.

Buy the book 'How to Build High Performance Big Block Mopars' by Andy Finkbeiner and you will learn a lot about these engines. The book is very good.

I know there are other schools of thought out there, this is my perspective. Good luck in whatever you decide.
 
found out the 400 is stuck pretty bad from sitting:sad7: I think I may buy a local 440 for $150, was rebuilt and put into a boat, boat owner found out car engine spins wrong way for boat and removed it:toothy7:
 
demon1515 said:
Good engines, but not all of the 400 are the strongest out there, just certain cast numbers only the rest are as good as any 383 or 440
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That's horse feathers. There won't be 100 HP worth of strength between a "good" number block and a "bad" number block. There's no real evidence to support it either way, really. Just a bunch of bench racin BS. I know somebody that runs a stock stroke 400 in a 10 sec gasser Gremlin and a 451 in a strip only 10 sec Dart. Neither of them is the purported "good" block and they've both been together for over 5 seasons. "Only" as good as the 383 or 440? Oh gawd, I guess now we gotta throw all those away. ....rolls eyes......
 
i actually have the steel mounts that came out of my dodge 72 dodge truck think they were all the same for those years not sure though let me know if u need them
 
I dont like the Procharger idea... It's cheap, but takes a ton of power to run and puts a lot of stress on the nose of the crank when you start adding boost. If you are building for 1000hp, then buy a real (aftermarket) block. If it's more a question of I want a solid BB B wedge in my car, build a 470 N/A and get a top end that will make some power. Bigger cubes than that and you get into some very short pistons, and again, you start losing power from ring sealing issues and you lose longevity. You have a base 400. If you want a modern build, use aluminum closed chamber heads, build for quench and dynamic compression. Have top quality machining done. I dont think 8K rpm is needed or realistic, but some people just want to be able to. In order to do that regularly, you'll have to do some oil system work and run a light crank and really good light rods. If you want to buck the system, stick a turbo on it, leave it at 400 cubes, and you can make an easy 1000hp fairly reliably. Until the main webbing fails... which is why I say use a better block from the get-go if that's your goal.
 
Yep, I can see that trying for really big power from a stock block is a bad idea. I never really thought about how much stress a centrifical blower puts on the crank snout, but most of the centrificals use a factory ribbed serpentine style belt (at least with low boost). The 6-71, 8-71 roots blowers definately put a hurt on the crank. A friend of mine broke the snout off of his freshly built small Chevy the first time he romped on it and ended up having to go with a crank with a big block sized snout. I have no plans to do anything with my 400 any time soon, its now safely stored in my garage and I'm getting ready to finish up my 440, as the short block is complete and ready for heads. As far as turbos are concerned, I'm not not using them. I've had a turbo Shadow and a LeBaron and I used to build alot of parts like intercoolers and intake pipes and exuast parts for a bunch of the front drive Mopar guys so I've had my fill of them. The problem with them (to me) is that they turn into one big science project and the boost greed always takes over, as in "wow 10 lbs is awsome, lets try 15, even better, how bout 20, holy s$#%!", then comes the broken motor.
 
Anyone have any ideas for one going into a 68 B-Barge Coronet 2 door? The car has a tired mild built 68 318 (cam, headers, intake, 4bbl) with 2.76 gears. I have been told it could be turd even with headers, intake, Firecore ignition system and convertor? I am hoping I can get some 3.23s in the rear for free but, we'll see. I already have a supposedly running '74 400 and 727 I bought for somewhat cheap . Been looking for a decent late model 440 from a car or truck locally and can't seem to find one cheap enough so it's looking like this engine will have to suffice.
 
magnumminded said:
Anyone have any ideas for one going into a 68 B-Barge Coronet 2 door? The car has a tired mild built 68 318 (cam, headers, intake, 4bbl) with 2.76 gears. I have been told it could be turd even with headers, intake, Firecore ignition system and convertor? I am hoping I can get some 3.23s in the rear for free but, we'll see. I already have a supposedly running '74 400 and 727 I bought for somewhat cheap . Been looking for a decent late model 440 from a car or truck locally and can't seem to find one cheap enough so it's looking like this engine will have to suffice.
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I been tinkering my 400 more and more lately and am pleased with it. I have an older Hughes cam in it (470 lift, 214 dur and 108 LSA), Edelbrock Performer 383, rejetted 600 Holley (works good but a 750 would be better), exhaust manifolds with 2.5 inch dual exhaust, double roller timing set, high volume oil pump and 452 heads. The 1 inch spacer under the carb really surprised me.

It it a respectable performer in my ' 65 Newport coupe which is heavy to say the least. It' gets decent mpg(for what it is) and rolls strong up the interstate with the 2.76 gears. Provides plenty of passing power when needed and has a nice little lope to it. Fully streetable power...

This thing in an A body would be crazy fun and I bet a B body would run real good as well. I like the 400 and see the potential within...

Please give me all your worthless 400's, I will give them a home here!
 
I ran the piss out of my 451 for 2 yrs. & it never missed a lick & was the quickest BB i built, A buddy of mine ran 9.3s with his 451 Dart, He took me for a ride in it & literally scared the "sh*t" out of me on the back streets, He was running over 650 HP & a "stock" block.
 
Thanks guys that makes feel better. Even though the car is an R/T clone I don't think anyone would really notice too much.
 
Just thought I'd throw my 2 cents in.

The 400 has very strong main webbing and the largest bore offered by Chrysler. I have one that will be dropped in my Duster but it's on the back burner right now since I restored my motorcycle, but I'll starting a thread on it in the next month or so.

The plan includes a forged Callies stroker crank, CR will be in the 10.5:1 range. Solid roller cam in the high 250's for duration and lift in the .600 range. Ported eddy victor heads, dual quad intake, biggest tube headers I can find, milodon oil pump and some other stuff TBD. I spoke with my machinist and he feels that 600-650 hp @ 6200-6500 is very doable with this combo at the 6000' altitude of Bandimere Raceway here in Colorado and may well be conservative. He says tens easy on slicks once the chassis and engine are tuned. The work he and his crew have done for me has always been top notch and he's been a machinist before I had drivers license, and I'm going to be 46 here pretty soon.

It will be on the ragged edge of streetability, but it's mostly for the occasional weekend drive and the strip.
 
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