pro's and cons please mopar content

a guy has a 400 bb chrysler 1974 out of ? . i need the pro and cons . good or bad . i always seem to find the basterd of projects is this one ? not asking rebuilding advice or how to tell if its junk just the good and bad about the bb 400. thanks rick

 

They were the junk of the 70s, poor compression, retarded cam, 2 bbl.
Then the racer guys figured out how to stuff a 440 crank into them.
It's a good start if you want to spend a bit and build it up, but they still aren't worth much as a core.
Do a search for Mopar 451.
You can get crazy and go as big as 500 cubic inches, but the ring packaging is not for a street car and high miles.

 

I'll take the opposing view. My 73 RoadRunner came from the factory with 400, 4-bbl, 4-spd, and it runs as hard as any 68-69 383 RR. The basic package will be low on compression but that is about all. Look at the factory service manuals for the 74-400 and compare to the 68-71 383. You might be surprised at how little was changed, and don't fixate on the HP numbers...the whole rating system changed in 72 to keep the output numbers down in order to keep the insurance companies happy.

And yes, you can put a 440 crank in with very little effort and you get a 444. Keith Black has pistons on the shelf for use with either 400 or 440 rods on the 440 crank.

.

 

+1more for the mopar usage! find a local mopar racer and ask around for who's building them in your area. There are reasons why Mopar mills were competitive with smaller cubes.

 

Go t 440source.com lots of info

 

I have never messed with a 400, but when i was building a 360, the guy who did my machine work kept urging me to ditch the 360 and build a 400 instead.

 

typical 70's cast crank BB chrysler. slugs are .115 in the whole. 452 heads have nice large chambers,and flow great,but don't help the 7.9-8.2 to 1 compression. cheap and easy fix is a set of 66-67 346 or 516 heads from a 2 or 4 barrel 383. these have smaller valves and chambers than 906-452's,but with .039 fel-pro headgaskets,will bring that 400 to 9.2-9.5 to 1 compression. add a nice cam (472 or 484 purple stripe mopars work well,personnel preference is comp cams XE-268) edelbrock performer/performer rpm,600-750 carb (cfm more dependent on cam choice) cheap flow-tech or equivelant headers,and good ignition(mopar performance electronic conversion kit with performance distributor/and orange box) together will easily yield a 300-350 hp motor and well over 400 lb.ft. of torque with excellent street and temperature manners.

 

If I had the chance and the engine bay room, I'd do a 451 motor (440 crank in a 400) in a heartbeat. With a decent cam and carb, 350-400 HP and almost 500 ft/lbs of torque.

I've been looking for a 400 block for a while, none to be found in my (very low) price range nearby, and anyway it's for the next project and not something I need right now.

 

1 more for 440source.com

 

short deck mopars are good motors.. 383's / 400's can pump out some serious hp. low compression can be cleared up with a .010 mill job on 452 heads (just make sure to make some shims for the rocker arms or shorter pushrods) with a good purple cam one can expect 1hp / ci other benefits are the skirted bottom end for great bottom end strength. and really beefy hit it with a 100hp nitrous shot and your at the 500hp mark.

 

2nd that 440source.com most cost effective.

 

I totally disagree. 400s are EXCELLENT motors to build and not nearly as expensive as some of the other motors people seem to put on a pedestal around here. 400s are actually quite desireable due to a supposedly stronger bottom end webbing in the block. Not sure quite how true that is. They are low deck motors, so they share the 3.38" stroke with the 350, 361 and 383 B, however, they have a HUGE bore and with the stroker kit from Muscle Motors (I believe a 4.25" stroke), will go to just over 500 cubic inches. Though the 400s share the same stroke as the other low deck big blocks, many of the earlier cranks are not interchangable, as the earlier and stronger forged steel cranks have a smaller thrust bearing than the later cast cranks. Even still, the cast cranks are good for almost 500 hp.

The cheapo MoPar orange box electronic ignition conversion is powerful, reliable and relatively inexpensive, making your ignition issues virtually non-existent.

Intake swaps are a breeze as no water runs through the intake. Just pop the 8 bolts out and you can change your entire induction without disturbing your coolant system or pulling the distributor.

They weigh the same as a Y block Ford but have ~100 cubic inches more.

The 400 will benefit greatly from an increase in compression. Earlier heads can be swapped on, or there are plenty of aftermarket options that will make enough power to sterilize you. Even with low compression, you can make enough torque to turn the earth on its axis and lug around a 50's barge with highway gears like a diesel was under the hood.

They sound awesome

Shaft mounted rocker assemblies are sturdy, reliable and utterly fool-proof. If you run a more radical cam, you will need to opt for adjustable rockers, which can get pricey.

They are more expensive to build than a SBC or SBF. They are much less to build than a Hemi, Cadillac, Rocket Olds, Y block, Flathead, etc. They're prob on par with, or slightly less expensive than BBF or FE.

Anything you need is available in the aftermarket, your only limitation is your budget.

Cons are very few. They are a bit wide. Exhaust manifold studs are drilled through to the water jackets and often rust in place. The external oil pump has a tendency of getting in the way of things. Easy solutions to both of those problems though.

 

Damn nice information up there^^^

 

You are right on the money! a buddy had gone through a bunch of 383's, kept taking out the mains, finally figured out it was the block distorting at high rpm. they sleeved a 400 down to 383 bore and no more lost cranks! here is a pic of it.

 

I have built a few 400's for chevy stomping duty and here's what I have learned:

For a cheap street killer motor, take one low mile 400, take the glaze off the cylinders, put in some moly rings, new oil pump, good cam like the ones mentioned above (don't go crazy on the cam - you can't rev it very high which I will explain later), mill the heads .060 (shorter pushrods or adjustables or shimming the rocker shafts will be necessary) bowl port the heads and clean up the runners, gasket match the ports, bolt on some 1 3/4"x36-40" primary headers, a good single plane intake (edelbrock torker, weiand etc) and a 750 carb (carter comp series AFB always worked for me, but Holleys or Demons are good too) and go hunting. Milling the heads .060 will net about 9.25:1 compression and make a ton of torque with a moderate camshaft.

The pistons in a stock 400 are the heaviest motherfunkers ever used in a big block, and they are cast. This means keep the revs under 6000 and it will live. get up in the 6500 to 7000 range and the wrist pins will pull out the bottom of the pistons.

Going to the next level with light pistons will make the 400 a screamer but will require much better heads etc.

The cheap street combo is so much fun!

 

here's the link to the 440 source site about block thickness (I have posted this before)

http://440source.com/blockinfo.htm

 

The 400 is HARDLY a "junk engine" as posted by RodStRace; from his posting, I'm willing to bet he's had nothing to do with 400s to start with. They make fine street engines, as described above. The stroker treatment with the 440 crank makes these flat scream, for not much more than a SBC 383 build.

Build that 400!!!

 

My 400 is almost done, stroked and poked. 440 H-beam rods, 440 steel crank. It was a budget build, the engine was cheap, had the parts and some other odds and ends laying around. This will be an awesome street engine for my car, easily 550 ponies.

It will rev fast and it'll get you out of the hole, it's going to be an asphalt buckler.

Dashman's Hot Rod & Speed Parts

www.dashman.net

 

I said they were junk in STOCK form. Then I listed why. Then I said that they could be made into good engines and how.
I have a 451. I LOVE it. Revs like a small block, but with a deep roar that isn't some small cube wonder.

Some of the other motors of the 70s that were bad stock are the 400 M Ford and the 265 and 305 chevys. Same problems; low compression and small, retarded cams. I've seen people go through all the work to swap them in and not do a thing to them. What a waste.

There are now people looking for 400 engines to build, but you still don't usually pay the same or more than a 440. That means cores are less.
I may have been short but I stand by what I said. Hope this longer post explains it.

Here is a good explaination of all the reasons why it can be built into a great motor. 7.6 pounds!!!!!
http://www.arengineering.com/articles/451.html

 

That's what the engineers figured, the 17 extra cubes would offset the drop in compression, & the compression is easily cured when it gets rebuilt.

 

I ran a wicked 400 in my 64 Fury.That car was FAST!!

 

your funny i love brain wash people

 

Huh?

.

 

I am very happy with my Hughes cam!!! Love my 361 Chrysler w/ STR-15!!!

 

your right on joe vinny,s building one for the 58 plym conv.

 

http://seniordragster.bravehost.com/leman.html
Check out these video links.
This is a 400 BBmopar i built for road racing 5 years ago. It is still running. It has aso been snuck out on the street (Auto bahn ) for some heavy lunchtime test fun so i have be told. It is 9.6 to 1 compresssion hydraulic cam, ported 452 heads , Holley Str Dominator intake with a 800 DP. It works very well. I have also built a cheaper drag version (aka The 400 Cheapie ) for a friend here . It ran 11.55 off the trailer on its first pass and yet is a streetable engine . It was in a 82 Mirada race car. I built the 400 cheapie first . That is when my attitude to 400s changed.
The 400 mopar has the largest bore of all mopar blocks and yet has a stroke shorter , A HUNDRED THOUSANDTHS shorter, than a 350 chev!! It will not hurt itself. The euro engine produced 408 rear wheel hp which is not more than 510 Hp and not less than 485 using accepted best case /worst case formulas for drivetrain loss or absorbtion. When i built these i had to make or have custom made pistons (I did one engne of each) . I ported the 452 castngs in house. Now you can buy pistons form KB and the 440 source heads or for a few bucks more the Eddys will do a better job that the best 452 906 or whatever iron heads for about the same money as you will spend freshening them. By the time you buy valves, valve springs ,retainers, keepers ,do the machine work even without the porting cost you will spend the same gold so why waste the time when either of those aluminum heads will flow more air and come ready to go. Straight out honest. Me to you. I was astounded at how well these engines perform once the compresson ratio is fixed . Having been a 440 man for years (even wrote the book on them)"Old Reliable") I did not expect the performance we got. The 400 Cheapie in the Mirada was just stop gap engine for my pal during some lean times. He would'nt take it out for several years though because it worked so good. (It cost under $2000 but we used a set of heads i had done for his old engine previously. ) After that when asked to supply the road race practice and driver traing engine for the Nascar returns to Lemans project it was no trouble picking the 400. That engine as you can imagine is a bit more exotic because it has to endure everything and for a long, hot, time. (It has too, for 5 years.) Both run the same hydraulic cam.
We have also built from 400s 460 cubes. (Chrylser Power Mag 1997 july or August issue i think. $1500 Econ Big Block) Later we built a 455 inch (055 over instead of 060 just because we could by forgings off the shelf that would work in our combo) Also we have running a 426 inch 400 based engine ,hand made pistons from accelatable forgings of like dimensions. This engine has stood some severe abuse (Air shifter malfunctions etc etc) and is still runnng after 4 or 5 years of hard racing. It is shifted a 6850 for max power but has seen 7800 on many occasions too. It makes around between 600 and 650 HP running 5.90s in the1/8th mile in a RED of old school match race weight and it did several years in the Mirada as well running consitantly 10.40s.
They are a very good engine. Better than most of us realize. (including Momma Mopar!)
Don

 

So, what family of engines is the 400? Can it be passed off as a smaller cube Mopar ? REALLY interesting thread on a little known/used engine?...

 

Hard to tell if there's a serious Q in there. The 400 was viewed as a lo po smog motor that replaced the well liked 383. Potential was ignored for decades. The engine looks like any other BB Chr., doesn't look like a SB, but you could put 361 or 383 decals on the air cleaner!

 

The 400 is the B or low deck motor. The RB is essentially the same motor, with a taller deck height and slightly wider intake to accommodate the extra width. The 400 looks virtually identical to the '58 350 and '59 361 motor. The only real difference is the 4 vs. 6 bolt valve covers. Even still, you could use 4 bolt covers on a later 6 bolt head because the middle 4 bolts are identical, just doesn't have the outside 2 bolts in the lower corners. Offy and Edelbrock both have finned valve covers for these motors. The 6 bolt covers do seal better though. There are also different casting marks on the later heads but someone would have to be a MoPar freak to know the difference off the top of his head. Find yourself a nice Offy or Weiand (say why-and) intake, and you'll be rolling like it's 1960.

 

Just so everyone understands even though there are lots of choices, the difference with a Holley Street Dominator intake is huge. I hunted North America to find the one for the lemans engine. Also excellant is the Eddy Performer RPM. Carb should be nearest availble at double the cubes. (400X2 =800)