400 build?

[A383Cuda]

I just came across a standard bore 400 short block for $50. The guy has had it around a while and says it has been sonic tested. The crank and caps all appear to look good. What kind of build up would you reccomend for a weekend cruise night car. I want impressive but dependable horsepower. Something I may even drive to Hot August Nights or Power Tour. I'd like to be capable of low 12's. Thanks!

[Killer_Mopar]

I would buy the block without a second thought for 50 bucks. Since you are buying a bare block with caps and a crank, make a stroker out of it. 440source has their kits on sell and they can even balance their kits now. I heard they went to a cheaper piston, but for the price they are extremely hard to beat. You can get into the low 12s with a 400 stroker if you build it correctly. I am close to done with my 451 build and according to the engine simulator I should be between 500-525 hp which should be good for low 12s depending on weight (hopefully I can verify this summer ). I wouldn't consider my build anything wild....just a 451 rotating assembly, ported and polished heads, hughes 2328 cam, 1.6 rockers, torker, 850 demon, headers, and dumps. You can go with a 499 stroker but I heard that with the short piston ring configuration they wear out pretty quickly,  this is what I "heard" so take it as that. Im assuming you have a 383 in your cuda right now and the nice thing about the 400 is that parts interchange with your 383, so you could reuse some of your stuff. Also, another good thing about the 400 is that it looks exactly the same as a 383, so you can tell everyone that it is a 383 and they would be none the wiser. On my car, I am leaving the 383 emblems and if someone races me and loses I can tell them they got beat by a "lil ol' 383"  and if they win I can say "I only have a lil' 383" In either event they will be scratching their heads.

[Kapteenikosmos]

with 512 cid kit from 440source the pistons would be bit higher and the rod to stroke ratio in acceptable levels. Only problem in that configuration is that the rod journals are in CHEBBY    size but I don't think that it can convert mopar into gm when rest of the parts in the car are authentic muscle power!

[nivvy]

451 StrOkEr all the way...

[moper]

Depending on what you have to use now, the 451 using 440Source's kit is a great way to get a nice engine. They are not as strong as the 4.15 or longer strokes, but they are smaller and lighter than an RB, and you can run them well on factory iron heads. I built one of these (short block) last year, and the cost at that time was about $3800 for a complete (unassembled) shortblock. Including oiling system, cam and lifters, covers, etc. So it's a decent deal. You could even reuse your 383's heads and intake. You can go bigger, but sometimes going bigger rpesents enough issues by itself that it just isnt feasible.

[A383Cuda]

Well, the Cuda was sold in December.  I am going to put this into a 1970 convertible Coronet R/T clone. I have been looking for a 440, but I am not really finding anything decent that isn't big bucks. I have a lead on a 78 Dodge 4X4 with a rebuilt 440 selling at $2500. I was thinking if I can get it for $2000 I'd do it. Came across the 400 short block, basically block crank and caps. It does have the piston rods in it, but pistons are probably junk. I had not really considered a 400 before, but with a $50 price tag, I feel it's worth jumping on. Would I be better off buying the truck with the 440? Truck is a project truck, don't want it...but would consider it to get the engine. If not, then I have a 400, no 383 parts...basically starting from scratch. I would tend to favor the durability over the higher HP. As I said it will be a weekend cruiser. No drag strip activity. Is the 451 the way to go? Does the 440 give me any more advantage? I know it's a rebuilt running engine. I'm beginning to think it might be the better deal.

[Killer_Mopar]

You know the 440 was rebuilt but do you know who rebuilt it and with what parts? If it was a reputable builder with decent parts then go with the 440. However, if you cant find out who built it and/or if it has cheap parts in it, then 2000 won't be such a great deal anymore. I would rather be engineless than to have a 2000 dollar ticking time bomb. If the 440 was rebuilt to 78 specs then it wont be much good to you anyway because it will have low compression and require a lot of work and money to make it run 12s. I have a lot of money tied up in my 451, but I know everything I have and what it was designed for. I guess what Im saying is that you will need to find out what parts are in that 440, who built it, and how long ago before anyone can say that it is a better way to go. Also, the 440 doesnt really have any advantages over the 451...they are basically the same rotating assembly (the extra 11 cubic inches comes from the bore). The 451 has the advantage of being smaller, a little lighter, a lighter rotating assembly, and 400 blocks are easier/cheaper to find.

[moper]

"better deal" is entirely dependant on what YOU think...lol. I dont have luck selling beater trucks, and they are not the easiest to get an engine out of...lol. Plus, as was said, rebuilt doesnt mean good, or good enough for your intended usage. 12s are easy to get with a low compression engine. I ran 12.40s with a ,78 440 longblock, a hydraulic cam, headers, and a 6bbl years ago. Drove the car daily for 3 years. The 451 is basically a shorter, lighter 440. There is almost no bonus other than those two to building one. So it's really your call.

[A383Cuda]

Points well taken. I tried to find out about the motor in the truck the kid told me his dad built it and was then diagnosed with cancer. He has since died. He had, the wife believes, $3500 into the rebuild. It had sat for 3 years and the son recently started it up. It runs very strong, he says. The dad used to be a manager at a local gas station, the kind of gas station where they also work on cars (some younger members may not know they actually existed). This leaves a question as to the quality of the rebuild. He rebuilt it himself. Did he use quality parts and actually have a higher $ amount in it than what he told his wife? (a likely scenario, plus he may have gotten parts at a discount). Did he try to build it on the cheap? I am going to go out and look at it this weekend. I will look for high quality accessories like msd box, aluminum heads, aftermarket intake, march pulleys, etc. and then make a decision.

[Chryco Psycho]

I would do the 400 with the 440 crank & rods from 440 source , the 451 is a good engine

[A383Cuda]

dang, chryco...you always have to come in and change my mind. 
I was actually thinking about this earlier this afternoon. There have been some great points brought up in this thread. The weight savings with virtually the same C.i. seems like a real deal all the way around.

[Chryco Psycho]

Opps
 I`ll shut up now

[KellysCuda aircard]

I would do the 400 with the 440 crank & rods from 440 source , the 451 is a good engine

I also would build one, I read in mopar action, that this combo is more durable, longer lasting  and will take revs better than a 440.

[moper]

For all intensive purposes, it IS a 400. RB 451 is a 440 bored .060 over (4.385x3.75)  B 451 is a 400 bored .030 over (4.380x3.75). Same rod length. What you get as bonuses are less total weight, easier packaging (unless it's E heads in an A body chassis...lol), stronger block in the main webbing area, and 383 looks. It will last longer under high abuse..Milage by normal wear and tear is the same as a 440.

[v8440]

Another thing you get with a 451 (and any lowdeck stroker) is a shorter, lighter piston.  This is a separate and distinct benefit from the engine simply weighing less, which it also does.  The rotating assembly will probably need to be balanced, but it won't be a difficult or expensive balance, since they should end up drilling metal out of the crankshaft instead of putting mallory metal in.  It'll rev a little quicker than an otherwise-identical 440 because of the lighter bobweight, too.