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is this a good deal for a 400?

hell im not sure what to do. scott is a professional and you guys have all been telling me you've had good luck with your 400s. i dunno what to do or build. i just don't want to get on that overheats or cracks the block cause that would be my luck
 
Well if you want a realiable stump puller than just do a stock build on a 400 sbc. You wont have any problems. Dont you think if 400 sbc were that bad gm wouldnt have made so many of them!! A stock 400 block with good heads and intake & cam (RV towing cam) will run awesome! Do a nice free flowing exhaust. If you want more power down the road you can always bore it 30 over.
 
well i got the eddy intake and carb and accel hei distributor from my 305 and i supposedly have corvette heads too. my plan was to pull these parts off my 305 and put them towards my 400 build up. start with a 400 2 bolt block, deck it, align hone it, magnaflux the crank and rods, shot peen the rods, balance the rotating assembly together, shave the heads, 5 angle valve job on the heads, stock crank, rods, speed pro pistons and piston rings, melling hv oil pump, stock pickup and pan, 2 piece timing cover, stock balancer, stock front drive system, comp cams 4x4 cam kit, flowtech afterburner headers, manley pushrods, comp cams pro magnum roller rockers (don't know what ratio), manley valves, manley valve springs or crane cams beehive valve springs, clevite 77 bearings, arp hex head black oxide fasteners, felpro or cometic gaskets, paint it and put glyptal in the lifter valley and wherever else its supposed to go, undecided on valve covers and other dress up items
 
If your gonna rebuild it, put in 5.7" rods. Stock style is all you need, don't need fancy H beams I beams whatever. Probly get a set of for free if you look around. Just have them resized and ARP studs. The pistons don't cost toom much more, and it's worth it the first time you drive it.
 
slyguy_22 said:
If you want more power down the road you can always bore it 30 over.
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Yep, it's definitely worth it to tear down a good engine and pay a machine ship to get that extra 6 cubic inches.......I mean, that's an increase of a whopping 1.5% !

Seriously, I have to shake my head everytime I see a comment like this, and I see it a lot. The only true purpose of an .030" overbore is to clean up worn out blocks, not to increase power. You are simply not increasing displacement enough to make any appreciable changes in power.
 
It sounds like you are pretty serious about making a strong engine, and based on some of your parts choices, aren't afraid to spend the money to make it nice.

I'd seriously consider some better heads in your case, new heads put old ones to shame, corvette or not, and next to headers are probably the biggest bang for buck improvement you can make. Depending on the engine likely even larger single improvement numbers over the exhuast, but the cost is a lot higher for the gains.

Besides, better heads will only make the headers that much more power producing, and vice versa.
 
theres a slight power increase but for the most part it is just to clean up the cylinder walls. now if you went 0.60 that would be more of a performance minded over bore
 
4X4HIGH said:
I simply stated that 400's like to run hot and they are notorious for cracking. I can't count how many i've had in my shop that were cracked through the lifter valley.
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38377k5 said:
400's have "siamesed" cylinders which means that there are no coolant passages between the cylinders which causes their coolant problems. I've also heard that 4 bolt 400's are notorious for cracking main bearing caps.

I chose a 383 because you get the longer stroke of the 400 but you keep the much better 350 block.
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Mine doesn't seem to be notorious for anything except running good since 1977. :dunno:
 
To say that 30 over isnt a big difference. it does make a difference. heck just changing the dome on a piston makes a huge diff. granted boring a block 30 over dosnt change much, but when you do that generally you are gona change alot more than just piston & rings. its all in what parts you use. so yeah 30 over can be no big deal or it can be a 100hp diff.
 
i have never seen a 400 sbc w/ only 2 ''freeze plugs''...the freeze plug...isn't a freeze plug....the holes that every1 calls ''freezeplugs'' are the holes that gm uses to get the sand out of the motor after it is cast, and i've been told the middle plug was placed there to allow the sand out of the mold b/c the siamesesed cylinders wouldn't let the sand out w/o the middle plug, and that all 400's have 3 plugs on each side.

and i have 1/2 dozen 350 blocks in my shop...part # 3970010, they all have the dipstick that presses into the block deck, none go into the oilpan!?!.

also on 400 sbc, you can feel down the side of the block and you can feel the radius of the cylinders, where as other sbc's the side of the block is flat.
 
blazin_blazer said:
i have never seen a 400 sbc w/ only 2 ''freeze plugs''...the freeze plug...isn't a freeze plug....the holes that every1 calls ''freezeplugs'' are the holes that gm uses to get the sand out of the motor after it is cast, and i've been told the middle plug was placed there to allow the sand out of the mold b/c the siamesesed cylinders wouldn't let the sand out w/o the middle plug, and that all 400's have 3 plugs on each side.

and i have 1/2 dozen 350 blocks in my shop...part # 3970010, they all have the dipstick that presses into the block deck, none go into the oilpan!?!.

also on 400 sbc, you can feel down the side of the block and you can feel the radius of the cylinders, where as other sbc's the side of the block is flat.
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SBC 400's had either 2 or 3 freeze plugs on each side. I've personally seen both.

Also you are correct that "freeze plugs" isn't the proper term but it is what is widely known and used. Other people call them "expansion plugs" or "welch plugs".
 
I have 3 400s, one that I know is a 4 bolt, has 3 plugs. Another one can't remember, but think that has 3 too, need to check. The last should have only 2 as it's a 79, 4 bolts went to 73....
 
i was just wondering what vehicle it was in. you got a good point slyguy 22, if you do a 0.30 bore unless its just for a freshin up your most likely going to add more horsepower with other parts combinations. oh and the other day i ran into a guy that says he has a 383 he wants to sell for $700. not a 383 stroker, just a 383. sounds too good to be true to me. he says it runs and all it needs is a power steering pump or powers steering pump bracket.
 
A 383 is a stroker or it's a Slopar motor. 350 block, 400 crank, 30 over. Might not be a bad deal, but I would be weary of buying a "built" motor off someone I didn't know.
 
a built 383 in my 56 plymouth would make it do about 12's and thats in a 3500 3600 car... maybe even heavier. mopars deffinately ain't slow
 
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