hello, im going to be looking at a 400 block this weekend, and im probably going to buy it.

it is a 509 block, can you guys give me all of the info related to this block, and what i should look for etc?

thanks a lot guys! hopefully i can have what i always wanted, a 400 build!

Check for cracks in the main webbings, any place that has any kind of crack in the cylinder bores, any place that looks like it has been welded on, look at the bottom end closely.

Check for cracks in the main webbings, any place that has any kind of crack in the cylinder bores, any place that looks like it has been welded on, look at the bottom end closely.

thanks, so is any crack in the block not acceptable?

it was mag tested, and came out ok

also what are all of the differences between these blocks and the 350 main blocks?

im seeing the stock bore is 4.125" and stroke is 3.75"

i see a lot of people with a 406ci.. are these the same blocks they use on the 410ci sprint circle track cars?

is the gm block capable of being a 427/454 or do you need a custom block?

edit* i also hear these engines have cooling issues, and they can heat up and crack, what is a way to prevent this, do i need anything special like a different rad/water pump, or what?

the cooling issues is a myth.
unless you dont have proper cooling any engine will overheat.
.030 over is a 406
.060 over is a 408
anything more is disaster.
427 smallblocks use taller decks.
cant do that with a 400 GM block

the cooling issues is a myth.
unless you dont have proper cooling any engine will overheat.
.030 over is a 406
.060 over is a 408
anything more is disaster.
427 smallblocks use taller decks.
cant do that with a 400 GM block

cool thanks, this is the type of info i like to hear

so basically a stock 69' camaro rad and a normal water pump will do fine?

im assuming the blocks use the same internal minus the crank? i see jegs has bearing spacers to let you use a 350 crank in a 400 block

how would a 215cc dart aluminum pro head work, to small or big intake runner?

this is what im looking to do to the block, thinking it will not need to be bored out:

http://www.dartheads.com/products/top-end-kits/sbc-top-end-kits/sbc-pro-1-top-end-kits.html

215cc intake runner with the single plane intake

im currently looking for rotating assemblies, and i only see 401ci, im assuming they are talking about a 400 block?

anyways, im trying to get around 12:1+ comp ratio and i want a comp cam 292h or s cam, i have not decided if i want to go solid or hydraulic yet

edit* actually is there any problem with using those 350 main adapters to use a 350 crank? (i would use a 383 crank) but im having a hard time finding a 300 crank thats not $900+

the cooling issues is a myth.
unless you dont have proper cooling any engine will overheat.
.030 over is a 406
.060 over is a 408
anything more is disaster.
427 smallblocks use taller decks.
cant do that with a 400 GM block

You may want recheck your math as a .060 over 400 is 4.185 and the cubic inch is 412 not 408

A .040 over 400 is 408 cubic inch.


When buying a 400 SBC for performance use you may want to sonic test it first and don't go by core shift as its very accurate when you have a sonic tester.

If you are going to build a 377 using a 350 crank in the 400 like you mention with your bearing spacer comment, do not use the Comp Cam or the Jegs spacers. They are simply made from 400 bearings. Get a set of King bearing spacers. They are made much stronger and are made specifically to be used as bearing spacers, not old 400 bearings machined to work as a spacer. You don't need the groove in a spacer like the Comp Cams and Jegs and others have. The best way to do this however is to pick up an aftermarket crank made for the 400 main bearings but with a 350 stroke. The Eagle 4340 blems can be had for $300. Eagle turns them 10/10 and sells them. The nitriding is .020 deep, so it's still hard.

I wouldn't go beyond a 412 (+.030 with 3.80 crank) in a stock block. It isn't worth it to go further for all the clearancing you'll need to check and possibly do. I think you'll find by the time you purchase the block and machine it you'll have almost as much into it as if you'd picked up a new Dart block like the ones that Carl is getting geared up to sell. And you know it's machined right.

If you are building a 377 the 215 is a good choice if it's a drag car, but if a street or dual purpose car you'll be happier with the 200. Since you are going 12:1 static I assume this is a drag only car. The best way to do this is with flat top pistons and a very small chamber or dish pistons and a very, very small chamber. With a flat top 377 you'll need approximately a 58-60cc head. I know the 55 cc Bowtie phase 6 head will net you 12.3:1 with a flat top 377. With a 406 you won't need quite as small a head. If this is a street car I'd bring the compression down a point to a point in a half depending on the cam you run.

I have a 327 from a 68 camaro you can have for great deal $50.00, it's .040 over but will take a .060 no problem!!

I am in South Arkansas, I have no idea where you are at but the price is right if your close. This will allow you to go 327 (307 crank), 302 (302 crank), 350 (350 crank) or 383 (400 crank).

I have a 327 from a 68 camaro you can have for great deal $50.00, it's .040 over but will take a .060 no problem!!

I am in South Arkansas, I have no idea where you are at but the price is right if your close. This will allow you to go 327 (307 crank), 302 (302 crank), 350 (350 crank) or 383 (400 crank).


Has it been sonic tested as we find there are very few blocks that will go .060 over and be safe for performance use.

thanks, this is going to be a street car, although it may see the track

also, thanks for the offer, but i already have a 327 block sitting at home, i need to get it checked though

edit* i drifted a bit too far, other than checking the webbing and looking for cracks, what else should i look for? I cant do anything to the engine if there is something wrong with it

hey guys, sorry to post another reply, but there is something i need to know.. how much is a 509 400 block worth?

it is just a bare block, that has been mag tested and passed, and also cleaned, im told it looks brand new.

how much should i expect to pay for it??

hey guys, sorry to post another reply, but there is something i need to know.. how much is a 509 400 block worth?

it is just a bare block, that has been mag tested and passed, and also cleaned, im told it looks brand new.

how much should i expect to pay for it??

Have it sonic tested before you buy it.

Have it sonic tested before you buy it.

i dont think that will be possible, the block is located about 75 miles away from home, and im going to look at it tomorrow and hopefully buy it, i mean i guess it is possible to put a deposit on the block and have him get it tested, unless i can find a place up there that does it.

the block tested ok on the mag test though

although what i really need to know right now is how much should i expect to pay for the block?

how much does it cost to get it sonic tested?

what questions do i need to ask the owner? this wouldnt be too much of a problem if the block was closer to me, but the distance is the problem.

I paid $250 for my 509 400 block a year ago. It had very little ridge in the standard bores, core shift looked good, it had been mag checked and cleaned and put in dry temp controlled storage. For that price I was willing to risk a bad sonic check should that have happened. I had it magged and cleaned again before the machine work started.

I have seen them go from $200 on up, I would pay $200 for a block that checks out visually, even if you buy it and it's no good your only out $200, which isn't good but it isn't the end of the world. Sometimes you got to sit back and say "welcome to the world of hot rodding" this art can be a gamble at times.

Has it been sonic tested as we find there are very few blocks that will go .060 over and be safe for performance use.

Yes it was about 13 years ago when I was going to use it. Been sitting since then. Not outside but not dry storage either. To bad he is not local to me.

i dont think that will be possible, the block is located about 75 miles away from home, and im going to look at it tomorrow and hopefully buy it, i mean i guess it is possible to put a deposit on the block and have him get it tested, unless i can find a place up there that does it.

the block tested ok on the mag test though

although what i really need to know right now is how much should i expect to pay for the block?

how much does it cost to get it sonic tested?

what questions do i need to ask the owner? this wouldnt be too much of a problem if the block was closer to me, but the distance is the problem.



We get 40 dolllars to sonic test a block and it does not have to be cleaned either.

thanks

can anyone show me pictures of the core shift on the blocks? especially where the cam bore is?

i would like to see a good one, or at least an OK one, and a really bad one

i tried to search but couldn't find anything, even on google

i did purchase the block, the owner says he builds engines for people, and basically told me everything i needed to know

measuring the cylinder bores (on the ring grooves) gave almost exactly 4.125" on each one, + - 0.002

the groove is barely noticeable, but he said the block has to be bored out, or he would recommend boring it out, he said only .020 over though.. what do you guys think about that? should it be bored, or is a hone good enough?

thanks!

edit* oh yeah, could i get pictures from the bottom end showing the cylinder walls also? one side seemed pretty thick, and the other side seemed a little thin

Does the '68 327 in Arkansas have a forged crank in it?

For $50, I'm interested in a road trip to pick it up and I am at Columbia, MO!

I can just see a 348"er in my little pointy head!

pdq67

Regardless of what you've heard, you can't spot core shift by looking at the cam or lifter bosses. That's another of the old wive's tales that have been perpetuated thru the years. A sonic check is the only way to tell for sure.
I'd have the block cleaned, magged and sonic tested. It's common for these blocks to crack from bolt holes to cooling holes which is no problem. A crack from a bolt or cooling hole to the cylinder bore is a death sentence. They're not always easy to find with the naked eye, even on a clean block, some can't be found without magnafluxing.
I paid $200 for my complete 509 block and it's a good one. It honed to .020 over and doesn't have the center core hole or even a boss on the side of the block, it'll be easy to pass off as a 350 to those who don't know how to spot the differences on the side of the block.
Good luck, I hope it works out for you. I'd see if the guy will let you get it checked before final payment. Most will if you agree to eat the cleaning/magnaflux/sonic check costs if it turns out bad.

Regardless of what you've heard, you can't spot core shift by looking at the cam or lifter bosses. That's another of the old wive's tales that have been perpetuated thru the years. A sonic check is the only way to tell for sure.
I'd have the block cleaned, magged and sonic tested. It's common for these blocks to crack from bolt holes to cooling holes which is no problem. A crack from a bolt or cooling hole to the cylinder bore is a death sentence. They're not always easy to find with the naked eye, even on a clean block, some can't be found without magnafluxing.
I paid $200 for my complete 509 block and it's a good one. It honed to .020 over and doesn't have the center core hole or even a boss on the side of the block, it'll be easy to pass off as a 350 to those who don't know how to spot the differences on the side of the block.
Good luck, I hope it works out for you. I'd see if the guy will let you get it checked before final payment. Most will if you agree to eat the cleaning/magnaflux/sonic check costs if it turns out bad.

thanks, i already purchased the block

it was mag tested, cleaned, and pressure tested

the guy who sold it to me told me that if there is any problems with the block, he would give me my money back, he seemed like a honest guy

so you are saying i can just get the block honed .020 over and not bored?

i want to get it sonic checked soon, i have some nice plans with this block

Have your shop check cylinder bore and taper. It's awfully difficult to bore less than about .030, tool drift toward the bottom of the bores with cheaper equipment is enough to throw it out. I had mine honed on a Sunnen, came out straight and true.
If you're interested, I have a set of KB hyper pistons at .020 over for 5.7" rods, brand new. They have a reverse dome and will net about 9.2:1 with 64cc heads. PM me if interested. I decided to go higher compression with a big cam is the only reason I'm not going to be using these.

Have your shop check cylinder bore and taper. It's awfully difficult to bore less than about .030, tool drift toward the bottom of the bores with cheaper equipment is enough to throw it out. I had mine honed on a Sunnen, came out straight and true.
If you're interested, I have a set of KB hyper pistons at .020 over for 5.7" rods, brand new. They have a reverse dome and will net about 9.2:1 with 64cc heads. PM me if interested. I decided to go higher compression with a big cam is the only reason I'm not going to be using these.

thanks for the help, and for the offer, but im looking for about 13:1 comp on this build

4 bolt main 400 blocks are weaker than 2 bolt 400 blocks. 2 bolt blocks can be drilled and taped to use splayed main caps, I would not bore a stock 400 more than 40 over.

I gotta save ALL this info for later!!

Dave,

I found inexpensive 6.25" long SJ SB rods for my next junk 292/301/306. Thanks to you..

pdq67

4 bolt main 400 blocks are weaker than 2 bolt 400 blocks. 2 bolt blocks can be drilled and taped to use splayed main caps, I would not bore a stock 400 more than 40 over.

yeah, in another thread i was confused.. people were telling me that the eagle/milodon main caps wernt very good.. so i dont know what to do with them now

i mean i dont plan on spinning my engine up to very high rpms.. but its nice to have the added strength and security knowing that the block is strong

i mean.. what is actually stronger, a 4 bolt 350 or a 2 bolt 400.. im betting the 4 bolt 350 would be

im planning on boring it out 20 over, or maybe if it can be done, just honing it and putting stock pistons in it

yeah, in another thread i was confused.. people were telling me that the eagle/milodon main caps wernt very good.. so i dont know what to do with them now

i mean i dont plan on spinning my engine up to very high rpms.. but its nice to have the added strength and security knowing that the block is strong

i mean.. what is actually stronger, a 4 bolt 350 or a 2 bolt 400.. im betting the 4 bolt 350 would be

im planning on boring it out 20 over, or maybe if it can be done, just honing it and putting stock pistons in it

A good 350 block is alot stronger as the deck are stranger cause of the smaller bores also making the webbing stronger pus with the smaller main line the it makes it strnkger as well.


Dart has their new SHP blocks out as we are getting 3 maybe 4 in this week as they are about 500 to 600 cheaper then the Dart Sportsman blocks and are rated at 600 horse and have nodualr iron splayed caps 350 main line only either 4.00 or 4.125 bore.

I have had a lot of calls on thses as far as probing them out for locations I will keep you posted on the out come.

Carl

Paul now all you need is some forged 350 comp height pistons and get the deck cut to zero deck it and you're in business! I'd build 100 of those before I ever spent a dime on a 350. If I had a quarter for every 350 I've destroyed I'd have about $2.75 by now. Never, ever hurt a 302 and run them much, much harder than any 350. Except maybe the last 12.5:1 355 I had recently, but it only held up for 3 months before it split the block in a couple places.

Victimization I don't think there is anything wrong with Milodon or Eagles. I just think Pro-Gram has a better cap. The other two are fine though. I was going to run Eagle caps in my latest project, but they required so much material to be removed to fit the oil pan on the block that the caps are no longer adequately strong enough, so I'm back to the stock 2 bolt caps and studs, filling the splayed holes in the block. I also wanted to make sure you were aware the Milodon isn't a billet cap. Some believe it is just because it's splayed. I know these will all have stepped registers, but that's because the stock block is cut that way.

Paul now all you need is some forged 350 comp height pistons and get the deck cut to zero deck it and you're in business! I'd build 100 of those before I ever spent a dime on a 350. If I had a quarter for every 350 I've destroyed I'd have about $2.75 by now. Never, ever hurt a 302 and run them much, much harder than any 350. Except maybe the last 12.5:1 355 I had recently, but it only held up for 3 months before it split the block in a couple places.

Victimization I don't think there is anything wrong with Milodon or Eagles. I just think Pro-Gram has a better cap. The other two are fine though. I was going to run Eagle caps in my latest project, but they required so much material to be removed to fit the oil pan on the block that the caps are no longer adequately strong enough, so I'm back to the stock 2 bolt caps and studs, filling the splayed holes in the block. I also wanted to make sure you were aware the Milodon isn't a billet cap. Some believe it is just because it's splayed. I know these will all have stepped registers, but that's because the stock block is cut that way.

i assume the eagle isnt a billet cap either?

is there really that much of a difference between billet and non billet?

if i do put the eagle caps on, will i have to worry about spinning it at high rpm?

Eagle is billet. I think even the Dart Little M blocks are nodular splayed caps. Nothing wrong with the Milodons, just not as strong as billet.

I don't think you need to worry as much about the main caps as you do detonation with that CR. I broke two pistons, and as a result bent valves and split the block in two places running 12.5:1 when it detonated badly. Flat tops, small combustion chamber heads, minimum quench, removing any sharp edges to the pistons and chambers, anti-detonation grooves on the top ring land, gas accumulator on the second, good fuel and correct timing schedule, keeping the dynamic compression ratio around 8.5:1, aluminum cylinder heads amoung other factors will help keep you out of trouble with detonation.

Eagle is billet. I think even the Dart Little M blocks are nodular splayed caps. Nothing wrong with the Milodons, just not as strong as billet.

I don't think you need to worry as much about the main caps as you do detonation with that CR. I broke two pistons, and as a result bent valves and split the block in two places running 12.5:1 when it detonated badly. Flat tops, small combustion chamber heads, minimum quench, removing any sharp edges to the pistons and chambers, anti-detonation grooves on the top ring land, gas accumulator on the second, good fuel and correct timing schedule, keeping the dynamic compression ratio around 8.5:1, aluminum cylinder heads amoung other factors will help keep you out of trouble with detonation.

http://www.jegs.com/i/Eagle/356/C4103S/10002/-1

those are billet? i would of thought they would be way more expensive than the milodon ones

Kind of off topic here, but I wanted to get some more insight on 400 blocks.
I have heard that canadian casting 400s have less core shift than american casting 400s. I have also been told that the canadian casting has a higher nickel content and they tend to be around 10-11 lbs heavier than an american cast block. I have one canadian casting block( 330817 2 freeze plugs on each side, 2 bolt main) and one american casting block( 3 freeze plugs, 2 bolt main, 3951511 7-72 date). I took the canadian block to the engine builder last week hoping that it was the better choice of the two. Both of my blocks have never been bored but I bought the canadian block from a local chevrolet engine builder of 40+ years and he cleaned, magged and sonic checked block and said it checked out. I paid $480 for the block. Any comments about the differences in the castings?

Vic, the Eagles are billet steel. The Milodons are high ductile strength iron. Milodon claims their material will better handle shock loads applied to the cranks and bearings compared to the harder billet caps. Nothing wrong with the Milodons other than the price tag. Before I'd spring for those I'd invest in the Pro-Gram billet caps as many of the race teams use, a little less than the Milodons.

Factory main caps can be grey iron or nodular. The nodular are prefered and usually have an N marking on them to indicate such. Bowtie 350 main caps are available in billet steel from GM, but not for your 400.

Either way you go you can't go wrong Milodon or billet. Either way you'll have the huge expense of align boring the block, a special Fel-Pro rear seal for align bored blocks and possible a special shorter length timing chaing if the crank centerline to cam distance changed during the align bore process. These are a few of the reasons I elected to use the factory caps with ARP studs. I'm not shooting nitrous and don't plan on more than 550 hp out of my 377, so the billet caps were a luxury I didn't need.

If you do this and you drill the block yourself using the drill pilot bushing provided by Eagle and Milodon a word of advice from someone who's done it. Don't trust what you'll read regarding how deep you can drill. They'll tell you 1.025" is safe from the register down, but I hit water jacket doing this in two of the holes. Not a problem as I short filled the block and will use sealer on the studs when I plugged the splayed holes. Stay under an inch and use ARP hardened washers with the inside diameter chamfered for the splayed bolt head radius. I can't recall what size to order from ARP, but you can figure it out with a set of calipers. This allows you to go a little shallower and still use the 2.250 hardened splayed end bolts.

thanks for the great advice

will a machine shop guy be able to tell if i will have to use a special timing chain set before doing anything? or will he not know until the boring/honing is done?

i will also take a look at the pro grams i was under the impression they were more expensive than the milodon caps, which is why i was avoiding them

also what would i be looking at (in general) to get the caps installed and bored/honed? $400 or so?

the cooling issues is a myth.
unless you dont have proper cooling any engine will overheat.
.030 over is a 406
.060 over is a 408
anything more is disaster.
427 smallblocks use taller decks.
cant do that with a 400 GM block

I think you have a mistake there re the displacement with overbore.... the last 0.030" of overbore would yield more additional displacement than the one before it...

Remember a 400 is externally balanced. Uses wieghted balancer and flywheel. Cant use your 350 stuff.

I think you have a mistake there re the displacement with overbore.... the last 0.030" of overbore would yield more additional displacement than the one before it...

60 over is 412 ci (actually rounded up would be 413)

his measurment was for boring 40 over, not 60

Remember a 400 is externally balanced. Uses wieghted balancer and flywheel. Cant use your 350 stuff.

i was planning on using a internally balanced crank

thanks for the great advice

will a machine shop guy be able to tell if i will have to use a special timing chain set before doing anything? or will he not know until the boring/honing is done?

i will also take a look at the pro grams i was under the impression they were more expensive than the milodon caps, which is why i was avoiding them

also what would i be looking at (in general) to get the caps installed and bored/honed? $400 or so?


GM cam tunnels are all over the place as the install under size cam bearings and bore them to the correct center to center distance as we have seen cam tunnels of as much as .016 before.

Line boring should not remove any material from the block side and if your line honing per say .003 out and in a perfect world you are only moving the center line .0015

GM cam tunnels are all over the place as the install under size cam bearings and bore them to the correct center to center distance as we have seen cam tunnels of as much as .016 before.

Line boring should not remove any material from the block side and if your line honing per say .003 out and in a perfect world you are only moving the center line .0015

haha can you say that in english?

i got kinda confused reading that

Victim I think Carl is trying to point out that a proper align bore shouldn't remove material from the block side and align hone will remove a max of .003 diameter, which puts the crank .0015 closer to the cam. Also that the cam tunnels as machined vary more than this so not to worry about .0015 and if you are concerned there are solutions available.

I learned a long time ago in hockey when you're breaking out pass the puck up to the faster winger. It's time to pass it to Carl. I'd go with whatever he says, he won't steer you wrong, he knows his stuff and he's doing this everyday. This is a great site!

Victim I think Carl is trying to point out that a proper align bore shouldn't remove material from the block side and align hone will remove a max of .003 diameter, which puts the crank .0015 closer to the cam. Also that the cam tunnels as machined vary more than this so not to worry about .0015 and if you are concerned there are solutions available.

I learned a long time ago in hockey when you're breaking out pass the puck up to the faster winger. It's time to pass it to Carl. I'd go with whatever he says, he won't steer you wrong, he knows his stuff and he's doing this everyday. This is a great site!

Thanks Carl