sbc 400 2-bolt main

hay i just got this 400 sbc it is 60 over, afr 210cc 202 aluminum heads, with a long stroke rods all balanced and blue printed in side and out, with forged dome top pistons
i sill have to get a cam and in take, basically a top end i wanted to make it around 550 horses (this is my first hp engine) but when i flipped it over i found that it is a 2-bolt main, all the old school dudes have been telling me that i should of got the 4-bolt or make it a 4-bolt main, (ow and its a high nickel block at least when i looked up the block it said it was 2% nickel) so my ? is is this a good block for hp? i dont want dump a lot of $$$ in to it just blow it up with one good run... if you could help thanks..

Welcome and the best thing you could do is convert it to splayed 4 bolt caps----the outer bolts are angled out toward the pan rails which really helps tie the bottom end together

iv seen them and you think that would hold it to gether?

i was all so thinking of putting solid roller lifters with a lopy cam heavy springs but i dont know about the in take

Intakes are easy===themains will take a align bore/hone job

Welcome to CHR!

I’d be concerned about a .060 over bore in a 400 long before I’d be concerned with the 2 versus 4 bolt mains. As Jerry stated, they are a good candidate for the splayed 4 bolt conversion and I certainly agree with him that it would hold the lower end together however; but bring a bunch of money to your machine shop. Was the block sonic tested after the boring? The .060 over on the Siamese blocks is really pushing it as their design (two cylinders actually touching) is not as efficient in the cooling department and they are prone to “hot spots” where the cylinders touch. Removing .060 doesn’t leave a lot of cylinder wall.

That said – you didn’t tell us what you have in mind for the engine – when you say “one run” does this mean you’re going to drag race this engine? Why 550 HP? What is this engine going to go in?

Before cam selection it would help to know; rear end ratio, tire size, transmission (manual or automatic) and stall (if auto) would be good to know as well.

Give us a bit more info and there’s a lot of help on this site!

Again, welcome to CHR,
Glenn

well two more bolt holes in the mains of a weak block to start with . stud the two bolt main use a main girdle . splayed would work .but buy caps.. fit the caps . line bore block . then deck with BHJ tru-deck .then bore hone block with deck plates .now you want to push this block to ?? how many Hp 550 it should hold it but if your going to go with the block work you may want to look at a SHP dart block

To Pat's point - it will cost a boatload of money for additional machine work and splayed caps - get us the additional information I asked for above and we can help you with a cam and intake/carb and you may want to call it a day and run it as is.. Although as cold as it in in Northpole Alaska - ya may not have any heat issues:LOL:

well like i said im new at this im a mechanic fresh at of collage i havent decided what to put it in , the guy i got it from didnt say if it was a long block or not , but i do have a 78 280z in the back yard, thay have lotts of kitts for those cars ,so what do you think im i going about this all wrong ? and with all the balancing and blue printing they would check the block (i have all the paper work with the engine and ive opened it up its had a lot of woke done) so some direction would help thanks....**)

It is possible with 400's and the best efforts to leak down one a number of times and get a number of different results because the cylinders do move quite a bit.The logic behind aftermarket blocks is the failure of the OEM stuff.When you start talking about 550 hp,there is a formula for dollars spent per each 1 hp.So it as always comes down to your budget.

I knew of a guy with a 406 in a Super Gas car.It had a cast crank,high stall convertor and tranny brake.He along with all of us called that a grenade with the pin pulled on each run.If it wasn't for fact he couldn't afford anything else at that point,he won't have tried that.Got to the end of the season and tore it down.Bottom end was trash.If your thinking of a big time spray on this,I suggest to limit that.

sounds to me like he has a lot of good parts and other work already done on the top side---these caps can be put on the 3 center mains and actually make the block a lot stronger because the outter bolts are angled(splayed) out inti the outter pan rail/main web junction. I do from 2 to 5 of these jobs every week and find that the eagle caps are cheap compared to the programs, milodons etc (well under c-note) and takes total of about an hour to install the caps and another hour to align bore then finish align hone block

Its all he needs to do , its simple (if the shop has the equipment) and about the only machine shops who won't recommend it are the shops who don't have the equipment or the knowledge/experience to do it.

it is what ever he wants to do and how much the shop gets to do the job your talking 150 in mich for line bore then caps 107to 170 milodons 222.fit drill for caps . so lets stay 400.?to 500. more hard to stay what they get for the job were he is at. as for saying the shop would talk you out of this and a better block if the shop did not have aline bore or line hone that can go both ways were a shop would talk you in to a job if they had aline bore ?

Pat the eagle caps are way less than $100----

My two cents worth(normally a dollar charge but discounted for here.:rolleyes::LOL:),is now you have strengthen the bottom end and still have a cast crank.Sure don't have much of a future at 550 hp with that.:HMMM:

never look at them thats just prices out of comp :) for them caps

how old do you have to be a old school dude ?????

Jerry-I have never hidden my hatred for Eagle.Just for the sake of discussion,next time you have a set of Eagle caps,run a Rockwell hardness test on them.I would be interested in what you found.

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Originally Posted by 1gary

Jerry-I have never hidden my hatred for Eagle.Just for the sake of discussion,next time you have a set of Eagle caps,run a Rockwell hardness test on them.I would be interested in what you found.

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most good caps are some what soft steel so they flex and not bust cheap caps can have hard spots in them making them not to hot to finsh

Pat,just I have a gut feeling about them.A lot of the time things are cheaper for a reason.

Yes, they are nitrated or something but once you cut thru that they machine pretty nice---I really like the milodon nodular caps but them and the programs are expensive----we are doing conversions on sbc 2 bolt blocks because its almost impossible to find any decent 4 bolt blocks these days--the 4 bolt blocks are pretty old, rusted away on outside, broken bolts, cracked mounting ears in back, etc--two bolt one pc seal blocks are reasonably available and we are putting a lot of splayed bolt caps on--also have billet 2 pc seal adapters from K tech but they are expensive---can get the dogbones and spider trays for the roller cam blocks----also do a lot of dart shp blocks

just line bored a sbc 4 bolt one pc seal engine sunday still can find them and older 350 4 bolts .bbc are much harded to fine any kind two or 4 bolt mains

Like others have said - .060 over is death for a 400. As far as splayed caps, you really need the '509' australian blocks with the thick webs. When align bore it is best to offset the bore to the cap side, you really do not want to move that crank any closer to the cam - things bump into each other enough and you'll get a sloppy timing chain unless you by a special 'shorter' chain.
In brief, us old schoolers have been thru this and now you can just buy an aftermarket block taht is way better than anything we could make and for a whole lot less money.

We sell the Dart SHP sbc blocks for 1450---they need to be honed to piston size--by the time you pay for sizing bores to pistons(they are .010 undersize)this is only about 600 more than a oem type block fully machined and painted.
400 blocks are very scarce and the local dirt track stock car guys run them. biggest recurring common fault is cracking from cylinder to bolt or steam holes.see the pic in my gallery of this on a 400 block--i couldn't get it over here but maybe someelse will post it--first picture in the gallery--
The angle bolt mains bolt into the otter rail so the thickness of the web isn't an issue, in fact the two bolt blocks converted to splayed caps is preferred as the stock 4 bolt blocks DO have weak webs because of the extra bolt holes in them.

http://www.clubhotrod.com/photopost/...6_640x427_.jpgthis came thru as a thumbnail---if someone can post it full size you will be able to see the cracks and also how someone has plugged the steam holes on this on--and yes it has a sleeve

Heres my 509 block, they have 2 freeze plugs instead of the normal 3. I guarantee this cost me a whole lot more to build than what is available nowadays.

Thanks Louey---

you can see that this cylinder has been sleeved and the steam holes plugged and the cracks that are common especially after the circle burners have timed them by ear and had some detonation

I was curious about the cracks and tried to zoom in and crop the pic. The cracks seem to have a circular shape to them before they get to the cylinder. Let's see if this worked..

I guess I could've made it larger still... but you can see the circles below the bolt holes.. Still curious.. LOL..

Quote:

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Originally Posted by tdwaligorski

hay i just got this 400 sbc it is 60 over, afr 210cc 202 aluminum heads, with a long stroke rods all balanced and blue printed in side and out, with forged dome top pistons
i sill have to get a cam and in take, basically a top end i wanted to make it around 550 horses (this is my first hp engine) but when i flipped it over i found that it is a 2-bolt main, all the old school dudes have been telling me that i should of got the 4-bolt or make it a 4-bolt main, (ow and its a high nickel block at least when i looked up the block it said it was 2% nickel) so my ? is is this a good block for hp? i dont want dump a lot of $$$ in to it just blow it up with one good run... if you could help thanks..

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Good friends-I am not preaching here,but we did get off topic in the process of four bolt main conversions somewhat.Here what I suggest directly to his question.

Sir-it is the combined situation of the 210 cc heads and the costs to convert it to a four bolt main still leaving you with a cast crank that I think you do have a combo issue.I don't think it is advisable for you to spin the engine that high to make those heads work well with that port size with only a 2 bolt main.To change to a four bolt main isn't cheap as the other posts suggest.To move to a aftermarket block in the long term is a better solution and a better financial move,but it still leaves you with a limited capability of a cast crank.The bolt main and the limited cast crank along with the cc heads is the core problem,well really the cc runner and the cast crank is.No way would I suggest you spin it up to 7,000 with a cast crank to really get the advantage of the 220 cc runners.You said you I have long rods,but no detail on what those are too.So to get back to my point,you can't really back down the rpm range because of how huge the 220's are and you can't really spin up that cast crank for very long to use those 220cc runners either.So aftermarket block,four bolt block conversion,you need to do something about that combo either sell off the heads for something smaller and do the four bolt conversion lowing the RPM's using the cast crank or replace the crank with a forged crank that can handle the high rpm and buying into a aftermarket block,but still leaving a question on which rods you have.This option being the best one.Oh one other middle price option would be four bolt conversion/forged crank.

Again-you didn't say if your intended use was to spray it and how much or any other power adders.

When you get into that size head runner,it gets expensive needing all the other parts.Those heads are not really for street use.

I believe that's where Jerry says they / or someone plugged the steam holes.

This was not a block we had originally done--it only came here for some touch up--we sent them on there way to get another block

The circles are some aluminum plugs hammered into the steam holes but you can see where they have common tendecies to crack

Quote:

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Originally Posted by 34_40

I was curious about the cracks and tried to zoom in and crop the pic. The cracks seem to have a circular shape to them before they get to the cylinder. Let's see if this worked..

I guess I could've made it larger still... but you can see the circles below the bolt holes.. Still curious.. LOL..

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Those are the steam holes Jerry is talking about, they have been plugged here. I tap my holes and stick an allen screw in there. I tap those big holes above the stud as well and have pipe plugs in there with 1/4" holes drilled in them for water/steam.

Quote:

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Originally Posted by 1gary

Good friends-I am not preaching here,but we did get off topic in the process of four bolt main conversions somewhat.Here what I suggest directly to his question.

Sir-it is the combined situation of the 210 cc heads and the costs to convert it to a four bolt main still leaving you with a cast crank that I think you do have a combo issue.I don't think it is advisable for you to spin the engine that high to make those heads work well with that port size with only a 2 bolt main.To change to a four bolt main isn't cheap as the other posts suggest.To move to a aftermarket block in the long term is a better solution and a better financial move,but it still leaves you with a limited capability of a cast crank.The bolt main and the limited cast crank along with the cc heads is the core problem,well really the cc runner and the cast crank is.No way would I suggest you spin it up to 7,000 with a cast crank to really get the advantage of the 220 cc runners.You said you I have long rods,but no detail on what those are too.So to get back to my point,you can't really back down the rpm range because of how huge the 220's are and you can't really spin up that cast crank for very long to use those 220cc runners either.So aftermarket block,four bolt block conversion,you need to do something about that combo either sell off the heads for something smaller and do the four bolt conversion lowing the RPM's using the cast crank or replace the crank with a forged crank that can handle the high rpm and buying into a aftermarket block,but still leaving a question on which rods you have.This option being the best one.Oh one other middle price option would be four bolt conversion/forged crank.

Again-you didn't say if your intended use was to spray it and how much or any other power adders.

When you get into that size head runner,it gets expensive needing all the other parts.Those heads are not really for street use.

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:rolleyes::LOL::LOL:Man the wheels fell off on this guys question.

:p

I think his question got answered, with some other info and opinions tossed into the salad as well! LOL... The rest is just sharing information and experiences I think..