Thread: sbc 400 2-bolt main

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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.

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.

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.

this 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..

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..

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