Upon tear down and inspection of my first performance engine:

So do i take the block and crank and rods to the guy and say hey look at the junk you sold me? Or do I just take my business elsewhere? Otherwise i get along with the guy pretty good, and I do take him head resurfacing jobs fairly often, thats a pretty straight forward thing you cant fuck up. He already said he would repalce the crank, but IDK if I want another one from him.
 
What part of your situation are you blaming on the machine shop? The
.004 runout? How long was this thing together? Did you not check the
runout when you were putting it together? I'd be more inclined to have it
ground .010/.010 and put it back together. I think it's taken it's share of
abuse for what it is. It would be hard to blame the guy all this time later
after the use you've gotten out of it.

Edit:I just re-read your earlier post and realized it isn't runout, just the snout being "out of round" .004". The only things that would be affected by that would be balancer fit, and front seal. .004" probably isn't enough to affect the seal.
How did you check this with an indicator?
 
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Thats the whole thing, the thing has been leaking oil from the front seal since it was put together because of the crank run out. I didnt want to believe the crank was bad and though I just had a shitty timing cover or fucked up balancer. I verified the crank being out with a dial indicator mounted to the block on the pan rails out of the vehicle (obviously they were clean with the pointer on the crank istelf, not the balancer). At that point I SOHULD have repalced the crank but i was told by that machinist and another the seal should take care of that. Obviously it never did and here I am now.

I dont expect anything from the guy really but I was curious if I should take him the crank and block and rods/pistons and let him give his opinion. He already said he'd repalce the crank but as stated, I dont think another one from him would be a good idea. Oh yeah BTW it was ground .020 to begin with.
 
fastredgmc said:
Just what i thought. That 4th main appears to be shifting back and forth causing those wear marks (Cap walk). The two main bolts arn't just holding it enough at that power level. Is the any metal transfer where the cap meets the block or any strange marks?

350hp @ 6000 rpm is about the safe limit for your setup there to last a good amount of time.

but if it put down 300 thats only 350-370 fwhp.

hmmmm.....
It could also be caused by in correct torque.

if you have a dial bore gauge check to see of its out of round at all.

I just get a 4 bolt block to have some better priece of mind and so it might be able to handle any upgrade later on
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I don't believe that at all. Dads 406 made 532HP on the dyno, was spun well past 6K (A LOT), and that lasted for years on a stock 2 bolt block.
 
HemiChallenger said:
Thats the whole thing, the thing has been leaking oil from the front seal since it was put together because of the crank run out. I didnt want to believe the crank was bad and though I just had a shitty timing cover or fucked up balancer. I verified the crank being out with a dial indicator mounted to the block on the pan rails out of the vehicle (obviously they were clean with the pointer on the crank istelf, not the balancer). At that point I SOHULD have repalced the crank but i was told by that machinist and another the seal should take care of that. Obviously it never did and here I am now.

I dont expect anything from the guy really but I was curious if I should take him the crank and block and rods/pistons and let him give his opinion. He already said he'd repalce the crank but as stated, I dont think another one from him would be a good idea. Oh yeah BTW it was ground .020 to begin with.
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Hell Joe, if he'll replace the crank, do it. Just check the new one out with
the two outer mains on it and get on with putting it back together.
There's not much else to do in my opinion. New bearings, rings, oil pump,
button her up, tear it up for another year.:peelout:
 
The 2 bolts blocks are stronger around the web from what I hear. Splay a 2 bolt and its stronger than a 4 bolt ever will be.
My camino only has a two bolt and should make about 430 or so
 
502SS said:
I don't believe that at all. Dads 406 made 532HP on the dyno, was spun well past 6K (A LOT), and that lasted for years on a stock 2 bolt block.
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Thats a 400 though. Look at a 2 bolt 400 cap compared to another small block it has alot more more metal in it and alot more cap to block contact.

2 bolt 400s are stronger than 4 bolt 400's. The 4 bolt 400s are weaker because of the 400 mains being bigger and having 2 bolts per side wich makes for a lot less metal in the webbing area.

As for the other small blocks such as a 350 the 4 bolts are stronger than a two bolt. I never said a 2 bolt would not work at all but 350hp is starting to get up there and is considered about the safe point to many. 4 bolt blocks are all over and can be had for about $100-200

As far im concerned the spayed caps are a waste of time inmo. A Regular 4 bolt will do just fine for most. If you really need the splayed main setup you might as well step up to a dart block it will be very close to the price at the end but still be way stonger than the weaker GM casitng that still has its flaws in it.

Now Ill open a big can worms:icon_mrgr my 489 stroker big block is a 2 bolt main with around 600hp just shows you how much beefier a big block cap is. I am using studs though as a bit of extra insurance,
 
A fully machined ready to be assembled 2-bolt 350 converted to a spalyed 4-bolt is wayyyyyy less than a DART or World blcok. Plus 350 parts are much cheaper than 4.125 bore stuff and longer stroke cranks.
 
HemiChallenger said:
A fully machined ready to be assembled 2-bolt 350 converted to a spalyed 4-bolt is wayyyyyy less than a DART or World blcok. Plus 350 parts are much cheaper than 4.125 bore stuff and longer stroke cranks.
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mildon caps alone are over 200. than you have to pay for machine work to have them fit. it will cost about 600-700 incuding caps to have the splayed caps done right. than you still have to deck the block est$175 bore and hone it plates $200. now that deosn't include the block it self, having it cleaned having it checked haveing the cam bearing installed. and you still have the stock 2 bolt mains in the fornt and rear.

do all that work and you still have a inferior Gm stock casting. You can get a bowtie sprtsman block starting at 1600 and dart for about 1800 they might need a little work to be readdy to assemble but the features those blocks have make it well worth it. the iron is much better insdie them the decks are thicker the oiling system is better. if youve never worked on one i can tell you they are alot harder then the stock iron.

You can also have them in 4" bore and with 350 mains.

A stock 4 bolt main small block is plenty fine for what most will ever use it for though. Funny thing though if you looked in a GMPP catalog i believe a stock 4 bolt is only rated by Gm at 350hp:laugh:

I found a good post for you to read through

http://www.chevelles.com/forums/showthread.php?t=38173
 
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http://www.sdpc2000.com/catalog/387...50-Main-Cast-Iron-Bow-Tie-Sportsman-Block.htm

That block might need a little work like a hone and cam bearings put in but its a nice piece. Way better than any stock block. Id condiser it if i were going near 600-650hp. Anything lower than that a 4 bolt with good machine work will do especially for a street strip engine. The splayed cap on a stock block just are not really cost effective at all.

read that link I provided above lots of good info in there from guys that do nothing but blocks.
 
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I can get a Dart Little M for around $1500 ready for cyl hone.
For what you're doing, a studded 2 bolt will be fine.
If it were me, I'd buy a $100-$150. 4 bolt -010 block and put the time
and money in it to be safe to 500 h.p. You could get it bored and honed
for around $15. a hole. Most don't need deck or line hone.
That's under $400 ready to assemble.
As for the BBC stuff, many 2 bolt studded stock blocks out there over 700 h.p. n/a. Even the stock truck rods are fine to that level with good bolts.
 
fastredgmc said:
Thats a 400 though. Look at a 2 bolt 400 cap compared to another small block it has alot more more metal in it and alot more cap to block contact.

2 bolt 400s are stronger than 4 bolt 400's. The 4 bolt 400s are weaker because of the 400 mains being bigger and having 2 bolts per side wich makes for a lot less metal in the webbing area.

As for the other small blocks such as a 350 the 4 bolts are stronger than a two bolt. I never said a 2 bolt would not work at all but 350hp is starting to get up there and is considered about the safe point to many. 4 bolt blocks are all over and can be had for about $100-200

As far im concerned the spayed caps are a waste of time inmo. A Regular 4 bolt will do just fine for most. If you really need the splayed main setup you might as well step up to a dart block it will be very close to the price at the end but still be way stonger than the weaker GM casitng that still has its flaws in it.

Now Ill open a big can worms:icon_mrgr my 489 stroker big block is a 2 bolt main with around 600hp just shows you how much beefier a big block cap is. I am using studs though as a bit of extra insurance,
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I also know 2 guys running AFR headed 2 bolt 355's. 1 runs a 150 shot on top of that, and the other runs a procharger. No problems on either of those. I do agree that it seems you're better off getting a Dart block/etc. rather than going through the cost of splaying a 2 bolt block.
 
i have also ran a heads cam 150 shot on a lt1 with 2 bolt mains and have not had a problem i also am i believer of a 2 bolt block with splayed caps for bigger power combo's definately when you do the block though just get the whole thing done align hone, decked, and cylinder honed and get the oil passages threaded and screw plugged also be careful of running oil pick up tubes without tack welding them on or something similar just be sure there is extra safety for the pick up tube the bolt down tubes are nice if yur ganna do a cheap bottom end just run a stock crank with some aftermarket i beams and some light pistons keep light as possible then this way you know yur bottom end is good and won't have to worry about it secondly man that thing sounds like it needs a real set of heads
 
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