jt1 Posted October 24, 2005 Share Posted October 24, 2005 Pete, first of all sorry about the troubles. It reminds me of some of my posts. Out of curosity, was that block bored and honed with a torque plate? Usually the stress from the bolt creates a high spot, and the close proximity of the low spot and the bolt hole made me wonder? John Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 24, 2005 Author Share Posted October 24, 2005 Thanks for the kind thoughts, guys. John, no deck plate was used. Not that I like that fact. The builder doesn't have one in that bore size. The other cylinders show the typical wear areas adjacent to the bolts, but the wear area below and adjacent to that steam hole is very much more pronounced. My guess is that there's a crack that developed below the deck in that area and some trash got into it during heat cycling and pushed in on the sleeve. The builder feels bad about this and is quite surprised. He said that if I was one of his crazy dirt track customers or someone who was throwing a bunch of N2O at the thing, he might still be surprised, but since he knows me he can't imagine it was anything I'd done to cause this. He'd like to help, but agrees that finding another standard bore 2-bolt 400 block is going to be VERY difficult. He feels somewhat responsible, but I see it as stuff that just happens. It's not like he could really afford to replace the block anyway. He's a friend, and I'm not going to let him try to fix this, since the fix I want is a new Dart block. I could buy a new GM block for about $700, but I figure I'll splurge on the Dart piece and not have to worry about it again. The builder also wants me to hold onto the block so that when he comes through my area the next time he can pick it up and take it home to find out what happened, to put his mind to ease. If it's a procedural issue with how he or his partner did the sleeve, they want to learn from it. I tried to explain to him that my car is like the twilight zone, and the laws of physics are altered for anything that happens there . The thing is somewhat cursed . I STILL haven't totally ruled out the idea that I somehow caused this with my unorthodox manifold torquing sequence and level. It showed up RIGHT after I did that, and I don't think it's a total coincidence. Of course no one I talk to thinks it had anything to do with it . Kind of like I was saying I'd successfully conducted a cold fusion experiment . The block will be shipped this week to the machine shop. No turning back now! Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted October 24, 2005 Share Posted October 24, 2005 Pete, first of all the cylinder head is off the motor so if you had it honed with deck plates it won't be round anyway no matter how you measured it. Second, that's the problem with 400 blocks especially if you use head bolts instead of studs. Some blocks get good ring seal, others do not and I've seen "eyebrows" near the bolt holes where the rings weren't even touching the cylinder wall. Doing a short fill on the block seems to help alot in my experience. Another thing is head torque, 65 lb-ft seems to help alot vs. 70 lb-ft. With aluminum heads, you really only want to go 65 anyway due to the expansion factor of aluminum. The dart sportsman block is supposed to be good to 1250HP, so I guess if you really need the heavier duty block then I'm grinnin' cause I know you have something up your sleeve that we'd all be proud to see, let alone have for our own. If your using S&S full length headers, they won't clear the block. Also get the dipstick and tube from Chevy, the instruction sheet gives you the GM part #. Weld a nut to the header flange and the dipstick will bolt right to it and keep it in place. Oh, and try to contain yourself when you get the block, better get the wifey some flowers cause you'll spend several hours if not all night admiring the quality piece of work. Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 24, 2005 Author Share Posted October 24, 2005 Dr_Hunt: I realize that even with deck plate hone, I'd see something like what I measured on #2. But #6 is WAY out of wack, no? Also, that was at 1/4" down. A partial block fill may help a bit, but up top, not much if at all. I did go only to 65 lb-ft. 70 seemed to take a good bit of turning on a few bolts so I just went to 65. My builder agrees with you, 65 is all you need on AL heads anyway, since they expand so much more when hot and help the sealing. I tried studs, but you probably remember the bad luck I had with that. Again, that was probably more the MLS gaskets and me not retorquing them than the studs. I'll use the studs on the Dart block though - blind head bolt holes - Hooray! No, the block will be major overkill as far as strength is concerned. But with studs, a torque plate hone, and that stiff block, I should have an excellent ring seal. I was thinking about the gapless rings, but some discussions with builders have me thinking they're not going to gain much over a very stiff block, studs, and deckplate honed hole, with a proper gap. The pin hole left in the gap when it's warm is so small of a leak as to be probably insignificant as far as power production. The only trick I have up my sleeve for this engine is to someday get the Hilborn injector with EFI going on it. But I doubt that it will be more that 550hp ever. I don't plan on nitrous, but you never know if I might get nuts and do that. Maybe lower the compression some day and add some forced induction? Well, the block will be able to handle it anyway! I'm going to build custom headers and use the Canton RR pan, which has a self-contained dipstick, so those problems go away for me. The wife will not be happy if she ever asks what this thing costs. Oh well, it won't be the first time! Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted October 24, 2005 Share Posted October 24, 2005 I've seen the same thing a couple of times, it is my theory that that cylinder wall is thinner than the others in the same block as cast. You know that everything is not always perfect in the GM world. I guess sonic testing blocks is a good idea, but my machinist says that while leaning on a new dart block and he always says, "You could of course spend alittle more and get this." The dart is a step in the right direction and after all the money you poured into the stock block, plus the gaskets, rings and aggravation, doesn't it seem so simple to go Dart????? I think that if Grumpy and I, and I'm sure some others, could combine experience and knowledge and pass it on to you all, we'd all be better off and money ahead. I had 5, count 'em, 4 bolt 400 blocks, been buying them and saving them for years starting in the '70's. Now, I'm getting rid of them all to a buddy for $300 each and you guessed it, buying another dart block. The other big problem I've experienced with the 400's is stripping head bolt holes, and of course you only do that when your installing the heads. So, after decking, align honing, boring and honing with plates, you end up with $650 in the block in machine work alone, probably $1000 when you take into account the block and vatting. Then to run into problems like what you've got there, it just doesn't seem worth it, at least to me and I'm old and busted. The new young guns might like ripping motors back out and building and rebuilding, but I'm just loosing my ability to accept the potential problems with the production blocks especially now that I can work hard and find the $$$ to get it done. The other really nice feature you'll notice with the dart blocks is the blind head bolt holes, no longer will you have to deal with leaking head studs! Whoooppppeeeeeee!!!!!! Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted October 25, 2005 Share Posted October 25, 2005 I dont want to hijack this thread, and i waited till it was about over before i asked this... What is the point of an aftermarket block? what advantages do you get. I dont know what deck height is. When it comes to the bores, this is what i have come to believe. A 305 could not be bored out to 4.000 because the metal in between the cylinders is too good, or pretty weak. Are aftermarket blocks just better quality metal between the cylinders allowing a bigger bore, like past .060 would be safe? Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 25, 2005 Author Share Posted October 25, 2005 From Dart's site: Part# 31131111 / 31131211 / 31132211 Material: Superior iron alloy Bore: 4.00†or 4.125†unfinished Bore & stroke: 4.185†x 3.875†max recommended Cam bearing bore ID: SBC - 2.00†Cam bearings: Special coated, grooved, w/3 oil holes Cam Bearing O.S. + .010â€, +.020â€, +.030†Cam bearing press: .002†Cam journal OD: Standard SBC - 1.869†Cam Plug: 2.375†dia. cup plug Cylinder Wall Thickness: .275†min @ 4.185†bore Deck Height: 9.025†Deck Thickness: .675†min. Fuel Pump: Mechanical pump provision Fuel Pump Pushrod: Standard Length Freeze Plugs: Press in cup plugs Lifter Bores: SBC .8427†- .8437†Main bearing size: 2.450†(350) 2.650†(400) Main bearing bore: (350) 2.6401†/ -.001†(400) 2.8401†/ -.001†Main Cap Bolts: #1 7/16†(2) 3/8†(2) #2, #3, #4 7/16†(2) 7/16†splayed (2) #5 7/16†(2) 3/8†(2) Main cap press: .005†Main caps: Steel - 4 bolt, all 5 Main cap register: Deep stepped register on each side (no need for dowels) Oil system: Wet Sump - Main Priority Oiling (can use dry sump) Oil Pump shaft: 350 main = Stock shaft (.481â€OD) 400 main = Stock shaft (.425â€OD) MUST machine aftermarket shaft Oil Filter: Standard SBC filter, uses 2 bolt filter adapter Oil Pan: Standard SBC oil pan Rear Main Seal 350 main - std seal / 400 main - FelPro# 2909 Serial No. Left front & main caps Starter: Standard SBC Stud holes, Head: Blind holes Timing chain/gears Standard SBC components Timing Cover: Can use stock cover / Magnesium w/ pump provision avail. Torque Specs: 1-5 7/16†bolts - 65 ft lbs 1 & 5 3/8†bolts - 35 ft lbs Weight: 205 lbs @ 4.00†bore I put what I feel are the real advantages in Bold The 400 blocks are thin, and using it past .030" over can be tricky. The Dart block is much beefier in the lower end as well, the thicker walls and decks help as well. That means a better ring seal and a better head seal. The 205 lbs is a 60 lb increase, that's the only drawback I can see, past the price. Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 25, 2005 Author Share Posted October 25, 2005 Dr_Hunt: I fully agree. I wish I'd done it this way the first time. I got a steal on the block, machine work, parts. I paid $1600 for the entire shortblock balanced and blueprinted with a build book. The guy started with a standard bore 400 2-bolt block (from his stash and threw it in with that price), so I figured the cylinder walls would be fine. Little did I know about the sleeve. Wish I'd gone this way to begin with. I'll never do a sleeved engine again, nor accept one built with one. If I ever buy an engine from someone, I will ask before I pay or commission the job. Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted October 25, 2005 Share Posted October 25, 2005 I dont understand how the cylinder wall thinkness can be thicker than a std block? wouldnt that mean more metal between the cylinders? wouldnt that mean the block would be longer, which i think is impossible, cause nothing would line up then.... Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 25, 2005 Author Share Posted October 25, 2005 You're correct - the bore spacing is the same, so there's no more metal BETWEEN the cylinders. But away from where they are siamesed, they are thicker than the 400. On all of the SBC blocks BUT the 400, the walls are separate between the cylinders, meaning they aren't "siamesed". And I doubt you can reliably bore a 305 to 4.000". The wall thickness all around the cylinder isn't there to do that and have any appreciable metal left. I could be wrong on that though. I've never dealt with a 305 and don't see the reason to build one. power=breathing=valvesize to a large degree, and limiting bore size will limit breathing, all else being equal. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted October 25, 2005 Share Posted October 25, 2005 All except the bowtie blocks, which are all siamesed. no, you can't bore a 305 to a 4.00 inch bore and have it work or if it worked, it wouldn't work very long. I knew a guy, Ray Zamora, who bored a 350 to 4.125, lasted about 2 weeks before cracking a cylinder lengthwise from top to bottom. I measured a piece of the cylinder wall and it was .080 thick. Cylinder wall thickness along the wristpin centerline is of no real asset, the thrust faces of the cylinder wall are what take the most stress, and the goal is to achieve the maximum stiffness. If the thinnest portion of the cylinder wall is .800 long where the siamese portion is versus 12 inches long for the 350 (Pi x Dia), which is entire circumference of cylinder, which will be stiffer? So what you get with an aftermarket block is; 1. New std. bore, 2. More material in the cylinder walls at max bore than stock blocks have at std bore., 3. Better oiling., 4. Clearance for stroker cranks up to 3.875 and 4.125 is a breeze without hitting the bottom of the water jacket., 5. Better cam brg oiling for roller camshafts., 6. Blind head bolt holes so you don't have water leakage problems normally associated with studs., 7. Handles more HP!, 8. Dead nuts lifter bores and overall tolerances are better than production blocks., 9. It doesn't make you faster, but it sounds cool to your hotrod buddies when you say, "I have a Dart block". I call it the Ooooooooo factor., 10. You don't end up throwing away $1000 on a production block like Pete did, although he didn't pay $1000 for the block, but somebody did and it could be YOU! There are more little things, but that's what I can think of off the top of my head and #10 is a biggie. Now then why doesn't somebody get an aluminum aftermarket SBC and really shave some weightk, it could have it's own hybridz category "Aluminum Blocks". Deck height is the distance from the crank centerline to the cylinder head mounting surface or deck. Quench head engines like the sbc require .045 or less to achieve quench, at least that's what they say, and .040 or less is preferred. To get that most people in the know deck to 9 inches, which allows you to run an .041 head gasket and still get the quench you need. You don't know it yet but Pete asked santa for a NOS pro shot Fogger system for christmas and he's going to spray 700HP of NOS if he's been a good boy. Rumor has it that he's not been that good, so my money is on a 250 shot. Quote Link to comment Share on other sites More sharing options...
jt1 Posted October 25, 2005 Share Posted October 25, 2005 Minor hijack- Has anybody heard any feedback on the World Products blocks, especially the aluminum one? John Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted October 25, 2005 Share Posted October 25, 2005 All except the bowtie blocks' date=' which are all siamesed. no, you can't bore a 305 to a 4.00 inch bore and have it work or if it worked, it wouldn't work very long. I knew a guy, Ray Zamora, who bored a 350 to 4.125, lasted about 2 weeks before cracking a cylinder lengthwise from top to bottom. I measured a piece of the cylinder wall and it was .080 thick. Cylinder wall thickness along the wristpin centerline is of no real asset, the thrust faces of the cylinder wall are what take the most stress, and the goal is to achieve the maximum stiffness. If the thinnest portion of the cylinder wall is .800 long where the siamese portion is versus 12 inches long for the 350 (Pi x Dia), which is entire circumference of cylinder, which will be stiffer? So what you get with an aftermarket block is; 1. New std. bore, 2. More material in the cylinder walls at max bore than stock blocks have at std bore., 3. Better oiling., 4. Clearance for stroker cranks up to 3.875 and 4.125 is a breeze without hitting the bottom of the water jacket., 5. Better cam brg oiling for roller camshafts., 6. Blind head bolt holes so you don't have water leakage problems normally associated with studs., 7. Handles more HP!, 8. Dead nuts lifter bores and overall tolerances are better than production blocks., 9. It doesn't make you faster, but it sounds cool to your hotrod buddies when you say, "I have a Dart block". I call it the Ooooooooo factor., 10. You don't end up throwing away $1000 on a production block like Pete did, although he didn't pay $1000 for the block, but somebody did and it could be YOU! There are more little things, but that's what I can think of off the top of my head and #10 is a biggie. Now then why doesn't somebody get an aluminum aftermarket SBC and really shave some weightk, it could have it's own hybridz category "Aluminum Blocks". Deck height is the distance from the crank centerline to the cylinder head mounting surface or deck. Quench head engines like the sbc require .045 or less to achieve quench, at least that's what they say, and .040 or less is preferred. To get that most people in the know deck to 9 inches, which allows you to run an .041 head gasket and still get the quench you need. You don't know it yet but Pete asked santa for a NOS pro shot Fogger system for christmas and he's going to spray 700HP of NOS if he's been a good boy. Rumor has it that he's not been that good, so my money is on a 250 shot.[/quote'] Thanks Hunt, that was very informative. I just learned alot. And i just used the 305 as an example, i know it wouldnt work, i just wanted to know why.... I wasnt planning on using a 305, whew, dont think that. I have a little stash of 4 bolt 350's that i use, and my sweet 327 block for my 283 crank Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 31, 2005 Author Share Posted October 31, 2005 Minor update: I removed the pistons, cleaned the carbon off the tops, and removed the rings. I'll take them to the machine shop tomorrow. The machine shop called this afternoon and let me know that the block showed up. That's about 5 business days from me ordering it. My hat is off to CNC-Motorsports.com. Good price ($1806), excellent shipping cost ($75), and it happened in the 5 business days they said it would. Oh, I pulled the caps off of the con rods on the 327 yesterday - #6 had babbet missing, all copper showing, #7 had all babbet missing, about 60% of the copper missing, showing steel backing! The stock nitrided crank just needs a bit of work with sand paper strips and a belt - that's a nice tough finish. The machine shop has some old 327 rods that I'll have them resize and put on the #6 and #7 327 pistons so I can get that engine back in the car. I'll use it to get the car over to the body shop to get the rear end damage fixed while I analize on the 406 Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted November 1, 2005 Share Posted November 1, 2005 Yeah, CNC motorsports is a good place, I bought 2 set of AFR heads from them, really good prices, great shipping and excellent communication. I guess if we can bad mouth some guys, we can give 'em praise when deserved! CNC is one of the best IMO! Quote Link to comment Share on other sites More sharing options...
Michael Posted November 1, 2005 Share Posted November 1, 2005 Pete, Perhaps - just perhaps - it's precisely the engineer's attention to detail and careful checking of tolerances, parts fitment and component matching which somehow offends the engine gods and incites them to curse your efforts? Then, perhaps, a happy-go-lucky slapping together of your next engine will yield 100,000 trouble-free miles, and get you in the 11's? I don't know, but sometimes it does seem that the more one thinks about matters rigorously, the more one gets punished! Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 1, 2005 Author Share Posted November 1, 2005 Believe me, I am following your train of thought - I've been there! Maybe I should lock all my precision tools away while I put this one together? Nah, that wouldn't be any fun, and would actually be torture! Quote Link to comment Share on other sites More sharing options...
BWRex Posted November 1, 2005 Share Posted November 1, 2005 That rubs that the Z isn't preforming,but keep in mind the others that aren't as far along, are still using your platform as an example,so keep us posted! Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 15, 2005 Author Share Posted November 15, 2005 BWRex - good point, but it took me 11 years (off and on) to get this car built! No way I want it down and out again! The wife is NOT happy that it's being "reconstructed" again. Got the Dart block back from the shop after they bored/deck-plate-honed it for the pistons (0.030" bore). $328 for that plus the cleaning. Ouch. This shop is NOT cheap but very good. The thing is beautiful. I have all the piston's rods sorted to fit the holes the best and also stack up to a .003" inch variance in deck height. But the decks need 0.028" cut off of them to get a zero deck height, so more money will be spent. Also working on fixing the 327. The crank needed to be ground (now .010/.010). Two replacement rods were had from the shop's stash. They're rezied, have new ARP bolts, on the pistons and have been balanced to the old one's specs. I honed the cylinders last night - after teaching my 9 year old daughter how to use a .0001" vernier micrometer and a dial bore gage and measuring the #1 bore and piston with her! - She asked tonight to go out in the garage and do the rest! Too bad I had already done them!) I put 400 sand paper on the 220 stones and put a nice fine cross hatch in the cylinders for the Moly rings I just ordered. The 220 grit did a good job of cutting the glaze, but it was too rough IMO. Most moly ring sets instructions say to use 320 or 400 as the final grit. So I'll get the 327 back together this weekend and hopefully in the car soon. The car needs to get to the body shop. I'll have a freshened 327 to sell after that too! Can't wait to get the 400 going again. I've really outgrown the 327 and want that BIG low end punch from the 400 back under the hood! Quote Link to comment Share on other sites More sharing options...
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