401 short block

Discussion in ''Da Nailhead' started by 66GSconv., Feb 9, 2011.

  1. 66GSconv.

    66GSconv. Well-Known Member

    I'm getting ready to start the rebuild of the motor.I was going to hand it over to a board member here but, I have decided to have the short block rebuilt ( block and rotating assembly)I figure I could install the heads the cam, timing set, lifters and some push rods.etc....I'm going to debur the block is there any other spot other than the valley and some window dressing on the outside of the block?But more importane is there any thing that I should tell the machine shop to do or not to do?Anything to make it a better block or stronger block? Also were is a good place to get some of the parts to do a rebuild? Egge$$$$
    Thanks for your help
     
  2. doc

    doc Well-Known Member

    I always swab all the oil passages out with a rifle cleaning brush.... also run a tap down in all the bolt holes and blow them out with compressed air.... and like you said all the knuckle skinning flash on the outside,,,, when a engine is clean enough to eat out of, it is clean enough to put together.... be sure to run a rifle cleaning brush thru the oil holes in the crank..... ck inside the new oil pump for burrs.... clean up the exhaust manifolds and port match them to the heads....and paint them.... get the old cam bearings out before starting on the block.... look at my list of cheap tricks for additional info.....
    While the rocker arm assemblies are off ,,, soak them in simple green for 24 hrs... and pull the plugs out of the ends of the shafts and swab them out with a brush.... simple green is your friend when you are cleaning a engine up....
     
  3. telriv

    telriv Founders Club Member

    Be VERY cautious on who you use. Good parts for a "Nail" aren't cheap. If at all possible stay with "Name" brand parts. In comparison "Egge" is one of the less expensive, not on all, but many. Pay attention to the details. It's mostly all common sense & old hot rodding tricks. Just don't let them sell you hardened seats or use SBC or SBF building tactics, you won't end up happy..
     
  4. doc

    doc Well-Known Member

    Yep, what Tom says.... dont ever build a nailhead loose like a chebby.... build it to exact buick specs and then break it in right and it will run good and last a long time....be sure to use zddp in the oil.....
     
  5. 66GSconv.

    66GSconv. Well-Known Member

    Guru,(Tom) would it be possible to get a list of goodies that you work with and recommend to use.Lets start with push rods,lifters,timing gears,a cam with 112-114 degree of seperation,main & rod bearings,piston rings.What gasket set do you recommend? I"m planing on using arp bolts,and a set of your roller tips.And if I've have forgotten anything please put it on the list of things to get.
     
  6. wkillgs

    wkillgs Gold Level Contributor

    Greg, the best engine build manual is the 1965-66 Buick Chassis Manual. It's online at either www.65gs.com or www.teambuick.com
    More good reading:
    A couple of good Nailhead build article links listed on this post:
    http://65gs.com/board/index.php/topic,145.0.html

    I'm looking forward to Tom's recommendations, but I'll start...maybe I'll save him some typing, or he can correct me, or list better options!
    Pistons: Egge Machine may be the only present supplier??
    Were also offered by Badger and Zollner in the past. Maybe Sealed Power too.
    Rings.... 401 is same bore size as 67-up 430(Edit). Lots of choices there. I went with Hastings moly rings on my 0.020" over 401 since it was an unusual size.
    Cam Bearings: Durabond makes some real nice ones. Any cam bearing may have to be honed or shaved slightly to fit the cam. Doc and I have a good method for that!
    Rod bearings: Same as 455
    Main Bearings: These were scarce and expensive a few years ago. I don't know the current situation.
    Oil pump and timing chain/gears: Melling still makes quality stock replacements.
    Gasket sets: Fel-pro and Best Gaskets offer complete sets.
    Cam/lifters: ...the more I learn, the less I know!!:Dou:
    Comp cams has a bunch of options ranging from a bit-over-stock 212/218 duration to custom-made combos like a 218/230. Compression ratio, gearing, and valve-piston clearance will determine the best combo.
    Heads: A standard rebuild by a local shop consisting of cleaning, magnafluxing, guide replacement, cutting for seals, valve job, new springs and seals can cost $800++. For $899 you can have a Buick pro like greg Gessler do them:
    http://gesslerheadporting.com/gessl...9be03ed92964066b85256dd80027777d!OpenDocument
    :TU:

    We sure do need a good rebuild thread here!
     
    Last edited: Feb 14, 2011
  7. gsgtx

    gsgtx Silver Level contributor

    Walt, i know theres nothing wrong with cast pistons but would any of the 3 pistons you said would move the pin height so the pistons would not be so far in the hole 50-55 thousands. the main bearing are out there, Carmen has them too.
     
  8. wkillgs

    wkillgs Gold Level Contributor

    Stock engines have pistons approx 0.040" to 0.060" down in the bore....that won't produce the advertised 10.25:1 compression ratio, but more in the 9.8:1 range, using a steel head gasket.
    Compression height (or pin height) and dome volume would be the factors that determine the pistons compression ratio....

    Silvolite lists new 401 pistons. Summit and Jegs sell them, about $420 a set.
    http://www.kb-silvolite.com/silv-o-lite/spistons.php?action=details&S_id=707

    .....they list the compression height at 1.912"
    I have a set of 425 Ross forgings with CH of 1.93" The Zollners I got yesterday measure around 1.925" A stocker I checked is a bit higher at 1.93-something. Dome volumes would have to be measured for a fair comparison, but it appears the replacement pistons would all give a CR in the 9's without shaving the deck surface or heads.

    It annoys me that there still isn't an off-the-shelf performance piston for a Nailhead!:rant:
     
  9. John Codman

    John Codman Platinum Level Contributor


    Amen to what Tom says. I got a complete set of rockers, shafts, and stands from Kanter. The engine builder checked the rocker geometry and although the shafts and stands were fine, the rockers did not match the originals. In fairness to Kanter, they were great about taking them back - even though more then the 30-day return period had elapsed.
     
  10. gsgtx

    gsgtx Silver Level contributor

    for the sivolite they list the dome as .370 is that close to the stock one?
     
  11. wkillgs

    wkillgs Gold Level Contributor

    Just measured a couple stockers .... varies from 0.360 to 0.390", but these are rough cast tops.
    The Zollners I just got have machined tops and measure 0.370" .....I measured the volume of the domes on those and they were 46.5 cc
    A couple stock 401 pistons I checked were 45.5 to 46cc
     
  12. gsgtx

    gsgtx Silver Level contributor

    thanks Walt.your on the ball.
     
  13. JZRIV

    JZRIV Platinum Level Contributor

    I used these folks, http://stores.ebay.com/Falcon-Sales-e-Store quite a bit on my recent rebuild. Everything I got appeared to be high quality, name brand, and very competitively priced........although I haven't started the engine yet. :(

    First time using "Best" brand gaskets and I was really happy with them. I'll definitely use them again.
    I got new rocker shafts and misc assembly parts from Tom Telesco
     
  14. wkillgs

    wkillgs Gold Level Contributor

    Yes, I've bought a few items from Falcon too....Durabond cam bearings, and Hastings piston rings.
    Jason, can you be more specific which parts and brands you bought from Falcon?

    And if you could fill us in on what Tom has available, you would save him some typing.:grin:
     
  15. telriv

    telriv Founders Club Member

    Just measured some stock Buick pistons removed from engines. '65/401 piston, Part Number 1185486. Pin weight 223 grams. Piston weight 671 grams for a total of 894 grams. 1.925" compression height. Dome height .380". '65/425 piston, Part Number 1354591. Pin 223, piston 725 total=948. 1.922" compression height. Dome .330".
    Most of the pistons, I feel, are very poor quality. Like Walt said, some have rough cast domes while others are machined. Unfortunately forged pistons, many custom, are higher quality but considerably more $$$$$!!!! Then again, in most cases they won't have to be balanced. They should all be close to the same weights. So with custom there is the $$$ savings of not having to balance, just check.
    Don't forget by using a composite head gasket this will lower the compression aprox. .44. So now you have low 9's in compression. Our "Nails" can run 9.9-1 to 10.1-1 using today's high test,92-93 octane, fuel & a good ignition advance curve because of the PentRoof Combustion Chamber Design.
    If you use composite head gaskets you will now have to deck the block & or cut the heads, but the intake will still line-up. Will have to check real close piston to head clearances. The edges of the domes are squared off & the combustion chamber is rounded. Custom pistons you have to take a mold of the combustion chamber with the head attached to the engine. This way the edges of the "Dome" are correctly shaped.
    Main bearing sets are still out there from Clevite, etc. Mostly what's out there now is what are called "Rebuilder" bearings. Quality ????. This is what Carmen & others are now carrying. I still have available & can get Quality bearings. Standard sizes aren't to hard to come by, but the over sizes are. As time goes on they are becoming harder to come by & as they become harder to come by the $$$$$ go UP!!!!
    Good rod bearings are still available as well as the "Durabond" cam bearings.
    As far as cam recommendations. It all depends on your "Build". What are your (seems I say this a lot) Dreams, wishes, desires & final outcome. What are you expecting to do & your expectations?????
    Rings, many variations available, but DON'T go more than .030" over. There is a gap on ring availability from 4.22"-4.25". Hastings will make you custom, file fit rings at a higher $$$ of course. As an example one '65401 I did the machinist called & said that the engine needed to go to .040" over. I cautioned him on this citing what I just mentioned. The supplier of the pistons said "No Problem". As I started assembling, of course you test fit the rings & came up with .035"+ end gap. NO GOOD!!!!! What do we do now. You guessed it the supplier had to get customs rings made for me by Hastings. He wasn't happy to say the least.
    Use ARP rod bolts. Get the rods magna-fluxed then shot peened, re-sized & then balanced.
    That's all for now.
     
  16. wkillgs

    wkillgs Gold Level Contributor

    Greg, if you want to start by making a parts list, you can find most rebuild items in the TA Performance catalog.
    http://www.taperformance.com/
     
  17. gsgtx

    gsgtx Silver Level contributor

    too bad the kb-silvolite pistons have the pin at 1.912 :confused: , really put the piston in the hole even more.i would rather run them then forged pistons,more advantges and the price is great.
     
  18. telriv

    telriv Founders Club Member

    Besides the $$$ what do you feel are the advantages of cast over forged?????
     
  19. gsgtx

    gsgtx Silver Level contributor

    HI Tom. the silvolite are hypereutectic with more silicon, makes them stronger than stock cast pistons, yes not as strong as forged pistons. you run tighter side wall clearance for better ring seal 2-2.5 thousands.they also have a high top ring which puts heat into the chamber. there lighter too. you have to gap the top ring a little wider for the heat expands the ring.the down side if you have a lot of pinging the pistons will blow a part sooner than forged.
     
  20. telriv

    telriv Founders Club Member

    Just my opinion. I WOULDN'T USE HYPERS IN ANYTHING!!!!!!!!
     

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