MY 1966 Buick Skylark Gran Sport! - FINALLY

Discussion in 'Members Rides' started by 66BulldogGS, Jun 7, 2013.

  1. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Specs for the forged pistons I am getting through Tom T. Putting this information in here for later reference. I am told pistons are finally on order and should be ready another week or 2. Keeping my fingers crossed. I am ready to get this engine build wrapped up so I can get it ready to go back in the car.

    Deck: finished-10.009"
    Rod length finished-6.215"
    Stock stroke-3.640"
    Bore-4.233"
    Rings-1/16th.
    Pressed pin-1.00"
    Desired SCR-10.0-1
    Finished combustion chamber CC's-127
    Head gasket-steel-4.250" x .016" compressed
    Piston-Deck-.020"
    Pin Height-1.954"
    Quench/Squish-.036"
     
  2. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Pistons are in! Now to be fitted, coated, pressed to the rods, and the engine balanced. Hopefully progress continues more rapidly.

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  3. telriv

    telriv Well-Known Member

    What do you mean by "Coated" Johnny????
     
  4. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    I plan to take them to a local company called PolyDyn. They specialize in different coatings for all kinds of applications. For pistons there are 3 different coatings if I remember correctly. They ceramic coat the tops of the pistons for heat protection and distribution, then a dry film lubricant coating to the skirt, and the 3rd I believe is an oil shedding coating to the underside. Not positive about the 3rd but I believe they apply that as well.
     
  5. telriv

    telriv Well-Known Member

    Ceramic coating to the top is for heat retention when using aluminum heads. I would do MORE research on this BEFORE proceeding. On the dry film coating, these skirts are "Wavy" for oil retention & lubrication. Do you really think they need more protection???
    Just my thoughts.


    Tom T.
     
  6. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Understood and valid points. My thoughts are the Nailhead needs all the help it can get. The more heat I can keep in the cylinder and not soaking into the pistons, I feel like will aid in combustion and therefore run a bit cleaner and stronger. Also may help protect the tops of the pistons if I run into a bad "pinging" situation from bad fuel. As far as the coating on the skirts, anything you can do to reduce parasitic drag is an improvement and HP gain. These may only yield marginal improvements or maybe none at all other than slight protection of the pistons whether they "need" it or not. I know a lot of the high performance guys are into the coatings and like you say, maybe its intended purpose is for the aluminum head guys. But also like I mentioned, the Nailhead can use all the help it can get and I want to gain any edge I can within reason. Once I start doing head work and get a set where I want them, I would like into coating them as well. To again keep the heat in the cylinders.

    I have a goal set for this car. I want it to run 12's in street trim and still be a cruiser. Not sure how completely achievable that is, but it's my goal none the less. Going to get it back together, on the road, see how she does, and then go from there. So any small advantage I can use, I am going to take it. Within reason of course.
     
  7. telriv

    telriv Well-Known Member

    Just a FYI. The top ring land has gone from a stock of .200" to .300". What this does is help ward off detonation for those with little or NO tuning skills. Along with the small groove above the 1st. ring on the top land to help with getting the combustion process to help push out behind the 1st. ring for a better seal.
    If I were you Johnny I would call Race Tec & ask questions 1st.
    Just my thoughts.


    Tom T.
     
  8. wkillgs

    wkillgs Gold Level Contributor

    You are obviously influenced by your uncle! I remember him telling me about his build at the GS Nats a 'few' years ago!
     
  9. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Hey Walt! Yes you would be correct, I am just slightly influenced by him. We missed you at the Nats this year, we finally made it up. And we are already getting a plan together for next year. The Cream car and Team Nailhead will return next year for sure.
     
  10. telriv

    telriv Well-Known Member

    Things that were the "Norm" in the past sometimes don't hold up to today's technology or materials. We have the knowledge today that wasn't available "Way back when". To get to where we are today "Someone" had to think "Outside" the box somewhere along the way.
    Johnny, it's your car & your $$$$ so do as you wish, but I would ask questions. One of my favorite sayings, "No one died & left anyone else God". We LL have our own opinions. That's what makes the world go round so to say.


    Tom T.
     
  11. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Oh I totally get where you are coming from and not ignoring you at all. Ill be sure to call and ask the questions Monday. I definitely do not necessarily know the best way to do things. I rely on the knowledge of all that have been in the game for years and been there and done it. Believe me I am taking in all opinions and suggestions. Tom both you and my Uncle have been there and done it and in different ways. At one time Donny was the fastest so he was obviously doing it right back then. You built the engine in Bob's car so no question you know your stuff and can jam some gears to boot. I would love to sit down and compare notes and numbers between what you accomplished with Bobs car and where Donny was when he stopped racing in the early 90s. We have a new setup started in his car as well and eager to see where we can take it. I am kinda following in his footsteps. I cant afford a race car and a cruiser, so im trying to do a combo of both which is why I am being so selective and taking it all in.
     
  12. telriv

    telriv Well-Known Member

    I TRULY wish you the BEST Johnny. Let us know how the discussion goes & the recommendations.


    Tom T.
     
  13. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Just to follow up. I did talk to RaceTec about the coatings. They said on pistons like these with the material they are made from, they don't really recommend the coatings because they don't believe you will see much benefit since it isn't being setup for an all out race engine. Now he did say for high HP race engines that they do look at those pistons on a case by case basis and determine if they believe the coatings will help or not. This is just the info I received from Tim, the guy that answered the phone. I don't know what position he holds or his level of knowledge. But when I asked about piston coatings this is the response I was given, so I thought I would pass it on. What I took from the conversation was that it sounded almost inconclusive. And what I mean by that is, they believe you won't see enough benefit to justify the cost of coating them. And that's fair enough. And if I were building a SBC, that would be all I needed to hear.

    However, I am building a Nailhead. And the one thing I learned both through my Uncle and the many threads on this board, is that a Nailhead needs all the help it can get. I had already figured the coatings into my budget(or lack there of) and so, I am having them coated anyway. :TU: I honestly feel like there is some benefit to these coatings. I obviously will never really know one way or another because I have nothing to compare to, but I am going with my gut on this one. Hopefully it's not just the mexican food I had for lunch.

    I appreciate RaceTec's position and honesty. I also appreciate Tom's input and trying to watch out for me, my build, and my bank account. Thanks again Tom!
     
  14. telriv

    telriv Well-Known Member

    Your WELCOME Johnny!!!! I, like many others have their own opinions. Sometimes gut feeling is the way to go. You'll never know if you don't try. That's what makes this "Hobby" fun.
    Good luck with your endeavors Johnny!!!!! I hope EVERYTHING works out to your satisfaction.


    Tom T.
     
  15. Brian Albrecht

    Brian Albrecht Gold Level Monkey

    Glad to see you went route '66! Neat ole ride...
     
  16. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Thanks Brian. It's just something about this car, I have been drawn to it ever since I saw my first one 15 years ago.
     
  17. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    So I got my pistons back from the coater. Those guys work quick. Said it would be 3-4 days and they were done in 2. They look good! I think these will definitely get the job done. Now I just gotta start saving and keep an eye out for when roller rockers are back on the market. Not necessarily in my immediate future, but definitely in the plan.

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  18. wkillgs

    wkillgs Gold Level Contributor

    Hey Johnny, any updates?
    Those pistons are gorgeous! Curious what you will be using for bearings, NOS or something new. And which other parts you're going with.

    I need to get back to the rebuild on the 401 for my red GS. Car has a rebuilt spare 401 in there now and I want to get the original engine back in.
    The whole 'numbers matching' deal sure makes swapping engines a headache. Even my blue '66 has the original engine apart and a built 425 in there now.
    I recently scored a set of .030 over forged TRW's. Thinking the skirt coating would be a good idea for those.
     
  19. telriv

    telriv Well-Known Member

    The problem with those pistons is they RAISED the pin hole by, I believe, .005" which puts them even further into the hole. I did an engine just a coupe yrs. ago where was found the same & we had to deck the block .030" to get the compression anywhere near 10-1 & change valves to flat faced from tulip to lessen combustion chamber cc's. the tulip accounts for between 3.7-4.0 cc's
     
  20. wkillgs

    wkillgs Gold Level Contributor

    Tom, do you know offhand what the piston-bore clearance should be for the forged TRW's? I found conflicting info online so far.
    I got these for less than what a set of cast pistons would cost, so some extra machining cost is fine. They'll likely need flycutting for v-p clearance too.....had to do that for my blue car's 425 when it was built a few decades ago.

    I have 4 401's I want to rebuild in the coming years. Some will be near stock builds, and some will be higher performance.
    The custom-sized forged AutoTec pistons are still the best available. I'll be getting some for a few of my builds.

    Hey Johnny.... if you want another Astro blue '66 GS, there's one in Cleveland. Looks like a decent car.
    http://cleveland.craigslist.org/cto/5353204918.html
     

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