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318 Poly dragster engine

Discussion in 'The Hokey Ass Message Board' started by Dolmetsch, Jul 21, 2012.

  1. Using a reamer I bought many years ago that was designed for aircraft manufacturing here in Canada during WWII I rough finished the pin bores. It is a barrel shaped reamer so makes a nice hole even if you dont start off perfect. I took them all within about .002" to.0015". I could have done it all on the hone. .009" doesnt seem like much but when you are shaving that much off it gets awful boring. Normally pistons get no more then a quick rub to free up a stiff pin. Some guys get upset if you are using up their stones for no good reason. Since I am a guest in his shop it would not be polite to use up his wearables unnecesarily. Since I had the reamer I decided to save my back and get them close. Then went down to my pals shop. He just pointed to the sunnen pin hone so I went right at it. Found a manderal that would work and removed his and installed it. It went very well. All done now. Fit for "dropthrough" for those of you old enuf to remember that method of fit.
    I had forgotten how hard running the hone is on my back. Standing on mostly one foot and pushing and pulling. His machine is a lot bigger then mine was and more modern but the tray is about 1/2 again as large. That coupled with too many lunches and the new style manderals which are shorter made for a break between each pair of pistons to cool down and catch my breath. But it is all done now. Nice of him to give me such free access to his shop. He is the fellow who taught me the auto machine trade. Anyway I owe him a big thanks. Next I have to resize the rods with new HD bolts then balance it all. I am actually enjoying this old school build.
    I would have to look it up but it seems to me when I put the Chev 6 pistons in the slant six the pin diameter change was the same.
    Don
     

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    Last edited: Jul 30, 2012
  2. In fact back in the day when we ran a 300 ford in my pals (same guy's shop I used for this) he (Harry ) ran 12.5 pistons for the 302 cu in Z28 motor in the Ford six. Seems to me that Chev and Ford pins were the same diameter but I would have to look that up to be sure.
    Re that swap. He eventually had to remove a bit of dome from the Chevy pistons as Compression was a wee bit over the top.
    Don
     
  3. ??????????? I am still scratching my head everytime I see this post.
    No it is not a hemi. So what? I must have missed something.
    Don
     
  4. George
    Joined: Jan 1, 2005
    Posts: 7,724

    George
    Member

    Guy was trying to say the Poly is almost a Hemi & TR was disagreeing with the observation. I agree with T R, not a hemi, not close.
     
  5. OK , I thought that was obvious.
    Don
     
  6. TR Waters
    Joined: Nov 18, 2006
    Posts: 1,439

    TR Waters
    Member
    from Vermont
    1. Early Hemi Tech

    Yes, my point was that the head is not a hemi head with the exhaust valve moved. A better comparison would be to a Ford Cleveland style head, with the exception of the small valve and port sizes. There is no doubt that you can make these heads perform for your intended purpose.
     
  7. George
    Joined: Jan 1, 2005
    Posts: 7,724

    George
    Member

    Some have stated that the Poly inspired the BBChevy head & when Bunkie Knudsen went to Ford, the GM guys he brought over used the BBC to influence the Cleveland family.
     
  8. Rusty O'Toole
    Joined: Sep 17, 2006
    Posts: 9,657

    Rusty O'Toole
    Member

    It's NOT a hemi it's a poly. The poly resembles a hemi more than it resembles a wedge. If you took the exhaust valve and moved it over, opposite the intake, and put it at an angle, it would be a hemi. It is supposed to be a compromise, not a full blown hemi but with some of the advantages of a hemi.

    Hope this is clear.
     
  9. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,661

    Truckedup
    Member

    W engines had a short but decent racing history from the introduction in 58 till the end in 64 ,here;s a few of the wins against the best there was at that time.This short list of documented wins does not include thousands of wins at local tracks.

    1960... Junior Johnson wins the Daytona 500

    1960... Rex White was the NASCAR Champion driving his 1960 348 Chevrolet Bel Airs

    1961... Bill Patterson was the NHRA A Stock class Champion at the '61 Winternationals with his 348 1960 Impala.

    1961... Ned Jarrett wins the Nascar Championship

    1961... Frank Saunders wins Super Stock at the Winternationals

    1961... Don Nicholson wins Stock Eliminator at the Winternationals

    1962... Don Nicholson wins Stock Eliminator at the Winternationals again

    1962... Hayden Proffitt wins Stock Eliminator at Indianapolis

    1962... Dave Strickler wins SS/S at the US Nationals

    1962... Winternationals B/Stock Terry Prince 60 348

    1963... Winternationals A/Stock Strickler/Jenkins 62 409

    1963... Winternationals L/P Franks Sanders 63 Z-11

    1963... Winternationals B/FX Dick Harrell 62 409 w/z-11 top

    1963... AHRA Winternat. S/S Dick Harrell 63 Z-11

    1963... Summernationals A/FX & Strickler/Jenkins 63 Z-11
    Little Eliminator
     
  10. I see there are still a few "rippleblock" fans out there.
    Don
     
  11. I balanced the pistons today. Very minor required. Had to machine one. The rest were brought in spec by swapping pins around. Yeah I know I should make all the pins the same and all the pistons the same however unfortunately or fortunately the motor doesnt know the difference. Weights are + or - a gram with final for piston with pin being pegged at 802 grams. Highest being 803 and lowest being 801.
    Next I have to resize the rods with new HD rod bolts then balance them . I will write down all the figures and then send the crank out for balance. I DO NOT send the flex plate as too many shops use it for a quick balance , then should I break one I instantly have an unbalanced engine once I replace it. I will send gear, crank, key, and vibration damper and all my weights. 1 Piston, Pin, ring set, rod small end weight and rod big end weight along with weight of 1 rod bearing. They will take it from there. I have settled on peak power at 7000 to reach my goals. So now I have to think about a cam. Need a good chunk of duration to achieve this. And to run too much duration with my compession ratio is trcky too. Going to hae to get creative. Maybe talk to my cam grinding friends and see what masters they have. No new cores anymore for these motors so it is regrind only. Lift probably will wind up in the .575 range which is a bit low when you subtract valve lash. Anyway the hunt is on. What would I like if I could have anything? My intial gut instinct 276 duration at .050 with .600 lift at at zero lash. And that with Mopar ramps (.904 lifter diameter) We shall see what we find. There are occasionally old serious cams turning up for these engines. I know my old friend G Palovich (Mr Poly) comes up with them now and then. In fact I emailed him but he must have changed his email. No response. Usually he phones. He has a lot of this stuff coming and going all the time.
    Don
     
    Last edited: Aug 5, 2012
  12. BigBlockMopar
    Joined: Feb 4, 2006
    Posts: 1,361

    BigBlockMopar
    Member

    Cool engine-project Don!
    Can't wait to hear it's first startup.
     
  13. Hi there old friend!
    Just got back from your wonderful land. Glad to see you are still kicking.
    Yes This is a very interesting project. What I find most interesting is how it seems to be almost falling together. Like the balance just now today. Inspite of machiningg the pistons after cutting the register point when I went to balance them I only had to machine one of the eight to get them all in balance. Never ever had that happen before with a set of reworked pistons.
    I have a trans and converter here so when I get it done I may just bolt it back up and light it up on the floor. Just to hear it burble. If I do I will record it. Head work will be the big chore. I am following a similar porting technique I used on my Slantsix head. I like the results I got there so I will see how the poly heads like it. What are U working on these days?
    Don
     
    Last edited: Aug 3, 2012
  14. Waiting for the rod bolts so I can get to resizing then balancing. In between I have been helping a friend with project that is coming along very well. Hopefully the bolts come early this week. I would really like to get the rotating assembly balanced and installed this month.
    Don
     
  15. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,661

    Truckedup
    Member

    I like your approach to these less commonly used engines. You can get nearly .570 lift on a regrind? Must have big lobes?
     
  16. That thing is completely bitchin! I am doing some similar stuff to Nailheads trying to squeeze more power out of it. What is the target number for your head flow? What size intake valve?
     
  17. BigBlockMopar
    Joined: Feb 4, 2006
    Posts: 1,361

    BigBlockMopar
    Member

    I'm currently battling a bit with the tune of the now roller cammed, longrammed stroker in my '60-NY.
    Timing advance, engine heat, midrange cylinder pressure and underhood temps are killing the tune of the motor. Considering of putting louvers in the hood.
    But at least it has a cool lopey idle now!

    Last saturday I did a 3-hour drive each way from Holland to Germany and 3 hours back again with this 496" powered car. I saw the inside of a gasstation 3 times that day. Car did just under 12mpg. Need to work the carbs on the 'cruise'-tune a bit more.
    In the mean time my wallet is on life-support ;)
     
  18. When regrinding material is removed from the bottom or heel of the cam not added to the top of the lobes.Also lobe lift is consderably less then valve lift so lobe lift would be less then .400 even then. Most cams hot or cool (or even down right cold) are the same height in the lobes. Never larger then the cam bearing journal otherwise it is hard or imossible to install them. I have had reginds for many cams over the years and have a fellow I have worked with in T.O. who has always done them for me and even made a master for me. Cam cores are all made in one or two factories regardless of their intended use. Cam regrinding is a most misunderstood deal. In truth there is little difference in the finished product except the used core sometimes has more experience. I have not had any problems in 40 odd years personally with regrinds. Doesnt mean i wont but so far so good. I will ask for the grind I want from their library and he will tell me if he an or cant do it. We have worked this way so long now we have established a trust. Almost all cam companies BTW offer a regrind service. With this engine and now no new cores available I have no choice unless someone has one from days gone by they would sell me. In this engine i have to use everything I can to get to or even close to my goal. Camshaft is the heart and soul of the project.
    Don
     
    Last edited: Aug 7, 2012
  19. Intake 1.94 with .312 stem. I need at least 200 cfm to feed this motor at 7000 for 100%. I am hoping to get about 225 cfm if all goes well so 100% VE will be available before max lift point but will be there for max piston speed point or as close to that as possible. That occurs at somewhere between 70 and 80 Deg ATDC
    Don
     
  20. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,661

    Truckedup
    Member

    I asked about the lobe size because I had a few cams ground for GMC 302 inline using an NOS camshaft.Best lift was about .440 with duration around 215 at .050.I could see the lobe heel was just flat with the shaft of the cam with a 1.41 rocker ratio.This was street grind needing durability,maybe a race only is different.
     
  21. RichFox
    Joined: Dec 3, 2006
    Posts: 10,020

    RichFox
    Member Emeritus

    No, that is about right for a reground GMC. When I was running my 270 you could still get new cores made for big lift/long duration. When I built the Packard V8 for my Vega I was able to find a Isky 505C to have reground. The original lobes were much to small to get much lift or duration with out almost grinding through the cam shaft at the heel. When I built my Plymouth engine Dema Elgin welded the lobes for a larger envlope. I then bought two blanks from Joe Panak at RotoFaz to go even bigger. If I wanted to go bigger yet I would have had to bore the can holes in the block. It was already running on iron so I couldn't remove the bearings to gain more room
     
  22. Oh I see. I havent ever done a 302 Jimmy so you have a leg up on me there. . We have undercut the core if nescesary. Often even aftermarket cam companies when you get theirs are often undercut as well. Most common grind i have used on the 318 poly is the 340 1968 stick grind. However I need a lot more for this one. I have had slant sixes reground for .550 lift and am currently running more then that in my 6 cyl Rail's engine but that is a new core. I have had early hemis reground to .550" with no trouble. I have had a 1600 colt cam reground for .600. But to be perfectly honest I dont know if this core will take it or not. I will have to see what John says. I will phone him first. I wish I had my own grinder. There is so much I would like to try. Anyway when I find out if it is practical I will report back. Anyway I guess till I talk to John and send him the core I am just blowin smoke. We shall see.
    Don
     
  23. Yes I have burnt thru $82 fuel this week so far or just about in my Max Wedge. But then it is summer . 12MPG ? Could be a lot worse. Sounds like you are still having fun. That is a long drive for a motor like that . Anyway i know you will get it the way you want it. Rome wasnt built in one day . Everything takes a bit of time.
    Don
     
  24. RichFox
    Joined: Dec 3, 2006
    Posts: 10,020

    RichFox
    Member Emeritus

    I don't really like to have the lobe circle reduced to much. The lifter drops down and on some engines (the Packard V8 for one) the lifter bosses are pretty flimsy and unsupported. As far as the GMC goes you might check with Don Ferguson at Paramont Forge about a new race core. My current Dodge Bros. has nice mushrom lifters in drop in bosses. Base circle looks like they were planning on .700 lift flatheads as soon as springs became available. To bad Chrysler didn't pick up on that feature when they took over Dodge.
     
  25. I have been wondering speaking of Mopar flatheads and such has anyone had one of these deals on a flow bench? I admire you folks who do this type of hot rodding. Making everything is always fun. How do I decide how much the core can be reduced? # 1 I will without hesitation reduce it till it is smooth and not rough cast. It is my belief that there are no strength issues there for sure and it may on fact be stronger as no ragged spots for a crack to start. In many cases that will give enuf of an increased base circle to do anything I want. Beyond that I compare with other cams to see what their basic shaft size is. If they are similar length then i personaly take it that is a reasonable diameter and materials dont really vary all that nuch I believe between manufacturers. And sometimes if it my own project and I am prototyping I may go out on a limb to see what works. In that case I ask no one but venture out on my own. It lives or dies on strickly its own merit. Having said that sometimes I am surprised how well some of these adventures turn out. Have had a lot more thumbs ups then thumbs down. Maybe just lucky. Who knows? My dad who was an successful aircraft radio design engineer when that was going through its big development changes used to tell me when I was young and when I would say "I dont think that will work", he would say to me "Well Don , one thing we can be sure of. If you dont ever try it , it wont work." It used to make me mad back then but I find now on projects like this it is words to live by. When you are playing on your own and a customer is not in the mix you can push the envelope as much as you like. All you have to lose is a bit of time and a few bucks. More often then not you have everything to gain. I think that is what I like about working on these oddball or less poplular engines. Because so little is made for them you cant spend a lot of gold. You have to make almost everything or talk someone into making it for you. I find this fun and interesting. Obviously reading down the list of stuff you have tried, you do to.
    Don
     
    Last edited: Aug 8, 2012
  26. I like your piston holder. I do have a wonder. Would it have made any difference to do something simular and mount it in a mill and trim only the surface that hit the cylinder head making a small popup. Also isn't there a forged pist available? I know you said low cost is important. I've used pistons out of the scrap at our local machine shop when I kived in west Texas so I understand. Just asking. Like the attitude.
     
  27. RichFox
    Joined: Dec 3, 2006
    Posts: 10,020

    RichFox
    Member Emeritus

    My dad was a radio experimenter also and did a lot of radar and sonar work for the Navy. Like you, I just go by eye. We will never be famous, but it seems to work for us.
     
  28. Happy is what counts. Fame is fleeting.
    I do all and I do mean all my protyping with so called cast pistons. Yes you can buy forged. Probably around $700 plus shipping . So make it almost $800. And what difference would it make. ABSOLUTLY nothing. Also you would have to find someone who would make you exactly what you want. That is a huge obstacle. Much easier to make your own from casting with enuf meat. I have run cast pistons in many many experiments and eventualy replaced them at some point but to be honest never broke even one.
    My current slant rail has them My 460 from a 400 ($1500 econo big block , July 97 Chrysler Power Magazine) ran for several years on the original cast pistons. In fact we still have them.
    Built some 6 cyl chevies wih 307 pistons . None of them ever gave trouble. All still running well.
    Built a 300 ford with 390 cast pistons. They are still around and may wind up in another engine as they are still perfect. I could go on but I wont. Bottom line is any piston fit right(NOT tight) and used in a reasonable RPM range will last. Say for instance 7000 or less.
    I have a mill and I thought about it but looking at the shape of the combustion chamber the amount I would have left not machined (would have been only about 20%) and then I have to put a valve relief there anyway I choose this method. It might not be the absolute best but it was practical. Compression will be well above stock. Piston even with reduced crown is still well above minimum specified for this type of piston so there should be no worries about top ring land failure. I think they listed wholesale to me about $12 each and my pal wouldnt let me pay anyway so ??? I am hoping the $800 I would have spent for forged will cover the whole short block build completely. Not that I believe cheap is better. I just know this will do what I want without problems and dont really have a lot of cash for projects anyway. Just do what I can with what I can afford. I have been accused far more of Cheating then Cheaping. How you cheat at bracket racing or run what ya brung is beyond my understanding. I gusee if you spent ten grand and got whopped by a $1200 motor that could cause one to mispeak. ;>) However Mostly I do this for fun now.
    Having said all that I would be lying if I said it does not thrill me to beat mega buck competitors running motors costing only a few 100 to a few 1000 dollars. It has made for me an interesting career.
    Don
     
    Last edited: Aug 8, 2012
  29. Do you feel lightweight pistons or pistons with narrower rings would be of benefit in your Poly?
     
  30. I believe strongly that the lightweight thing is overdone big time. Other than lightening the load on the con rod and these are more then strong enuf for what I am doing I do not believe in the current light weight thinking. (revs quicker etc. ) I believe that the weight of the crank and the pistons of reasonable (IE like stock)mass is the last thing stopping the engine from reving faster. The biggest obstacle is the car it is trying to move. Making it lighter will always pay you back. Making the pistons lighter , I seriously question that except in extreme cases. And here I am talking for example traditional hot rod engines that never would see over 7000 RPM if that. I have had customers who wanted to go down that road after we built something basic and got it working. (I call this campfire disease cause it around the campfire with the $$ guys that they get these ideas.) I obliged but have yet to see an ET change from it. I didnt mind going to the forged piston and I didnt mind that it was lighter as it gives the rods and bearing a breather if it is a hi RPM engine but actual power? I doubt it.
    I prefer the thin rings but have built so many engines with the wide ones that were successful I can go either way. I use one brand of rings in most engines and like their low tension version for race only stuff. I have also used Total Seals since they were first introduced,(back when you got a free Total Seal candy in each box) in appplications where I thought they would be of benifit. I have rethought this a bit over the years. Have some ideas on the subject but still not carved in stone yet.
    Don
     

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