Register now to get rid of these ads!
  1. Hey fellas, just in case you missed it - The Rodder's Journal and The Jalopy Journal is celebrating 20 years of bringing you traditional hot rods and customs by offering you a one-year subscription to TRJ and a H.A.M.B. Alliance membership for only $75. Click here for details.

350 piston in a 327?

Discussion in 'The Hokey Ass Message Board' started by gasser32pickup, Jan 14, 2009.

  1. gasser32pickup
    Joined:
    May 20, 2008
    Posts:
    36
    Location:
    Australia

    gasser32pickup Member

    Trying to find a suitable set of pistons for my little 327 combo.

    63 vintage 327 block, current virgin bore, most likely to be bored to 0.030".

    Stock ground 0.010 327 steel forged crank, 5.7" SJ H beams.

    63cc 462 Fuelly heads with 1.94" and 1.60" valves, bowl and short turn ported and deshrouded inlet valve.

    Chasing 8.5:1 or less compression to suit my vintage 6/71 GM blower running 10psi. Topped with a modded 850dp, covered by a garlits Enderle type scoop. Should look bitchen and make solid 450+hp

    Trouble is, low comp 327 forgies are really thin on the ground here in Australia, and even hard to find online. So I was wondering if I could run a 350 type Hi-Comp or flat top piston, and mayber deck the block 0.050".

    Anyone tried a 350 piston in a 327?

    I think I can make it work at the top of the bore, but worried about the piston falling out at the bottom of the bore or hitting the crank.

    Anyone...? Anyone...? Stories? Failures? Sucesses?
  2. CNC-Dude
    Joined:
    Nov 23, 2007
    Posts:
    529
    Location:
    Ringgold,Ga.

    CNC-Dude Member

    The difference in compression height between these two engines is over .100, so decking the block .050 still leaves you with too much deck height to give you any realistic compression. Trying to find pistons for these older engines used is getting harder all the time. I can just imagine your problems in Oz. You can always step up to the pump and order from Jegs or Summit as an alternative.....
  3. gasser32pickup
    Joined:
    May 20, 2008
    Posts:
    36
    Location:
    Australia

    gasser32pickup Member

    My compression calculator says with a -4cc piston, 0.100" down the hole, 8.0:1, so with a small lump, 8.2:1 could work out not too bad for comp.

    I can get a set that works, out of Summit for around $850ish. But i dunno, my locally available hardcore 383 pistons are barely half that, weigh less and are a heap stronger, so I guess its the stubborn arse in me that wont open my wallet that far yet, for just a piston.
  4. Devin
    Joined:
    Dec 28, 2004
    Posts:
    1,477
    Location:
    Napa, CA

    Devin Member

    check out PAW, I'd bet they have 327 pistons for a reasonable sum.
    Register now to get rid of these ads!

  5. bobss396
    Joined:
    Aug 27, 2008
    Posts:
    4,763
    Location:
    Long Island, NY

    bobss396 Member

    I'd look in a Chevy dealer parts catalog, people laugh, but they carry a load of good performance parts at the right price most of the time.

    Bob
  6. BillBallingerSr
    Joined:
    Dec 20, 2007
    Posts:
    651
    Location:
    In Hell

    BillBallingerSr Member

    Using a 327 dished piston with a big chambered head is better. It will ping like a popcorn popper that far down in the hole. Try to keep it coming up within .010 of zero deck and use a .030 gasket. With a big chambered head and a dished piston you should be down in the low 8:1 range. KB makes a dished 327 piston. The blower is going to make up for the "lesser" heads.

    If you aren't running more than 3-4 lbs of boost, a Chevy cast piston will live with good gas and a tight quench. All cast pistons are not created equal though. The factory ones have steel reinforcing struts that alot of "rebuilders" don't. I wouldn't doubt that GMPP still stocks the dished 327 cast truck piston. The 327 needs popups to get over 10:1 as it was with 63cc heads. A flat top motor wasn't but barely 9:1.
    Last edited: Jan 15, 2009
  7. Shifty Shifterton
    Joined:
    Oct 1, 2006
    Posts:
    4,973
    Location:
    Central Iowa

    Shifty Shifterton Member

    Are you hung up on using the old heads?

    Buy aftermarket heads with larger chambers and even better runners. Use cheaper pistons. Sell old heads to offset cost. End up running harder and spending less.

    Better heads would also let ya turn down the boost and get equivalent power, thus being nicer to parts and easier to tune & find fuel

    good luck
  8. Pir8Darryl
    Joined:
    Jan 9, 2008
    Posts:
    2,496
    Location:
    Louisville Ky.

    Pir8Darryl Member

    Like BillBallingerSr said, mis-matching components like that is just going to open up a big 'ole can of worms that will cause more headaches than anything.

    Droping the slug that far down the hole will cause the piston to loose it's quench. You will also loose swirl causing un-even burn which will cause serious carbon buildup,,, resulting in hot spots and ping.

    I understand where your trying to go here, but if the 327 pistons are seriously that much of a problem for you, it might not be too bad of an idea to moth-ball your vintage motor and buy/build a belly-button 350 with cheaper off the shelf parts.
  9. BillBallingerSr
    Joined:
    Dec 20, 2007
    Posts:
    651
    Location:
    In Hell

    BillBallingerSr Member

    AFR or World Sr's in the 200-210 port range would be good, I haven't looked in awhile, but I think they offer a 72-74cc head. Much better solution. Someone with a '63 Vette would like to have those heads, I bet it would probably wash all said and done.
  10. motor mikey
    Joined:
    Jul 17, 2002
    Posts:
    261
    Location:
    hanover pa

    motor mikey Member

    I checked my speed-pro catalog and they make a 327 blower piston that is forged. Only problem is that it uses a 5.80 rod. Also could use a 5.85 rod will work with either. should put you around 8-1 cr.
  11. Shifty Shifterton
    Joined:
    Oct 1, 2006
    Posts:
    4,973
    Location:
    Central Iowa

    Shifty Shifterton Member

    The reason it uses a 5.8 rod is it's a 350 piston designed around a 5.7 rod. Sounds like the same piston he's asking about, more or less
  12. mustang9093
    Joined:
    Dec 23, 2008
    Posts:
    86
    Location:
    Indiana

    mustang9093 Member

    Contact www.wiseco.com. Tell the customer service rep. exactly what parts you have and what you intend to use the engine for and they can make exactly what you need. You already have a steel crank and aftermarket rods so the custom pistons are all that you need. They might have a shelf piston that is ready to ship.
  13. BillBallingerSr
    Joined:
    Dec 20, 2007
    Posts:
    651
    Location:
    In Hell

    BillBallingerSr Member

    Speed -Pro pistons are made in India now, and they are junk. Last set of new Speed-Pros my nephew got for a customer project, he said they looked like they had been machined by an 8 year old with a machete, chattermarks, the pin boss wasn't even straight. Mocked it up with one and it was .002 crooked front to rear on the pin axis. They use KBs nowfor mild builds, Ross or Wiseco for the high end stuff.
  14. Von Rigg Fink
    Joined:
    Jun 11, 2007
    Posts:
    13,436
    Location:
    Garage

    Von Rigg Fink Member

    wow i had no idea that 327 pistons were so hard to find...
    Ive got 16 of them
    8 of them are in use:cool:
    but the other 8 are K.B. Hypereutectic Pistons still in the box:D:cool:

    probably more than 10 years old and never been used
  15. paulweldit
    Joined:
    Jul 10, 2005
    Posts:
    657
    Location:
    Hurst,Texas (west of Dallas & east of Ft.Worth)

    paulweldit Member

    Use a Forged 350 Flat top piston . Been there, done that, many times.Be sure the piston uses the stock ring groove.
    I know it's hard for you guys out of the country to get parts but the blower will like a set of 202 valves. Try to stay with a long duration cam but mild /low lift cam. Isky makes some really nice SB blower cams.If you do decide to go with new pistons, "Probe" makes a reasonablly price piston for your application. Paul
  16. paulweldit
    Joined:
    Jul 10, 2005
    Posts:
    657
    Location:
    Hurst,Texas (west of Dallas & east of Ft.Worth)

    paulweldit Member

    Oh Yeah I forgot to say. I like to run 7.5 CR on my blown motors... it just makes them easier to tune. Paul
  17. Unkl Ian
    Joined:
    Mar 29, 2001
    Posts:
    12,038
    Location:
    Just past the corner of Hell and The Twilight Zone

    Unkl Ian Member


    Summitracing.com has 327 pistons.
  18. gasser32pickup
    Joined:
    May 20, 2008
    Posts:
    36
    Location:
    Australia

    gasser32pickup Member

    WOW.......

    Didnt think that many people would be interested.

    Pretty keen to keep my fuelly's, they are period and in really good nick. Cam is a fairly fat solid for a little motor, 242@0.050 110*centres. Actually, lobe centre might still be a little tight for the blower. Planning on running 10psi ish.

    Paul: Not quite sure, Have you run a 350 piston in a 327? Did it work?

    Definately want new pistons. I think I will just buy the dish top 327 forgies from summit, dont want to shell out for them, but I think it will save the headache later.

    Whats the probe piston? I dont have a probe catalogue handy.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2013 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.