Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: BBC stock heads

  1. #1
    Member JOURNEYMAN
    Join Date
    May 2007
    Location
    San Dog
    Posts
    34

    BBC stock heads

    I have a pair of 3904390 early ovals with 2.19/1.88 valves. Searched here and the net for flow numbers and can't find them, anyone know? Also what would be a guesstimated fair price, these are fresh rebuilds.
    "Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf."

  2. #2
    Senior Member DYNO OPERATOR
    Join Date
    Feb 2006
    Location
    VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
    Posts
    540
    I am not familiar with those. I am pretty cetain though that Chevy never put those valve sizes in an oval head.

    Can you post combustion chamber pics? Also maybe intake port pics?

    Ed
    " Let all things that hath breath, praise the Lord. Praise Ye the Lord" Psalms 150 vs 6.

  3. #3
    Senior Member RACING JUNKIE
    Join Date
    May 2006
    Posts
    2,044
    This is what I come up with on mortec
    oval..CLOSED..396, 427, 98cc chamber
    I had a simialr head on my 468 but with the stock 206 valves, obviously someone has cut the seats on your heads to the bigger 2.19 trouble is unless the vavles pockets were unshrouded and bowlhogged the bigger vavles wont make much difference.
    These haeds worked great for me with the smaller cumbustion chamber it helped bump my compression up with a small domed pistons, they were all torque, pulling hard from idle to where I was shifting @ 5500
    Goodluck Charles
    ***IN GOD WE TRUST***

  4. #4
    Member JOURNEYMAN
    Join Date
    May 2007
    Location
    San Dog
    Posts
    34
    Yes the valves were added, I don't see any bowl work. I know they were off hydraulic cammed 396 and 427 but can't find a lick of info about flow capabilities. Thanks, I'm figuring they are a good match to the Eddy torker cam and manifold.
    "Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf."

  5. #5
    Member JOURNEYMAN
    Join Date
    May 2007
    Location
    San Dog
    Posts
    34
    I have a question for the more experienced guys, should I run 260cc oval ports that give 11:1 and a 262 @ .050 cam(inspired by ed's chevelle) or AFR 315 that give 9.5:1 and a 242 @ .050. Both are solid rollers and the dynamic compression is within .02 of each other, will use 200hp NOS and 1050 Dominator on 439 with forged pistons. I wasn't going to build this engine until I pulled it apart and found a really good base. The AFR will put out 600hp NA but cost me a bit more in the extras, i.e. push rods, gaskets and so on. This is the same Chevelle I asked about earlier but no longer using the GMPP heads.
    "Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf."

  6. #6
    Senior Member DYNO OPERATOR
    Join Date
    Feb 2006
    Location
    VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
    Posts
    540
    242 roller will be like a little puppy dog in the BB Chevy. It will idle fairly smooth.

    The 262 would be much stronger and would really be good with those 315 AFR's or a set of the Canfields. Less mney I think.

    My cam in my old Chevelle in the last engine, which is the one I talk about becuase it had the oval 781 heads was not a roller. It was a cheap cam I got used that was recommended for either oval track or for ski boat. It pulled that 4,000 + lb Chevelle boat pretty well.

    I do have a guy out there now driving on the street now with a 454 type engine and a Comp Cams Nitrous Cam of some healthy duration ( I think 250's and 260's) that is a hydraulic and not roller with a little over .600 lift and it is a bear with not much idle vacuum and sounds bad to the bone with it's 10.90 -1 compression. That is also another 4 speed car though.

    If there is any way you can do your 11.00 -1 compression and get AFR, Canfield, etc alum heads and a cam like the 262 dur @ .050 it would wake up the beast. With nitrous it would really be bad.

    Ed
    " Let all things that hath breath, praise the Lord. Praise Ye the Lord" Psalms 150 vs 6.

  7. #7
    Member JOURNEYMAN
    Join Date
    May 2007
    Location
    San Dog
    Posts
    34
    The shortblock is already built. It was supposed to be a 9.5:1 and hyper piston stocker but got a nice surprise. In this situation it is either or, I have everything for the 11:1 but a couple bills to acquire the incidentals for the AFR heads.


    I have decided to use the 262 and iron heads. That roller cam has the same LSA and duration at .015 of only 6* more intake than the old l-78 cam. But the duration at .050 is 20* more, so my train of thought is that this will make up the lack of flow compared to the square ports originally used. Ok, I know this is all theoretical anyway BUT using flow of the square ports and the original cam comparing the difference of the ovals gave me a requirement of 262* @ .050. I had no idea that a roller cam can make that much difference, making a huge cam look much smaller to the engine. If I'm all screwed up in my thinking someone please correct me, but it sounds good on paper.
    "Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf."

  8. #8
    Member MASTER JOURNEYMAN
    Join Date
    Apr 2003
    Location
    Fenton MI
    Posts
    38
    Why not just order the AFR's cut down to where you need them?

    Adam

  9. #9
    Member JOURNEYMAN
    Join Date
    May 2007
    Location
    San Dog
    Posts
    34
    I already have the AFR cut to 114 but to install them I have a nice shopping list left for pushrods, intake, cam and everything else. I have all the other stuff on hand and it is just cheaper to do and with a week old newborn fun money is short.
    "Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf."

  10. #10
    Senior Member DYNO OPERATOR
    Join Date
    Feb 2006
    Location
    VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
    Posts
    540
    I had no idea that a roller cam can make that much difference, making a huge cam look much smaller to the engine. If I'm all screwed up in my thinking someone please correct me, but it sounds good on paper.
    lol
    Works good in real life too.

    A roller with same numbers will give you a whole lot more rate per degree of rotation and under the curve than you can possibly get with a flat or hyd flat lifter. The actual engine will behave like it has maybe 10 degree less duration at .050 as far as idle traits go. You can also give it a little wider lobe separation and the idle gets smoother and the idle vacuum increases too.

    Ed
    " Let all things that hath breath, praise the Lord. Praise Ye the Lord" Psalms 150 vs 6.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Email us - Support@RacingJunk.com
Call us - 866.326.9227
Copyright © 2005-2016 RacingJunk.com All Rights Reserved.

Designated trademarks and brands are the property of their respective owners. Use of this Web site constitutes acceptance of the RacingJunk.com
Terms of Use, Classifieds Disclaimer, Privacy Policy, and Cookie Policy