correct hemi piston

Discussion in 'PSI Superchargers Tech Questions' started by mark6052, Jan 9, 2009.

  1. mark6052

    mark6052 Member

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    Im building a new engine. its an old JP1 block, with BAE fuel heads 180 chamber. I can get a good deal on JE pistons. problem is they only build for veney/bnr heads. they have a different comp height. 1.430 (arias)vs1.612. manufacture says they can be used with different rod length. am I getting into this combination wrong? looking at a set of veney heads vs mine I cant really see a difference. I dont want to build an oddball combination. is there really that much difference between bae and veney pistons shape.
     
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  2. jonimus333

    jonimus333 New Member

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    pistons

    I am not sure if the domes are different, But it seems alot of people get stuck on piston and rod lengths. You can make anything work with changing rod length, comp. height, and gasket thickness, as long as you don,t go too far. Long rod not bad to short of a rod too much side load etc. If the Manuf. says its ok. and the it doesn't make the rod too short. Save your money and go for it. Your not out there running Top Fuel. Just my Thoughts. Good luck Don
     
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  3. nitrowannabe

    nitrowannabe Member

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    Wait...I'm trying to get a good answer to your question from my engine builder. I'm doing a bae fuel head alcohol combo also.
     
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  4. john348

    john348 Top Alcohol

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    Mark

    I remember buying pistons from BAE for my veney fuel heads years ago
    maybe the old veney and brad fuel head/piston was the same
    maybe your best bet would be to call BAE to see what will work with your deal
    the newer veney/bnr stuff has a pinch camber
     
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  5. nitrowannabe

    nitrowannabe Member

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    From what I found out the veney/bnr has different valve location and a much higher compression height than what you would want in a bae fuel head.You would need a short rod and it would be difficult to get a 10.5 compression even then. You should be able to find a good deal on the proper piston for the bae fuel head . It's a very common low budget combo and works great.
     
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  6. DQUES

    DQUES Member

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    Arias has a good racer price on their pistons , around $70 a piece for the fuel head engines . BAE will tell you to call Arias for pistons because they do not stock them for the alcohol/fuel head combo .
     
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    Last edited: Jan 11, 2009
  7. mark6052

    mark6052 Member

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    its too bad that JE only makes one piston. I have not had the chance to look and compare the difference between the two. so much for a "good" it always bites ya.:) I will call BAE asap. and see what else I can learn. it does seem arias has an on the shelf piston. bme is all custom? or made at time of order. does anybody have a used veney piston I could get to look at? thanks.
     
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  8. nitrowannabe

    nitrowannabe Member

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    I know I have a Veney/Newberry piston somewhere and also a job # for the Arias/BAE fuel head pistons I am going to use.
     
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    Last edited: Jan 11, 2009
  9. nitrohawk

    nitrohawk New Member

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    When I first started running A-fuel I used the big chamber AJ fuel heads. No one had an off the shelf piston with the desired compression. What I did was put about 2.5 inches of bondo on top of an old piston put the head on using a few studs and turn the engine over to where the piston is coming up. Use a breaker bar on crank nut and put considerable pressure on the bondo so it will go into combustion chamber and conform to it. ( Be sure and grease the sleeve and head surface so bondo will not stick to it.) Send this to Arias and they will make you a set of pistons. When you get the pistons make you an adjustable rod by cutting a section out of an old one and using a left hand thread in one end and right hand thread in the other. Make a connecting bolt by welding a left hand bolt and right hand bolt together. Use a dowel with loose fit in one side to keep the rod from twisting when adjusted.
    Put one of your new pistons on this rod and with the head gsk you want adjust the rod height until you get the desired compression. I did this and it worked perfectly. Now measure the rod length.
    Find compression by turning engine to TDC use burette and put cc's in until fluid level is at the bottom of spark plug hole. Lets say it is 80cc. Then turn the engine to BDC and put cc's of fluid in until it once again is at the bottom of the spark plug hole. (Be sure motor is level)
    Add the combustion chamber volume to the amount that it took to fill the whole cylinder. Say 80 + 920= 1000 cc's total Divide 80 into 1000. The results woud be 12.5 which would be your exact mechanical compression.
    These numbers are only an example.
    I have an adjustable rod that I would loan you with a security deposit.
    Good luck
    Bob Holley
     
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  10. john348

    john348 Top Alcohol

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    mark
    sent you a PM

    what bore and stroke are you looking to use
     
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  11. rob s

    rob s s

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    Did u every figue
     
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  12. rob s

    rob s s

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    Did i ever figure out the pisyon
     
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  13. TADHemiracer

    TADHemiracer Member

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    As DQUES sid, Arias has on the shelf pistons pistons for the AJ fuel head. To get a lower compression, I use a shorter rod. If I remember correctly, they were about $70. If I wanted custom, one off, pistons, if I provided a sample, they would make them but would have been a substantial price increase. The compression height was around 1.42.
    Just my .02 worth.
     
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  14. Soldierboy0098

    Soldierboy0098 Active Member

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    I ordered custom pistons for a blown alky fuel head deal for a friend from Arias and they were like $550, only requirement was we had to slap a small Arias sticker on the car. This was in the last 2 years. Hope that helps.
     
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