Results 1 to 8 of 8

Thread: 4AGZE Compression Advise needed

  1. #1
    Junior Member Grease Monkey _FNQ_rolla_'s Avatar
    Join Date
    Dec 2007
    Location
    Qld
    Posts
    51

    Default 4AGZE Compression Advise needed

    I have been looking through the forums and I have not found a thread relating to a 4AGZE with higher compression ratio then the 8.9 ratio.

    What I was thinking of doing is putting the sc12 (the small pulley of the AFM) on a 4AGE (NA motor) and still run the 10.3 pistons (from a SX 91 model seca).

    In having said the above, I plain on connecting the
    • 4AGZE wiring harness
    • 4AGZE factory ECU
    • 4AGZE AFM
    • 4AGZE injectors
    • 4AGZE intercooler

    Basically everything 4AGZE (AFM type) (which I bought a ½ cut car) with 10.3 pistons.

    I have the 8 : 1 pistons but I was just thinking about the 10.3 pistons as I am thinking that this might give a better engine response over the lower compression.

    This will be a daily drive car and will be kept in its standard form (NO changing of pulleys for higher boost, just the Toyota factory standard sc12 boost)

    I am new to supercharging/boost and just want to hear your experiences have you had, or could foresee with running the 10.3 pistons.

    Thanks
    Gav

  2. #2
    SC14 7AGZE Grease Monkey
    Join Date
    Jun 2007
    Location
    FL
    Posts
    144

    Default Re: 4AGZE Compression Advise needed

    The 10.3 pistons are a bad idea. I have not supercharged on them, but I did boost from a turbo on them, and 10psi later I had blown 3 out of 4 pistons within 2 months.

    The ringlands on those cast pistons are just too weak. Do yourself a favor and stick with the stock 8:1 or 8.9:1 forged pistons. Once you have a supercharger, you shouldn't need to be worrying about throttle response.

    Especially since your going to use the stock GZE ecu, and can't tune your ignition advance... you should stay away from high compression.
    SC14 7AGZE build: http://beasted86.webs.com/

  3. #3
    Junior Member Backyard Mechanic jono's Avatar
    Join Date
    Jun 2008
    Location
    NSW
    Posts
    243

    Default Re: 4AGZE Compression Advise needed

    there are plenty of turbo NA 4age out there running 10psi with no problems on an aftermarket ECU. always depends on the quality of the tune and fuel.
    previous:-> 74 KE20 4AGTE, 04 RZN149R, 01 AE112R, 01 KR42R, 84 E30 318i, 67 MINI DELUXE
    current:-> 06 BF XR6T, MY13 ISUZU D-MAX 4X4

  4. #4
    Cunning Linguist Domestic Engineer The Last Streetfighter's Avatar
    Join Date
    Oct 2005
    Location
    Qld
    Posts
    569

    Default Re: 4AGZE Compression Advise needed

    Add to your list Dizzy Delete for CAS/coilpacks.

    Stock Intercooler = bad idea. Go for a FMIC or aftermarket Top Mount over to the side (to cut down on heat soak off the engine).
    Stock ECU = bad idea. 1) You can't tune it for your fuel etc. 2) It will detect knock (you will get it) and pull timing and you will have a dog engine.
    There is nothing wrong with the high comp pistons, but you will want aftermarket management.
    You SAY you want stock boost and stock pulleys. But everyone knows that it NEVER stops there.
    AE90 Silvertop - GONE; 2001 ST215W GT-T Manual - SOLD; EP82 Starlet GT - Sold
    Now driving 20V Turbo 1.8 N-S FWD

  5. #5
    Junior Member Grease Monkey
    Join Date
    Dec 2005
    Location
    NSW
    Posts
    119

    Default Re: 4AGZE Compression Advise needed

    i'd stick with the gze, the piston are coated and can take a better beating.
    Also if you wanna up the compression try using a thinner head gasket

  6. #6
    Senior ****** Carport Converter Sam_Q's Avatar
    Join Date
    Nov 2005
    Location
    VIC
    Posts
    1,798

    Default Re: 4AGZE Compression Advise needed

    as libo said go for a thinner gasket or if you want to go even further get some metal taken off the head

  7. #7
    AVGAS DRINKING Carport Converter 30psi 4agte's Avatar
    Join Date
    Feb 2006
    Location
    S.A
    Posts
    1,457

    Default Re: 4AGZE Compression Advise needed

    I must say i agree with turbo4age.

    I would advise against it. Those cast pistons are weak as piss. Good tune or not.

  8. #8
    Junior Member Grease Monkey _FNQ_rolla_'s Avatar
    Join Date
    Dec 2007
    Location
    Qld
    Posts
    51

    Default Re: 4AGZE Compression Advise needed

    Thanks for the advice everyone, i will just stay with the factory 8:1 compression ratio as this will be safe for an everyday drive car.

Similar Threads

  1. My high compression + boost concept
    By Sam_Q in forum Tech and Conversions
    Replies: 88
    Last Post: 18-06-2012, 09:40 PM
  2. 4AGZE to 4AGTE in AE86 Info needed
    By BlueAE86 in forum Tech and Conversions
    Replies: 15
    Last Post: 17-06-2006, 11:15 AM
  3. AE101 4AGZE wiring diagram Needed
    By BlueAE86 in forum Tech and Conversions
    Replies: 18
    Last Post: 28-04-2006, 12:29 PM
  4. 20v compression (compression test)
    By 2revup in forum Tech and Conversions
    Replies: 4
    Last Post: 20-03-2006, 05:06 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •