Results 1 to 7 of 7
  1. #1
    Member egod's Avatar
    Join Date
    Feb 2008
    Location
    Chicago
    Posts
    436

    Navy Blue Metallic
    1999 Trans Am

    compression on new build

    So i'm still in the beginning stages of my engine build for 2011, meaning still researching I suppose. I want to buy things in stages due to cash but want to have it all bought before i start assembly. I pretty much know what parts i think i am going with, as well as the intentions of the motor. However, I would still like some input as to a good compression ratio. Let me start with a few basics:

    1. LQ4/9 408 stroker
    2. N/A with n2o
    3. looking to make 500 N/A RWHP
    4. Street driven/ maybe daily

    I know there is a big difference in static compression and dynamic and I know the later is more important. So keeping in mind it will be street/DD the cam wont be very aggressive thus, dynamic should not differ to much from static. So what would anyone suggest for a good CR for a 500HP N/A motor with spray?

  2. #2
    Member egod's Avatar
    Join Date
    Feb 2008
    Location
    Chicago
    Posts
    436

    Navy Blue Metallic
    1999 Trans Am

    So...I was thinking 10.5:1 for pump gas is okay...anyone disagree?

  3. #3
    Awaiting Activation
    Join Date
    Oct 2007
    Location
    NC
    Posts
    635

    SOM
    1998 T.A.

    11.2 11.3ish is fine for pump gas with these cars. I have seen guys run higher. Good quench is the key to running higher compression w/o predetonation. Optimum quench is .035-.040 for a pump gas LSx. Here is a calculator to help you figure out your setup>>>>>> http://www.rbracing-rsr.com/squishcalc1.html

  4. #4
    cutting and welding mark21742's Avatar
    Join Date
    Mar 2008
    Location
    mercersburg pa
    Posts
    6,443

    hugger orange
    2004

    I'm running my 408 at 11:1 on 93 with no problems at all. 238/242 .595/.595 112lsa I do daily drive mine.

  5. #5
    Member egod's Avatar
    Join Date
    Feb 2008
    Location
    Chicago
    Posts
    436

    Navy Blue Metallic
    1999 Trans Am

    does having a cam with a wider lsa make it tamer even with high lift and duration? it sounds like a can get a lot more out of the setup i was planning and still have a lot more streetability than anticipated

  6. #6
    Impounded
    Join Date
    Apr 2006
    Location
    park bench
    Posts
    1,399
    gmcheviac

    wider lsa will be tamer and have a broader powerband

  7. #7
    cutting and welding mark21742's Avatar
    Join Date
    Mar 2008
    Location
    mercersburg pa
    Posts
    6,443

    hugger orange
    2004

    Quote Originally Posted by egod View Post
    does having a cam with a wider lsa make it tamer even with high lift and duration? it sounds like a can get a lot more out of the setup i was planning and still have a lot more streetability than anticipated
    Yes it will be "tamer", but you will a get higher peak torque with a tighter lsa... A lot of time you spread your lsa farther than optimum to get a better, lower and more streetable idle

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Question: 10:1 compression FI build - Opinions wanted
    By Hi-Po in forum Forced Induction
    Replies: 6
    Last Post: 03-25-2010, 12:38 PM
  2. 500CI Chevy LS1 Engine Build - How To Build A 500C
    By Ed Blown Vert in forum Camaro / SS
    Replies: 0
    Last Post: 02-17-2009, 07:10 PM
  3. compression
    By 00ssls1 in forum Internal Engine
    Replies: 0
    Last Post: 05-28-2008, 07:18 AM
  4. compression
    By Bender10 in forum Internal Engine
    Replies: 4
    Last Post: 03-17-2008, 03:53 AM
  5. compression
    By fastbuff in forum General Help
    Replies: 6
    Last Post: 12-16-2006, 12:18 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
  •