Recent content by RockLakeYachtClub

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    Summit vortec heads

    It's better than it was stock. In addition to the mods listed already, I also advanced the cam to 5 degrees BTDC. I also have a '98 ECSB Silverado, L31, totally stock, and the Suburban is more fun when I stomp on it to merge with highway traffic. At one time, I got 17mpg highway with it...
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    Low budget build without LS Swap

    Thanks - I didn't know about that! (Now I just need to find the BIN for that...)
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    Summit vortec heads

    That's just what I have - the MPFI upgrade, with an L31, Summit iron heads, and the LT4 hotcam. (You have a little less lift than I do with 1.5 rockers; you would have more with 1.6 and still be OK with the Summit heads.) L31 MaxExpress is right - I have never had any lean fuel issues with the...
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    Low budget build without LS Swap

    With regards to tuning: just did a search on gmt400 for free/open source tuning software called "PCM Hammer," and did not find anything. There may be free software on the 'net for the black box (search "Dimented24x7" or "PCM Hacking 101" on ThirdGen.org), but the LS computer (aka "411") has free...
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    Summit vortec heads

    I have the SUM-151124 heads on my '97 Suburban. (Made by Dart.) Installed them the way they came. The Comp 981 springs are listed as having a spring rate of 373. I also installed an LT4 Hotcam at the same time. Never any problem with this combo. (Bought/installed early 2014, 25K miles on them...
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