Generation Specific => Second Generation 1970-1981 => Topic started by: pete315 on May 09, 2025, 01:58:30 PM

Title: 77 Trans Am 6X-8 to a 6X-4
Post by: pete315 on May 09, 2025, 01:58:30 PM
I just bought a 77 Trans Am from original owner with 72,000 miles. I'm assuming it has the 6X-8 heads. My friend has a set of rebuilt 6X-4 heads he never installed on his car. Would I see a noticeable increase in power with these heads on? Timing chain has never been replaced so I want to change that right away. Is it worth swapping heads and leave the stock 6X-8 cam in car? Or should both the heads and cam be changed to notice any improvement in power? I'm guessing the 6X-8 cam is different than the 6X-4 cam. Thanks for any info.
Title: Re: 77 Trans Am 6X-8 to a 6X-4
Post by: b_hill_86 on May 09, 2025, 06:24:38 PM
I don’t pretend to be an engine guru but the 4s are smaller chambers which will bump compression up a little which won’t hurt. Would a new cam work better with the slightly higher compression? Probably but I can’t say for sure. Check out performance years forum. Lots of engine gurus on there that can accurately answer your questions.