Aha, two messages that I felt were spam from 2022, I thought I'd opened them, but maybe not. Both were "I have a friend who has the parts your looking for".
Thanks Tom! It was in primer for a decade and I got most of the bodywork done in college but never got a chance to paint it. Last September, I finally got it disassembled after getting it running, driving, and tuned, and committed myself to finally painting it. Had some tiger stripes in it from poor paint technique so I wet sanded it and painted it again it came out more orange-peel-ey but the color was consistent this time. I was happy enough with it being the first time painting a car and wanted to get it running and driving for the spring. Now it's time to tear the interior apart and finish sewing up the seat covers and making the headliner and interior panels.
Will do Beater! I wanted to get this car to the GS nationals in more-or-less this current state in the early spring with it running and driving to show it off a bit before anything possibly goes terribly wrong. Then I plan to turn up the boost a bit more and turn up the max RPM a bit more past 5000.
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I was a bit curious on y'alls thoughts on the timing map which you can kinda see in this video When running 93 octane, my total timings at WOT are - no boost is 24-26* - 7psi is 18* - 14psi is 9* Tom, in your turbo 250 video when you had it in the dyno cell, is this timing anywhere close to the ballpark you were in? Did you have a something close to 9.3:1 compression or was it like 8:1 or 8.5:1?
I have a knock sensor linked to my computer so I can visualize any knocking which is what you see on the right half of the screen in that video. I'm super paranoid about detonation given my previous experiences and never paid super close attention to what total timing was on the stock motor or what I was running as total timing beforehand.
I tuned the timing table a ton and have taken the plugs out a million times to check for peppering (detonation) and put a boroscope into the cylinders to check the pistons. I have only ever seen very light detonation evidence on the pistons and very light peppering on spark plugs during tuning but the tune seems quite stable for the moment. Increasing the timing past this point didn't seem to result in much power gain but I figure these are already super conservative timings anyway. The timing amounts just seem super low given I thought total timing was like 32* stock and you're supposed to take like 1*/1psi to be on the safe side which would put me at wanting 18* @ 14psi instead of the 9* I am running. Idk maybe I'm just rambling. It runs well, and maybe 9.3:1 being on the higher end of compression ratios means I need to pull more timing than 1*/1psi. Curious for y'alls thoughts.
Yes, I had forgotten that those are machined as a pair. I'm sure many were mismatched.
When I was a kid my dad was a mechanic. He was also a machinist and was allowed to use the machine shop at a couple of the bigger parts houses in Amarillo. I often went with him. Those guys knew their stuff. When I was a counterman for several years I got to work with one of those old time lifelong parts guys. He taught me so much but there was more in his head than there was in the books.
Hi all, very similar post to one I just made in the engines forum about a GMC straight 6. Going to be some overlap of wording here because I'm not sure what the overlap between the two forums is and could use the assistance on both.
I have a working GMC Hydramatic, I believe this came out of a deuce and a half army truck and it was paired behind a 302. We just pulled this from my family's motor home as part of the process of getting it modernized and back on the road.
I'm struggling to figure out what a fair price to sell it would be. I've done a little looking and can't find any listings for these for sale, or even vehicles with them in them for sale or sold. GM didn't do me any favors by keeping the "Hydramatic" name running strong all these years later with their more modern stuff so the search results get really muddy.
Any insight into the value of something like this would be greatly appreciated.
To be clear, just so this doesn't get flagged as being in the wrong forum, once we have some more info about the market for these, I'll post a for sale in the swap meet here with pictures and more specifics. Just trying to continue educating myself before we sell it.
PS. I understand this is possibly an odd post, so by all means, feel free to PM me, or reply with any relevant info that might help.
