 Compression Ratio, Will I be able to tell the difference? |
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| sdoolin |
 Feb 7 2025, 04:42 PM
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Member  Group: Members Posts: 417 Joined: 1-May 14 From: LouKY Member No.: 17,299 Region Association: None  |
Rebuilding(ish) my 2056. On my first build I was able to achieve a compression ratio of very nearly 9.0:1. With this build, I am having to add .020 spacers below the jugs to get any measurable deck height in the jugs. I am calculating a compression ratio of 8.6:1.
Will I notice the loss in compression ratio? |
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| sdoolin |
Mar 3 2025, 10:30 AM
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#2
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Member Group: Members Posts: 417 Joined: 1-May 14 From: LouKY Member No.: 17,299 Region Association: None |
Could this be a faulty oil pressure sending switch? Green ight goes out (indicating good pressure), then comes back on after a few moments?
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| VaccaRabite |
Mar 3 2025, 11:35 AM
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#3
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En Garde! Group: Admin Posts: 13,729 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region 
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QUOTE(sdoolin @ Mar 3 2025, 11:30 AM)  Could this be a faulty oil pressure sending switch? Green ight goes out (indicating good pressure), then comes back on after a few moments? Maybe. Or you are loosing pressure on warmup. There is usually a spike of oil pressure on start up that fades as the oil comes to temp. If you have an oil pressure gauge, what does it say? Are you using a stock idiot light switch? Stock one is supposed to light up at 3-4 psi. But you can find plenty of switches that light up a lot higher then that. The dual pole switches light at close to 10 psi. Which STILL should not be an issue on a fresh engine. Do the basic electric checks too. Make sure leads are tight and grounds are clean. If this was first start, the light may have come on while it pumped oil to other systems, especially if you have an external oil cooler. Zach |
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Posts in this topic
sdoolin Compression Ratio Feb 7 2025, 04:42 PM
technicalninja You need AT LEAST .036 with cast and .040+ with fo... Feb 7 2025, 05:38 PM sdoolin Measured deck height in the jug, with an .020 spac... Feb 7 2025, 06:02 PM Superhawk996 Sounds like you are playing with fire.
Without se... Feb 7 2025, 06:21 PM
sdoolin
Sounds like you are playing with fire.
Without s... Feb 7 2025, 07:26 PM Superhawk996
Sounds like you are playing with fire.
Without ... Feb 7 2025, 07:30 PM technicalninja
Measured deck height in the jug, with an .020 spa... Feb 7 2025, 06:57 PM sdoolin Yep, I don't want this help. Y'all go buil... Feb 7 2025, 07:27 PM worn
Yep, I don't want this help. Y'all go bui... Feb 14 2025, 07:12 PM sdoolin
Yep, I don't want this help. Y'all go bu... Feb 15 2025, 08:44 AM sdoolin I especially like the turd bit. Feb 7 2025, 07:29 PM sdoolin Superhawk thank you for your reasonable response. ... Feb 7 2025, 07:33 PM Superhawk996
Superhawk thank you for your reasonable response.... Feb 7 2025, 07:44 PM Jack Standz
Rebuilding(ish) my 2056. On my first build I was ... Feb 8 2025, 03:05 AM sdoolin
Rebuilding(ish) my 2056. On my first build I was... Feb 8 2025, 07:35 AM sdoolin Bolted things up on one side of the engine today a... Feb 8 2025, 12:37 PM Superhawk996 0.100” clearance to the exhaust valve is startin... Feb 8 2025, 01:43 PM Jack Standz
Bolted things up on one side of the engine today ... Feb 8 2025, 03:04 PM sdoolin Thank you both for the thoughtful replies. My orig... Feb 8 2025, 04:32 PM Superhawk996 0.140” - 0.150” clearance to exhaust valves is... Feb 8 2025, 10:28 PM sdoolin Measured valve lift a bunch of times today. Worst ... Feb 9 2025, 05:03 PM sdoolin I'll likely button this engine up this weekend... Feb 14 2025, 02:27 PM Jack Standz Modified #2.
Bolt transmission to engine. Remove... Feb 14 2025, 04:41 PM sdoolin
Modified #2.
Bolt transmission to engine. Remov... Feb 15 2025, 08:38 AM 930cabman Have you checked crankshaft end play? Feb 14 2025, 04:52 PM sdoolin
Have you checked crankshaft end play?
So I re-c... Feb 16 2025, 04:08 PM Al Meredith Years ago when Len Hoffman was rebuilding heads he... Feb 15 2025, 05:02 PM worn
Years ago when Len Hoffman was rebuilding heads h... Feb 15 2025, 08:49 PM Superhawk996 No discernible crank end play is a no-go.
Redo ... Feb 16 2025, 04:30 PM sdoolin
No discernible crank end play is a no-go.
Redo... Feb 17 2025, 08:09 AM stownsen914 Separate from the crank end play, if you are askin... Feb 17 2025, 08:15 AM sdoolin
Separate from the crank end play, if you are aski... Feb 17 2025, 01:16 PM sdoolin I have measured all of the shims I have on hand (6... Feb 18 2025, 05:25 PM sdoolin So, I re-measured crank end play. Installed flywhe... Feb 22 2025, 01:05 PM Superhawk996
Am I looking for .004" thrust with all thr... Feb 22 2025, 01:16 PM sdoolin Thank you Superhawk. Installed third shim, remeasu... Feb 22 2025, 02:04 PM Superhawk996
Thank you Superhawk. Installed third shim, remeas... Feb 22 2025, 07:09 PM Jack Standz Add a cable from the negative side of the battery ... Feb 22 2025, 02:24 PM Superhawk996 I’m going to ask a question that I’ve assumed ... Feb 22 2025, 07:17 PM sdoolin
I’m going to ask a question that I’ve assumed... Feb 23 2025, 09:20 AM Jack Standz It's a good idea to fill the oil filter with o... Feb 23 2025, 02:51 PM sdoolin I have confused myself. It happens.
Having re-in... Feb 27 2025, 10:37 AM Superhawk996 Follow the Haynes or factory manual to instill the... Feb 27 2025, 12:15 PM sdoolin
Follow the Haynes or factory manual to instill th... Feb 27 2025, 04:02 PM sdoolin Engine went in on Friday. Easy peasy. After I pour... Mar 2 2025, 05:23 PM Superhawk996 If it were me I would not be starting the engine j... Mar 3 2025, 12:53 PM sdoolin Installed my brand new oil pressure test gauge (Ha... Mar 3 2025, 04:20 PM VaccaRabite Your pressure is high because the oil is cold and ... Mar 4 2025, 06:20 AM rfinegan Woohoo
glad you get the pressure...sounds like the... Mar 4 2025, 09:03 AM sdoolin Yep, cold oil and running (expensive) Brad Penn 20... Mar 4 2025, 09:10 AM sdoolin She's alive, and running well(ish). Drove abou... Mar 11 2025, 10:55 AM 930cabman
She's alive, and running well(ish). Drove abo... Mar 11 2025, 12:17 PM friethmiller @sdoolin ,
Congrats! Glad the build was succ... Mar 11 2025, 11:54 AM sdoolin Moving on to some other fiddly projects. Oil press... Mar 11 2025, 02:56 PM |
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