headwork and compression
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Road Captain
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From: San Diego
headwork and compression
06 Softail Deluxe with bassani 2into1, Fuel Moto AC, S&S 97 big bore and 583 cams.
I want to get some mild headwork done. S&S says that 97" with my stock heads is at 9.7 to 1. I'm guessing that that's static compression? I've read here that 583 cams are good when set at 9.8 to 1 and no more than 10 to 1. Is that static or corrected?
If I get headwork done what would i get the compression set at? Or should in stay at stock and just change the head gasket to .030 cometic.
I want to get some mild headwork done. S&S says that 97" with my stock heads is at 9.7 to 1. I'm guessing that that's static compression? I've read here that 583 cams are good when set at 9.8 to 1 and no more than 10 to 1. Is that static or corrected?
If I get headwork done what would i get the compression set at? Or should in stay at stock and just change the head gasket to .030 cometic.
Last edited by baloot-boy; Oct 13, 2014 at 12:41 AM.
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From: deland,florida
we use a lot of the .583`s.we set them at 9.8-1.make sure your heads are ported to the .583 cams,you don't want to get hogged out heads that will kill the low end grunt the .583`s are known for
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Road Captain
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From: San Diego
I guess I'll have to check what actual compression is with the S&S 97 kit and my stock heads with the 583. Im guessing its not gonna be close to 9.7 to 1 like it states on the website.
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Road Captain
Joined: May 2014
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From: San Diego
I already have the S&S 97" kit where its says id be at 9.7 to 1 compression with stock heads. Should I expect that's what im getting? I could change the head gasket to .030 to get the .2 bump. Would that be enough for my setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
Last edited by baloot-boy; Oct 14, 2014 at 10:49 AM.
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Joined: Nov 2014
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From: Michigan
I already have the S&S 97" kit where its says id be at 9.7 to 1 compression with stock heads. Should I expect that's what im getting? I could change the head gasket to .030 to get the .2 bump. Would that be enough for my setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
This will bring out the best performance for your engine. No more Pings (depending on CAM TYPE) and eliminates detonation.
Do the math now and you will be pleased. other wise you will be like most other people, completely dissatisfied with your Mods to your engine.
I might be new to this forum but, I cut my teeth on radial engines in aviation on now moved on to bigger and badder things.
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The closer you can put the piston to the head w/o contact under operating conditions/heat, the more turbulent the chamber, and the less chance of detonation, as long as the compression it set correctly.
We tighten the plug gap(.035") when pushing these up to/near 200 psi ccp, as extensive dyno knowledge has taught us.
Increasing the compression ratio generally requires a reduction in combustion chamber volume, via a domed piston, or machining the cylinder head.
Scott
We tighten the plug gap(.035") when pushing these up to/near 200 psi ccp, as extensive dyno knowledge has taught us.
Increasing the compression ratio generally requires a reduction in combustion chamber volume, via a domed piston, or machining the cylinder head.
Scott
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From: deland,florida
I already have the S&S 97" kit where its says id be at 9.7 to 1 compression with stock heads. Should I expect that's what im getting? I could change the head gasket to .030 to get the .2 bump. Would that be enough for my setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
Or let me re-phrase. What are my options for setting compression to 9.8 to 1 with my current setup?
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From: san antonio
Listen to Scott and Kirby; they have only been doing this for a gazillion years.
Never hurts to measure deck height as suggested by Anthony Paul but 88" cylinders are typically, in my limited experience, down in the hole .003"-.005"; not enough to justify trimming cylinders to achieve 0.00" deck height for a "street" build. While it is said that .030" is "ideal" squish, nothing wrong with .040" either. Cometic also offers a .027" MLS head gasket that might come in handy in your endeavor.
Never hurts to measure deck height as suggested by Anthony Paul but 88" cylinders are typically, in my limited experience, down in the hole .003"-.005"; not enough to justify trimming cylinders to achieve 0.00" deck height for a "street" build. While it is said that .030" is "ideal" squish, nothing wrong with .040" either. Cometic also offers a .027" MLS head gasket that might come in handy in your endeavor.