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.

 

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

 

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.

 

you be better off just having your cylinders bored to 98"

 

Yes,
More cost-effective to bore the OE cylinder.
Scott

 

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?

 

To get the best results you really need to set your "SQUISH". Get your TDC as close to .+002 - .+005 (means in the hole and not all the way to the top). This may require your cylinders to be cut down some. Put your .030 head gasket on. I try to get it (Squish) set around .034.

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.

 

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

 

cc your heads,never just accept what the manufacture states for compression,getting from around 9.7-1 to 98.-1 isn't a big deal at all,mill around .007 -.010 off the heads

 

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.