Ok, 0.0 decked. Domed pistons. What's my compression?

[Eliminator SS]

Ok, after that last post about my block being 0 decked I need to refigure what my actual comp ratio is.
Block is 0 decked. .041" head gaskets. 72CC heads. .100" dome on top of pistons with valve reliefs. 4.030" bore.
None of the calculators will let me have a 0 decked block and 0cc's of space downbore.
I've always guessed somewhere close to 10.5:1.

[tbeg274]

You didnt give your stroke or gasket bore but if your using a 3.48 crank, my calculator puts you around 10.1

[Eliminator SS]

Yep, 3.48 crank and unsure of bore.

So which is it?

Originally Posted by Eliminator SS

Yep, 3.48 crank and unsure of bore.

Originally Posted by Eliminator SS

Block is 0 decked. .041" head gaskets. 72CC heads. .100" dome on top of pistons with valve reliefs. 4.030" bore.

What brand/model of pistons are in it? This will give you a more exact static compression ratio calculation.

[Eliminator SS]

Keith Black
http://store.summitracing.com/defaul...=egnsearch.asp

[Eliminator SS]

Unsure of the gasket bore!

Originally Posted by Eliminator SS

Unsure of the gasket bore!

Oops, missed that part. LOL!

Most 350 gaskets are 4.166" bores. But they are not round. What brand/model head gaskets do you run?

[Eliminator SS]

Felpro premium blue gaskets.

[tbeg274]

I would say your right around 10.1:1 Are your heads iron or aluminium?

[Eliminator SS]

Iron 72CC Goodwrench bowtie heads.

Hmm. Maybe that's why no one can duplicate my build around here. Because I never knew that it was zero decked.

Full specs are:
Eagle Forged crank.
Eagle H-beam rods.
Crane H-302 cam. (Used to be called 3/4 Race Cam)
Keith Black dome top pistons (10-10.5:1)
Block bored .030, zero decked, align honed, balanced and blue printed.
GM Goodwrench aftermarket heads, ported (75%) and polished.
Proform roller rockers.
Weiand high rise, single plane (high RPM) intake.
Holley 780 single pumper.

Engine setup dyno'd at over 400hp and over 400ft/lbs of torque!
Now I know why! lol
Thank you, thank you. I know I'm good.
Really most of it was my machinest. He builds race only motors, so that's mostly why his work is so good.

Go look up the part number at http://store.summitracing.com for your head gasket. They list all the felpros with a compressed thickness and volume.

For instance, the Felpro Permatorque MLS for the 350 has 8.7cc with a .039" compressed height.

http://store.summitracing.com/partde...autoview=s ku

The Felpro 1003 with a .041" compressed height has a 9.1cc volume.

Also, it appears that most 350 head gaskets from Felpro have a 4.125" bore.

[Eliminator SS]

It was a trick flow set with Fel Pro Blue stripe gaskets.
I can't find the number for the head gaskets on the box.
But I'm pretty sure I remember them saying .041 on the gaskets themselves.

[tbeg274]

You may want to confirm this with an expert, but thats a lot of compression for iron heads. That is unless you plan to use racing gas. If so, thats a killer engine.

[Mwilson]

8 Cyl Engine Bore (in.)4.030 Your Engine Displacement is:355.12 Engine Stroke (in.)3.480 Piston Deck Height (in.)0.000 Your Piston-to-Head clearance is (in.):0.041 head gasket Head Gasket Vol (cc)10.0 Your Head Gasket Volume. is (ci.):0.610Combustion Chamber Vol. (cc)72 Your Deck Clearance Volume is (ci.):0.000 Piston valve reliefs (cc) 0 Your Comb. Chamber Volume is (ci.):4.394 - Your Piston relief/dome Volume is (ci.):0.000 Total single cylinder volume is (ci):49.394 Total single cyl. compression vol is (ci):5.004 Your Compression Ratio is: 9.87:1


my .125 domes worked out to +1.5cc after cc'ing so im guessing yours even out to 0.
I run 93 octane with 62.5cc Iron heads.

[lapedr]

Does anyone know a link to where I can download a compression ratio calculator or use one online?