quick CR estimate on KB107's

[ColeTrickle74]

Heyo, can anyone help me out with the estimated comp ratio on a standard bore and stroke 360 with 66cc eddy heads and KB107 pistons? (With the usual .039 or .040 gasket.) Just doing some research, rest of the project would include a SP manifold, 750 carb, 3000k converter, and a 292/ 292 with about 500~ lift. Too aggressive for a street/strip machine on 91 octane?

 

[lead69]

Heyo, can anyone help me out with the estimated comp ratio on a standard bore and stroke 360 with 66cc eddy heads and KB107 pistons? (With the usual .039 or .040 gasket.) Just doing some research, rest of the project would include a SP manifold, 750 carb, 3000k converter, and a 292/ 292 with about 500~ lift. Too aggressive for a street/strip machine on 91 octane?

This is a great calculator to play around with.http://kb-silvolite.com/calc.php?action=comp

 

[70aarcuda]

you will need to know how far down in the hole the pistons are in order to get the correct compression ratio..

i am building a .020 over 360 with the same pistons...without decking the block mine are down .016 in the hole...

i am going to use a .028 head gasket from Mr Gasket pn 1121 to get a .044 quench...

 

[ColeTrickle74]

I was messing with a few calculators, but the block isn't apart yet so I was just trying to find a rough estimate before I start purchasing things. Hoping it will run on 91.

 

[dgc333]

I had my 360 block machined to put the KB107's at zero deck. I am running magnum heads that cc'd at 64. With an 0.039 gasket that works out to 10.6:1 compression. I have a cam with less duration 268/280 which will give you more cylinder pressure than your 292/292 cam. I have 185-195 psi of cranking pressure. My engine runs on 89 octane and I can run 87 in a pinch if I take it easy.

If you don't deck your block block you can figure the compression will be under 10:1. With closed chamber aluminum heads and your cam you could easily run 11:1 on 91.

 

[388dart]

± 10.2:1 the Eddys are 63cc - least thats what they advertise - which will help. with aluminum heads and a tight quench (±.040) you should target for 10.5. it will still run on 91.

 

[rumblefish360]

a SP manifold, 750 carb, 3000k converter, and a 292/ 292 with about 500~ lift. Too aggressive for a street/strip machine on 91 octane?

This combo on my last engine which was a .030 360 was a nice street engine. Though I moved to the Air-Gap later.
The above posters, I agree with. Though I had ethier 89 or 93 to deal with. It's good to see them speak up on it.

 

[ColeTrickle74]

Awesome responses, thanks again. I wasn't 100% sold on the single plane manifold, the air gap was another one I was considering. This is coming up soon so I'm hoping to find some nice stuff.

http://worlddragexpo.com/