COMPRESSION

Old 09-21-2011, 05:42 AM
  #1  
JEFF69Z28
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Apr 2008
Posts: 496
Default COMPRESSION

How much power is it worth and what is the easiest way to get it and how do i know how much i need.right now im @ 11.50 with flat top 2 valve relief pistons,65 cc on afr 210 heads,pistons are 15 thousands in the hole @ tdc.406 sbc.cam is 260/[email protected]/645, 108lsa, sold roller motor
JEFF69Z28 is offline  
Old 09-21-2011, 10:15 AM
  #2  
curtisreed
Senior Member
RACING JUNKIE
 
curtisreed's Avatar
 
Join Date: Feb 2004
Location: KIEFER, OK.
Posts: 1,312
Default

I think it would be worth your time to gain some compression. There is no fast and easy formula to tell you how much you would pick up per point. The easiest way would be to have your heads cut. You will have to watch P to V clearance. Closing up the quench area would do you a big favor but being .015 down the hole there is not much you can do about it.

Why so far below the deck? You are running gas right?

Curtis
curtisreed is offline  
Old 09-21-2011, 02:19 PM
  #3  
markdunlap
Senior Member
DYNO OPERATOR
 
Join Date: Jan 2004
Location: central Illinois
Posts: 459
Default Compression

If you want compression, pistons are what you need. If that is not practical, stay with what you have or sell it and build a high compression engine.

13.5 compression is common, but it takes better parts to make it durable and powerful.
markdunlap is offline  
Old 09-21-2011, 03:48 PM
  #4  
wmeabates
Senior Member
MASTER BUILDER
 
Join Date: Sep 2005
Posts: 134
Default

With a .040 head gasket and the other info You listed You're compression now is 11.15 to 1.If You went to 0 deck clearance You would be 11.5.Bill.
wmeabates is offline  
Old 09-22-2011, 01:40 AM
  #5  
JEFF69Z28
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Apr 2008
Posts: 496
Default

Originally Posted by doorracer
I think it would be worth your time to gain some compression. There is no fast and easy formula to tell you how much you would pick up per point. The easiest way would be to have your heads cut. You will have to watch P to V clearance. Closing up the quench area would do you a big favor but being .015 down the hole there is not much you can do about it.

Why so far below the deck? You are running gas right?

Curtis
Thats what the builder told me but i could of misheard him nothing has been done to the block,he used a real thin cometic gasket to get the 11.50(.25?),the block is a stock chevy 400.
JEFF69Z28 is offline  
Old 09-22-2011, 04:08 AM
  #6  
wmeabates
Senior Member
MASTER BUILDER
 
Join Date: Sep 2005
Posts: 134
Default

A .025 gasket with Your other info would be 11.5 to 1.I have a 412 sbc, 2 years ago I replaced a GM block with a Dart little M and new pistons,went from 13 to 1 to 14.5 to 1.Best et before 9.79, after 9.67.Bill.
wmeabates is offline  
Old 09-22-2011, 07:51 AM
  #7  
curtisreed
Senior Member
RACING JUNKIE
 
curtisreed's Avatar
 
Join Date: Feb 2004
Location: KIEFER, OK.
Posts: 1,312
Default

I agree with Mark that pistons are a good way to go, what I stated was the easiest. That's what you asked for. To me though having a flatter piston and getting the compression I want is better. Nothing getting in the way of the flame front and angle milling rolls the valve angle.

I don't know what is in your engine regarding " selling what you have and building a high compression motor". The parts in the bottom you have now may be fine.

This is not an attack on Mark's comments. He could be right, I just don't know specifically what you have in your engine. Just my opinion on what you are wanting to do.

Again, is this on gas?

Curtis
curtisreed is offline  
Old 09-23-2011, 01:50 AM
  #8  
JEFF69Z28
Senior Member
DYNO OPERATOR
Thread Starter
 
Join Date: Apr 2008
Posts: 496
Default

Originally Posted by doorracer
I agree with Mark that pistons are a good way to go, what I stated was the easiest. That's what you asked for. To me though having a flatter piston and getting the compression I want is better. Nothing getting in the way of the flame front and angle milling rolls the valve angle.

I don't know what is in your engine regarding " selling what you have and building a high compression motor". The parts in the bottom you have now may be fine.

This is not an attack on Mark's comments. He could be right, I just don't know specifically what you have in your engine. Just my opinion on what you are wanting to do.

Again, is this on gas?
YES 110 VP,JE FLAT TOPS 2 RELIEF,EAGLE CRANK/6 INCH RODS/BULLET CAM/GS ROLLER LIFTERS/SUPER VIC INTAKE 1050 HP HOLLEY.CAM SPECS ARE ABOVE POST

Curtis
JEFF69Z28 is offline  
Old 09-23-2011, 06:13 AM
  #9  
cncmotorsports
Senior Member
MASTER BUILDER
 
Join Date: Apr 2003
Location: Brookings South Dakota
Posts: 244
Default

With that cam profile, and Carb, I would throw some compression at it.
14.0+ depending on what Gas you can get.
Be carefully with that stock block.
cncmotorsports is offline  
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service