|
Re: What compression would you run with a 499 stroker?
[Re: challengermike]
#1123591
11/28/11 08:08 PM
11/28/11 08:08 PM
|
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
the good in your favor: alum heads and good quench (zero deck/.039" gaskets right?). First I'd find the stealths' cc's & valve relief CC's & plug it all into KB's calculator & post your SCR. WAG 10 ish. I'd much rather be a slight bit low on DCR & run an aggressive adv curve. EDIT that's 10 ish maybe that I would shoot for
Last edited by RapidRobert; 11/28/11 08:43 PM.
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: dogdays]
#1123594
11/28/11 09:34 PM
11/28/11 09:34 PM
|
Joined: Jan 2003
Posts: 12,194
Benton, IL.
DaveRS23
Special needs idiot
|
Special needs idiot
Joined: Jan 2003
Posts: 12,194
Benton, IL.
|
Just how high you can go depends on a lot of factors like; how loose is the converter, how fast does the timing come in, what gears are in the car, how heavy is the car, how long does it hold in each gear, how do you drive it, etc, etc.
My Cuda is 3,450lbs with 3.91s and a fairly loose converter. The engine is 499" with a cam similar to yours. I run 11:1 on pump swill. As long as I keep it 180* or so, it does fine.
Master, again and still
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: challengermike]
#1123595
11/28/11 09:57 PM
11/28/11 09:57 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Im not sure what to put into this spot
Intake Closing Point (degrees)ABDC @ 0.050 lift plus 15 degrees
My cam cam only shows this spec for valve timing @ .015, its 71 abdc
The compression (static) is just the volume... what
really counts is the dynamic compression, thats when
the intake closes(you dont make compression with
the intake open) then its where is the piston in the
cyl when the intake closes... but with the dynamic
compression I would look at about 9.1 or so... static
MIGHT be about 10.8 or so
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: BradH]
#1123597
11/28/11 11:00 PM
11/28/11 11:00 PM
|
Joined: Oct 2005
Posts: 4,956
WI
Dcuda69
master
|
master
Joined: Oct 2005
Posts: 4,956
WI
|
Quote:
It's a street car, right? Build it at 10.0 and don't worry about the next time the local pump gas octane drops another point (or 2) when the Feds screw around w/ fuel again. You'll have enough torque w/ the extra cubes that you'll never miss the additional CR.
 Exactly what I did with my 470". It's at 10.2:1 and runs fine on anything I put in it!  
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: challengermike]
#1123599
11/28/11 11:39 PM
11/28/11 11:39 PM
|
Joined: Feb 2005
Posts: 4,318
Prospect, PA
BSB67
master
|
master
Joined: Feb 2005
Posts: 4,318
Prospect, PA
|
Quote:
Im not sure what to put into this spot
Intake Closing Point (degrees)ABDC @ 0.050 lift plus 15 degrees
My cam cam only shows this spec for valve timing @ .015, its 71 abdc
There are several different DCR calculators that use different closing points (if that makes any sense). Your .015" and 71 ABDC intake closing is based on seat or advertised duration, asuming that your lash is set at .022", you have 1.5 rocker ratio, and the cam is installed at 106 ICL. Your .050" duration intake closing point is 52 ABDC, again, assuming a 106 ICL.
At 10.4, and 1000 ft above sea level, you'll be on the edge of dentonation, IMO.
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: BSB67]
#1123601
11/28/11 11:51 PM
11/28/11 11:51 PM
|
Joined: Aug 2003
Posts: 1,062
Amherst,NY
challengermike
OP
super stock
|
OP
super stock
Joined: Aug 2003
Posts: 1,062
Amherst,NY
|
Quote:
Quote:
Im not sure what to put into this spot
Intake Closing Point (degrees)ABDC @ 0.050 lift plus 15 degrees
My cam cam only shows this spec for valve timing @ .015, its 71 abdc
There are several different DCR calculators that use different closing points (if that makes any sense). Your .015" and 71 ABDC intake closing is based on seat or advertised duration, asuming that your lash is set at .022", you have 1.5 rocker ratio, and the cam is installed at 106 ICL. Your .050" duration intake closing point is 52 ABDC, again, assuming a 106 ICL.
At 10.4, and 1000 ft above sea level, you'll be on the edge of dentonation, IMO.
using the 52 @.050
that gives me
DYNAMIC EFFECTIVE COMPRESSION RATIO
8.511
STATIC COMPRESSION RATIO
9.773
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: challengermike]
#1123602
11/28/11 11:57 PM
11/28/11 11:57 PM
|
Joined: Jan 2007
Posts: 7,664
IN
ahy
master
|
master
Joined: Jan 2007
Posts: 7,664
IN
|
I run 10.2 in an Ed headed 496 with 243@.050 cam. I figured I could push it a bit more to 10.4-10.6 but I like having a little margin in case of sustained hard running or so-so gas.
|
|
|
Re: What compression would you run with a 499 stroker?
[Re: challengermike]
#1123603
11/29/11 12:03 AM
11/29/11 12:03 AM
|
Joined: Dec 2010
Posts: 392
Mississippi
lahatte
enthusiast
|
enthusiast
Joined: Dec 2010
Posts: 392
Mississippi
|
You shouldn't use the .050 number for calculating Dynamic Compression Ratio. Air can still be pushed out of the combustion chamber through the .050" open valve, and thus, not compressed. The true DCR theoretically begins when the intake valve closes. Some cam specs will give an angle After BDC (.006 gap). I think that's a better number to use for calculating DCR because the valve is pretty nearly closed then.
Last edited by lahatte; 11/29/11 12:22 AM.
|
|
|
|
|
.jpg){kind=link}
.jpg){kind=link}