Reckless

iTrader: (9)

I will be going back to a stock short block for a while with the regular flat tops. Just wondering what kind of cam I can get away with since my heads are milled .050.

So if your heads are milled .050, what are your cam spec's and did you fly cut the pistons?

Thanks <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

AlonzoVersion 1.0

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Reckless:
<strong>I will be going back to a stock short block for a while with the regular flat tops. Just wondering what kind of cam I can get away with since my heads are milled .050.

So if your heads are milled .050, what are your cam spec's and did you fly cut the pistons?

Thanks <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Raughhammers heads are milled .060 and he is using a 224/224 dur .581/.581 lift 112 lsa with 4 degrees ground in.Terry Burger's are milled .015 and he is using 5.3 heads which brings his compression up to 11:3:1 I beleive and his cam specs are 229/229 dur and lift is in the .57*/.57* area with a 112 lsa I beleive.You should email those guys personally they will thell you their setup.Your compression should be right at 10:7:1 with your heads being milled .050.Every .010 you take off is worth 1 full point of compression which equates to 10:7:1 unless you have ls6 or 5.3 heads.I hope I helped you.Oh this is with no fly cutting by the way.

<small>[ July 17, 2002, 03:12 PM: Message edited by: Alonzo ]</small>

RyanJ

stock is 10.1:1.

if ~.006=1cc and .030=5cc and about 10.6:1; then .050 is more like 11:1. which makes more sense to me as i dont think raughammer is under 11:1.

Ryan

AlonzoVersion 1.0

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ryan:
<strong>stock is 10.1:1.

if ~.006=1cc and .030=5cc and about 10.6:1; then .050 is more like 11:1. which makes more sense to me as i dont think raughammer is under 11:1.

Ryan</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Raughhammer has stated he is running 10:8:1 compression.But we will let him speak on it.Hey I could be wrong though.

Patrick G

iTrader: (14)

Mine are cut .060. I run a 230/224 reverse split cam with big 2.055/ 1.60 valves. We fly cut the stock pistons because the p to v was too tight. It would have been OK with 2.02 valves, but not with 2.055s...just a hair too close for comfort.

RyanJ

i could be wrong on my .006 figure. i mean when you cut that first .006 off, youre losing less chamber volume right? i see a lot of guys list 10.4:1 with .030 off, but close to 11:1 or higher with .060 off.

Patrick G

iTrader: (14)

My heads were cut .060 and when cc'd, they measured 61cc's. This calculated out to 10.90 compression (using my conversion numbers). Since stock LS1s are around 67cc's, I would think that each .010" cut from the head would subtract 1cc. At least they did on my heads, FWIW.

AlonzoVersion 1.0

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ryan:
<strong>i could be wrong on my .006 figure. i mean when you cut that first .006 off, youre losing less chamber volume right? i see a lot of guys list 10.4:1 with .030 off, but close to 11:1 or higher with .060 off.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Its wierd how it works huh?I am still not sure myself but I use to beleive that I had 10:8:1 compression with my heads being milled .030 but someone told me it was wrong. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

VINCE

iTrader: (1)

Mine according to the head porter are .060.. The first time he told me they were .040. Who knows. I am running the XE-R 226/.585 lsa 112 cam.

Reckless

iTrader: (9)

Good replies guys! I think I will contact Raughy (john) and see what he says.
Todd

MDL-01C5

So you guys with the heavy decking...what are your actual P/V clearances with those big cams--and what brand of valves are you using?

steve

mine are right at 57 cc right now but they aint been cut..

<img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

steve frank

DriveATransAm

mine are 0.050 cut. i have a comp cam (224 563 lift). i tested out the stock length pushrods today, and clearance looked ok, but im gonna double check it tomorrow cause the clay sorta ended up on the floor before i could really check well, lol. if you are really worried about p/v clearance, you can always put shorter rods in (which im trying to decide right now).

i was under the impression that .050 was about 11.3 cause i heard that 0.040 is one full point, making it 11.1.

Tin Indian

Dont know about .050"

But ... more than 1 engine builder has been here and LS1.Com and stated that milling .030" on 5.7 heads will yeild a 10.5 CR

L4m3r

so should i be fine with 2.055 or 2.02 valves with a 226/230 on 6.0ltr heads taken down .050 <img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" /> i have a GTP 220 cam and its just not doing it for me... Also should i be running a 7.35 or 7.4 pushrod?

DriveATransAm

heres an interesting thread i found on it before: https://ls1tech.com/ubb/cgi-bin/ulti...=004018#000000

Speed Demon

iTrader: (14)

Don't forget the type of valves will affect the final chamber volume some.

I milled my 6.0L heads 0.30 and the final chamber volume was 63.5 cc. I think this equates to around 10.5 ~ 10.6:1 C/R.

I am using Ferrea vavles which are flat faced, unlike the stock valves which have a dimple on the combustion side.

CHRISPY

Raughammer has a non stock bottom end now right?
Are his pistons in the hole at all or valve reliefed?
Cheers,
Chris

chuckhammer

Remember that the combustion chamber is somewhat tapered as you move upward towards the top (valves, plug, etc.). Due to this shape, the relationship between how much is milled of the head and the resulting combustion chamber volume is not linear. For any given amount you mill off the bottom of the head, you will be increasing the CR less and less as you continue milling in that same increment.

Ex: If the first .030 bumps your CR up by 0.5, then the next .030 may only give you another .3 or .4.

AlonzoVersion 1.0

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>Raughammer has a non stock bottom end now right?
Are his pistons in the hole at all or valve reliefed?
Cheers,
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">He has stock pistons with no valve reliefs the last time I heard.