Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

PAC 1218's with a F13????

Thread Tools
 
Search this Thread
 
Old Feb 10, 2010 | 04:38 PM
  #1  
S13LSx's Avatar
Thread Starter
On The Tree
 
Joined: Nov 2009
Posts: 104
Likes: 1
Default PAC 1218's with a F13????

are they enough spring or would you go with something else?? 1518?
Reply
Old Feb 10, 2010 | 09:35 PM
  #2  
S13LSx's Avatar
Thread Starter
On The Tree
 
Joined: Nov 2009
Posts: 104
Likes: 1
Default

230/232 and .595/.585 on a 112 LSA

are the 1218's enough or would you go 1518's?

Will also be swapping in a set of 243's off a c6 vette. Would like to know how much I can shave off to raise the compression a little when I clean them up and install the valve springs at the machine shop. I was thinking .005-.010??? The 243's have 64.45cc chamders stock and I would like to take them down to a little over 60cc.

might need a 114 lsa to clear???
Reply
Old Feb 10, 2010 | 10:39 PM
  #3  
01ssreda4's Avatar
TECH Senior Member
15 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (96)
 
Joined: Aug 2007
Posts: 24,241
Likes: 89
From: Turnin' Wrenches Infractions: 005
Default

1218s will work fine, as well as 1518s would be even better, however I would check installed heigth.
Reply
Old Feb 10, 2010 | 11:47 PM
  #4  
LTX355's Avatar
Launching!
iTrader: (15)
 
Joined: May 2009
Posts: 242
Likes: 1
From: TX
Default

Originally Posted by 01ssreda4
1218s will work fine, as well as 1518s would be even better, however I would check installed heigth.
it has probably been done many times but i would chose option 2 to b on the safe side plus 1518s will live way longer because they will always b further away from coil bind...
Reply
Old Feb 11, 2010 | 06:31 AM
  #5  
S13LSx's Avatar
Thread Starter
On The Tree
 
Joined: Nov 2009
Posts: 104
Likes: 1
Default

Originally Posted by LTX355
it has probably been done many times but i would chose option 2 to b on the safe side plus 1518s will live way longer because they will always b further away from coil bind...
Thanks for the info. I'm going 1518's for durability then.

I found this on performancetrucks.net

So you want to figure out how much to mill:

It takes about .005" milling of the block deck to remove 1cc of volume. It takes .007" milling to remove 1cc from an LS1 head

Simple Milling Math:

You have a stock 66cc chamber and you want to get down to 63cc

66-63 = 3. You have to remove 3cc's

.007 x 3 = .021. So to get your 66cc chambers down to 63cc you'd have to mill ~.021.

You can also do the reverse, say you want to mill a head .030 to figure out how many CC's that removes you take .030 / .007 = ~ 4.28. Milling a stock 5.7 head .030 puts your chamber at ~ 62.
I guess I will try and take about .015-.018 off and try to get the heads right at 62cc chambers. That should put it very close to 11.0-1 with long tubes, ls6 intake, stock 243's, and a F13 cam with PAC 1518's. Should make a nice street driver with 3.73's and a 26" tire at the track. BTW it's a M6 car.
Reply
Old Feb 16, 2010 | 01:23 PM
  #6  
KennethS's Avatar
Teching In
 
Joined: Nov 2007
Posts: 29
Likes: 0
From: Detroit Metro
Default

1218 = 1518

1518's are just nitrided and polished..among other things

They're rated .650 because the nitriding allows for higher stresses (on a spring, highest stresses are on the surface).
Reply
Old Feb 16, 2010 | 02:02 PM
  #7  
SOMbitch's Avatar
TECH Senior Member
iTrader: (8)
 
Joined: Sep 2007
Posts: 6,881
Likes: 3
Default

Even though they may be rated to .650 I would run a double because the lobes are so aggressive.....
Reply




All times are GMT -5. The time now is 11:35 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE