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

243 valve?

Thread Tools
 
Search this Thread
 
Old Feb 8, 2013 | 11:58 PM
  #1  
6togo's Avatar
Thread Starter
TECH Resident
iTrader: (13)
 
Joined: Feb 2012
Posts: 821
Likes: 0
From: Harford co. MD
Default 243 valve?

I just picked up a fresh pair of ported 243's with stock valves are the stock type and size valves decent? and was considering going with larger valves like 2.02/1.57 would that gain better flow #'s or not worth the trouble?
Here are the flow #'s for the heads i have and they were flowed with no pipe i guess thats why the exhaust seemed a bit low.

LIFT INT EXH
200 155.5 113.7
300 226.5 161.1
400 266.9 197.5
450 285.6 203.8
500 300.1 210.1
550 309.8 213.3
600 314.9 216.4

65cc chambers.
Reply
Old Feb 9, 2013 | 02:32 AM
  #2  
PREDATOR-Z's Avatar
TECH Senior Member
 
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Default

Not worth the expense IMO. 5>10cfm with no other swap but 2.00 for 2.02 valves.
Also usually aftermarket valves have thicker base and you then loose PTVc even further.
Reply
Old Feb 9, 2013 | 07:10 AM
  #3  
96capricemgr's Avatar
11 Second Club
iTrader: (1)
 
Joined: Sep 2004
Posts: 11,975
Likes: 15
Default

If you really think big valves are important why don't you leave the hood closed.

Depending what your heads came off of the hollow/sodium filled valves that came in some 243 heads are highly sought after and even on the heads with solid valves some of the best results come from vendors who keep the stock valves.

Besides if they are already ported what do you think you would gain by putting a valve on that is bigger than what the bowl was ported for.
Reply
Old Feb 9, 2013 | 08:19 AM
  #4  
6togo's Avatar
Thread Starter
TECH Resident
iTrader: (13)
 
Joined: Feb 2012
Posts: 821
Likes: 0
From: Harford co. MD
Default

This is why i'm asking these questions not for you to come in my thread and be rude!
I'm fully aware if the valve sizes were increased the bowl would need some work and i did ask was it worth the gain!
I guess the only way to deterime what valves the 243's have currently would be to weigh them correct? If they turn out to be solid not hollow would that help changing to lighter valves i know not flow wise!
Reply
Old Feb 9, 2013 | 10:21 AM
  #5  
TurboMonte100's Avatar
Launching!
iTrader: (1)
 
Joined: Nov 2012
Posts: 201
Likes: 0
From: Central Indiana
Default

Those flows numbers posted are not bad at all, I'd say you have a good set of heads (reguardless of valve size). As already said, at this point any increase in flow will be small and the expence high.
Reply
Old Feb 9, 2013 | 10:27 AM
  #6  
batboy's Avatar
11 Second Club
iTrader: (6)
 
Joined: Feb 2005
Posts: 1,309
Likes: 2
From: middle of nowhere, Kansas
Default

Larger intake valves flow a little more, but at the expense of more mass. I say try what you got and see what happens.
Reply
Old Feb 9, 2013 | 12:16 PM
  #7  
96capricemgr's Avatar
11 Second Club
iTrader: (1)
 
Joined: Sep 2004
Posts: 11,975
Likes: 15
Default

I would guess weighing is the best way to ID your valves but really the hollow ones are only really worthwhile if looking to push the valvetrain limits with aggressive lobes, high rpm and trying to keep the spring reasonably light.
Reply
Old Feb 9, 2013 | 12:44 PM
  #8  
6togo's Avatar
Thread Starter
TECH Resident
iTrader: (13)
 
Joined: Feb 2012
Posts: 821
Likes: 0
From: Harford co. MD
Default

The cam i have it good to around 7k rpm and the lobes are not real aggressive(ED Curtis lobes)
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-1

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-2

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-3

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-4

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

 Verdad Gallardo
story-5

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-6

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-7

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-8

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-9

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo




All times are GMT -5. The time now is 08:51 PM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-4
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-5
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-6
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-7
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-8
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-9
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