General Tech Ask model specific questions in the appropriate category below. All other general questions within.

oversized valves?

Thread Tools
 
Search this Thread
 
Old Mar 7, 2005 | 05:19 PM
  #1  
mkspeed26's Avatar
mkspeed26
Thread Starter
5th Gear Member
 
Joined: Dec 2003
Posts: 2,392
From: Rochester, NY
Default oversized valves?

well here's the plan for the my 351W. forged flat top pistons, edelbrock performer rpm air gap manifold, holley 650 carb, edelbrock 226/236 @.050 cam (about .500 lift)and matching valve spring kit. im going to port and polish the heads, but i was wondering if putting in larger valves would also be a good option. i got a quote for $10 labor per cylinder and valves would be about $9 each. that would end up about $225. i was wondering if putting in oversized valves is a good idea with the way the rest of the engine is. i dont have the money for new heads and i figured the stockers would be a little small.
Old Mar 7, 2005 | 06:58 PM
  #2  
vfast's Avatar
vfast
I ♥ Acer
 
Joined: Jul 2003
Posts: 11,394
From:
Default RE: oversized valves?

if you can do it for 225 you better hurry before they wise up....by all mean do it..it will unshoud the valve but I would buy servere duty valve these have a cutback of the stem it lightens up the valve and it flow about 155 more..so it's a win-win..also get a 5 angle vale job....don't bother one to much of a polish on the intake side
Old Mar 7, 2005 | 07:39 PM
  #3  
import slayer's Avatar
import slayer
3rd Gear Member
 
Joined: Nov 2004
Posts: 807
From:
Default RE: oversized valves?

I agree with Vfast. Don't polish the intake side because the rough surface help mix the air/fuel charge. You might also want to look at the COMP CAMS XE series cams.
Old Mar 7, 2005 | 11:48 PM
  #4  
luckythirteen13's Avatar
luckythirteen13
6th Gear Member
 
Joined: May 2004
Posts: 9,092
From: las vegas, nv
Default RE: oversized valves?

i agree...go for it. $225 is a deal
Old Mar 8, 2005 | 12:26 AM
  #5  
5.0mustang5speed's Avatar
5.0mustang5speed
I ♥ Acer
 
Joined: Oct 2004
Posts: 477
From:
Default RE: oversized valves?

10 a head....are you sure they didt mean 10 hour per head plus parts...
Old Mar 8, 2005 | 01:42 PM
  #6  
vfast's Avatar
vfast
I ♥ Acer
 
Joined: Jul 2003
Posts: 11,394
From:
Default RE: oversized valves?

no he means 10.00 for intake and exahust on each cly about 80.00
Old Mar 8, 2005 | 05:07 PM
  #7  
mkspeed26's Avatar
mkspeed26
Thread Starter
5th Gear Member
 
Joined: Dec 2003
Posts: 2,392
From: Rochester, NY
Default RE: oversized valves?

well, after some more parts searching i changed around the combo a little. instead of edelbrock cam stuff im gonna get a crane cams saturday night special kit. cam specs are 296/300 advertised duration with .520/.526 lift. also comes with valve springs and retainers. that should give em a lot more power. also im gonna get a edelbrock EPS 800 carb.

think 2.02 intake and 1.88 exhaust will be good? and yes, that is $10 labor per cylinder. i have a deal with them cause im doing it through the school and they give us discounts.
Old Mar 8, 2005 | 09:59 PM
  #8  
vfast's Avatar
vfast
I ♥ Acer
 
Joined: Jul 2003
Posts: 11,394
From:
Default RE: oversized valves?

ok the carb is too big and you can't 1.88 exhaust valve in the head you might want to go with 1.60..do use those undercut valve from manley that cam has alot of duration what is the C/L of the cam?
Old Mar 8, 2005 | 10:42 PM
  #9  
angcobra's Avatar
angcobra
4th Gear Member
 
Joined: Nov 2004
Posts: 1,724
From:
Default RE: oversized valves?

I would agree, carb to big, can only use 1.6 exhaust valves, and the duration on the cam is way to long to have any vacuum.
Old Mar 8, 2005 | 10:54 PM
  #10  
mkspeed26's Avatar
mkspeed26
Thread Starter
5th Gear Member
 
Joined: Dec 2003
Posts: 2,392
From: Rochester, NY
Default RE: oversized valves?

here is the link for the cam specs >>> http://www.cranecams.com/index.php?s...62&lvl=2&prt=5 . i will put in 1.6 exhaust valves instead of the 1.8 . i just guessed on what size would be good. if 800 is too much, then what size do u recommend? about the vacuum- if i run into a problem with too low vacuum would a vacuum reservoir fix it?

thanks a lot for the help. im still a youngin (17, im not even legal!) and have a lot to learn still. it is a very ambitious project and can't wait to prove all the import f*ckers in town that i can do it!



All times are GMT -5. The time now is 08:21 PM.