Hungry for more valvespring info: Read this!
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From: RogersAr
Originally Posted by fade 2 black
If you can shim the springs without compromising coil bind then that will work.
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From: Plymouth, MI
Originally Posted by 69Roadster
Good find. I can buy that, lbs/inch^2 * inch^2 = lbs.
So my intake valves are 1.84". That gives me an area of 2.66 inch^2 (3.14*radius^2). Say I'm running 20psi... that means the force on my springs is 53 lbs.
Guess the question now is how much extra force do you need to keep a valve shut when there is 53lbs of force on it? Is 54#s enough? 70? 120???
Could be argued that if you had 74#s stock to keep it shut and you added 50#s trying to open it, that you'd then need to add 50#s to the 74 to get you back to stock performance right? Probably not as straight forward as that though
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EDIT: On second thought... Using a stock valve size and stockish boost of 8psi... force would be 19#s or 74 - 19 = 55#s keeping the valve closed. Sooo to get stock like performance with larger valves and 20psi I'd need 55 + 53 = 108# springs? Sound reasonable??
So my intake valves are 1.84". That gives me an area of 2.66 inch^2 (3.14*radius^2). Say I'm running 20psi... that means the force on my springs is 53 lbs.
Guess the question now is how much extra force do you need to keep a valve shut when there is 53lbs of force on it? Is 54#s enough? 70? 120???
Could be argued that if you had 74#s stock to keep it shut and you added 50#s trying to open it, that you'd then need to add 50#s to the 74 to get you back to stock performance right? Probably not as straight forward as that though
.EDIT: On second thought... Using a stock valve size and stockish boost of 8psi... force would be 19#s or 74 - 19 = 55#s keeping the valve closed. Sooo to get stock like performance with larger valves and 20psi I'd need 55 + 53 = 108# springs? Sound reasonable??
Going to a spring that can follow aggressive cam profiles should also allow you to run higher boost pressures.
BTW, you'll have to use the backside exposed area of the valve (seat inner diameter minus the valve stem) not the face diameter. The backside is the area that sees the pressure.
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From: Auburn Wa
Originally Posted by 69Roadster
Hmmm... sounds reasonable.
What are the downsides to solid lifters? Would you have to adjust them frequently?
What are the downsides to solid lifters? Would you have to adjust them frequently?
I never did anything else with my rockers after that....I can tell now they are made wrong and if you ran them with anything other than a stock spring the adjusters would break. So mine are on the shelf...maybe one day I'll call SSS and ask them if they need a good paper weight.
I decided to try a 4V with as many stock parts as I can run...except cams, valves and springs.
Dale
PS.....to answer your second question..YES...I think initially there would be a seating in period that would require several adjustments. When I took mine apart after only a few miles some had opened up and some had closed up a bit so you would have to chase them for an undetermined amount of time.
PSS....oh and one more thing....even at 22/23 lbs of boost it felt like it would rev to the moon...I could see shift points over 6000 rpm with the right cams, which I think would be a big boost in power.
Last edited by Bad as L; Jan 10, 2006 at 04:56 PM.
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From: Auburn Wa
Here is some more reading material: http://forums.modulardepot.com/showt...threadid=75182
And: http://www.mustang50magazine.com/tec...es/index1.html
I don't know why I posted the Yates article other than I thought it was funny that the only part in his engine that is a deep dark secret is the valve springs.
You can go to Hardcore50 or Turbomustangs or Modularfords and do a search and probably find 10 good valve spring posts....my point is this is not something new. Why is the Lightning community stuck in the dark ages ??? Sorry don't know that either....but if you look around there are other places you can get an education...not just here.
Dale
PS....the moddepot thread is a fun one....you have to wade thru the idiots and the cheerleaders but at the end it will be worth it.
And: http://www.mustang50magazine.com/tec...es/index1.html
I don't know why I posted the Yates article other than I thought it was funny that the only part in his engine that is a deep dark secret is the valve springs.
You can go to Hardcore50 or Turbomustangs or Modularfords and do a search and probably find 10 good valve spring posts....my point is this is not something new. Why is the Lightning community stuck in the dark ages ??? Sorry don't know that either....but if you look around there are other places you can get an education...not just here.
Dale
PS....the moddepot thread is a fun one....you have to wade thru the idiots and the cheerleaders but at the end it will be worth it.
Last edited by Bad as L; Jan 10, 2006 at 05:26 PM.
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From: The People's Republic of Los Angeles
Originally Posted by Bad as L
....the moddepot thread is a fun one....you have to wade thru the idiots and the cheerleaders . . .
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From: Northern, California
Originally Posted by 69Roadster
Had another thought in addition to my basic math...
What about pressure in the cylinder??? Doesn't it want to force the valve shut? I mean if there wasn't positive pressure then exhaust would be sucked in instead of pushed out right? Wouldn't that mean a 54# spring, with the cylinder pressure behind it, would keep the valve closed even with 53# of boost force trying to open it???
Man... it's complicated... glad I'm an electical engineer, electrons are easy.
What about pressure in the cylinder??? Doesn't it want to force the valve shut? I mean if there wasn't positive pressure then exhaust would be sucked in instead of pushed out right? Wouldn't that mean a 54# spring, with the cylinder pressure behind it, would keep the valve closed even with 53# of boost force trying to open it???
Man... it's complicated... glad I'm an electical engineer, electrons are easy
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From: Northern, California
As Dale said: My experience with solid lifters was bad. Went through three sets (revisions) along with one set of aluminum rockers. The last set ruined a very expensive set of heads. I now have hydraulics. I wanted to use them to rev the engine (+6000 rpm), not because of high boost. By the way the hydraulic lifters I now run are out of a SVT Focus. See if anyone knows why.
Last edited by Calightnin; Jan 13, 2006 at 01:35 PM.
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From: The People's Republic of Los Angeles
Originally Posted by Calightnin
Ding! You are correct. Maybe there is a mechanical engineer in you.
Or something.
I guess the question is how much pressure is there really on the face of the intake valve and when?
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From: Mansfield, TX
You guys are missing that you need a certain amount of closed pressure on the valve, including the exhaust valve to prevent chatter, and the valve bouncing on the seat. Jim mentioned that early on in this thread. Look at the closed force on a 5.4 NA motor with the same cams to determine what the starting point would be.
For a supercharged vehicle, On the exhaust side this might not need to change much until you run a more agressive cam, but the intake would need to have a higher seat pressure to over come the boost condition, bigger valves, etc.
For a supercharged vehicle, On the exhaust side this might not need to change much until you run a more agressive cam, but the intake would need to have a higher seat pressure to over come the boost condition, bigger valves, etc.
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From: McDonough, GA
Originally Posted by Calightnin
I now have hydraulics. I wanted to use them to rev the engine (+6000 rpm), not because of high boost. By the way the hydraulic lifters I now run are out of a SVT Focus. See if anyone can knows why.
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From: Houston, Tx
Originally Posted by adrenalinowner
what i love about reading you post jim is how deep you dig the hole. first you try and tell everyone that you need to run big *** valve springs to make more power because of valve float. valve float doesnt happen in ohc vehicles, valve bind does and just becuase your parter in crime thats trying to sell blowers agrees with you doesnt mean its true. you need to stop snowballing everyone into thinking that valvesprings are going to gain them hp in stock or even mildly boosted trucks.
then you move on to and state bs about prostock apps and how they change springs every three runs, they dont they check valve lash every run and adjust it, if they need to replace a spring, guess what bud they change the freakin motor out.
next you move onto ultrasonic cleaners and you say there are only a few of them in the county. tell you what everyone call this number and ask for chris k, he will tell you that he has sold 13 of them last month alone and that he has sold 50+ last year.. 443-790-3853. they have been out for years dumbass.
most of you are morons for believing everything that comes out of nj. try checking out information for yourself or god forbid you pick up a book and read about something that your going to spend your hard earned money on. of course the dyno numbers will show an increase if you buy the new springs and have them installed by jdm because you will be on their dyno and they can manipulate that anyway they see fit and make you happy but whene you take it to the track and dont see an improvement who you gonna cry to? You wont becuaese you will be ot imbarrrassed.
warren johnson would kick you *** for mentioning him jim.
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then you move on to and state bs about prostock apps and how they change springs every three runs, they dont they check valve lash every run and adjust it, if they need to replace a spring, guess what bud they change the freakin motor out.
next you move onto ultrasonic cleaners and you say there are only a few of them in the county. tell you what everyone call this number and ask for chris k, he will tell you that he has sold 13 of them last month alone and that he has sold 50+ last year.. 443-790-3853. they have been out for years dumbass.
most of you are morons for believing everything that comes out of nj. try checking out information for yourself or god forbid you pick up a book and read about something that your going to spend your hard earned money on. of course the dyno numbers will show an increase if you buy the new springs and have them installed by jdm because you will be on their dyno and they can manipulate that anyway they see fit and make you happy but whene you take it to the track and dont see an improvement who you gonna cry to? You wont becuaese you will be ot imbarrrassed.
warren johnson would kick you *** for mentioning him jim.
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