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Discussion Starter #1
Do valve springs make a difference when putting in a solid flat cam. AFR says .550 max lift on their 1.45" 120# seat dual valve springs for a hydrolic. Do these limits apply to solid as well, or is it a different style spring. I want to go with a solid, but i dont feel like changing the springs for a few extra hp. And does .550 max lift mean that is the extreme limit or is that more of a buffer zone for them. I'm looking at a lunati vooddo cam(hydrolic) and the exhaust lift comes out to .560 with 1.6 rockers. Is that .010 over the limit gonna make a big deal. Thats like saying an elevator with a 1000 lbs max is gonna snap of the cables at 1002 lbs. Myabee i'm wrong.
 

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I would say .550 is what they guarrentee the springs to work with. You need to check them for the correct clearance no matter what they say. But slightly over over .550 would probably still work. I have never heard of a difference between a solid and hyd spring. I would think. 010 would still work, I doubt they cut it that close on tolerance. You should check them for clearance and coil bind before you run the engine.
 

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Solid Cam Valve Springs?

Hey Now. The spec sheet says to 550 lift. Then those springs will work on any cam lift up to 550. Just be sure to measure the seat pressure spring installed. Also make sure that the correct rocker ratio is used. 1.5 is stock and 1.6 can be used for small blocks. 1.6 used on a cam and spring that is 550 lift could stack the spring or crash valve into the piston. Just be sure to check and ask on this site or the cam manufacturer what they recommend. Sincerely, "Bill's" II :)
 

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Valvesprings

When building I like to check all the clearances, this leaves nothing to guess. In your case, piston to valve clearance, installed height, max lift, coil bind. It is possible to stack the sping with max lift if the installed height is incorrect. You have to check valvespring pressure/height at present. If heads are new, this SHOULD be as claimed.
Example: spring - 1.8"installed height @120lbs, coil [email protected] cam lift .570"

1.8"(installed)-1.2"(coil bind)=.600" possible lift before coil bind
same spring with incorrect installed height, say with .040 less, and that eats up any margine that you THOUGHT you had.
If you're only .010 over max lift, I can't see a problem as long as the installed height is correct.
I use an old solid lifter @ weak spring to check this thoroughly.
This can be done with heads on the car, if you want explanation just ask.

I hope that I've helped somewhat....:)
 

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There is a difference between a solid and hydraulic spring. The hydraulic has less seat pressure on it. You only set up at 85-95 lbs on a hydraulic and 120-150 on a solid. Also, you need to check your clearances before you start this puppy up. You don't need any banging around in there. Dave
 

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Discussion Starter #6
so it sounds to me that all my cam choices are possible, but which one do i
Pick:
COMP 274 EXTREME ENERGY 274/286 230/236 @50 .490/.490 (HYDROLIC)
COMP 274 EXTREME ENERGY 274/280 236/242 @50 .501/.510 (SOLID)
LUNATI VOODOO 276/284 233/281 @50 .504/.525 (HYDROLIC)
These are the 3 cam choises I've narrowed it down to. Will they will all make the same power give or take, I know the second 2 will probably out perform the first one, but they are on the upper limit of the valve springs. Now I know why way back when they refered to cams as 5/8 and 3/4 race cams. Way too many decisions to make now a days. We know too much for our own good.
 

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What heads do you have? What is your engine set-up and plans? I would look at flow of the heads and rpm range you will before deciding on the cam. You do not want to turn hydraulic rollers more than 6000 - 6200. You can but with no benefit.

That 236-242 cam sure will sound good at idle. I had one 520 lift and 1.6 's with the same duration. It was a dog off nitrous and very sluggish driving around town.... and was pulled quick. sure sounded good though. :rolleyes:

In my opinion..... If you are going to turn 6000 rpm's and have around 190 cc heads on a 350 to 383, I would run under 230 duration at .050. That way you can run a 3000 stall converter and be okay on the street. The engine will make around 450fwhp with 10.1 compression.

If the car is for the strip then that is a different story.
 

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Discussion Starter #8
I use afr 195 heads. The car for the most part is just for driving around town and track use. I'm leaning more and more to the comp xe 274 hydraulic. Seems to be the best of both worlds. I still have to pull the old cam out and see what the numbers are because I'm not sure what the specs are on it. I'm not gonna swap cams to go up one step. It idles nice at about 600 rpm and pulls about 17 hg vac so i dont think it is too agressive, but the car runs low 13's so sometimes I wonder if the cam is bigger than I think.
 

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I am running the Comp XS 268 solid in my car. It idles fine and pulls strong to over 6,000 rpm.
 

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Discussion Starter #10
Dan, how much does that wagon weigh, and what stall u use with that cam
 

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I just weighed it a couple of weeks ago. With the gas tank at 3/4 full and me out of the car it weighed 3,220#

I am running a modified stock converter. It is supposed to stall to 2,200-2,400 but I can never pedal it over 2,000. Car idles fine at about 850rpm. I'm sure it would go lower but I do not run a choke and it only take a couple of minutes for the car to idle even when cold, so I prefer to keep it a little on the higher side.
 
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