I am building a pump gas 406 SBC with a 294s solid lift comp cam.I have decided to purchase a set of AFR 195 Elimators 64cc's prt#1034 they say the standard springs that come on them will handle a 600 lift cam.Jeg's are out of the heads untill march 15.I found them at another dealer for the same price as jegs and he can ship them right out.He says the 1.290 springs that comes on them will have to be upgraded for a price of $95.He says the adverised 600 lift is for a hydraulic cam and will not work on my solid lift cam.Comp Cams say i need a 130 seat,300 ld. open for the 294s.My builder says the standard springs without upgrade will work up to 6000 rpm's.I am confused.What would you do?
Help me on valve springs for AFR heads
shockers69
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I am building a pump gas 406 SBC with a 294s solid lift comp cam.I have decided to purchase a set of AFR 195 Elimators 64cc's prt#1034 they say the standard springs that come on them will handle a 600 lift cam.Jeg's are out of the heads untill march 15.I found them at another dealer for the same price as jegs and he can ship them right out.He says the 1.290 springs that comes on them will have to be upgraded for a price of $95.He says the adverised 600 lift is for a hydraulic cam and will not work on my solid lift cam.Comp Cams say i need a 130 seat,300 ld. open for the 294s.My builder says the standard springs without upgrade will work up to 6000 rpm's.I am confused.What would you do?
Shocker,
What you need to do is call AFR and get the spring specs on the springs that come on the heads. Then ... compare them to the Comp Specs or call Comp and ask them if the springs will work ok. Without knowing the actual seat pressures and spring rate of the springs that come on the heads, we would only be guessing, and that usually does not work well when building performance engines.
What you need to do is call AFR and get the spring specs on the springs that come on the heads. Then ... compare them to the Comp Specs or call Comp and ask them if the springs will work ok. Without knowing the actual seat pressures and spring rate of the springs that come on the heads, we would only be guessing, and that usually does not work well when building performance engines.
Find what spring is reccomended for the cam you have, you need to know seat pressure open pressure and coil bind, then cross that with the springs they supply, it's the only way you will know for sure, definitely don't go with a "sure they will be fine" answer.
I would look at a bare head and buy the parts you need unless you can get exactly what you want.
I would look at a bare head and buy the parts you need unless you can get exactly what you want.
Sean,Beat me to it Bill....
Back in 1967, I took a "dare" and took typing class in High School. Actually, I wanted to be the only one in with the girls
Turned out to be the best class I took that year (in more ways than one ! )
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I'll save you the phone call. Got the chart right here.
part#..OD.......Seat..........open.........bind..rate max lift
8000 1.54 225 @ 1.950 600 @ 1.250 1.155 550 .710
8002 1.55 170 @ 1.980 430 @ 1.430 1.200 475 .650
8003 1.56 250 @ 1.980 610 @ 1.280 1.160 515 .740
8004 1.29 150 @ 1.740 380 @ 1.160 1.010 397 .630
8016 1.55 140 @ 1.930 365 @ 1.380 1.140 410 .600
8017 1.29 135 @ 1.800 340 @ 1.230 1.050 360 .600
8019 1.27 155 @ 1.810 412 @ 1.210 1.080 428 .650 *these are the ones I got for a 232/239, .530/.550 hydraulic roller
8020 1.437 120@ 1.800 300 @ 1.250 1.090 325 .550
8021 1.64 250 @ 2.000 800 @ 1.250 1.070 645 .800
8022 1.64 320 @ 2.040 870 @ 1.190 1.150 645 .840
8023 1.58 235 @ 1.950 610 @ 1.250 1.170 535 .730
8031 1.625 255@ 1.950 633 @ 1.250 1.130 540 .750
Don't ask me which is the standard spring, I dunno
part#..OD.......Seat..........open.........bind..rate max lift
8000 1.54 225 @ 1.950 600 @ 1.250 1.155 550 .710
8002 1.55 170 @ 1.980 430 @ 1.430 1.200 475 .650
8003 1.56 250 @ 1.980 610 @ 1.280 1.160 515 .740
8004 1.29 150 @ 1.740 380 @ 1.160 1.010 397 .630
8016 1.55 140 @ 1.930 365 @ 1.380 1.140 410 .600
8017 1.29 135 @ 1.800 340 @ 1.230 1.050 360 .600
8019 1.27 155 @ 1.810 412 @ 1.210 1.080 428 .650 *these are the ones I got for a 232/239, .530/.550 hydraulic roller
8020 1.437 120@ 1.800 300 @ 1.250 1.090 325 .550
8021 1.64 250 @ 2.000 800 @ 1.250 1.070 645 .800
8022 1.64 320 @ 2.040 870 @ 1.190 1.150 645 .840
8023 1.58 235 @ 1.950 610 @ 1.250 1.170 535 .730
8031 1.625 255@ 1.950 633 @ 1.250 1.130 540 .750
Don't ask me which is the standard spring, I dunno
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So looking at your 130 seat, 300 open, and that cam is less than .550 lift,
8020 is no go
8004, 8016, or 8017 would work. I like a small diameter spring, nice and light, maybe some titanium retainers to go with it? And what's this 6000 rpm stuff? a 294S? You better spring for 7k.
I like the 8004
8020 is no go
8004, 8016, or 8017 would work. I like a small diameter spring, nice and light, maybe some titanium retainers to go with it? And what's this 6000 rpm stuff? a 294S? You better spring for 7k.
I like the 8004
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OK Comp says the cam requires a 130 seat and a 300 open.I call AFR they say the springs are good for 324 open and 135 seat.Does that mean they will work?I am in the dark on this valve geometry stuff.
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Those numbers would work, yes for sure. Which spring is it?
Seat pressure is eas, it's listed directly in the chart @ the installed ht.
Open pressure is harder to figure. They list it at what certainly appears to be an arbitrary number. you need to know what your cams max lift is. Subtract that from the installed ht to get the spring ht at your cams max lift. Then compare that to the open ht and pressure they list, or better yet, do the math with the spring rate, which is in lbs per inch.
Take the 8017 spring. 135 lbs @ 1.8" If we do it the easy way and figure a .5" lift cam, the rate is 360 lbs per inch. Since .5" lift is half an inch, take half the spring rate (180) and add it to the seat pressure (135) to come up with 315 lbs @ 1.3" with a .5" lift cam.
I don't know the gross lift of a 294s offhand, and the math is kinda complicated for this time of night, but hopefully you get the idea.
Seat pressure is eas, it's listed directly in the chart @ the installed ht.
Open pressure is harder to figure. They list it at what certainly appears to be an arbitrary number. you need to know what your cams max lift is. Subtract that from the installed ht to get the spring ht at your cams max lift. Then compare that to the open ht and pressure they list, or better yet, do the math with the spring rate, which is in lbs per inch.
Take the 8017 spring. 135 lbs @ 1.8" If we do it the easy way and figure a .5" lift cam, the rate is 360 lbs per inch. Since .5" lift is half an inch, take half the spring rate (180) and add it to the seat pressure (135) to come up with 315 lbs @ 1.3" with a .5" lift cam.
I don't know the gross lift of a 294s offhand, and the math is kinda complicated for this time of night, but hopefully you get the idea.
Sean,
Back in 1967, I took a "dare" and took typing class in High School. Actually, I wanted to be the only one in with the girls
If I had someone like you to explain that logic to me back in high school I wouldn't be doing the "two finger peck" right now I figured back then why would I ever need that? (of course I hadn't thought about the girls..) Now as I respond to multiple emails and write questions regarding prints every day at work I think I might have been wrong.....
Shocker, it appears you would be OK, but I really reccomend getting the exact specs from the springs they supply and calling comp with the info. This is an area you want to be 100% sure, if not for longevity of the springs, but especially so you don't wipe a lobe on your cam and have to tear down the entire motor. Better to err on the side of caution here, IMO.
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JIM are the 8000 numbers Comp Cam spring numbers?I think i understand what happens if the spring pressure is too high,you wipe out a cam lobe.But if spring pressure is too low what happens?
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If the spring pressure is too low, you float the valves, an event that can wipe out a lobe much faster than simply having high pressure.
Most of the studying I've been doing lately has related to hydraulic rollers, and the current wisdon seems to be LOTS of spring pressure, minimum wieght on the valve side, and the strongest pushrods you can afford.
The part numbers I listed are AFR's numbers, right off the package that came with my new heads. They do not tell, at least not in the manual that ships with the heads, where these springs come from.
That 294S is a lot of cam. If you are really intending to build a 6000 rpm engine, you should rethink that cam choice. If that's your cam, you need to build for 7000 rpm.
Most of the studying I've been doing lately has related to hydraulic rollers, and the current wisdon seems to be LOTS of spring pressure, minimum wieght on the valve side, and the strongest pushrods you can afford.
The part numbers I listed are AFR's numbers, right off the package that came with my new heads. They do not tell, at least not in the manual that ships with the heads, where these springs come from.
That 294S is a lot of cam. If you are really intending to build a 6000 rpm engine, you should rethink that cam choice. If that's your cam, you need to build for 7000 rpm.
Springs should match the Cam makers specifications.
It really is the best way.
Head makers have NO CLUE as to what cam you'll run or the harmonics of the valvatrain from the lobe, lifter, pushrod etc but the Cam maker does. Tossing on a Generic HYD/Solid lifter spring good for .600 lift, or Roller springs means as much as the power rating of a 200 watt car stereo head unit, which uses a 10 amp fuse. It means Nothing.
If the supplied springs are a match, you're golden, if not, pawn them off and get the right stuff.
It really is the best way.
Head makers have NO CLUE as to what cam you'll run or the harmonics of the valvatrain from the lobe, lifter, pushrod etc but the Cam maker does. Tossing on a Generic HYD/Solid lifter spring good for .600 lift, or Roller springs means as much as the power rating of a 200 watt car stereo head unit, which uses a 10 amp fuse. It means Nothing.
If the supplied springs are a match, you're golden, if not, pawn them off and get the right stuff.
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I'm cautious with AFR's springs, even if they meet the specs for the cam; I've heard of 2 motors with broken spring issues, one failed while on the dyno. (hence why I didn't use the ones that came with my afr's) Google it too, sounds like there are quite a few issues out there on afr valve springs. Some guys haven't had problems to though, it seems like the problems show up with higher lift cams or racing applications.
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Well i am broke now.I ordered the AFR 195's 65cc's #8017 springs straight plug heads from Competition Products.I also ordered the 294s cam and lifters from Summit.I am using heavy TRW forged -15cc pistons,Speed Pro molly rings w/a 26 gap on top ring and a 22 on second ring.stock 400 rod w/ARP bolts,ARP main studs,750 Holley DP,Performer RPM intake,Doug's 1 3/4" full length headers,Th350 trans.,410 rears,3200 RPM stall converter.Will this thing run in the mid 7's in 1/8 mile?I have a Super Power Shot nitrous kit that i use the 150 jets,I also have a MSD timing retarder. Will it have a choppy idle?PS it is giong to kill me to drill steam holes in these high dollar heads.
For crying out loud man, don't drill 'em then...
. Seriously, with the specs you are showing for your build you definitely don't need the steam holes.As for mid 7's, if you can make the rest of the package work (chassis) there should be no reason you can't. Just get that thing tuned right and get t to hook and it should run real good. Add a 150 shot and you should see 6's if it all works together.
As for a choppy idle, definitely with that cam. That cam is on the big side for your combo IMO but it should work. Good luck with it :thumbsup:
Keep us posted how it runs at the track when you get it done. Its pretty similar to my combo but you should make more top end power. Mine has run 7.65 in the 1/8 with 0 tuning and 3.55's rear gears. I also have the 294S here in the box but have always wondered if it would pick up over my current cam. Please post your times when you get it going!
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