anyone know of a valve spring for stock pocket/ guide, good for .525 lift & 6500rpm?? theyre old #370 over the counter "turbo" style sbc heads with a comp cams 294s cam? if i take the valve lash into consideration its only .503 lift i think?? its been a long week and i'm confusing myself... installed height, coil bind, plus what ever thousands clearance i dont remember gives you max lift?? right??? just dont remember that minimum clearance to coil bind... grrr .040?? .050? .060???? if some one knew a spring that would work without machining the spring seat/guide this would be alot easier... haha thanks for any help guys!
I have a .477 lift cam and my suggestion is to ask the cam MFG..they will set you straight..use their shit, also cheap insurance..going with some one elses suggestion is dangerous..the manufacture of the cam has tested and done the R and D on this set up..go see what they say
thanks.... but comp cams wants you to go to a double spring and machine the guides and thats what i dont want to do... it was supposed to be a cheap build but they never end up that way??? oh well... i thought i had this all figured out but i've been away from the project for so long i dont remember anything, when i was a teenager i used to know all this stuff from memory.... how soon it starts!!
Trust me If thats what comp cams says needs to be done to run these..than any short cuts you take will just end up head aches for you. either do what is suggested, or choose a smaller lift cam
I would look into stock car companies, Speedway / Howards etc, Those guys all run large solid lift cam without spending too much $. You dont mention if you have screw in studs, with the seat pressure you need to run on a single spring I dont know how long a pressed in stud will last. http://www.speedwaymotors.com/images/charts/Chart-4509205.gif Heres a few Isky springs for SBC, dont know your OD, installed ht etc.
comp cams calls for an installed height of 1.750 @ 132pds and an open height of 1.250 @ 293pds (.500 lift) and are supposedly good to 8k rpm
I would agree with others that you need to talk with a single company and buy their stuff, or at least what they recommend. Or, work with a machine shop that is reputable for their recommendations on your specific engine. I run a 560 lift cam in mine and there is a lot of stuff done to ensure that those 7,000 rpm blasts don't end in disappointment. 525 lift is right at the edge of what can be done without some serious changes to the heads. A smaller cam might be a better choice if you are wanting to go cheap. Good luck with your project.
just got a set of speedway single with dampner that were good to something like 550 lift . stock diameter , won't fit a vortec guide boss..... i got a set of beehives for my nephews vortecs that were good to 560 or so , but they were something like 160 bucks vs the 25 for the speedways. brandon
correct me if i'm wrong but i think its not really even .525 lift after you take valve lash .022 into consideration its .503... add in a little more lash .025 and you got .500 go to .030 and you got a .495 lift cam not to far off the gm off road 1 cam which is .493/.512 with lash taken into consideration .486 lift this cam used gm z28 springs... with alot more duration & rpm in a 302 crossram motor i know modern lobes are more agressive than 60's cam technology but still... a valvetrain weighs what a valvetrain weighs... and 8k rpm capability on gm z28 springs? but 6500 is not attainable without double springs, because of .013 more lift... i dont see it even with modern lobes... theres only so far you can push a flat tappet cam without going to mushroom type lifters... i have no intention of going over 6500 and thats the chip that will be in the msd box... its not a roller cam... i just dont see it??? to me the 294s cam is a b/s cam... 60's muscle car grind practicaly otherwise i would have used it in a better motor
thats the reply i was lookin for thanks brandon i'll take a look at speedway... i'll give a little more on the total build its a large journal cast crank b/s 327 built from parts i couldnt walk past at swap meets, good std bore 350 2bolt block (free) $20 for 11:1 pistons.$25 fresh 10/20 327 crank (with bearings) 294s cam from another build that went roller before it was fired up, jackson gears (free) #370 "turbo" heads (free) intakes are optional; mt crossram, holley strip dominator, eddy torker, eddy torker2, eddy performer... the car was free its a rusty 55 chevy 2dr sedan shell, ford f100 axle for upfront $150, lexan side windows(free) new strait front fenders (free),cast iron t10, donor 57 chevy chassis with olds posi rear and 5.14 gears from my 57 chevy before i fell down the rabbit hole with that car (950hp blown bbc, tubbed 4link, caged, pretty much expensive & miserable on the street) i dont want to do not want to fall down the rabbit hole again with this car...
You seem to want someone to agree with you instead of taking the advice that's offered. Why ask if your set in your ways. Put it together.....if it blows up you'll know there was something "not right". Remember the old saying, "we don't have enough time to do it right, but we'll find enough time to do it over". Frank
I build a lot of 2 bbl circle track engines that by rule we have to run 1.260 springs stock dia. So there are a lot of springs that will fit you app.
lucky for me!! the right guy was on the job!! fab32 you've been a big help! your technical knowledge overwhelms me! never would i have thought of, put it together... if it blows up you'll know there was something (not right)" let me guess you "pay the man to do it" cause your too scared to do it yourself... thanks for the HELPFUL replies... later fella's i'm done here, speedway has what i need... thanks... and fab sorry, i usually try to keep things civil...but one good dig deserves another... later!
There are the "Z28" style stock dia spring available that have a taller installed height and will take that lift no problem... and they are pretty cheap. We use a ton of them for spec class engines.
I will agree with the Z28 springs... check with the roundy-round parts dealers, they should have what you need.
Call competition products and order there 98213 for $79.00 600 lift spring or the better polished spring 98215 $99.95.Your question is answered .
Don't forget to also check the following specs - Retainer underside to valve guide clearance with whatever seal you're using, 0.060" minimum. With your spring choice ensure they have an extra .060"+ at full lift till coil bind. Check this with the retainer, usually the dampner coil will bind first. Check for rocker slot to stud clearance at full lift, again allow extra space. For extra security invest in a set of 3/8" polylocks. Good luck.
Hey JJ88........do the simple thing...........put your engine together, with the plugs out and a breaker bar turn the engine over slow.....only have the valve lash set on #1 and all the pushrods removed from the rest of the engine. Turn your engine iver slowly and with a bright pinlight look at your springs really closely, keep turning....when they're almost all the way down (Full Lift), grab your feeler guages and start sliding .050 in there......if at any time you can't move the feeler.........STOP!!!!!!! If you get to full lift....leave it there....mount a dial indicator on your rocker arm.......set the indicator on -0-......and with a wrench, gently go as far as you can by hand......when it stops.....look at the number on the indicator. If your at at least 050 to 060......your safe. What I do is weld a long handle on the side of the intake and exhaust rockers.....that way I can check for coil bind and hitting..............
i have ran the z28 springs for 20 plus years now with only one failure,it took me about a half hour to replace the one broken spring. remember this is in a car that i beat the crap out of everytime i drive it . its not driven daily but it gets driven to the dragstip and ran hard,and also ran hard on the street. but i never need to spin it past 6000. the cam is a 525 lift solid with the bigger ratio rockers........in short the z28 springs will work fine....
You seem to want something for nothing. The reason you will need to do the seat and guide work is that every new spring has to be set up properly to work. Stock seats are not all the same. They have to be checked at assembly, too. When you change a spring, the question is if it has the correct installed height. If too short, you need longer valves or deeper seats. If to high, you need shims. To get the lift you want, first the springs need to be at the correct installed height, then they need to be able to compress that much without coil bind. Small wire springs don't have the seat pressure to avaoid valve float at rpm and big wire springs need the seats cut, THEN, if there would be no coil bind, you need to know if the retainer will hit your valve guide and seal. There needs to be about .080 safety margin here. Period. Are the people above saying you can get by one way or another wrong? Not for THEIR motor. What do they know about yours? Decking the block, milling the heads, head gasket choice, stud type, rocker type, pushrod length, grinding the tip of the valves, cutting the seats, all impact your set up. You deviated from stock when you took it apart and decided to change something. Now you need to custom build everything OR use a known good combination. Simple, really. Stop screwing around with the most sensitive part of your build and do it right. If you don't have the cash for proper set up, what makes you think you can afford all the damage you risk? Did you already know all this? Then why'd you ask? Didn't know all this? Why'd you choose a cam that clearly needed this work? Wow!
thanks screaming metal thats the EXACT answer i was looking for i couldnt remember the minimum clearance... saving to my note pad!!! i found a set of isky springs if installed at 1.750 they should be good for .550 lift, and pressures are where i need them as for everyone else that says if you dont spend money its "not right" just because the guy taking your money for overkill parts and machine work does not make it "neccecary" machinist gotta eat too... my motor will be "right" for what it is intended for... if it see's 6500 rpm it will be by mistake... its a CAST CRANK MOTOR... perhaps i worded my earlier posts wrong i was not asking if it could be done with a stock diameter spring...i was a little tired... it can be done... i was asking for clearances and if anyone knew of a good spring to use, to make my life easier... i guess somewhere along the line my questions were taken the wrong way... theres more than one way to skin a cat... after all the name calling and argueing this made my life harder and i should have just looked up the spec's myself
hey JJ88......most stock chevy early models can hit about .510 to .520 lift with no problem........now going that high while the engine running is another matter........... If your really low dollar......use can use 'used springs' off a hi-perf. chevy.......just clean them and look at them really careful.....also check their pressure to make sure they are no fatigued......... If you can shop around, there's no reason why you can't pick up a new set of springs that'll handle 550 safely and turn 6500 rpm withoutfloating for about 80 bucks........check out Summit and Jegs...........some of the cam grinders sometimes discontinue a line and will sell their extras really cheap................Keep the Faith!!!!!!!!!!!!!!
Theres 2 or 3 different springs that'll work fine, 'ultralloy, pacalloy and nicalloy' springs depending on which will get up to about .600 lift with 1.16 coil bind. When a cam gives lift, don't be subtracting any numbers from it, those are the same numbers that the spring mfgrs use as well. Hope you got long slot rockers. Last bit of advice, never ever design by committee. Some of these guys gave you good advice, some gave bad, some told you what you wanted to hear, there are a few of us who know the difference and we ain't sayin which is which. btw/ at that much lift it would be a good idea to check piston/valve clearance. Good luck, oj
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