Cantedvalve 128 Report post Posted November 3, 2018 I was looking at camshafts today because, you know, who doesn’t? Anyway, I was looking at the recommended springs and retainers for this cam. The springs had an OD of 1.514, but the retainers were 1.450. I was under the impression that retainers should match the OD of the springs. Assuming I am wrong, what are the steps to selecting a retainer for a given valve spring? Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted November 3, 2018 The same retainer will be used for more than one spring O.D.. The retainer O.D. often doesn't match the spring O.D. My springs have a 1.5" O.D. and the correct retainers listed by the spring mfg. have a smaller O.D. I don't remember exactly, but somewhere in the range of 1.450 O.D. I think one important issue with spring retainers, is that the spring I.D. is located and held in place so the top of the spring will not walk. I'm sure somebody hear knows more about this topic than me. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted November 3, 2018 Spring cups to retain the bottom are also sometimes required. Quote Share this post Link to post Share on other sites
BuckeyeDemon 211 Report post Posted November 3, 2018 sometimes the spring catalog will group associated retainers with the valve springs. spring cup/locators are needed for aluminum heads so they don't eat up the soft aluminum. iron general can take it. locators/cups are also needed in if you use a smaller diameter spring than the spring pocket in the head was designed for. you should also consider your valve length when choosing a spring. it could impact your selection of a retainer or the spring. Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 3, 2018 Okay... so here is another question. If the camshaft lift and type dictate the springs to be used, should a split pattern cam have two different springs? So my current cam is a .536/.562 hydraulic flat. In theory, should I be looking for a spring with a slightly taller open height for the intake, or put another way, a slightly shorter open height for the exhaust? I know the difference isn't huge, but if you have to buy springs anyway... Quote Share this post Link to post Share on other sites
BuckeyeDemon 211 Report post Posted November 3, 2018 20 minutes ago, Cantedvalve said: Okay... so here is another question. If the camshaft lift and type dictate the springs to be used, should a split pattern cam have two different springs? So my current cam is a .536/.562 hydraulic flat. In theory, should I be looking for a spring with a slightly taller open height for the intake, or put another way, a slightly shorter open height for the exhaust? I know the difference isn't huge, but if you have to buy springs anyway... I personally think it's in the noise. if you look at comp's dual pattern cams, they don't specify two different springs (and I don't have two different springs in mine with lobes that have two different lifts). I guess if you really wanted you could shim up the valve with the less lift. Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 4, 2018 yeah I have a dual pattern cam too, and best of my knowledge same springs. I was just curious. I am guessing hard code racers might, but for street performance there is probably no point. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted November 4, 2018 Basically springs are setup with shims as needed to have the correct seat load, open load, and no coil bind at maximum lift with usually no less than 0.060" clearance between coils at maximum lift. Also need to make certain the retainer doesn't contact the valve seal at maximum lift. I've seen 0.060" and 0.100" values for that minimum clearance. On OEM small block Ford heads there are no spring pockets in the heads to locate the spring O.D. Instead there is a shoulder at the base of the guide to locate the spring I.D. Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 4, 2018 Which is why you have to machine the spring seats for dual springs. I spent all afternoon reading up. I’m planning my next engine (351C, always) and I was looking into a roller cam. I think I have all the short block parts and valve train parts selected, just need to decide what heads to use. Either the 2V I have now or some Aussie 302C heads if I can get my hands on some. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted November 4, 2018 2 hours ago, 1969_Mach1 said: Basically springs are setup with shims as needed to have the correct seat load, open load, and no coil bind at maximum lift... ...with usually no less than 0.060" clearance between coils at maximum lift. On OEM small block Ford heads there are no spring pockets in the heads to locate the spring O.D. Instead there is a shoulder at the base of the guide to locate the spring I.D. yup. many people building high perf engines set the clearance at .050". the less clearance there is, the less spring surge there will be. actually, the 271 hi po heads have pockets but that's the only one. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted November 4, 2018 2 hours ago, Cantedvalve said: Which is why you have to machine the spring seats for dual springs. I spent all afternoon reading up. I’m planning my next engine (351C, always) and I was looking into a roller cam. I think I have all the short block parts and valve train parts selected, just need to decide what heads to use. Either the 2V I have now or some Aussie 302C heads if I can get my hands on some. Not always. I don't know everything about 351 clevos but i know a boat load and can help you if you want. Dan Jones, Tim Meyers, and George Pence are also very knowledgeable and more so than I am. Meyers also stocks some special cam bearings for them. As far as high perf heads go, the chi's are overall one of the best, but afd and scott cook and trick flow also make some. If it was mine and i was going to flog it hard, i would do the lifter bore mod and main journal oiling mod. I would also only install the front cam bearing .005" deep to minimize the amount of oil loss from the large oil hole in the block there. I would also block off the t stat bypass plate then drill around a 1/16" hole in it then use a windsor style t stat. In case you didn't know, the aussie heads have a small combustion chamber, so you need get pistons that will give you the correct compression for your app. Also, a roller cam is overkill for those heads unless you port the bejesus out of them. POWER HEADS sells the aussie clevo heads and also sells a ported version. http://www.powerheads.com/heads.html As far as the oil pump goes, if you use a stock mellings pump, you should hone out the bypass bore slightly then sand the bypass piston lightly with water or wd40 and some 800 grit sand paper but it is easier just to buy a blueprinted pump.. https://www.tmeyerinc.com/ Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 4, 2018 That's the nice thing about the Aussies - 2V ports, 4V quench chambers. Quote Share this post Link to post Share on other sites
