Camshaft install tips and tricks
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[[File:Combo worn cam lifter.jpg|thumb|450px|'''This''' is what has to be avoided!]] | [[File:Combo worn cam lifter.jpg|thumb|450px|'''This''' is what has to be avoided!]] | ||
==Disclaimer== | ==Disclaimer== | ||
| − | Use this list as a guideline so that you remember to check all these things when installing a new flat tappet camshaft. This list is not gospel, and if the manufacturer of the camshaft you're using recommends procedures that differ from what is shown here, use the manufacturer's recommendations instead. | + | {{!}}Use this list as a guideline so that you remember to check all these things when installing a new flat tappet camshaft. This list is not gospel, and if the manufacturer of the camshaft you're using recommends procedures that differ from what is shown here, use the manufacturer's recommendations instead. |
| − | ==Mistakes that may | + | ==Mistakes that may cause failure of a flat-tappet camshaft and lifters == |
===Cleaning=== | ===Cleaning=== | ||
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'''3. Failure to properly massage an extreme pressure lubricant such as molybdenum disulphide into the pores of the metal on all lobes and lifter faces.''' | '''3. Failure to properly massage an extreme pressure lubricant such as molybdenum disulphide into the pores of the metal on all lobes and lifter faces.''' | ||
| − | Molybdenum disulphide will actually bond with the metal and give maximum protection to the lifter crown/lobe. Use the 'moly' lube on the distributor gear, cam lobes and the lifter foot that contacts the lobe only- '''not''' the bearing journals, and '''not''' the sides of the lifters. Engine oil | + | Molybdenum disulphide will actually bond with the metal and give maximum protection to the lifter crown/lobe. Use the 'moly' lube on the distributor gear, cam lobes and the lifter foot that contacts the lobe only- '''not''' the bearing journals, and '''not''' the sides of the lifters. Engine oil can be used on the lifter bores and lifter sides, and the pushrod cups of the lifters. |
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*[http://www.zddpforum.com/forum/ ZDDP forum] | *[http://www.zddpforum.com/forum/ ZDDP forum] | ||
<br style="clear:both"/> | <br style="clear:both"/> | ||
| + | |||
| + | It is a very good idea to change the oil and filter after the initial cam break in period. Use another dose of ZDDP. This oil and filter can remain for the next 500 miles. After that, change the oil and filter again. Add ZDDP unless the motor oil that's being used contains sufficient quantities for a flat tappet engine. | ||
| + | |||
| + | Resume a normal maintenance routine after the first 500 miles. | ||
===Installation=== | ===Installation=== | ||
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===Checking clearances=== | ===Checking clearances=== | ||
| − | '''Note:''' More info on checking clearances at | + | '''Note:''' More info on checking clearances at '''[[Valve train points to check]]'''. |
'''8. Failure to check for valve spring coil bind at max lift.''' | '''8. Failure to check for valve spring coil bind at max lift.''' | ||
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'''16. Failure to have everything ready for the motor to fire on the first few turns.''' | '''16. Failure to have everything ready for the motor to fire on the first few turns.''' | ||
| − | Fully charged battery, good starter, known-good carburetor with full fuel bowl, source of fuel to the carburetor to allow minimum 20 minutes of uninterrupted running. Ignition timing set. Warning: no grinding on the starter! | + | Fully charged battery, good starter, known-good carburetor with full fuel bowl, source of fuel to the carburetor to allow minimum 20 minutes of uninterrupted running. Ignition timing set. Warning: no grinding on the starter! |
===Pre-lube engine oil system=== | ===Pre-lube engine oil system=== | ||
| − | The lifters can be dipped into a container of oil but unless the manufacturer's instructions tell you otherwise, there's no need to pump hydraulic lifters up before installing them. There are some exceptions to this. For instance Rhodes lifters DO recommend their " | + | The lifters can be dipped into a container of oil but unless the manufacturer's instructions tell you otherwise, there's no need to pump hydraulic lifters up before installing them. There are some exceptions to this. For instance Rhodes lifters DO recommend their "<i>original</i>" lifters be pumped up prior to installing, then for them to be adjusted to 3/4 of a turn, or so the lifter cup is about 1/16" below the retainer. |
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Used lifters should only be used on the very same cam, in the very same block, and in the very same positions they were removed from. Chances that the lifter bores will be machined on the very same angles on a different block as the block the lifters came out of are about equal to you hitting the lottery. If you purchase a used flat tappet cam from a swap meet or yard sale, plan on using it for a doorstop. New lifters should not be used on an old cam, either. Given the reasonable cost of a new cam and lifter set (~$100 ca. 2012), vs. the cost of cleaning and repairing the damage done by a failed cam and lifters, the choice to use new parts is obvious. | Used lifters should only be used on the very same cam, in the very same block, and in the very same positions they were removed from. Chances that the lifter bores will be machined on the very same angles on a different block as the block the lifters came out of are about equal to you hitting the lottery. If you purchase a used flat tappet cam from a swap meet or yard sale, plan on using it for a doorstop. New lifters should not be used on an old cam, either. Given the reasonable cost of a new cam and lifter set (~$100 ca. 2012), vs. the cost of cleaning and repairing the damage done by a failed cam and lifters, the choice to use new parts is obvious. | ||
| + | |||
| + | |||
| + | '''19. Failure to observe the lifters and pushrods turning with the motor running.''' | ||
| + | If the lifter is not turning, the cam lobe is hitting on the same spot on the lifter every revolution and it won't be long until the lifter yields and then takes the lobe out with it. All lifters and all pushrods must be turning for successful engine operation. | ||
==Lubrication== | ==Lubrication== | ||
That pencil-point of contact between the camshaft lobe and lifter crown is under somewhere between 250,000 and 300,000 pounds per square inch of pressure, so it should come as no surprise that extreme pressure lubrication is required, especially at break in where the contact point between lobe and lifter is irregular. The break in grease applied to the bottoms of the lifters and to the cam lobes is all the lubrication there is during the initial 5 to 10 seconds of operation, until motor oil reaches the interface. | That pencil-point of contact between the camshaft lobe and lifter crown is under somewhere between 250,000 and 300,000 pounds per square inch of pressure, so it should come as no surprise that extreme pressure lubrication is required, especially at break in where the contact point between lobe and lifter is irregular. The break in grease applied to the bottoms of the lifters and to the cam lobes is all the lubrication there is during the initial 5 to 10 seconds of operation, until motor oil reaches the interface. | ||
| + | |||
| + | ===Comp Cams's position on break-in additive and nitriding=== | ||
| + | <blockquote> | ||
| + | ''"Due to federal legislation, motor oils no longer contain certain anti-scuffing agents that played a critical role in flat tappet camshaft break in. While incorrect valve spring pressure and not following proper break-in procedure are often the culprits, the changes in oil formulation have brought about a need for additional steps to be added to the break-in process.'' | ||
| + | <br><br> | ||
| + | ''COMP Cams has two ways to ensure proper break-in of flat tappet cams. COMP Cams Engine Break-In Additive (part #159) ensures that the camshaft will have the lubricants that it needs to seat the camshaft journals and lobe/lifter surfaces. This lubricant is poured into the engine crankcase after the camshaft and lifters have been coated with the initial break-in lubricant (molybdenum disulphide) supplied with the camshaft.'' | ||
| + | <br><br> | ||
| + | ''Another option for increasing flat tappet cam longevity is nitriding. Recently COMP Cams invested in a nitriding machine, the first of its kind owned by a major U.S. aftermarket camshaft manufacturer. Nitriding actually hardens the surface of the camshaft and tappet face by injecting nitrogen “needles” into the metal. The result is an ultra-hard surface on the face of the camshaft lobes and lifter face, which greatly improves the performance and break-in process for flat tappet cams. This process is an additional charge for COMP Cams camshafts, but for many extreme duty applications, it virtually ensures proper break-in and increased durability."'' | ||
| + | </blockquote> | ||
| + | |||
| + | George "Honker" Striegel (owner of Clay Smith Cams) said the following in an article on Ford inline 6 engines (to be taken with a grain of salt): Lets talk about that special treatment Comp Cams offers, for an additional $110 dollars. It's true that nitriding a cam raises the Rockwell hardness to 55-60, however they do nothing to increase the hardness of their lifters and most everyone will agree that it's the lifters that go first, then take out the lobe. In fact, the tech at Comp Cams told me that once the cam is broke in, the nitrided surface breaks down and eventually matches the hardness of the lifter. Right.... Clay Smith, Isky, Crane, and several others, experimented with nitriding several years ago. They found that nitriding offered no advantage, simply because they couldn't offer a lifter with the same hardness, at an affordable price. Yes, lifters can be made to match the hardness, but at a considerably higher price (which is probably why Comp Cams doesn't offer them). Next they discovered that a cam, or crankshaft, that had been nitrated was more prone to cracking due to stress resulting from flex and temperature fluctuations. Once the surface is damaged in any way, it cracks and eventually disintegrates, which accelerates wear at an even faster pace. And as expected, the mismatched cam and lifter hardness accelerates wear on the weaker component (lifters), which is true on all metal parts where the hardness is mismatched, such as distributor gears. On a final note, the nitrided cam carries the same warranty as a non-treated cam. If the process is as good as they say, why don’t they offer an extended warranty on the treated cams? | ||
| + | |||
| + | Cam manufacturers found the better solution was to produce cams cores with a higher nickel content, which raised the hardness to 42-46 on the Rockwell scale. By using lifters that match the hardness of the cam, which are affordable to produce, wear is greatly diminished. Today there are literally millions of consumers using high nickel cams, of which a very small percentage have had wear issues that are directly related to cam hardness. Cam failures, or lobe wear, can almost always be traced back to improper break-in, the use of cheaper motor oils, or the use of high volume oil pumps. As such cam manufacturers don't offer nitriding, simply because it isn't needed, especially if you use a good quality oil and follow the recommended break-in procedures, including a high quality break-in oil. On the other hand, if you insist on using a high volume oil pump and/or high pressure valve springs for boosted applications, then a treated cam might be better suited. Just be prepared to change out the lifters on a regular basis, which means pulling the cylinder head frequently, or spending several hundreds of dollars on chilled lifters. | ||
| + | |||
| + | Comp Cams is a huge corporation with thousands of employees, which finds itself in the same position that Crane Cams was in not long ago. Considering many of the engines produced today don't benefit from cam swaps, and the dwindling economy, the demand for aftermarket cams is steadily dropping. So how does a large corporation suffering from a lack of sales, up the ante to get you to shell out those hard-earned dollar bills? Easy, they dream up a new product and convince the average uninformed consumer that it’s something they can’t live without. Sound familiar? Personally I can find better uses for my money. | ||
| + | |||
| + | As for stock springs, (let's talk about inline motors for a minute), I’ll post a few facts and let you guys make your own decision. Personally, I think they are perfectly suited for the applications they are recommended for. Not only do they work well, they are less than half the price of aftermarket springs, and they are readily available from any local parts store. | ||
| + | |||
| + | AK Miller (hot-rodder, racer, engine builder, and the Godfather of inlines) used stock SBF springs on every motor he built with excellent results, and commented that they were adequate for motors up to 6000 rpm with a .060 shim. He even used them successfully on his turbocharged motors, as did Bill Strobe (racer and engine builder). Mr. Miller was also a Performance Advisor for Ford Motor Company and Ford Racing, and was considered by many to be the worlds leading authority on inline sixes. Miller and Strobe joined forces on several projects and wrote numerous tech articles for Ford Motor Company and various magazines. In the 60’s he authored an article entitled “Horsing Around with the Mustang Six - Parts 1&2” for Hot Rod Magazine. In that article, he used stock 289 springs with a 260 duration cam, which raised the rpm capabilities of the Falcon six from 4500 rpm to 5500 rpm. Not bad for a piece of junk. | ||
| + | |||
| + | The Schjeldahl Brothers, authors of the Falcon Six Cylinder Performance Handbook, have used SBF springs in their motors successfully, and recommend them in their handbook as an alternative to stock springs. | ||
| + | |||
| + | Jack Clifford, founder of Clifford Performance and one of the most respected pioneer’s in inline performance, stated that spring pressures should not exceed 100# closed for inline sixes. Ed Iskenderian, founder of Isky Cams and the manufacturer for a majority of the camshafts sold by Clifford Performance, supported those recommendations as well. | ||
| + | |||
| + | Next we get to Comp Cams, which only stocks two different profiles for the small inline six. While they will custom grind any cam profile you want, so will any other cam manufacturer, and usually for less money. A few years ago, before Classic Inlines came about, the most popular cam was Comp Cams H260. The spring they recommend for that cam, part number 902-12, is rated at 48# closed, and 146# open. This is actually weaker than our stock springs, which are rated at 54# closed and 150# open. | ||
| + | |||
| + | Stock 289 springs are rated at 60# closed and 175# open, while this is only marginally better than the stock springs, I would use them over the Comp Cams springs or stock springs if I was given a choice. Next we have the stock 302 springs, which are rated at 80# closed and 200# open. Stock 302 springs are considerable stronger (40% closed, and 27% opened) and are perfectly suited for mild performance cams within a given rpm range. | ||
| + | |||
| + | The suggested applications posted on the Classic Inlines website, were recommended by George "Honker" Striegel, who is the owner of Clay Smith Cams, multi record holder in drag racing, and another pioneer in inline performance. While George is renowned for his V8 race engines, he is no stranger to our inline sixes. Back in the sixties and seventies, AK Miller, Bill Strobe, and George built and raced a drag boat powered by a Falcon Six, setting numerous records. While racing boats, George won numerous world championships, and was the first driver to acquire the APBA Triple Crown with his competition jet-boat (the American Revolution). | ||
| + | |||
| + | Ask anyone in the business (manufacturing or professional racing), that has personally met George, and you'll get one common answer. He is perhaps one of the most knowledgeable persons in the business, and is certainly one of the most respected. | ||
| + | |||
| + | Clay Smith grinds all of the camshafts sold by XXX. We currently stock seventeen different profiles (about 150 cams), on the shelf, ready to ship. However Clay Smith Cams has more than a 1000 masters on hand, which gives them the capability to make up just about any cam profile you can dream up. | ||
| + | |||
| + | I could go on, but I think I’ve made my point. All of the above professionals, all experts in inline performance, have used and/or recommend the use of stock springs. Therefore, if I’m an idiot, at least I’m in good company.'' | ||
| + | |||
| + | __________________ | ||
===Racer Brown's position on oil level during break-in=== | ===Racer Brown's position on oil level during break-in=== | ||
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''"Overfill the crankcase by at least 4 or 5 quarts of oil so that the oil level comes to within an inch of the top of the oil pan. Install a set of fairly hot spark plugs with a gap of 0.050" to 0.060" to prevent oil-fouling of the plugs, which is otherwise inevitable under no-load conditions with all the extra oil aboard. During this operation, we want near-maximum oil flow, together with a maximum of oil vapors and liquid oil thrashing about in the crankcase so that the cam lobe and lifter interface lubrication is considerably better than marginal."'' | ''"Overfill the crankcase by at least 4 or 5 quarts of oil so that the oil level comes to within an inch of the top of the oil pan. Install a set of fairly hot spark plugs with a gap of 0.050" to 0.060" to prevent oil-fouling of the plugs, which is otherwise inevitable under no-load conditions with all the extra oil aboard. During this operation, we want near-maximum oil flow, together with a maximum of oil vapors and liquid oil thrashing about in the crankcase so that the cam lobe and lifter interface lubrication is considerably better than marginal."'' | ||
</blockquote> | </blockquote> | ||
| + | |||
| + | ===Lubrication requirements after break in=== | ||
| + | For the same reasons break in oil or break in oil additives are used to break in the cam and lifters, '''''after''''' cam/lifter break in, only oils formulated for flat tappet equipped performance engines should be used. Also acceptable is using additives like ZDDPlus, etc. (in the correct quantity- less than for initial break in) added to over the counter motor oil. | ||
===Lubricants=== | ===Lubricants=== | ||
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*[http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=159&Category_Code= Comp Cams Engine Break-In Oil Additive] | *[http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=159&Category_Code= Comp Cams Engine Break-In Oil Additive] | ||
*[http://www.hotrodders.com/forum/assembley-lube-good-anything-174183.html#post1239633 Hotrodders forum thread on cam and assembly lubricants] | *[http://www.hotrodders.com/forum/assembley-lube-good-anything-174183.html#post1239633 Hotrodders forum thread on cam and assembly lubricants] | ||
| + | *[http://www.enginebuildermag.com/Article/106244/breakinin_is_hard_to_do.aspx How break-in oils are different than the rest and why you need them] Engine Builders Magazine | ||
| − | == | + | ==Adjusting the cam timing or "phasing"== |
| − | + | Cam phasing is the relationship of the camshaft position to the crankshaft position in reference to TDC. A change of 2 degrees at the cam gear equals 4 degrees at the crank. | |
| − | + | ||
| − | + | {{Note1}}When advancing/retarding the cam, be sure to check valve to piston clearance. Each degree of change effects valve clearance approximately 0.010". Example: If you advance the camshaft 4 degrees, you will '''lose''' about 0.040" clearance between the intake valve and piston, and you will ''gain'' about 0.040" clearance between the exhaust valve and piston. It will be the opposite if the camshaft is retarded. | |
| − | + | ||
| − | + | The cam timing, or phasing, can be changed at the time of installation by using a multi-keyway timing set, or an adjustable cam gear like [http://www.cloyes.com/HighPerformance/Products/HexAJustTrueRollerSets/tabid/383/language/en-US/Default.aspx Cloyes Hex-A-Just]. | |
| − | + | ||
| − | + | On timing sets that have no built-in adjustability, the cam phasing can still be adjusted in many cases. This is done by drilling the dowel pin hole of the cam gear oversize in order to use a bushing to advance or retard the cam gear. On engines where this isn't practical, an offset crank gear Woodruff key can often be used instead. | |
| + | {| | ||
| + | |[[File:Cam bushings.jpg|thumb|center|280px|Cam gear bushing selection]] | ||
| + | |[[File:Offset crank keys.jpg|thumb|center|250px|Crank gear offset key selection]] | ||
| + | |} | ||
| + | In the majority of cases, installing the cam "straight up" (without any advance/retard added by the installer) is the correct way to install the cam and timing set. Many cam makers have already advanced (in most cases) the cam timing when the cam was made to suit the application. Unless the builder has access to an engine dynamometer or has advanced knowledge of the dynamics involved, advancing/retarding a cam is nothing but a shot in the dark as to whether it will result in any benefits at all. And there's the chance the engine output could be adversely affected by indiscriminately changing the phasing of the cam. The piston to valve clearance can be reduced enough to cause damage in some cases. | ||
| + | |||
| + | ==Effects of changing cam timing== | ||
| + | |||
| + | ===Advance timing=== | ||
| + | *Open Intake Valve Sooner | ||
| + | *Builds more low-end torque | ||
| + | *Decreases piston to intake valve clearance | ||
| + | *Increases piston to exhaust valve clearance | ||
| + | |||
| + | ===Retard timing=== | ||
| + | *Keeps intake valve open later | ||
| + | *Builds more upper RPM power | ||
| + | *Increases piston to intake valve clearance | ||
| + | *Decreases piston to exhaust valve clearance | ||
| + | ;Also see [http://www.crankshaftcoalition.com/wiki/How_to_choose_a_camshaft#Phasing_the_camshaft Phasing the camshaft] | ||
| + | |||
| + | ==Effects of changing lobe separation angle== | ||
| + | The lobe separation angle (LSA) is ground into the cam at the time of manufacture and cannot be changed by the installer. | ||
| + | |||
| + | ===Widen (larger) LSA=== | ||
| + | *Raises torque to higher RPM | ||
| + | *Reduces maximum torque | ||
| + | *Broadens power band | ||
| + | *Reduces maximum cylinder pressure | ||
| + | *Decrease chance of engine knock | ||
| + | *Decrease cranking compression | ||
| + | *Decrease effective compression | ||
| + | *Idle vacuum is increased | ||
| + | *Idle Quality improves | ||
| + | *Overlap decreases | ||
| + | *Natural EGR effect is reduced | ||
| + | *Increases piston-to-valve clearance | ||
| + | |||
| + | ===Tighten (smaller) LSA=== | ||
| + | *Moves torque to lower RPM | ||
| + | *Increases maximum torque | ||
| + | *Narrow power band | ||
| + | *Builds higher cylinder pressure | ||
| + | *Increase chance of engine knock | ||
| + | *Increase cranking compression | ||
| + | *Increase effective compression | ||
| + | *Idle vacuum is reduced | ||
| + | *Idle quality suffers | ||
| + | *Overlap increases | ||
| + | *Natural EGR effect increases | ||
| + | *Decreases piston-to-valve clearance | ||
==Roller cams are '''not''' immune== | ==Roller cams are '''not''' immune== | ||
While the move has been made by the OEMs to stop using flat tappet cams and lifters in production vehicle engines (replaced by hydraulic roller cams and lifters), they are not immune to failure. | While the move has been made by the OEMs to stop using flat tappet cams and lifters in production vehicle engines (replaced by hydraulic roller cams and lifters), they are not immune to failure. | ||
| − | The same type of oil additives should be used, because it is not just the cam and lifters that require a high pressure lubricant additive; | + | The same type of oil additives should be used, because it is not just the cam and lifters that require a high pressure lubricant additive; use the heavy moly cam break in lube on a roller cam or lifter- it will cure problems. If those are not available for some unknown reason (all should be found online), use motor oil or a roller lifter-specific lube for the roller lifters and cam. |
{| | {| | ||
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*[http://www.carcraft.com/techarticles/ccrp_1108_camshaft_break_in_guide/viewall.html Camshaft Break-In Guide - How To Break In That Flat-Tappet Cam] Car Craft, August, 2011 | *[http://www.carcraft.com/techarticles/ccrp_1108_camshaft_break_in_guide/viewall.html Camshaft Break-In Guide - How To Break In That Flat-Tappet Cam] Car Craft, August, 2011 | ||
*[http://www.sirgalahad.org/tyler/misc/camdesign.txt Cam design] | *[http://www.sirgalahad.org/tyler/misc/camdesign.txt Cam design] | ||
| + | |||
;Crankshaft Coalition Wiki articles | ;Crankshaft Coalition Wiki articles | ||
| + | *[[How to choose a camshaft]] | ||
| + | *[[Cam and compression ratio compatibility]] | ||
| + | *[[Lifters]] | ||
*[[Adjusting hydraulic lifters]] | *[[Adjusting hydraulic lifters]] | ||
| + | *[[Adjusting solid lifters]] | ||
*[[How to prep and start a rebuilt engine]] | *[[How to prep and start a rebuilt engine]] | ||
*[[Valve train points to check]] | *[[Valve train points to check]] | ||
| + | *[[Valve train geometry]] | ||
| + | *[[Pushrod length checking tool, homemade]] | ||
| + | *[[Valve spring tech]] | ||
*[http://www.crankshaftcoalition.com/wiki/Category:Adjust_valves Adjust valves] | *[http://www.crankshaftcoalition.com/wiki/Category:Adjust_valves Adjust valves] | ||
| + | *[[Camshaft tech by Dimitri Elgin]] | ||
| + | |||
;Hotrodders forum threads | ;Hotrodders forum threads | ||
*[http://www.hotrodders.com/forum/difference-measured-vs-calculated-coil-bind-clearance-192254.html?highlight=between+single+coil Valve spring coil bind] | *[http://www.hotrodders.com/forum/difference-measured-vs-calculated-coil-bind-clearance-192254.html?highlight=between+single+coil Valve spring coil bind] | ||
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