Valvespring Retainer Material

[MichaelPGriffith]

I'm trying to use valvesprings in my application (Honda V6, J32a2) that were designed for a different vehicle. The spring dimensions are workable and the seat pressure and open pressure are just what I'm looking for.

The caveats are; 1. Installed spring height needs to altered with shimmed seat locator. 2. No spring retainer & locks are shelved (that I've found) that have an acceptable interferance fit to the spring and still fits the Honda 5.5mm valve stem.

Solution for 1 is to have seat locators machined in 6061, hard anodizes, and then a hardened steel washer between seat locator and spring.

Solution for 2 is to have retainers machined from scratch.

Which brings me to my question; is hard anodized 6061 suitable for an application utilizing 85lb Seat and 195lb Open pressure?

 

[Tmoose]

I think aluminum retainers are generally considered to have limited life. I used some on the street in the 70s and they were always eaten up to some extent in the spring seat area, and the retainer/keeper area would "look" funny too.

In the current ISKY catalog only steel and titanium retainers are offered.

http://iskycams.com/pdf/2010Catalog-Full-Catalog.pdf

Lunati also

http://www.lunatipower.com/Category.aspx?id=26&pid=2

Comp cams too

http://www.compcams.com/Products/CC-'Valve Spring Accessories'-0.aspx

Dan T

 

[patprimmer]

Chrome molly retainers are used successfully in some very serious race engines.

Titanium helps to attain a few extra rpm at quite a high cost and reduced life.

Aluminium retainers where proven unsatisfactory in the 70s and I don't know one qualified or experienced person who would consider them for a minute.

Regards
Pat
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[Lou Scannon]

Pat, in applications where they're used, are titanium valve spring retainer failures (or pre-emptive retirement) a concern compared to cro-moly retainers in the same applications?

I forgot what I was going to say

 

[patprimmer]

The springs tend to wear a grove in them. I never ran one until it failed as noticeable wear was enough to scare me into replacing them.

They still seem to have quite a long life, but CrMo seems to have infinite life.

I never saw any real wear in them on a serious race engine as they get very regular inspection and everything else also time expires.

I have seen them worn on a street engine that had who knows how may miles on it. I replaced them with CrMo ones as that was all that was required.

The engines where all SBC with roller cams. The street engine had about 0.570"lift and 250# on the seat and up to 7000rpm. The race engines typically had 0.680 to 0.710" lift and 400# on the seat and up to 9000rpm

Regards
Pat
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[Lou Scannon]

Hmm, titanium retainers definitely seem like overkill on a street app. Good call on replacing them with Cro-Mo.

I forgot what I was going to say

 

[evelrod]

I used titanium in the 80's race engines. Never had a failure or even excessive worry marks from the springs. New engines I have built since the 2004 engine have used steel. Actually, the newer engines rev about 500 rpm higher than I did in the 80's. Different cams, to be sure.

I watched a Jay Leno bit the other day. The engine for his Lotus 26R being somewhat out of my reach ($$$$$$$$$$$) but quite impressive with all the alloy block and titanium valve gear.
Quite impressive as a 2 litre twincam. I think the only thing Lotus was the cam cover!!!!! So, bottom line, the titanium bits are great....IF you can afford them...as such, you can certainly implement a "zero defects" program. "What, me worry"?

Rod

 

[MichaelPGriffith]

Thank you all for your feedback. Speaking with one of the tech guys at Ferrea racing, and hearing him dismiss the aluminum retainers that his own company sells, I had a hunch that he might be right about them but wanted to bounce the question off of you guys.

The valve spring and valves for testing the retrofit arrived today. And, as luck would have it, the OEM retainer (which I assume is chromoly) and seat locator are both a nice snug interference fit into the new spring. So, the only concern now is shimming the seat locator a few mm. Almost feels like this is just too easy.

I suppose I shouldn't get my hopes up just yet; I still haven't determined whether the spring rates on this new spring are suitable for my application.

My cam regrinder came back to me with the lobe lift numbers for the OEM cam and I plugged them into a basic CAD program in order to tinker with the base circle size ect... I didn't feel as though the regrinder was able to offer the sort of design freedom I am looking for so I decided to have master tooling CNC'd for a J series regrind.

At this point I've only gone into the CAD model and measured the lobe lift in individual degrees for -10 to 45* ATDC. (The cam data from the regrinder was presented in duration per given lift and lca's) I charted the cam angle by individual degrees manually within the model (creating a line, specifying the correct angle, snapping to center, intersecting, deleting lines outside the diameter of the lobe, and then checking the length of each line compared to the base circle) and also did the same for a prospective regrind profile. I then mapped piston position by crank angle and compared the triangulated valve intrusion into the chamber against it; making sure there wouldn't be problems there.

I still need to go through the rest of the angles on the model to map the lift curve. Exactely where I'm going from there to measure velocity and acceleration of the valves isn't very clear to me (any direction here would be appreciated) but I understand that I should be able to make an informed decision from that point.

The OEM valvetrain has been tested with aftermarket springs (two companies offer them) on a Spintron and shown capable of remaining stable at 10krpm. This is with OE cams though, and the valve springs are actually fairly mild; 70lbs of seat pressure and 150lbs @~10.25mm of lift. My prospective regrind profile will give 12.4mm of lift and 268* of intake duration on the Vtec lobe as opposed to ~240*.

Anyway, I hope you gentlemen don't mind my thinking out loud; I had a thread on here a while back properly titled "elementary Q&A" but it's been closed presumably due to lack of use. Any feedback is greatly appreciated.

 

[MichaelPGriffith]

Here's a more direct question; How do you feel about the possibility of replacing a OEM 36mm IN valve with a 35mm Ferrea Comp Plus IN valve considering the following:
1. The OE valve is 54g compared to the 35mm's 50g.
2. Honda replaced the 36mm IN valve with a 35mm valve of nearly identical dimensions (to the Ferrea valve) in the newer J-series engines.
3. The 35mm valve has a smaller pocket in the face and will thus raise compression slightly.
4. The valve seats in the 36mm OE and 35mm OE engines are the same; they are the same diameter at the transition point from throat to seat.
5. The curtain area, in my application, is going to increase significantly in spite of the decreased valve diameter because my valve lift will be increasing 2.3mm.

 

[evelrod]

I don't see a problem with the smaller valve. We had a similar problem with our ex TRD 2TC that by going to a smaller valve improved flow significantly. I don't recall taking the wt into consideration. One note about valve springs...In my far distant past it was common to put super heavy springs on just about everything. Years of experience now dictate the softest spring that will still leave a safety margin in the event of an overrev. All our ign systems have rev limiters, though. Can't say much about your lift/timing numbers without knowing what lift they are measured at and the basic acceleration curve. My vintage Mini uses 36.6mm/31mm valves with 98/245 springs @ 0.486" lift... and I rev to 8500 on occasion and 8000 quite often without problem...and that engine is a dinosaur!

Rod

 

[MichaelPGriffith]

I'm working on plotting the lift curve for the regrind profile right now. When I get that figured I can talk details of the acceleration curve.

I looked through the forum trying to find some good info on stem/guide clearance and found a few old locked posts. Someone mentioned running them so tight that they had to be hammered apart. What is the tightest clearance you would consider running between the guide and stem; materials being hard chrome plated stems and manganese bronze guides? The stems are a meager 5.5mm, won't see any FI type temps on the exhaust side, and the valves and chamber face will be ceramic coated.

 

[evelrod]

Michael, I realize your shooting for 'state of the art' with this but, as I see it, there is a point of 'diminishing return' in all this. Stem/guide clearance is published for just about every engine. I'm a dinosaur and my clearance is probably way to much for your consideration. Lots of things go into that particular dimension, not just temp. Lubrication, speed/acceleration, method of actuation, etc. I cannot afford even the possibility of a 'stuck valve' so my settings are on the loose side with valve seals to avoid any oil control issues. All newer engines have cut down on clearance in just about every part for NVH or whatever. My years of racing experience is not sufficient for me to comment on these issues. I've never built an engine that I expected to last 200,000 miles!!!

Rod