Need help from the flathead gurus...? Valve clearance issue

[rotorwrench]

The Tobin ARP or Sunnen TR-6700 tappet refacing machines do use a relatively straight face grinding wheel but it only contacts between the center and the outside edge of the follower since the follower is set on a slight angle to the wheel and basically centered between the center point and outside diameter. The cam follower or tappet is spun in this position and the feed pushes the tappet into the grinder wheel along with a coolant flow. A quick skim pass off the surface will sometimes show up the wear areas on the face until it is completely refinished. I think there is a U-tube video of a machinist operating one of these bad boys.

[crazycasey]

Originally Posted by Bored&Stroked

The lifters should have a slight convex shape to the bottoms of them - they should not be surfaced to a flat state. It sounds like he has a set of used lifters - which could explain the large differences in length.

Lapping: This procedure can't be used to tighten up your clearances - it is only to fine tune the sealing surfaces, not anything more.

As many noted: I'd be suspect of the whole valve train setup:

a) Spring heights need to be correctly setup - such that you have the correct amount of pressure on the valve seats. Using Chevy valves makes this a bit more difficult - but there are plenty of ways to deal with it - depending on the combination of lifter types/lengths, shims, retainers, lash-caps, keepers, etc..

b) The lifters should be newly resurfaced - or new. Unless the bottoms of the lifters are practically new (and convex) - you probably do not want to reuse them "as is". I would not - it is not worth saving a few bucks in this area.

c) Machine Shop: The comment about "not being hard enough" would worry me. Seems like a way to sell you more parts and/or work - has nothing to do with Chevy valves. Truth be told, the stem ends have a lot more pressure and wear tendencies with a rocker arm, than a direct tappet on a flathead.

If it was me - I'd find a much better machine shop and ensure that everything gets done by experienced flathead folks.

Punting: If you have the capabilities and equipment to measure and set spring heights, you may be able to use the same valves, same guides and change the lifters to adjustables . . . but that is a big assumption on my part. It is really important to know what your current spring heights/pressures are - before thinking of that approach.

Best of luck . . .

B&S

Dale,

Your post from the other site (it's a GOOD ONE):

http://www.jalopyjournal.com/forum/t...inions.420484/

I think THAT's my answer, with the turned down Comp Retainers and a new set of oem non-adjustable lifters to bring my clearances back in spec. Either that, or the Comp adjustable tappets, as they seem to be short enough to use Chevy valves without removing a TON of material. I just have no clue as to their quality, and whether or not they're heavy enough to warrant more valvespring.

Where's the best place to buy a set of Zephyr springs? Red's!?

[flatheadmurre]

Start by asking yourself how much springpressure do you really need...are you going to rev it hard...is it a really that wild cam with fast lift...no more then you absolutely need is best.
With a harder/longer spring you might end up with just enough pressure on the seat as is...think it over and measure some before you go shopping for more parts.

[JSeery]

Is there a problem with your current springs? The lifter you use is not a big factor in the spring selection. It will be a little bit difficult to use adjustable lifters with your reground cam without some block modifications. It can be done, but a little hard to adjust. I think your NOS lifters is the best selection.

Spring pressure is established at a spring height and thus the shims. With Chevy valves the keeper grooves are futher from the head and require a lot more shiming.

[crazycasey]

Originally Posted by JSeery

Is there a problem with your current springs? The lifter you use is not a big factor in the spring selection. It will be a little bit difficult to use adjustable lifters with your reground cam without some block modifications. It can be done, but a little hard to adjust. I think your NOS lifters is the best selection.

Spring pressure is established at a spring height and thus the shims. With Chevy valves the keeper grooves are futher from the head and require a lot more shiming.

I follow all of that, and I've seen on other posts where you can shim your way out of the spring register pretty quickly with the Chevy valve, often before the correct spring preload is achieved on something like a Zephyr spring.

Isky didn't give me a spring spec, they just tried to sell me a spring. I emailed Ron to see if he can give me some better information, but haven't heard back.

My stock springs are meant to be installed at a 2.130" seat height. I should actually be really close to this with the Chevy valve, but I haven't measured yet, and that's only going to give me between 40-45 lbs on the seat...not likely enough for the Isky 88 cam and ANY kind of rpm.

Anybody care to weigh in on my thought process here!?

[GOSFAST]

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Originally Posted by crazycasey

Yep, that's beautiful! Are those the Comp adjustable tappets? And are those a "Zephyr" spring or a stock spring? After doing a little more research, it appears I have stock springs in this motor, so those will need to be changed as well. If you had the spring locators ready to ship I'd probably just give you my credit card number and start fresh at this point. I really thought I was FINALLY on the home stretch with this thing.

It seems like the basic answer is that you can't build a flathead with Chevy valves, unless you have the ability to make/modify the spring seat or retainer.

Hi Casey, one more time, that setup in the photos doesn't use the locators we're waiting on, the guides would be slightly different for the locator setup.

We are a Comp dealer but we buy the Flathead lifters direct from Topline, Comp Cams also buys theirs (811-FH's) from them so I know you'd be getting the correct parts for sure!

(Add) Have never needed a "Zephyr" spring in my life, and back in the mid '80's were doing 15 Flatheads per year. We were involved heavily with a build for a Flathead powered stock-car from upstate N.Y. Owner is very good friend to this day, sold the ride a while back. Saw 5000 RPM+ every weekend going in circles??

Thanks, Gary in N.Y.

P.S. It's really a headache when things don't go as planned, hang in there! Don't be "afraid" to come up here and ask questions still, like I said earlier, it'll all come around eventually.

[crazycasey]

Originally Posted by GOSFAST

Hi Casey, one more time, that setup in the photos doesn't use the locators we're waiting on, the guides would be slightly different for the locator setup.

We are a Comp dealer but we buy the Flathead lifters direct from Topline, Comp Cams also buys theirs (811-FH's) from them so I know you'd be getting the correct parts for sure!

(Add) Have never needed a "Zephyr" spring in my life, and back in the mid '80's were doing 15 Flatheads per year. We were involved heavily with a build for a Flathead powered stock-car from upstate N.Y. Owner is very good friend to this day, sold the ride a while back. Saw 5000 RPM+ every weekend going in circles??

Thanks, Gary in N.Y.

P.S. It's really a headache when things don't go as planned, hang in there! Don't be "afraid" to come up here and ask questions still, like I said earlier, it'll all come around eventually.

Gary,

I really appreciate all the info. Hey, so is that a stock spring!? And do you install it at the recommended 2.130" height, resulting in...40-ish lbs on the seat? I'm going to take my springs in and have them bench tested, and then take some measurements with a test spring in my block.

[JSeery]

Think around 55 lbs seat pressure is a common recommendation.

Corrected psi LOL

[40cpe]

I used chevy valves and adjustable lifters on a reground camshaft. I also used Zephyr springs. I don't remember what my final installed height was, but I was able to get 48-55 lbs using one .060 shim on all of them and a .010 on a few. The ones that have .010 shims are on the retainer end because of no more register on the guide. I know that ideally one shouldn't install the shims on the moving end, but the .010 shim is really light. Certainly no more that a lash cap is how I justified it to myself.

Jim at Red's Headers told me the Zephyr spring would produce about 80# on a stock ford valve. I didn't want that much, hence the longer valve and use of shims.

[crazycasey]

Originally Posted by 40cpe

I used chevy valves and adjustable lifters on a reground camshaft. I also used Zephyr springs. I don't remember what my final installed height was, but I was able to get 48-55 lbs using one .060 shim on all of them and a .010 on a few. The ones that have .010 shims are on the retainer end because of no more register on the guide. I know that ideally one shouldn't install the shims on the moving end, but the .010 shim is really light. Certainly no more that a lash cap is how I justified it to myself.

Jim at Red's Headers told me the Zephyr spring would produce about 80# on a stock ford valve. I didn't want that much, hence the longer valve and use of shims.

Interesting approach. Did you drill a hole in the lifter boss to adjust your lifters? This approach might be a good work around for my situation.

[crazycasey]

Originally Posted by JSeery

Think around 55 lbs seat pressure is a common recommendation.

Corrected psi LOL

So, rather than install the stock spring at the suggested 2.130" seat, I would run it on a Spring tester, see where in it's travel it made 55psi, and then install the springs AT that height!?

[40cpe]

Originally Posted by crazycasey

Interesting approach. Did you drill a hole in the lifter boss to adjust your lifters? This approach might be a good work around for my situation.

Yes, I did.

Originally Posted by crazycasey

So, rather than install the stock spring at the suggested 2.130" seat, I would run it on a Spring tester, see where in it's travel it made 55psi, and then install the springs AT that height!?

Correct. I think you would want to test each spring and label it with the correct height. Mine varied a bit. Installed height varied a bit, so with matching springs with installed height, shim them to your final pressure.

[crazycasey]

Originally Posted by 40cpe

I used chevy valves and adjustable lifters on a reground camshaft. I also used Zephyr springs. I don't remember what my final installed height was, but I was able to get 48-55 lbs using one .060 shim on all of them and a .010 on a few. The ones that have .010 shims are on the retainer end because of no more register on the guide. I know that ideally one shouldn't install the shims on the moving end, but the .010 shim is really light. Certainly no more that a lash cap is how I justified it to myself.

Jim at Red's Headers told me the Zephyr spring would produce about 80# on a stock ford valve. I didn't want that much, hence the longer valve and use of shims.

Were the tappets from Red's? Do you recall how much you had to take off the valve stem to get them to work? Is valve stem hardness a concern at that point?

[40cpe]

Yes, tappets from Red's. I didn't have to take any off the valve stems. My cam is a 3/4 grind on an original ford cam, so the lifters were lower in the bores than if I was using a stock cam. If your cam used a new blank your mileage may vary.

[flatheadmurre]

Ok a bit of metalurgy stainless steel doesn´t harden like carbonsteel, so there´s not hardened stems,tips or such if the valve is stainless.
Heat treatening stainless gives you different grainstructures but not hardening.
What you do to add wear strenght to a stainless valve stem is coating it with something.
Hard tips are welded or sprayed on.

[crazycasey]

Originally Posted by flatheadmurre

Ok a bit of metalurgy stainless steel doesn´t harden like carbonsteel, so there´s not hardened stems,tips or such if the valve is stainless.
Heat treatening stainless gives you different grainstructures but not hardening.
What you do to add wear strenght to a stainless valve stem is coating it with something.
Hard tips are welded or sprayed on.

I don't believe that my valves are stainless steel. How would I know for sure? Magnet I guess!?

[flatheadmurre]

Magnet is the way to go.
Valves are not always 1 piece either.
Can be 3 pieces welded togetter.

[crazycasey]

Originally Posted by flatheadmurre

Magnet is the way to go.
Valves are not always 1 piece either.
Can be 3 pieces welded togetter.

I'm pretty sure they're just a basic, cheap, cast valve because they're dull grey in color everywhere they're not machined. I'll magnet test them tonight, though I'm failing to understand why it matters.

[JSeery]

Originally Posted by crazycasey

though I'm failing to understand why it matters.

It doesn't, think these are responses to your question about loosing the hardness in the valve tip. In an OHV engine the rocker slides back and forth on the valve tip and even with a roller rocker there is some movement. A flathead has the valve directly above the lifter and a hardened surface is not as big a concern as an OHV engine.

[crazycasey]

Originally Posted by GOSFAST

Hi Casey, one more time, that setup in the photos doesn't use the locators we're waiting on, the guides would be slightly different for the locator setup.

We are a Comp dealer but we buy the Flathead lifters direct from Topline, Comp Cams also buys theirs (811-FH's) from them so I know you'd be getting the correct parts for sure!

(Add) Have never needed a "Zephyr" spring in my life, and back in the mid '80's were doing 15 Flatheads per year. We were involved heavily with a build for a Flathead powered stock-car from upstate N.Y. Owner is very good friend to this day, sold the ride a while back. Saw 5000 RPM+ every weekend going in circles??

Thanks, Gary in N.Y.

P.S. It's really a headache when things don't go as planned, hang in there! Don't be "afraid" to come up here and ask questions still, like I said earlier, it'll all come around eventually.

Gary,

Can you tell me, conveniently, what the overall height on those TopLine adjustable lifters is, at both ends of the adjustment? Curious how close they'll be with my Chevy valves and reduced base circle cam.

Thanks again for all your help!

Casey