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-   -   Making solid lifters for my FE3N (https://www.miataturbo.net/engine-performance-56/making-solid-lifters-my-fe3n-107331/)

fastivab6tg25mr Sep 13, 2022 06:10 PM

Making solid lifters for my FE3N
 
8 Attachment(s)
Cross posting from my build thread cause I am looking for input. Long story short I bought a FE3N head from South Africa and the custom cams were the only non crap part of the whole package. The cam is supposed to have solid lifters and the "solid lifters" that were provided with the head look like hacksawed bolts rammed into the HLA holes in the buckets with a groove to bleed off oil pressure.

My initial plan was to use M52 supertech 33mm buckets but the longest stem they have is 14mm with lash shims that go to 4mm max. I have approx 19.7mm to base circle from the tip of the valve.
It has been suggested to me to have 3mm(ish) welded to the tips of the valves and then grind them back for proper clearance. I never heard of welding onto valves and would question how long they would hold clearance cause they wouldn't be hardened like the stock valves would be.

The plan I came up with is to hollow out the HLAs and install 10mm lash adjusters from a VROD/Buell1125R inside the HLA to make it solid. I would also be removing some material from the under side of the bucket to reduce weight and gain access to the inside of the oiling hole to pin it shut with some 1/16" brass rod.
Doing this gives me the availability to use off the shelf parts that are readily available. With my one test lifter I made so far I would save 15% in lifter weight vs a stock HLA that's full of oil.

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curly Sep 13, 2022 10:42 PM

Make 16 sleeves and use BP solid lifters.

Have you seen this thread? https://www.mx6.com/threads/how-i-bu...or-fe3.215963/

fastivab6tg25mr Sep 13, 2022 11:40 PM

What I'm doing is practically the same but using interchangeable shims so I don't need to machine each insert perfectly. I can just measure the valve clearance and swap in the appropriate shim.

TurboTim Sep 14, 2022 10:19 AM


Originally Posted by fastivab6tg25mr (Post 1627873)
Cross posting from my build thread cause I am looking for input.

What input would you like?

fastivab6tg25mr Sep 14, 2022 11:30 AM

Links to someone already trying it before, weather it failed or worked. The FE3N HLA insert is identical to the BP05. the down side is the bucket on the FE3N is 9mm bigger. Seeing if there is another way to make it happen.

When I come up with a solution to a problem and I cant find anyone else that has solved it the way I'm thinking of I do not assume I'm a genius, I assume it's a bad idea and I'm not seeing why it won't work.

TurboTim Sep 14, 2022 01:27 PM

Nah your idea is sound. Just find the most affordable shim kit. I see 10mm shim kits around $80 on ebay in .072-.128 thickness every .002, then mcmaster 3/8"OD shim kits for $13 in .001" sizes to fine tune if you run out of correct shim sizes in your ebay kit. You can individually order the shims from mcmaster. Well in packs of 10 anyway, but for around ~$5-13.

fastivab6tg25mr Sep 16, 2022 02:46 PM

I have this posted in a few different groups. seems people are most concerned with the brass plug backing out and damaging the cylinder head. do you think id be better off zapping the hole closed with a mig welder instead of the brass pin?

LeoNA Sep 16, 2022 05:55 PM

It seems like a difficult and risky solution. Why not just use the ST shim under bucket lifter with lash caps on the lifter and valve. Could always make the lifter shim a light press fit and use the valve shim for adjusting the clearance. I believe that ST also offers 1-2mm longer stem valves for small base circle cams.

fastivab6tg25mr Sep 22, 2022 10:47 AM

Would it not be riskier to stack lash caps and shims vs plugging an oil hole? I've been going through the Supertech and Ferrea catalogs until my eyes bled and the longest extended stems I saw were the .6mm longer ones fab9 sells.

TurboTim Sep 22, 2022 11:07 AM


Originally Posted by fastivab6tg25mr (Post 1628018)
I have this posted in a few different groups. seems people are most concerned with the brass plug backing out and damaging the cylinder head. do you think id be better off zapping the hole closed with a mig welder instead of the brass pin?

Welding would warp the piece.

Drill/tap and add a set screw with loctite. We use 2-56 set screws & loctite to plug oil holes in some of our lifters.

A tight brass plug shouldn't come out; it has a higher thermal expansion coefficient than steel.

LeoNA Sep 22, 2022 08:26 PM

You would have to make or have a set made that will get you in the ball park to be able to use the off the shelf units for adjusting.



Originally Posted by fastivab6tg25mr (Post 1628329)
Would it not be riskier to stack lash caps and shims vs plugging an oil hole? I've been going through the Supertech and Ferrea catalogs until my eyes bled and the longest extended stems I saw were the .6mm longer ones fab9 sells.


technicalninja Sep 22, 2022 08:59 PM


Originally Posted by fastivab6tg25mr (Post 1628329)
I've been going through the Supertech and Ferrea catalogs until my eyes bled and the longest extended stems I saw were the .6mm longer ones fab9 sells.

I would not count on the Supertech valves being .6mm longer anymore.
I needed the .6mm longer valves for a bp6d head I did for a forum member this spring (SUB install). Had SuperMiata overnight a brand-new set. They were stock length.
My customer was incised. He called Supertech and found out that they had too many problems with the extended length valves (installer issues, not valve issues) that they changed to standard length valves 2-3 years back.
Didn't tell anyone, everyone still lists the valves as .6mm longer than stock.

Just last week I purchased a bunch of engine parts from a member that never finished his build. Most of the dates on the boxes were 2012. Included was a set of Supertech SS intakes and Inconel exhaust.
First thing I did was measure them. They are actually 1.0 mm longer than stock.
So Supertech's current info is off, and the actual oversize of the longer valves was longer than they said.

This might not have anything to do with the parts available for a FE engine.
I just no longer trust any "specs" that Supertech publishes...

fastivab6tg25mr Sep 28, 2022 09:58 PM


Originally Posted by technicalninja (Post 1628374)
This might not have anything to do with the parts available for a FE engine.
I just no longer trust any "specs" that Supertech publishes...

The problem is that I have yet to find anything that's specifically for the FE3N. It's all measurements and see what's available for other cars. Which brings me to valve springs. I measured an installed height of 33mm(ish) BP05s look like they have between a 34mm-35mm depending on source. Again looking at supertech catalog for single springs and I'm seeing the BP, RB20, Honda B18A/B, B20, RB25, VG35DET, 1JZ,2JZ, MZR 2.0,2.3,2.5, and Turbo, duratec 2.3,2.5 all have the same valve springs with an installed height between 33-35mm. Which are close enough in specs to fit the FE3N. According to my measurements The valves and springs are within the total range of the cam's 10.7mm lift. The valves are 1.4mm shorter but the Miata single springs are good for 12.9mm max lift. I have already ordered the +1 valves from fab9. I'll check all measurements when they arrive before ordering springs.


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