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PostPosted: Mon Dec 09, 2019 6:55 am 
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Joined: Tue Sep 03, 2013 1:03 pm
Posts: 38
Location: Upstate SC near CLEMSON!
Working on a 1.6 FP Miata engine. Trying to get a lighter valve train setup. My old engine still has hydraulic lifters, and am trying to build a bit of a better engine to replace it.

Any tips on who has these besides Maruha (Japan) and MazdaSpeed? We have been using a surface grinder on the shim over bucket type, but do not know how to trim those tiny things that sit on top of the valve stem. Buying a boatload to get the right thickness at $14 each is a bit of a reach for me.

Interesting that Maruha has 20 thicknesses available and MazdaSpeed part number is B6N7-12-561 is the only one available from them and is of course just one thickness.

cheers

Henry Payne


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PostPosted: Mon Dec 09, 2019 8:14 am 
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Joined: Fri Dec 23, 2011 6:59 am
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Location: Spring Hill, FL.
Supertech should have the lifter and shims.
I grind all of mine on the stem grinder part of am old valve grinding machine .

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Mike Ogren/Protech Racing, http://www.FWDracingguide.com http://www.ogren-engineering.com/ 352.428-8983 mogren@tampabay.rr.com


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PostPosted: Tue Dec 10, 2019 6:59 am 
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Joined: Sun Dec 06, 2015 5:33 am
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Location: Titusville, Fl.
There are outside company's that sell valve bucket pucks or lash caps of different sizes & thicknesses. Buy the size & grind to fit. Quite a few cars use these now & in the past. Even push rod motors sometimes use lash caps.
6 cylinder Jaguars from the 50's & 60's used them. 8 hours flat rate to do a valve adjustment if you were good with math.

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Sam Seay
I might not always be right but i ain't NEVER wrong!


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PostPosted: Tue Dec 10, 2019 9:16 am 
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Joined: Thu Jan 22, 2004 3:31 pm
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Did the rules change. I thought limited prep meant stock only lifters?


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PostPosted: Tue Dec 10, 2019 9:30 am 
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Joined: Tue Oct 27, 2009 6:39 pm
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Nothing changed.

"Any lifters, tappets/cam followers of the same type and diameter as stock are permitted. The interchange of hydraulic and solid lifters is permitted."

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Chris Schaafsma


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PostPosted: Tue Dec 10, 2019 9:33 am 
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Joined: Thu Nov 07, 2013 2:47 pm
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Under level 2 prep-

f. Camshaft and Valve Gear
1. Camshafts are unrestricted. Any lifters, tappets/cam followers of the same type and diameter
as stock are permitted. The interchange of hydraulic and solid lifters is permitted.

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Jonathan Spiegel
Big Island of Hawaii Region and Colorado Region
FP/GTL Honda CRX


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PostPosted: Thu Dec 12, 2019 12:46 am 
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Joined: Tue Oct 27, 2009 9:33 pm
Posts: 166
Location: Aurora, CO
zChris wrote:
Did the rules change. I thought limited prep meant stock only lifters?


I think Miata people got the rules changed


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PostPosted: Wed Dec 18, 2019 6:23 am 
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Joined: Tue Sep 03, 2013 1:03 pm
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Location: Upstate SC near CLEMSON!
When I first built my FP Miata in 2004 I had to run stock hydraulic lifters per the then current rules. Engine has been freshened many times since then but always with the stock HLAs. I decided to finally build a new one and take advantage of the "rules creep". Don't know who pushed the change or when but I think it was several years back. In any event I think a FP Miata can use them legally. With the right cam, solid lifters should let the engine rev a bit more without floating the valves due to HLA issues.

Hadn't thought of grinding the lash adjuster when fitted to the top of a valve. Neat idea. I have been using my surface grinder for the shim over bucket shims.

Still in the evaluation stage at this point - as a low budget Regional guy have to figure out if the cost and effort would produce any meaningful results.


Last edited by HPMotors on Wed Dec 18, 2019 7:50 am, edited 1 time in total.

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PostPosted: Wed Dec 18, 2019 6:34 am 
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Joined: Fri Oct 01, 2010 9:21 am
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If you use anything more than mild lift, on a car (such as a miata) where the shim is on top of the lifter, you run the very likely risk of the cam lobe pushing the shim right off the lifter.

It's not a miata thing, it's a durability thing.

I don't like Miata's either, but this is a good idea, and has been for at least 10 years of prod class rules. When I built my POS miata in 2007 they were already legal.

Anyway, SuperTech has everything you need -valves, buckets, shims - all of it.


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PostPosted: Wed Dec 18, 2019 7:56 am 
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Joined: Tue Sep 03, 2013 1:03 pm
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Location: Upstate SC near CLEMSON!
Agree totally with modified cams spitting shims off of the top of the lifter - which is why I stuck to the old school hydraulics for so long. If I win the lotto, I would just skip all of this hassle and buy a front running pro built motor 8)


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