HLA vs SUB in BA Astinas
 

"No BP engines fitted to Proteges/Astinas had solid buckets in Australia. Both the '96 and '97 engines in my garage have HLAs."

Or so I though until I actually was imformed by Edwin (The Man) that I was incorrect. So:-

HLA vs SUB

Discuss!

p.s. HLA = Hydraulic Lash Adjuster, SUB = Shim Under Bucket.

Thank you for starting this thread.

Please understand that those automobile articles you read were wrong:
http://www.axela.mazda.co.jp/spec/sp...?link_id=axlnv
If you look under the "20S-SKYACTIV" and "20C-SKYACTIV" columns, you will see that the Axela's Skyactiv engine's compression ratio is 12.0:1. Look under "圧縮比" (which means "compression ratio" in Chinese and Japanese) is 12.0. I think explained in another thread that the reason for this is because of the limited space for the sophisticated 4-2-1 exhaust manifold. A more compromised exhaust manifold design was necessary in order to clear the exhaust tunnel in the BL Mazda3/Axela's floor pan. This New York Times article has probably been the most accurate article regarding the compression ratio discrepancy so far: https://www.nytimes.com/2011/11/13/a...ef=automobiles
The compression ratio differences will only apply with the CX-5 and future vehicles utilising this engine. The CX-5 will be the first purpose built vehicle to fully take advantage of the SkyActiv technologies, so that means they can safely use the 14.0:1 compression engine if they want. Again, it is just technically impossible to do so reliably/safely on the BL Mazda3/Axela. The lack of exhaust scavenging causes elevated combustion chamber temperatures which prevents the use of higher compression as that will likely lead to preignition problems.

I will address this very subject in the next update of the FAQ. The only information I had obtained so far are off service manuals and parts catalogues. I am still waiting for my contact at Mazda USA to send me more technical materials regarding this engine.


It is strange that your 96/97 Astina engines have HLAs because my Aussie parts catalogue shows otherwise:
https://lh5.googleusercontent.com/-2...0/astinaBP.jpg
This is the earliest build of the "series 3" BA according to my Aussie BA VIN list. It is an Aussie VIN, because it starts with "JM0". Feel free to verify this if you like. :) Now on the other hand, the series 2 (1st generation) MX-5 always had HLAs up until the last ones were built in 1997... only the BPs fitted in the BAs were first cars equipped with the solid lifter valvetrain.
I will delete that pic in a day's time.


I am sure there are other minor errors in the FAQ. I had corrected them whenever I saw them. But if you see anything else you maybe concerned about, please point it out and I will duly research the issue to verify the concern. This is not a trust concern, but as a policy that I verify all information I come across in order to maintain the quality of accuracy of the site. :)

BA P3 have bucket and shim ---- correct The Man.
Be careful posting the above photos and copies of workshop manual ,aren't they held by copyright laws.
skyactive I don't know about as I don't work in workshop any longer but the techs have done training on them and I can access the info if needed.

don't worry, that pic will be gone after tomorrow...
but believe me, I'm not the only one that post pics of the parts catalogue... others have done this; mazda parts professionals at that! As far as I'm aware though, pics such as those operate under the "fair use" clause under US copyright law... being I'm in the US, those are laws I fall under... I'm no lawyer of course :)

I'm very aware of the copyrighted materials of course... I don't post copies of any of the shop manuals I have. The most I could do is provide a publication number and tell people to go buy it ;)

I appreciate the concern though, they have been duly noted :)

I have access to the US Skyactiv training materials and the new model guide for the 2012 Mazda3... but beyond that, it takes some diplomacy...


*continues quest to find early BG non-catted BP camshaft specs*

Oh nos, so much fail on my behalf. I better go take a closer look sometime. Sware they were HLAs. Also puts into question whether or not I have the correct camshafts for my engine or not. Crap not I have to open up the engine just to find that out. Fail!

the BA solid lifter cams have "BP2Y" stamped on them (both cams)... the HLA cams say BP05/BP06 of course ;)

keep up the work... feedback is what makes improvements possible... one thing I will say that won't happen anytime soon is how the site looks... too much effort involved to overhaul the site to be more user friendly... unfortunately, everyone will just have to live with how it is indefinitely.... there's an old saying, "beggars can't be choosers" right? ;) I do try to make minor improvements where easily possible at least!

Yeh a mate of mine gave me tighe cams which were hla type so I can't use em in my shim motor. Have to get em reground or fit hlas which I havent bothered finding out if valves are the same hla to shim.
It is real hard to see em under the cams you can only see a light line around the outside of the shim type.

the only real discernible difference was the length of the valve stems between the HLA and solid lifter BPs... the HLA BPs uses a shorter valve stem, while the solid lifter BPs uses a longer valve stem... the difference is probably about 2mm... the valve keepers and retainers are also different between these two variations of the BPs... parts are all interchangeable regardless, to an extent
solid lifter valve retainers left, HLA keeper right:
http://www.solomiata.com/images/spri...nercompare.jpg
shim & bucket left, HLA right:
http://www.solomiata.com/images/liftercomptop.jpg

more to learn here: http://www.solomiata.com/Mx5Engine.html
beware that only BP information is accurate... I found myself information for other engines had some misinformation... I tried contacting that bloke years ago but he disappeared and doesn't care about that site anymore :(

I'm sure you're already aware by now that you can't fit the HLA into the solid lifter valves as it will squish down the lifter cause no ability for the HLA to automatically adjust the lash... but you can use the shim and buckets into the HLA valves, you just need very thick shims, that's all... why you want to do that is beyond me

other than that though, the head is for all intents and purposes, the same :)

That's what I thought but I CBF looking into it ,I have been looking for a HLA motor to steel the head from . Have thought about the regrind ,but my motor has nearly had its day. Might be time for some sort of hybrid motor/BA combo.

are those performance HLA cams you have? if they are, what are they worth? You might be better off getting solid lifter cams designed for the NB MX-5... they did come with more aggressive factory solid lifter cams too of course :)

Poop! 2Y on the cams for the old Nov97 built Astina.

Currently has a engine from the 96 in there. So could be solids in that also.

Looks like some NA8/Early CBA8P cams will be up for sale soon.

X2 ( set of Ivan Tighe cams as well ) remember something about they were the 805 grind - his laser went well with them in revved hard and pulled better as well

805Cs they would be then.

Yeh sound about right .anyone got a BA HLA motor going real cheap?

Okay you awesome two, you both have been really helpful so far.

Can you tell from the engine number if an engine is HLAs or shims?

All I know is that the current engine is from a 96, but if it before May or after May? That I don't know. And don't wanna pull the engine cover off if I don't have to.

if you have the VIN from the car that the engine came from, I can look it up
mazda engine numbers never really had much meaning to them... at least nobody has been able to figure out so far.... it will be mid to late 96 that the change over occured

you have no idea how long it took before people started using the engine designation codes properly after I figured out Mazda's system, which is very similar to Nissan's

can you look through the oil filler hole to see if you can look at the lifters? a strong torch might help

No VIN. Might try looking down the oil filler. But I doubt I'll see much.

Might just have to bite the bullet and pull the cover. Buy a new seal for $30.

This way, least you'll be sure ;)

if the gasket is still pliable, you can probably get away with reusing it... done it before without problems :)

had a look down the oil fill hole. i think i have solids still, but not 100% sure as it is near impossible to see much.

but i think i can see the outer tube that the solid have and the cams have the same wear marks on the lead edge of the lobe as the previous engine i have checked.