8 replies to this topic

[DES4]

Bought a used SM a few months back that I've been piddling with trying to get in shape for its first outing, an HPDE at the end of March.

Overall, I'm pretty satisfied with where I'm at with the car at this stage, except for the HLA clatter. A 90,000 mile motor that I'm reasonably certain has never been opened up (save for a timing belt) with very modest dyno numbers, it has valvetrain clatter that comes and goes regardless of temperature... although it seems to shut up entirely at higher (2500+) rpm.

I attribute it to the HLA's, as 90,000 means the car sat quite a bit (good oil pressure: 20+ at idle), but I guess a longshot could be valve springs (a few likely spent a lot of their down-time compressed). In any event, realizing this is a non-interference motor, and being that the previous owner had raced it in this state, I was figuring on putting up with it for a little while, at least until I decide whether I'd be replacing the head (as my first upgrade) once I make the move to competition.

So; is there an issue or concern as far as ignoring this noise? What about going from the 5W-30 currently used to a 10W-40 (aware of the HP loss) to help shut the little beggars up?

... and furthermore; is there a cheaper alternative to $22 apiece brand-name lifters?

[DamonB06]

Here is a link to the best deal on lifters I could find. http://www.store.par...uct974.html#974

I replaced all mine while I had the motor out and they still clack after the car has been sitting for a week or two. If I let the car warm up sufficiently then shut it down, it wont do it on the next start. I have read that others have the same issue. I think the consensus is to just ignore it. Searching will pull up some other threads on the matter.

[Keith Novak]

The sewing machine noise is well known in the miata. I think it was miata.net where I remember people using heavier or lighter oil to cure HLA noise. Racing...you can't hear the noise at WOT and you don't want to base your oil choice on lifter noise. I put about 20 races on a brand new crate motor, changed oil every weekend and it still has a bit of a tick. It's not fatal.

[LarryKing]

FWIW - in my experience synthetic oil results in more lifter noise than dino oil.

[KentCarter]

Here is a link to the best deal on lifters I could find. http://www.store.par...uct974.html#974

I replaced all mine while I had the motor out and they still clack after the car has been sitting for a week or two. If I let the car warm up sufficiently then shut it down, it wont do it on the next start. I have read that others have the same issue. I think the consensus is to just ignore it. Searching will pull up some other threads on the matter.

Technically, these HLA's are not legal unless the box they come in reveals they are OEM Mazda parts (Blue Mazda writing, etc.) Kia HLA's are not legal.

[Randy Thieme]

With my car if I take it in and out of the garage a dozen times, running the engine just a minute or two each time, eventually it will develop HLA noise which does not go away within a few seconds of starting. Since mine is still sort-of street-legal the cure is to drive it around for a couple miles or more.

[Alberto]

What oil is in the motor? My motor, also 90k street miles, made less noise after a couple of flushes with cheap Pennzoil when I first acquired it. After that point I switched to synthetic racing oil (Redline 30 weifht) since the car wasn't being driven on the street.

[DES4]

What oil is in the motor? My motor, also 90k street miles, made less noise after a couple of flushes with cheap Pennzoil when I first acquired it. After that point I switched to synthetic racing oil (Redline 30 weifht) since the car wasn't being driven on the street.

Bought it with a Shell synthetic 5W-30 (says the prior owner); car was occasionally maintained by a local Mazda raceshop here in central FL. I have one change with Mobil 1 5W-30 in it now. I've only been running in the car on the street (trips to the shop and back), trips less than 20 minutes with very little hard acceleration; maybe some track time will have a positive effect...?

[Jim Boemler]

Technically, these HLA's are not legal unless the box they come in reveals they are OEM Mazda parts (Blue Mazda writing, etc.) Kia HLA's are not legal.

Well, the Kia HLAs are in fact Mazda OEM parts. It's not clear to me whether the color of the box they came in is significant to the rules, any more than what dealer you bought them from, what boat they arrived on, etc. Given the pretty large price difference, it wouldn't surprise me if more new HLAs in SMs came from Kia than from Mazda.

BTW, it wouldn't be impossible for the CRB to allow specific replacement parts in addition to "Mazda" parts, and these would be a good candidate.