1G Mystery HLA pressure regulator

[talonsnwbrdr]

Hello all, please forgive if im not posting right and feel free to educate. I just got my head back from the machine shop for a basic top end rebuild (ill call that head A) and i have another untouched head sitting in the backround (ill call that head B). Head A i believe is from a 91-94 (I&E on cam caps), while head B i believe is from a 90 (R&L on cam caps). Anyway, i was looking at the hla pressure regulators of both and theyre strikingly different. Head A regulator is obviously stock (seen pics on the forums - oem evo III regulator post). But the regulator of head B looks more like the evo III one... except the "channels" on top look a little different, and instead of being flat on the bottom, theres a two inch long "cylinder" coming out the bottom with a big bolt in the end. Any ideas?
(ps sorry but ive only an iphone to work with, hence no pics and many words)

 

[romeen]

Don't know if this helps but this is the head off of my 6 bolt motor. AFAIK, the HLA regulator is the stock/original one.

 

[talonsnwbrdr]

Not really but thank you still. Is the bottom of that one flat? Or does it have the cylindrical piece coming off the bottom (any underside pics). Wish i could post a pic of mine would make it easier... Also, the top looks more like that style (visible "channels") as compared to the "smooth" style, if u catch my drift, but the channels just form a straight up "t" and it doesnt have the little wall of china around the outside edge. Oh and on two of the ends of the "t" theres ball check valves(looks like). One points at I4 cam cap, one points towards E5 cap (if u draw a straight line from it). Sorry i know this is a pain im just trying to b as descriptive as possible. Ill try hijacking a cpu so i can post some pics asap.

 

[romeen]

This is the only other pic I have showing only a portion of it. It looks to have a flat bottom. There is a casting on the exhaust side reading "R-(possibly a 1 or I)-2".

 

[justa4clturbo]

I have like 7 heads on shelf and one is all smooth on top and taller I think it came off jdm cyclone motor but might be wrong .....

 

[bastarddsm]

The smooth taller one is the JDM regulator. It supposedly lowers the pressure to the lifters. I run one, and have noticed significantly less oil in my breather tank. It also get a little more lifter tick when cold than with a usdm regulator.

 

[talonsnwbrdr]

Allright guys heres the pics finally, the reg on the right is the "normal" one, the one on the left is the one in question. never seen that long part on the bottom just flat

 

[talonsnwbrdr]

Resolved then? Jdm?

Yes... Lol thanks guys.

 

[kiggly]

The common one is on the right in the lowest picture. It is the OEM oil distribution block. There are a couple different versions, but they are all essentially the same. It just connects the oil passageways with no regulation or pressure reduction methods of any sort.

The one on the left with the bolt on the big bottom and plunger inside is the OEM mitsu regulator. It is a rare bird. Some DSM's did get this, but it seemed pretty random. I believe the 1989 colt GT's all got this. Its function is explained in the 1g DSM Tech manual's engine section. What is does is dump oil directly into the cylinder head to reduce the pressure to the lifters. It must have shown some advantage or no engineer would have ever been able to push it through to production at all. Then, cost cutting must have eliminated it for the simple distribution block.

The downside is this OEM part regulates by simply dumping oil into the head that all has to drain back. My part actively limits oil by a shuttle valve that cuts off flow to the lifters as pressure increases beyond what is needed. This results in zero waste oil to be drained back from the head due to regulate the pressure down to the lifters.

Thanks,
Kevin

 

[4g63t]

Would using a kiggly HLA keep less oil from going through my catch can system? My lines come into the vc above the baffles in stock location.

 

[evilb]

Bringing this back from the dead because I've found myself in a similar situation as OP. Im bringing a 1g talon back from the grave and I happen to posses both types of factory hla regulators. Is there a consensus on which is best or is the kiggly part bar none the way to go?