thinking 16v astron head

[rx22nv]

My god, a real HKS twin cam head? In Australia?

Yeah, someone has to copy it for the good of the community.

[geezer101]

There is a LOT more involved with this than just casting a head and sticking a heap of valves in it. Billet cams, rocker rail assemblies to accomodate the reconfigured valve train set up, rocker cover, gaskets, cam sprockets -the ignition system? It is huge. That is why someone wants $10k to go into making one. The cost of building a really HI-PO 2.6 litre engine with one of these babies sitting on top would double. The picture of the HKS head I've seen looks similar to the Yamaha twin cam head used on old school Celicas (the real Celicas before they became fat pigs) but are more compact. The 4G54 HKS head is a freaking work of art

[rx22nv]

For sure, the fiddly bits would be the hard part. But send them to china for replication.

Bottom end isn't going to be that expensive, rods, pistons, bolts and balancing.

Hopefully the magna dizzy would fit ( didn't look where the dizzy went) and can be used as a crank and cam position sensor like I currently have setup. Microtech lt10s and individual coils and away you go. Cast/machine them with astron II intake pattern and standard exhaust pattern and this would keep the costs way down on a conversion.

It isn't really worth it financially but the cool factor is priceless.

[Superscan811]

Dizzy comes off the exhaust side.


Cheers.

[geezer101]

Thanks superscan for the pic. The bottom end is stock - isn't it? I mean, HKS intended it as a replacement performance head. There would be some differences with the timing chain components but that would be about it. Imagine seeing that under the bonnet of your ride

[A112H]

There is also a pic n this thread of the 4G54BX

http://www.sigma-galant.com/viewtopic.php?f=24&t=3303

And then there is this one http://i237.photobucket.com/albums/ff39 ... 003zf8.jpg

And here we go again in 2010
http://www.sigma-galant.com/viewtopic.p ... 02&start=0

Seems to me about every 2 years someone asks, everyone finds pics and dreams about what could have been and that is about as far as it goes, ever.
From what I have found it seems they made about 280ps so about 200kw.

[webby]

The picture of the HKS head I've seen looks similar to the Yamaha twin cam head used on old school Celicas (the real Celicas before they became fat pigs) but are more compact. (

Yamaha made/make all of Toyota's twin cam heads AFAIK, not just the 18RG/2TG heads. I know they were still providing heads for at least some engines up until at least 2009 (the 2ZZGE head was a Yamaha jobbie), not sure about after that though.
Interesting semi-related thing which is possibly a fact, I've been told that the valvetrain used in the WR450F is interchangeable with that of a 20v 4AGE.

Agreed that the HKS head is a work of art, it's a shame there's so few of them and that they're so fkn expensive

[Superscan811]

The bottom end is stock - isn't it? I mean, HKS intended it as a replacement performance head.

I don't think the bottom end would be "STOCK" , but I do believe it will bolt up to a standard block.

There would be some differences with the timing chain components but that would be about it.

Most likely the only difference would be the length of the chain (and 2 cam gears of course).


Cheers.

[Cottees]

Yamaha made/make all of Toyota's twin cam heads AFAIK, not just the 18RG/2TG heads.

IIRC, Yamaha did the 1JZ and 2JZ heads. The 1JZ head I saw the other day does look very similar to the HKS head.

One thing I should say is the 1JZ and 2JZ heads have upside down cap looking things sitting on top of the valves, and the cam mounts are parallel to the heat instead of coming out at an angle. I have also seen this type of head on a Suzuki G13B.

[Cottees]

1JZ




G13B

[mic_77]

Once you have the basic design you can change things to make it more economical like everything out of a 4g63 head just get the cams made in billet with different spacing that would help to cut costs.


Cheers Mic

[geezer101]

Judging by the additional pics supplied there is also a different designed timing cover too FYI I didn't mean a 'stock' engine but would work with standard internals (if you were a cheap ass, or stupid ) If suddenly one day I woke up and owned a bank or an oil field I wouldn't just 'copy' the HKS head but retool it so it could be used in either FWD or RWD (location for CAS either front or rear and a distributor slot) and have the inlet side prepped for Astron I and II manifolds. I'd bet the previously unloved Astron motor would become very poular and you could bolt one of these gems onto any 4G52/54. Stuff of dreams though people

[Superscan811]

Judging by the additional pics supplied there is also a different designed timing cover too

I'm not too sure. It looks standard under all the added stuff.

FYI I didn't mean a 'stock' engine but would work with standard internals (if you were a cheap ass, or stupid )

I wouldn't just 'copy' the HKS head but retool it so it could be used in either FWD or RWD (location for CAS either front or rear and a distributor slot)

Wouldn't bother with a cam angle sensor, I'd go straight off the crank as it will give a more accurate position of where the piston is.
Also, twincam technology has come a fair way in the last 20 years and as you said, there are better ways to do the job now..

and have the inlet side prepped for Astron I and II manifolds.

Again, I wouldn't bother, the angles would be far from optimal and to make an inlet manifold isn't particularly difficult or costly.

If you were going to purchase one of these heads, the cost of the manifold would be insignificant. Have a look at the ports on the twincam head, they are all facing up slightly where as in all the astron heads, the ports face down.
Getting straighter ports and runners can only help with this air flow.

INLET



EXHAUST



The tighter the bend, the less air sucked into and pump out of the engine.


Cheers.

[mic_77]

A Ross balancer with a crank angle sensor is already available albeit by custom order. You can even order it with a drive for an external oil pump or fuel pump if you desire takes car of that problem.
It is funny that this has popped up now as there is a billet 8v head that is receiving the final touches at the moment.


Cheers Mic

[A112H]

Is it just me or do the exhaust ports look like a DOHC 4G63 manifold would fit?



Inlets don't look that far away either

[geezer101]

Maybe one pinched the design from the other? They're pretty close...

[Cottees]

The DOHC 4G54 was used in the 4WD Starion.


Engine Specifications:
Engine: 2314cc Inline 4 cylinder (HKS134E destroked 2.6L G54B to 2.3L)
Bore: 91.5mm
Stroke: 88mm
Compression: 12:1
Pistons: HKS custom forged pistons
Head: DOHC 16 valve
Fuel: Two Solex 50mm carburators
Induction: Naturally Aspirated
Power: 276 hp @ 7000 rpm
Torque: 195 ft/lbs @ 5500 rpm
Lubrication: Dry Sump
Cam: HKS custom camshafts (intake = 288° / exhaust = 288°)
The “HKS134E” engine was based on the G54B engine found in many of the Starions that were produced. The insides differ greatly from those of the stock engine. The engine has been destroked from 98mm to 88mm resulting in a 2314cc of displacement. HKS also made their own custom forged pistons for the engine. The head is made by HKS as well and is DOHC with 16 valves. The engine was non-turbo and carburated making 276hp @ 7000rpm and 195 ft/lbs @ 5500rpm. This resulted in a high reving rotary like power band.

http://groupbrally.com/?page_id=29

[geezer101]

I saw the bio on the HKS Starion last night - maximum BRUTALITY Funny thing is, other than the drastic weight reduction and composite panels (and that killer engine), the HKS Starion is a collection of off the shelf stuff from the mitsubishi parts bin - aka backyard engineering. Now somebody build that engine so we can sleep at night...

[A112H]

Where is this bio geezer?? Link us up some bio love damn it.

[geezer101]

Cottees created his post with the data from the HKS Starion - he left a linky link at the bottom of it http://groupbrally.com/?page_id=29

[Cottees]

And this is the original article :
http://www.pri.nir.jp/~yd24gsr/page/sta ... hks4wd.htm

[A112H]

This is the best bit

最大出力
２８０ｐｓ/７０００ｒｐｍ
最大トルク
２７ｋｇ・ｍ/５５００ｒｐｍ

[geezer101]

...anyone speak 'box head'? Methinks there is translation issue....

[RaptorReed]

http://classiccolt.forumcircle.com/view ... 30&start=0

[mic_77]

This could change things will have some flow figures soon.





cheers Mic

[mic_77]

And a stud girdle to strengthen things up.



cheers Mic

[mic_77]

Sorry for the crappy pics will have some more in depth pics soon.

Cheers Mic

[A112H]

Is that head sohc or dohc Mic, can't tell from the pics

[mic_77]

It is a single but with a lot of improvements the test pieces used for modeling easily out flowed a heavily ported head. It still utilizes stock manifolding but all ports have been raised and straightened good news is water still flows through the head so it can be used in multiple applications. Best thing is it won't warp and crack under heavy load which becomes an issue when you are pushing more then 500whp. There should be one up and running in time for compact attack 2013. Valves are also bigger than any used in a stock style casting. Will be very interesting to see how they come up and I would like to see how they go N/A.

Cheers Mic

[A112H]