28 replies to this topic

[S pack]

2811930 Holden Frankenstein casting just those that have never seen one . Application very late HG/ GTR in adjustable from HQ to HJ in non adjustable. YES it came out both. this head is a 202 casting with earlier 186 machining and large plugs dated 15/4/71  

Dave, a 2811930 head was low comp 173 and high comp 202. The high comp 173 head used on 173s GTR was casting 2811929. 

 

So that 2811930 head came off either a HG commercial vehicle, a HQ or an LC Torana with a low compression 173.

All in all still a rare puppy with adjustable rockers.

Edited by S pack, 16 August 2013 - 08:56 AM.

[Dr Terry]

I've seen head casting no. 2811930 dated as early as March 1971, so they were very common in the last several months production of HG 186 (because the 186 was the most common engine fitted) as well as HQ/LJ 202.

 

It appears the casting was so designed that it could be machined for large spark plugs & adjustable rockers (186) or small spark plugs & fixed rockers (202).

 

Dr Terry

[S pack]

Dave, when HQ production commenced the HQ commercial vehicle range was still months off, so Holden continued producing HG utes and vans, so these HG commercial vehicles got 173 and 202 engines.

[Dr Terry]

The way it is explained above is a little confusing. I'll see if I can simplify it.

 

Firstly, normal (HC) 186 & 202 heads shared the same (large) sized combustion chamber, it's only the spark plug & rocker gear that differs. Head casting no. 2811930 was used in both applications, it was just differently machined when the HQ went into production. So basically, ALL late (3/71 on) HG 186 motors had the same head casting number as 202 engines in HQ, HJ, LJ & LH etc.

 

Where the commercial vehicle bit comes in, is that the last 4 months of HG van & ute production (after the HQ sedans & wagons were released) used 173 & 202 engines instead of 161 & 186 engines. These HG 173 & 202 engines had small spark & non-adjustable rockers, they were really just HQ engines with HG sumps etc. This really has nothing to do with the use of 2811930 on late 186 motors.

 

Also a lot of mention is made of low compression motors, but these were very rare in the day & ultra rare these days. I have to say in my 40 plus years in the motor trade, the number of low compression Holden sixes I've seen is in the single digits & I've never sighted a 186 or 202 low compression motor.

 

Dr Terry

[Dr Terry]

Yes, that's correct, LJ GTR was just a stock 202 so it had the 2811930 head, with the later rockers & spark plugs.

LC & LJ XU1s had the 2815843 head.

Dr Terry

[S pack]

Your cylinder 2811930 head was originally cast for use on a low compression 173 or a high or low compression 202. It is the pistons that determine if a 202 engine is high or low compression.

Your 202 engine will be high compression if the engine builder has used the correct pistons.

Sounds like your cyl head is one of those early production oddball 138, 173, 202 heads that had the 149, 161, 179,186 type adjustable rockers.

I don't know for sure which valve pushrods you need for this head however I expect it will be the longer 149, 161, 179,186 type.

I can't remember the lengths of either type off hand, I will need to look it up when I have more time. Dr Terry will probably know.

 

Cheers

Dave.

Edited by S pack, 17 January 2020 - 11:34 AM.

[Dr Terry]

Holden Red 6-cyl with adjustable rocker gear use the longer (9.136-inch) pushrods.

 

The fixed rocker gear requires the shorter (9.00-inch) pushrods.

 

Dr Terry

[yel327]

I know it’s a 7 year old post Terry but I’m surprised you didn’t see many low comp engines. Every CF Bedford with a 173 was low comp, I would have seen 100’s of these. I’d also have dozens of low comp 202 powered commercials recorded but I wouldn’t have looked at many of the engines, just recorded or took photos of the tags. The ones that have particularly eluded me have been 186L, QS and BV. I think I saw a 253L once but an old memory and the odd BS. The really rare ones would be GE, GM, HE, HM and the XQ or XZ examples. I don’t recall ever seeing a ZM but I think I have an L23 plated HZ recorded. Will check.
I’m sure you told me once you saw an 11QS, wouldn’t be too many of them.

Edited by yel327, 17 January 2020 - 01:33 PM.

[Dr Terry]

It was all a matter of where I worked & on what type of car. In my first job I saw a lot of hire cars & taxis. I saw a few low comp Falcon 6-cyl & that 11QS Statesman engine, strangely very few lo-comp Holden 6-cyls.

 

When I had my business on Parramatta Rd in the late 70s & into the 80s, I think most of the CF Bedfords that I saw had V8s fitted. The few stockers that I saw had 202s in them.

 

There is a good chance that I saw more lo-comp motors, but like most guys I take more notice of numbers & ID tags etc. nowadays, than I did 40 years ago.

 

Dr Terry

[yel327]

Just checked.
8 x L23 plated, all commercials except for a single 8/77 HX Belmont wagon. Latest an 11/79 HZ.
14 x L21 plated, latest one a really late HJ.

Most are either Kiewa Grey or Shell Grey, but a few others in white or chamois. So mainly Fleet.

[yel327]

The first CF’s with Holden 6 were all FE prefix afaik. My Dad bought one of those as a milk truck. 3spd in the floor using an Aussie 4spd shifter. The later ones with 202 were FL prefix. My Dad had a pantec in one of these too, it was a Trimatic. I think they changed to the 202 after the end of HJ.

[claysummers]

Mate had a 173LC HQ Belmont wagon in 1980. Don't think it was fleet but could have been being a Belmont.

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[yel327]

My Dad also had a HQ Belmont Ute, 173 3spd. Can’t remember if it was a low or high comp. The HQ wagon we had was a 202HC. I also had two HQ Belmont vans and a HQ cab chassis, all 3spd manuals. One van was 202HC and the other two were 173HC. They were all white apart from the wagon which was Russet.
From what I have found so far collecting data for 1000’s of HQ-HZ the low comp engines were primarily in Holden or Belmont models (mainly commercials) and mostly in Fleet vehicles. I’m not sure what the big shift was in 1976 that saw the low comp engines all but disappear even from CF Bedford. Dr Terry might have more info. Maybe the low comp engines didn’t work as well with emissions gear?

[RallyRed]

I'm guessing no one ever saw one of these in the flesh.............

Attached Files

•  186__DIESEL_Holden_Red_Motor__Oct_2017-2.pdf   922.02K   36 downloads

Edited by RallyRed, 18 January 2020 - 05:35 PM.

[I'm a Red Motor fiend]

Thats a great read Col. The elusive heron head. Saw a claimed one for sale recently, wanted $15,000.

[yel327]

Imagine how horrible a diesel red 6 would be? I remember how horrid a standard HQ cab chassis with 173, 3spd and 3.55 rear axle was. HJ with 173 or 202 with 3spd and 4.44 was even worse. Almost halve the hp and they’d be woeful.
I love how they tried an Olds 350 diesel V8 in a Statesman but it was as slow as a Statesman with an Opel big block 1.9 and used similar fuel amounts.

[claysummers]

Yes a bizarre concept. Quite a few valiants in South Africa and New Zealand with diesels I believe.


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[Dr Terry]

 I’m not sure what the big shift was in 1976 that saw the low comp engines all but disappear even from CF Bedford. Dr Terry might have more info. Maybe the low comp engines didn’t work as well with emissions gear?

Lo-comp engines were made to accept standard grade fuel. The availability of standard grade fuel diminished dramatically during the 70s. As a matter of fact it disappeared entirely in the early 80s, about 3 or 4 years before unleaded was introduced.

 

As such lo-comp ADR27A engines are quite rare. Given the power loss already associated with ADR27A they were virtually ignored & sales dropped to zero.

 

AFAIK lo-comp versions of Blue motor 6-cyls appear in engineering data but didn't go into production.

 

Dr Terry

[yel327]

I remember the Standard and Super bowsers in the later 70’s. The low comp engines are still in the HX and HZ Features and POA manuals. Application as follows in HZ:

L21 - export only and only with delete exhaust emissions controls (delete ADR27A). LD1 is the same. Both do say available with XT5 engine equipment, but that will just be getting ready for WB I think. Date for this info appears to be May 17 1978, and possibly March 23 1979 for the XT5 bit. It looks like “cancel as soon as possible” was added to L21 at some stage too. LD1 has the same revision on March 23 1979, which I think is the XT5 bit.

L23 appears to be available on every model in Holden, Kingswood and Premier luxury levels except for cab-chassis and Sandman. Premier usage is as per L21 though, ie export only and with delete ADR27A. Plus it appears L20 remains optional on Premier although L32 became standard during later 1978, no “export only” caveat on L20 Premier.

HX is pretty much the same except L33 is still there but for “Engineering Records Only”.