186 or 202 - which is the better engine

[pfillery]

I had heard in a few places that the 186 was a far superior engine to the 202 for converting a Landy. Is this correct and what is the reason why?

Additionally, how can one ascertain whether a holden cylinder head is a 186 head or a 202 head - apparently you can fit a 186 head onto a 202 but not the other way around, so how can I tell if the head on my 202 is a 202 head or a 186 head (the head has been rebuilt for ULP LPG so if it's a 186 one would be worth keeping as a spare for my 186)

[bee utey]

186 heads have flat seat plugs, 13/16" hex. 202 heads have taper seat plugs, 5/8" hex. The 202 also has non-adjustable rocker posts unlike the 186 which had nuts to screw down the rocker posts. The 202 used to be known for cracking pistons and then throwing rods, 186's less so. My brothers original HG 186 panel van broke a piston 450km from home, that was fun. My neighbour's HQ 202 broke a piston at around 80,000 miles. Any reconditioned motor with non genuine pistons would be unlikely to suffer like this though. !86's are shorter stroke, easier to get revs out of.

[shorty943]

I would also suggest finding a genuine 186S, as these engines were naturally higher revving than the stock 186.

I also agree about the 202 being susceptible to throwing rods etc.
Was an RAA mechanic for some time, a chap came into my garage, said his engine was "knocking" and the alternator light had come on.
A quick look found the problem, # one rod had knocked the alternator off. :eek:

[frantic]

One other thing is 202's overheat easier where a 186 can handle a bit more heat/ poor cooling like when I used to have a SIII 88 with a 186 and the radiator rusted through the bottom tank, made the engine so hot it would not stop running when I turnt the ignition off so I had to stall the motor! Got a new radiator and she started first go and ran perfect till I sold it. Only prob.I had was it did not like water, even heavy rain and the engine would die, but that was more poor electricals.
One other warning they have lots more power than the LR engines so can snap rear axles in LR diffs.

[Bigbjorn]

The 202 and 173S had 9.4:1 compression ratio, the highest CR of this engine series. If you fit a 186 head to a 202 block then the CR may be a bit much to run properly on 91 unleaded and you may have to use the expensive stuff. As to revs, the 202 was used in the GTR's with option XU1 and ran up to 7,000 rpm for 500 miles at Bathurst. All to do with having the right internals and preparation. Get the rods and crank from a blue engine. Any decent crankshaft shop can do the relatively minor mods required to fit the fully counterweighted crank into a red engine. Use quality forged pistons and away you go to rev its ears off.

[rick130]

The 202 and 173S had 9.4:1 compression ratio, the highest CR of this engine series. If you fit a 186 head to a 202 block then the CR may be a bit much to run properly on 91 unleaded and you may have to use the expensive stuff. As to revs, the 202 was used in the GTR's with option XU1 and ran up to 7,000 rpm for 500 miles at Bathurst. All to do with having the right internals and preparation. Get the rods and crank from a blue engine. Any decent crankshaft shop can do the relatively minor mods required to fit the fully counterweighted crank into a red engine. Use quality forged pistons and away you go to rev its ears off.

Yep, totally agree, or use Starfire rods out of the 1.9 litre OHV four cylinder, they are basically XU1 rods.

The 202 also makes better torque, you can't beat cu.in. IMO.

[Bigbjorn]

Yep, totally agree, or use Starfire rods out of the 1.9 litre OHV four cylinder, they are basically XU1 rods.

The 202 also makes better torque, you can't beat cu.in. IMO.

The blue engine used the so-called "Starfire" rods.

[tailslide]

From one who has been stuck on the side of the road...:wasntme:
The standard camshaft gear on the 186 was fibre (made from cloth and resin) to reduce the gear noise. It doesn't like the hydraulic lifters pumping up at high revs. There are aftermarket aluminium gears available which are stronger.

We had the 186 in a 2a and a 202 in my brother's series 3, the 186 was plenty strong enough to break rear axles. We preferred the 186 over the 202.

Cheers
Ron

[Jeff]

I had both, but they were in such different condition it would be hard to compare. The 202 was freshly reconditioned and ran beautifully, the only problem was the distributor drive gear, which was nylon and stripped so was replaced with a steel one from a 186.

The 186 I had was quite worn out and ran on LPG and petrol and would struggle to top 95.

The age of these engines now would mean the condition would be more important than the model.

Jeff

:rocket:

[Fluids]

Many moons ago a close friend had a IIA with a 202 and big fat sunnies/tyres ... he drove it like he stole it ... everywhere!! ... even offroad. He replaced the gearbox once (I wonder why :angel: ) but the engine never said die. It used to overheat regularly due to the crappy cooling system.

The only problem I could see, compared to my then 4cyl SIII softop was that it had no torque down low. You had to rev it to make HP & torque, and by that stage it was wheel spinning, and anything low speed offroad was more of a buggy run :eek:

On the beach it was foot in all the way ... my SIII would just chug along (on 7.5x16 wranglers). We swapped wheels one day and tried a beach run ... he just burried the thing constantly because it just wheel spun constantly, and my little 4cyl didn't have enough grunt to spin the massive wheel and tyres and hence would also get stuck.

I'm not a holden expert, but wouldn't a 173 or 186 be a better choice than a 202 ? (for offroad ... onroad is a different kettle of fish)

... and his 202 would scream its tits off onroad ... bad choice for a series lr imho.

[rick130]

[snip]
I'm not a holden expert, but wouldn't a 173 or 186 be a better choice than a 202 ? (for offroad ... onroad is a different kettle of fish)

... and his 202 would scream its tits off onroad ... bad choice for a series lr imho.

It all comes down to cam choice, then everything else revolves around that.
The 202 has a longer stroke and obviously more cc's than the 186 so to me that says it's ultimately able to make more torque at a given rev point.

[Davehoos]

blue 2850 is the best choice.counterwieght crank-12 port head.
reduced bearing cleances.EFI 3300 was very good at producing usable power .the 3300 black was OK but cranks and valve guides tended to fail at the end like a build quality issue--I did lots under warranty.easy to check when rebuilding.

186 didnt have the steel crank-many say it was in the 186S but ive not found that to be true.149 all had steel cranks.metal timing gewrs was a factory option.XU1 had better oil pumps.

149 and 161 was the engine of choice for pre 1975 conversions to bypass rego issues in NSW by government and councils..the engines some times are latter replaced with bigger versions.

!79 HP was the engine of choice for rebuilds.small block mods are needed to fit blue/black cranks.

american chev was called starfire as well i think people get these confused.starfire blue internals are much improoved.

australians like tourque but i think the smaller blocks are better.
compratio is a non even-lots of different types but the black is best for shape and learn how to adjust rolla rockers and solids.

[rick130]

blue 2850 is the best choice.counterwieght crank-12 port head.
reduced bearing cleances.EFI 3300 was very good at producing usable power .the 3300 black was OK but cranks and valve guides tended to fail at the end like a build quality issue--I did lots under warranty.easy to check when rebuilding.

[snip]


Dave, getting off track here, but I've read that the 2850 blue block is the best for a performance build up (well in excess of 200HP) when bored out as it has better core thickness than the 3300 block.

[russellrovers]

blue 2850 is the best choice.counterwieght crank-12 port head.
reduced bearing cleances.EFI 3300 was very good at producing usable power .the 3300 black was OK but cranks and valve guides tended to fail at the end like a build quality issue--I did lots under warranty.easy to check when rebuilding.

186 didnt have the steel crank-many say it was in the 186S but ive not found that to be true.149 all had steel cranks.metal timing gewrs was a factory option.XU1 had better oil pumps.

149 and 161 was the engine of choice for pre 1975 conversions to bypass rego issues in NSW by government and councils..the engines some times are latter replaced with bigger versions.

!79 HP was the engine of choice for rebuilds.small block mods are needed to fit blue/black cranks.

american chev was called starfire as well i think people get these confused.starfire blue internals are much improoved.

australians like tourque but i think the smaller blocks are better.
compratio is a non even-lots of different types but the black is best for shape and learn how to adjust rolla rockers and solids.
hi i have i79 balanced crank ex eagers own land rover which was in a 80 inch he used on straddi for sale

[Davehoos]

2850 bored with 186 oversized was common and easy to get.
it ticks all the boxes----engine number-ADR27C.