FE-FC Holden Discussion Forum

Technical Board => Modification Help => Topic started by: EffCee on September 21, 2010, 06:25:19 PM



Title: 186 vs 202 differences
Post by: EffCee on September 21, 2010, 06:25:19 PM
I have a 202 that has flat top pistons and has had the engine number ground off as well as the size of the engine. This was done as the engine was built by an engine company that sponsored a speedway car, so that the engine couldn't be used in a road registered car. The rego authorities here in the ACT don't really want to know about it. I will need another block, so this prompts me to ask the question:

I have a 186 block that is in good condition, so I was wondering will the components from the 202 fit into the 186 block, if not what will I need to change? I realise that the cranks are different, but was wondering if it is possible to fit a 202 crank into a 186 block and therefore all the components

Keith


Title: Re: 186 vs 202 differences
Post by: oldjohnno on September 21, 2010, 07:08:02 PM
The cheapest option by far will be to scrounge around for a good 202 block.
The 202 pistons are shorter than the 186 ones so won't work with the 186 crank, even though the bore size is the same. And the 186 cranks have a smaller main journal diameter so the 202 crank won't just drop into your 186 block without a lot of machining. Rods, cams etc. are interchangeable. If you can find a 202 that hasn't been excessively overbored (most you come across these days are already +0.060") you can just swap over all the good bits from your old motor. A blue or black would be nice because they came with Starfire rods (if your old motor doesn't already have them) but keep in mind that if you use a later block then technically you'd be required to use the corresponding emissions controls.

ps. Go Tux!


Title: Re: 186 vs 202 differences
Post by: brett_f on September 21, 2010, 09:19:47 PM
Effce,
if you were to use the pistons or in fact complete motor, the pistons are technically high compression and unless you use a low comp head it will give you pinging using the gas we have at the pumps.Not a good idea. You will need to use a low comp head if you want to run unleaded. Red motor heads have a H for high comp or L for low comp on the top side of the head near the rocker cover. This is the side the head bolts are visible.
Hope this helps.
Brett


Title: Re: 186 vs 202 differences
Post by: colt on September 22, 2010, 04:49:50 PM
Keith, I've got several sets of pistons and cranks from smaller reds if you need some bits. I've got a set of blue 3.3 .060" pistons, and standard journal cranks from the smaller motors. 202 pushrods are longer as well, I'm not sure where the extra length is made up, maybe the deck height of the block?

Colin.


Title: Re: 186 vs 202 differences
Post by: oldjohnno on September 22, 2010, 05:59:24 PM
...202 pushrods are longer as well, I'm not sure where the extra length is made up, maybe the deck height of the block?

Colin.

The deck heights are all the same; it's the type of rocker gear that determines what length pushrods to use. Late rockers with the aluminium bridge use a different length to the old ball-pivot rockers. If you use studmount rockers on a head that didn't originally have them though you'll also need guideplates.


Title: Re: 186 vs 202 differences
Post by: FCRB26 on September 22, 2010, 07:17:05 PM
I have a set of stamps i have used a few times and have never had a problem surely no one really cares about a re stamped block if you do it right and destroy the old block its a 30 plus year old engine?



Title: Re: 186 vs 202 differences
Post by: EffCee on September 23, 2010, 01:10:16 AM
Thanks all for your replies, much appreciated

Keith