
202 steel cranks
#1
Posted 07 November 2006 - 07:47 PM
Cheers
Les
#2
Posted 07 November 2006 - 08:55 PM
#3
Posted 07 November 2006 - 09:10 PM
Yes, that's correct. There is no such item as a forged steel 202 crank. The big myth is that cast cranks are weak. That was probably true in the 50s when the technology to cast a crank out of nodular iron wasn't around. Virtually all Holden motors since 1966 have had cast cranks, without drama.
When the late P. Brock won Bathurst in 1972 in the LJ GTR XU-1 he did it using a cast crank.
I've been playing with cars for over 40 years (over 30 in my own business) & I still have not seen a Holden Red 6 crank fail. When building Holden 6 cylinders, stick with the factory bits you have & forget the forged steel crank myth.
Dr Terry.
#4
Posted 07 November 2006 - 09:38 PM
Only in HP block, 179's in EH's.Sorry...I'm pretty sure they are all cast...only steel cranks were 3.00 inch stroke red motors before 1968..ie no 202
That i'm aware of!
Edited by LX2DR, 07 November 2006 - 09:39 PM.
#5
Posted 07 November 2006 - 09:57 PM
From whats been said by Dr Terry and myself...he said 1966..I said 1968...that means you should be able to get a 186 out of a HG and it will have a cast crank..but i haven't seen one..but then again I pretty much only muck around inside 179's and 149's and the odd 202. I am pretty sure the 186S used a steel crank and it stayed in production until the HQ came along.
#6
Posted 07 November 2006 - 10:19 PM
#7
Posted 08 November 2006 - 06:57 PM
Another Queston, What do you gain if anything from putting a 202 crank into a 186 block, As far as I can see all it does is turn the 186 into a 202 as the bore size is the same so all you are changing is the stroke.
Les
#8
_CHOPPER_
Posted 08 November 2006 - 07:28 PM
#9
Posted 08 November 2006 - 08:07 PM
#10
Posted 08 November 2006 - 08:22 PM
#11
_dave720gtr_
Posted 08 November 2006 - 08:48 PM
#12
Posted 08 November 2006 - 08:53 PM
#13
_CHOPPER_
Posted 08 November 2006 - 09:20 PM
#14
Posted 09 November 2006 - 11:23 PM
this was before black cranks found there way into the rebuild. dont know if it solved it
would it be best to start with the black motor?
#15
_dave720gtr_
Posted 10 November 2006 - 12:07 AM
that fixed any flex that may of or not happend at 20psi +7000+rpm

#16
Posted 10 November 2006 - 05:17 AM
#17
Posted 12 November 2006 - 09:52 AM
the would start having problems with flywheel and blocks at 7000+prm. I lost near sot a Y/T flywheel with 7/16 12point ar . Spat all the heads of the bolts off, Gearbox was holding it in there. Was spinning pass 8500+ rpm.black blue any will do! i used a low k black engine 3.3 just got arp studs and 360 mains guirdle
that fixed any flex that may of or not happend at 20psi +7000+rpm
If you go to Crankshaft rebuilder, they have blue cranks for about $1500, you won't break one of there cranks.
#18
_dave720gtr_
Posted 12 November 2006 - 11:55 AM
dowwled to the crank standed on black cranks, ARP bolts will be used to.
i have never seen a holden 6 break a crank in harlf .an less it was ground out of phase ,
Another point. flex in the crank is not up and down. its a twisting flex
that effects red cranks a hi rpm. blue black dont twist as much but are heavier.
but u can remove lots of meat from the counter weights down to a knife edge.
#19
_82911_
Posted 12 November 2006 - 01:01 PM

Now that's some serious flex!
This combo makes better than 600HP measured....So is at 3HP/cube, it doesn't break cranks so you are fine in that regard.. But it sure as hell consumes an awfull lot of blocks.......
Cheers greg..
#20
_dave720gtr_
Posted 12 November 2006 - 10:22 PM
must be up round 35psi or more to be eating blocks . my friends been running up to 30,
Turbo intercooled fuel injected ,has never cracked a block but has melted pistons
warped his Y/T alloy head and soften the alloy .had to send it to melbourn to have it re heat treated and straightened. This happened when water pipe fitting blew out
on a full boost run. It over heated istantly and the HQ race piston became ONE with the bore!

#21
_82911_
Posted 13 November 2006 - 07:21 AM
another aside....
we regularly kill blocks in the group N Xu-1's but it is mainly due to harmonic vibration rather than crank flex or combustion pressure.
I think you will find that if you start turning/boosting it hard enough, often enough you will have the odd failure..
Thy usually go along the side about an inch down from the deck on the exhaust side.
BTW: the girdle does appear to help extend the life of the block.
Cheers Greg..
#22
_dave720gtr_
Posted 13 November 2006 - 09:18 AM

I see he sells them heads jacketed or solid with out water passagers
I wounder if his blocks are semi grout filled .
hum i think i will run no more then 20 at the strip and 10./15 on the street.

oh and that F.I.Turbo engine in my friends LC as made over 470hp

Edited by dave720gtr, 13 November 2006 - 09:24 AM.
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