Customcreations
Tuner
Thought I'd let others know because this is something I would normally not check. I bet this is the case on many different ENGINE brands
(Many crank shafts are not as accurately finished of as people may think or ASSUME) Sure plenty of attention goes into machining the crank so that the Rods fit well and the Crank itself is fitting good in the block BUT
to say, Where the F/W marries up to the crank could be a shotty finish on the CRANK and will give you a Wobbly Flywheel.
I can only speak for the EcoTec engine at the moment as this is how I found it out by chance.
I am doing a VS Commodore Auto trans to Manual conversion,
in this process I decided to modify a 6 Bolt F/W (FlyWheel) by making and
adaptor BOSS/plate so it fits on the 8 bolt Ecotec engine.
2 reasons for doing this,
1:: The 8 bolt F/W is quite expensive and so it will allow me to sell the 8 Bolt F/W and recoupe some costs for my conversion.(IF anyone's interested:bigsmile: $$$ I can even lighten the 8 bolt F/W if requested)
(second hand and CRUSTY they sell for $250AUD easily) Mine is NOT rusty though and has also had a light surfacing by previous owner which is quite visible (he didn't have it in long before there was a flood which flooded his engine so he gave up and sold the lot sadly for me I only got the gearbox and 8 bolt F/W)
2:: I weighed the 2 F/W's as I noticed with picking them up and comparing that the 6 BOLT F/W was very noticably lighter than the 8 BOLT F/W.
The 8 Bolt F/W weighed in at around 10.9Kg
(VR-VS supposedly but any 8 bolt holden V6 Crank is going to take this same F/W in my opinion)
The 6 BOLT F/W weighs in at 9.2Kg.
That included the Adaptor BOSS/plate I made for it which was made from a strong and solid Cast Iron.
That's a massive weight reduction of1.7Kg
bigsmile:I think I've definately caught this weight reduction bug Old-Git:bigsmile
giving me a very cost effective Home Modified "Performance" Flywheel.
At first I thought it must have been the adaptor plate that had this2MM wobble so I put the 8 Bolt F/W on to double check it and it still had the same and at the same point (or side). I had even wasted some time double checking the Adaptor that it was good.
Then last night I was thinking obout putting a micrometer on to the Crankshaft (to where the flywheel would bolt up) and check it that way.
Found that the Crankshaft machining was below average and was the cause of the WONKY F/W. 0.5mm WONKY factor on the Crank shaft.
I didn't want to take the crank out:sad2: so I got a file and over 6 hrs have been (VERY VERY carfully and accurately, also using the micrometer to confirm during and at final finish) filing down the high side on the Crankshaft.
I've got the 2MM WOBBLE at the O/D (outer Diameter) of the F/W
surface down to 1mm so far.
(NOT at the outer END where the ring gear is)
(I want to make sure that IF I ever decide to or have to put a different F/W on I can do it without having the wobbles again, otherwise I would have filed the F/W down instead of the crankshaft)
1mm at the Flywheel is 0.2mm now at the Crankshaft.
By this stage my body was starting to get rather annoyed at me for sitting under the car with a file in my hand. (I am 40)
Will have another go at it in the morning but I'll try using some Emery paper around the file to see if that will work a bit quicker.
This innacuracy on the crankshaft could be due to the fact the engine has seen around 250,000Km. So could be due to the stresses. But if it was 0.5mm and due to stress, you would think the crank would be very twisted and ENGINE would not run very happy. This engine does run smooth as.
(HEY maybe GM added the Balance shaft to their engines because of their shotty finishing work
)
(Many crank shafts are not as accurately finished of as people may think or ASSUME) Sure plenty of attention goes into machining the crank so that the Rods fit well and the Crank itself is fitting good in the block BUT
to say, Where the F/W marries up to the crank could be a shotty finish on the CRANK and will give you a Wobbly Flywheel.I can only speak for the EcoTec engine at the moment as this is how I found it out by chance.
I am doing a VS Commodore Auto trans to Manual conversion,
in this process I decided to modify a 6 Bolt F/W (FlyWheel) by making and
adaptor BOSS/plate so it fits on the 8 bolt Ecotec engine.
2 reasons for doing this,
1:: The 8 bolt F/W is quite expensive and so it will allow me to sell the 8 Bolt F/W and recoupe some costs for my conversion.(IF anyone's interested:bigsmile: $$$ I can even lighten the 8 bolt F/W if requested)
(second hand and CRUSTY they sell for $250AUD easily) Mine is NOT rusty though and has also had a light surfacing by previous owner which is quite visible (he didn't have it in long before there was a flood which flooded his engine so he gave up and sold the lot sadly for me I only got the gearbox and 8 bolt F/W)
2:: I weighed the 2 F/W's as I noticed with picking them up and comparing that the 6 BOLT F/W was very noticably lighter than the 8 BOLT F/W.
The 8 Bolt F/W weighed in at around 10.9Kg
(VR-VS supposedly but any 8 bolt holden V6 Crank is going to take this same F/W in my opinion)
The 6 BOLT F/W weighs in at 9.2Kg.
That included the Adaptor BOSS/plate I made for it which was made from a strong and solid Cast Iron.
That's a massive weight reduction of
1.7Kg bigsmile:I think I've definately caught this weight reduction bug Old-Git:bigsmilegiving me a very cost effective Home Modified "Performance" Flywheel.
At first I thought it must have been the adaptor plate that had this
2MM wobble so I put the 8 Bolt F/W on to double check it and it still had the same and at the same point (or side). I had even wasted some time double checking the Adaptor that it was good.Then last night I was thinking obout putting a micrometer on to the Crankshaft (to where the flywheel would bolt up) and check it that way.
Found that the Crankshaft machining was below average and was the cause of the WONKY F/W. 0.5mm WONKY factor
on the Crank shaft.I didn't want to take the crank out:sad2: so I got a file and over 6 hrs have been (VERY VERY carfully and accurately, also using the micrometer to confirm during and at final finish) filing down the high side on the Crankshaft.
I've got the 2MM WOBBLE at the O/D (outer Diameter) of the F/W
surface down to 1mm so far.
(NOT at the outer END where the ring gear is)
(I want to make sure that IF I ever decide to or have to put a different F/W on I can do it without having the wobbles again, otherwise I would have filed the F/W down instead of the crankshaft)
1mm at the Flywheel is 0.2mm now at the Crankshaft.
By this stage my body was starting to get rather annoyed at me for sitting under the car with a file in my hand. (I am 40)
Will have another go at it in the morning but I'll try using some Emery paper around the file to see if that will work a bit quicker.
This innacuracy on the crankshaft could be due to the fact the engine has seen around 250,000Km. So could be due to the stresses. But if it was 0.5mm and due to stress, you would think the crank would be very twisted and ENGINE would not run very happy. This engine does run smooth as.
(HEY maybe GM added the Balance shaft to their engines because of their shotty finishing work
)
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