Knife-edged crank
#1
08-08-2007, 12:36 AM
Knife-edged crank
I did a search and couldnt find any explanation as to what exactly this is... i know it has something to do with removing the balance shafts and relieving rotating mass... but im not exactly sure as to what it is or means
#2
08-08-2007, 01:59 AM
RE: Knife-edged crank
it has nothing to do with the balance shafts, what a knife edged crank is - when you sharpen the egde of the counterbalance to a point like an axe. not always that sharp, but that is just to help cut down windage and free up power, in a sense it makes a crank more aerodynamic and helps keep oil off it.
heres a knife cut crank Vs a stock crank
of course it takes away weight but then you have to add weight back to it to balance it normally.
[IMG]local://upfiles/10240/EC0B7819F1A443C7B8BBB1BFBCE7B62F.jpg[/IMG]
[IMG]local://upfiles/10240/120C19A1931143C791B91E53FCE595F8.jpg[/IMG]
heres a knife cut crank Vs a stock crank
of course it takes away weight but then you have to add weight back to it to balance it normally.
[IMG]local://upfiles/10240/EC0B7819F1A443C7B8BBB1BFBCE7B62F.jpg[/IMG]
[IMG]local://upfiles/10240/120C19A1931143C791B91E53FCE595F8.jpg[/IMG]
#4
08-08-2007, 08:11 AM
RE: Knife-edged crank
dont people remove the balance shafts though? i thought removing the balance shafts would totally screw up the engine... how do you compensate for not having them??
also, if you put a lightened crank in you block, can you get that knifeedged? or no because it is a lightened crank and machining metal off of it will ruin its structural ridgitity?
also, if you put a lightened crank in you block, can you get that knifeedged? or no because it is a lightened crank and machining metal off of it will ruin its structural ridgitity?
#5
08-08-2007, 08:44 AM
RE: Knife-edged crank
if you get a knife edged or lightened crank (or both if it's possible but i think it may be a bit over kill.... could just get a crankscraper) you can remove the balance shaft because you willneed to get it balanced anyways for the new weight/balance of the crank.
#6
08-09-2007, 12:46 AM
RE: Knife-edged crank
again the balance shafts are there to counter the natural vibration a 4 cylinder makes, a shaft shaking around isnt gonna make a damn bit of difference holding the crank and rods together. its there for your smooth ride, thats it. its comfort bull****
you can get rid of the balance shaft without balancing the crank / rods assembly
you can get rid of the balance shaft without balancing the crank / rods assembly
#7
08-09-2007, 03:20 AM
RE: Knife-edged crank
ORIGINAL: RCJr9186
if you get a knife edged or lightened crank (or both if it's possible but i think it may be a bit over kill.... could just get a crankscraper) you can remove the balance shaft because you willneed to get it balanced anyways for the new weight/balance of the crank.
if you get a knife edged or lightened crank (or both if it's possible but i think it may be a bit over kill.... could just get a crankscraper) you can remove the balance shaft because you willneed to get it balanced anyways for the new weight/balance of the crank.
Original poster: Taboo
Only immature morons with an IQ of an ice cube resort to name-calling once they run out of arguments and don't have the appropriate knowledge to continue the discussion in some sort of intelligent manner. It never fails...
Quote:[/align] Originally posted by n2o4fun
If you are ****ing stupid enough to think oil in the pan doesn't reach a crank spinning right above it you should eat a bullet and save us from your bull****.
[/align]
Let me tell you a little secret about our engines. The oil doesn't reach the crank even with the engine not running. Once you start the engine the oil pump delivers 10 cubic cm per revolution - which means the oil level in the oil pan goes even lower once it's supplied to the oil pump, crank and rod bearings, the head, lifters, turbo, etc. The crank does not spin "right above" the oil level. In fact, it does not come even close to it since the crank is located higher in the 4G63 block than in your typical Chevy 350.
Quote:[/align] Originally posted by n2o4fun
The location of the oil drain doesn't matter in this case you stupid ****. Oil still hits the crank and sticks like, well,like oil is supposed too. [/align]
Here's a proof of your non-existent knowledge of the 4G63 turbo engine since you had absolutely no clue what I was talking about when I mentioned the outlet of the turbo oil return line. It's not a drain plug
. The outlet of the turbo oil return line must be located above the oil level in the oil pan in order to work. Anyone with at least some amount of common sense knows that. Take turbo 4G63 oil pan and measure the distance from its lip to the bottom of the oil return hole. Then measure the distance from the oil pan mating surface of the block to the bottom edge of the counterweights of the crank while the engine is in TDC.
You don't even have an idea where the main oil return passages are located in the 4G63 block. FYI, the oil return passage on the exhaust side is located directly above the counterweight of the crank - and above the scraper.
Now the best part I saved for the last...
If you look at the picture of the 4G63 turbo engine I posted, you may notice something attached to the main oil gallery - above the crank on the exhaust side of the block. Yes, the little things are called oil squirters. What do you think they do?
Simply said, the crank scraper does absolutely nothing on our engines for the resons stated above. The crank is constantly coated with oil from the oil squirters and oil return passages in the block that are both located above the crank scraper, not with the oil from the oil pan.
Quote:[/align] Originally posted by n2o4fun
Have I personally seen oil in an oil pan at 7500 rpm, yes I have smartass. Try a pan with a plastic side and a 500" pro stock motor there Chesty. Kim Barr racing in Garland Texas would be the place. [/align]
Was it our 4G63 turbo engine or are you just so ignorant to think that all engines are created equal and some compensation for ****ty design of old Chevy engines can be applied to everything?
Someone said the crank scraper increases horsepower by 5%. Here's a challenge for you:
Take 300HP DSM with 4G63 engine, strap it on a dyno and record an average of three pulls. Install the magic crank scraper within two hours of the pulls, use the same oil you just drained from the oil pan (= no new oil) and record the average of the next three runs on the same dyno. If you make 5% HP more (= 15HP on 300HP car) without any other changes, I'll pay you $1000. Hell, I'll pay you $1000 even if you make just 2% (6HP) more.
Needless to say it's not going to happen since running one's mouth is much easier than coming up with some actual proof to back up the unsupported claims.
The moral to this story: Not everything designed to compensate for lousy design of archaic V8 engines can be adapted to our blocks with the same results. Expecting the same results is nothing but naive and foolish.
Oh, BTW, n2o4fun, since you're not able to communicate in intelligent manner without childish insults and name-calling, you're banned. Go back to your AOL chatroom.
Only immature morons with an IQ of an ice cube resort to name-calling once they run out of arguments and don't have the appropriate knowledge to continue the discussion in some sort of intelligent manner. It never fails...
Quote:[/align] Originally posted by n2o4fun
If you are ****ing stupid enough to think oil in the pan doesn't reach a crank spinning right above it you should eat a bullet and save us from your bull****.
[/align]
Let me tell you a little secret about our engines. The oil doesn't reach the crank even with the engine not running. Once you start the engine the oil pump delivers 10 cubic cm per revolution - which means the oil level in the oil pan goes even lower once it's supplied to the oil pump, crank and rod bearings, the head, lifters, turbo, etc. The crank does not spin "right above" the oil level. In fact, it does not come even close to it since the crank is located higher in the 4G63 block than in your typical Chevy 350.
Quote:[/align] Originally posted by n2o4fun
The location of the oil drain doesn't matter in this case you stupid ****. Oil still hits the crank and sticks like, well,like oil is supposed too. [/align]
Here's a proof of your non-existent knowledge of the 4G63 turbo engine since you had absolutely no clue what I was talking about when I mentioned the outlet of the turbo oil return line. It's not a drain plug
. The outlet of the turbo oil return line must be located above the oil level in the oil pan in order to work. Anyone with at least some amount of common sense knows that. Take turbo 4G63 oil pan and measure the distance from its lip to the bottom of the oil return hole. Then measure the distance from the oil pan mating surface of the block to the bottom edge of the counterweights of the crank while the engine is in TDC.You don't even have an idea where the main oil return passages are located in the 4G63 block. FYI, the oil return passage on the exhaust side is located directly above the counterweight of the crank - and above the scraper.
Now the best part I saved for the last...
If you look at the picture of the 4G63 turbo engine I posted, you may notice something attached to the main oil gallery - above the crank on the exhaust side of the block. Yes, the little things are called oil squirters. What do you think they do?
Simply said, the crank scraper does absolutely nothing on our engines for the resons stated above. The crank is constantly coated with oil from the oil squirters and oil return passages in the block that are both located above the crank scraper, not with the oil from the oil pan.
Quote:[/align] Originally posted by n2o4fun
Have I personally seen oil in an oil pan at 7500 rpm, yes I have smartass. Try a pan with a plastic side and a 500" pro stock motor there Chesty. Kim Barr racing in Garland Texas would be the place. [/align]
Was it our 4G63 turbo engine or are you just so ignorant to think that all engines are created equal and some compensation for ****ty design of old Chevy engines can be applied to everything?
Someone said the crank scraper increases horsepower by 5%. Here's a challenge for you:
Take 300HP DSM with 4G63 engine, strap it on a dyno and record an average of three pulls. Install the magic crank scraper within two hours of the pulls, use the same oil you just drained from the oil pan (= no new oil) and record the average of the next three runs on the same dyno. If you make 5% HP more (= 15HP on 300HP car) without any other changes, I'll pay you $1000. Hell, I'll pay you $1000 even if you make just 2% (6HP) more.
Needless to say it's not going to happen since running one's mouth is much easier than coming up with some actual proof to back up the unsupported claims.
The moral to this story: Not everything designed to compensate for lousy design of archaic V8 engines can be adapted to our blocks with the same results. Expecting the same results is nothing but naive and foolish.
Oh, BTW, n2o4fun, since you're not able to communicate in intelligent manner without childish insults and name-calling, you're banned. Go back to your AOL chatroom.
#9
08-09-2007, 07:52 AM
RE: Knife-edged crank
I'm new to the rice rocket scene, but I do know about V8's. The V8 crank counterweights splash through the oil while turning. This is resistance and kicks some of the oil out of the pan. The first cure is a deeper oil pan(cheaper), which also keeps more oil at the pump pick up during launch, windage trays, baffles, & crank scrapers $$,and knife edging the crank, $$$$$.
Also consider the new light weight rods and pistons need to be compensated at the crank.
When balancing, the cheap method is to drill out holes in the crank. The$$ method is knife edging.
Not sure about how these four bangers work yet so I have know idea on the benefits of anything other than the fact that anything lighter is less weight to move. Less weight to move is faster and more responsive.
Also consider the new light weight rods and pistons need to be compensated at the crank.
When balancing, the cheap method is to drill out holes in the crank. The$$ method is knife edging.
Not sure about how these four bangers work yet so I have know idea on the benefits of anything other than the fact that anything lighter is less weight to move. Less weight to move is faster and more responsive.
#10
08-09-2007, 08:01 AM
RE: Knife-edged crank
wow silver... no way i'm reading all of that lol but i did read the small part. now i am confused and mabey it's b/c i have the I.Q. of an ice cube but... the crank does splash the oil in our oilpans doesn't it? isn't that how the crank/bearings stay lubricated? i feel like a freakin newb this week man... not cool