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What is the general consenses of the maximum safe RPM for the VE 4 counterweight crank vs the DE 8 counterweight crank?

Is their any evidence to conclude that the 4 counterweight crank is not safe to rev past 8000?
 

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choaderboy2 said:
What is the general consenses of the maximum safe RPM for the VE 4 counterweight crank vs the DE 8 counterweight crank?

Is their any evidence to conclude that the 4 counterweight crank is not safe to rev past 8000?
I don't think a consenses has really been reached. I have not heard of any failures yet from revving to 8k on the 4 cw, but I don't think anyone is revving that high in a road race situation where its seeing that rpm for an extended period of time.
 

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There is no PROVEN FACT at all about that...just lots and lots of speculations...

but many people here are just followers I have seen a hand full of VE's revving to 8,500rpm and 9kish RPMS on 4cw cranks...

the only downside to it its that supposedly you will have bearing wear earlier than a 8cw thats IT!...and we are not talking about 10-15k miles on it so I think its a stupid dilema or just for the people who think their car should last 50k miles or more but cmon the mayority are building VE's to RACE not go shopping...

anyways who am I soon enough there will come someone and say its not safe and make you buy an 8CW lol!!!
 

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choaderboy2 said:
What is the general consenses of the maximum safe RPM for the VE 4 counterweight crank vs the DE 8 counterweight crank?

Is their any evidence to conclude that the 4 counterweight crank is not safe to rev past 8000?
I use to rev my 4 counterweight crank to 9200 rpm and it held up for a year now. The current owner still rev’s it that high and has not failed yet with a lot of abuse. The problem is 4 counterweight crank wear’s out the bearing way faster that 8 counterweight, that’s the only thing I have notice this far. The motor also has UR racing pulley’s which people say promote vibration, while I agree it does us guys up in NYC love to push it to max.If I were to suggest a safe rpm for daily use it would be 8500-8800 rpm’s for 4CW crank with the appropriate springs and camshafts .
 

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Digitek said:
There is no PROVEN FACT at all about that...just lots and lots of speculations...

but many people here are just followers I have seen a hand full of VE's revving to 8,500rpm and 9kish RPMS on 4cw cranks...

the only downside to it its that supposedly you will have bearing wear earlier than a 8cw thats IT!...and we are not talking about 10-15k miles on it so I think its a stupid dilema or just for the people who think their car should last 50k miles or more but cmon the mayority are building VE's to RACE not go shopping...

anyways who am I soon enough there will come someone and say its not safe and make you buy an 8CW lol!!!
Damn you beat me to it.Oh yea we love to rev to 9k+ with 4cw:D
 

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Jah Rastafari
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Well I hate the 4 CWC.

Now the 4 CWC has its advatages. 1) being it is 7 pounds lighter than the 8 CWC, great for faster revs 2) Since there is 4 less counterweights there is some more gain in HP as there is less oil smacking up against the crank.

Here are the facts any high reving 4 piston motor you can find will be fully 8 CW.

Nissans early SR16VEs were 4 CWC, this was done in the first 2 year models, after that Nissan switched back to the 8 CWC. I am sure they saw something they did not like. Yes they are building these motors to last 150,000 plus miles so to them it maters, As for many guys on the forum who might pull down a motor every 25,000 miles to refresh it there might not be a problem.

If you go over on G20.net you will find alot of guys that have the P11 roller rocker motor cars have had a higher rate of engine failure vs the older motors. They alwas die fo rod knock

As for me I will stick with the 8 CWC and have Golden Eagle knife edge my 8 CWC to loose some weight, which should be about 7-8 pounds.

These are my opinions and dont hold them as fact. The only fact is Nissan switching from 4 to 8 CWC on the SR16VEs.
 

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There you have it 4cw crank sucks....Miko for president should I say? LOL na maybe Crank Wizard...

just tripping...thats a real fact...but then again as you said nissan has other focus other than racing more relability than racing...

as for the mayority of this community I find this case more of personal likings since I really doubt someone wants to build a VE for 100k miles + if so I guess your in the wrong forums or atleast should stick to a DE rather than a VE ;)
 

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Jah Rastafari
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Get your wizards straigh buddy

I am " The 4 Eyed Wizard "

 

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Digitek said:
as for the mayority of this community I find this case more of personal likings since I really doubt someone wants to build a VE for 100k miles + if so I guess your in the wrong forums or atleast should stick to a DE rather than a VE ;)
You are completly wrong, many people on this forum build thier VE as a reliable daily driver.
 

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Will said:
You are completly wrong, many people on this forum build thier VE as a reliable daily driver.

Oh ok their going cross america then...cus I don't see whats not realiable of it.

but Im done..relability depends on many other things than a crank but oh well....you are far beyond my knowledge...Your sig fits perfect ;)
 

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Digitek said:
Oh ok their going cross america then...cus I don't see whats not realiable of it.

but Im done..relability depends on many other things than a crank but oh well....you are far beyond my knowledge...Your sig fits perfect ;)
:rolleyes:

So you are telling me that I am wrong, and many people on this forum do not expect to get over 100k miles out of thier VE?

:sigh: I guess im just fooling myslef, huh?

My prior statements do no concearn the actual advantage/disadvantage of 4CW cranks, but your generalizations about the concearns of this community.
 

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The Genesis
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from what ive seen, a lot of guys build ve's for a daily driven car who will see its share of abuse..most of these guys dont have any plans on replacing these motors any time soon or opening the up ever 25k miles to freshen up the internals, etc
 

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The Super Mechanic
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I think the crank is not a problem. I think the issue on the vibration theory is that there is no girdle on the 4 cw crank. the 4 cw crank may shift those caps a little bit at the high rpms. Why not put a girdle on a ve motor. use the de caps and girdle. Have the block align honed and you will never have problems. Knife edging is a waste of time and money. Making the crank with sharper ends on it does not split the oil up like you would think. Many engine builders found that a waste of time. Taking weight off will help in rpm increasing and decreasing. If you go this far you should be doing a dry sump and then there will be no issues. There is lack of oil in the cylinder block(no splatter of oil on the crank). As far as bearings go our oil pumps do not like the high revs. yes the g20 blow bearings because the oil pumps are only good for 6000 rpms. On top of that those yuppies never change the oil on a regular basis.

you want talk about wizzards
I think he is the ultimate
 

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The Super Mechanic
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I had this professionally done on my ZCar. You could spend 300-400 on getting it knife edged and 150 for balancing. I still think it is a waste of money. Many machine shops agree with me. Remember my opinion and im not bashing anyone.
 
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