Knife Edge a GTiR crank

[cmng]

Worth the effort to knife edge the crank

or worth the risk ?

 

[Dee 1]

Worth the effort to knife edge the crank

or worth the risk ?

There`s plenty of people running knife edge cranks on here mate so i`d say a big YEH 8)

 

[skiddusmarkus]

Mine is but I wouldn't like to say whether it's worth it or not.The theory is that it cuts through the oil easier so less drag on it and it revs more easily.
I was told it's not really necessary for a road car.

Has anyone actually had their crank irreperably damaged fromt the knife edging process?

 

[MarkTurbo]

I was told it's not really necessary for a road car.

I remember a big debate about it from when i used to have a renault 5 turbo.

Some people thought it was a bad idea cos instead of going into the oil and splashing it around the engine it just cuts through it.

I dont know how much this would affect the life of the engine :? Its not really an issue on race cars cos they get regular rebuilds.

 

[Anonymous]

according to farndon engineering,who make stroker kits etc for the R,it's only really necessary to knife edge a crank when it's in a race engine.they also said that you'd not see or feel any difference at all in a road car.

dee1-just cause a lot of people have done the same thing does not necessarily mean it's the right thing to do.that can be a very dangerous assumption

 

[Dee 1]

according to farndon engineering,who make stroker kits etc for the R,it's only really necessary to knife edge a crank when it's in a race engine.they also said that you'd not see or feel any difference at all in a road car.

dee1-just cause a lot of people have done the same thing does not necessarily mean it's the right thing to do.that can be a very dangerous assumption

I know what your saying mate but at the end of the day lots of people have been running knife edge cranks for quite a while now and have no problems includeing me so it seems to prove that its not causeing any probs. Surely there are lots of mods that are being done to the R that can only be deemed safe by haveing ago and letting time tell if its works or not. You know T@Error :?:

 

[campbellju]

I jut got my crank balanced as a few people said it would be a waste of money in terms of bang per buck. Can't comment on the reliability though I did hear the comment not for a road car a few times. Whether this is because of cost or reliability I never asked.

Jim

 

[Anonymous]

I know what your saying mate but at the end of the day lots of people have been running knife edge cranks for quite a while now and have no problems includeing me so it seems to prove that its not causeing any probs. Surely there are lots of mods that are being done to the R that can only be deemed safe by haveing ago and letting time tell if its works or not. You know T@Error :?:

point is,there might not be any problems but,going by what the crank manufacturers are saying,there isn't any benefits either :shock:

i'm not saying it is a dangerous or problematic thing to do,it's just a waste of money if there are no tangabile benefits

don't have to tell me about trial & error :lol: it's just that nowadays there aren't that many things that have not already been tried before and i personally think that it's only the really expensive mods that will give any real gains now

 

[Anonymous]

I jut got my crank balanced as a few people said it would be a waste of money in terms of bang per buck. Can't comment on the reliability though I did hear the comment not for a road car a few times. Whether this is because of cost or reliability I never asked.

Jim

lightening and balancing the bottom end will not generate any extra torque or power but it is one of the most worthwhile mods you can do as it maximises the power/torque delivery and also increases,i think,reliability.

getting the bottom end lightened & balanced isn't the same as knife edging the crank

 

[jonee]

r

if your crank is rotating through your oil in your sump then something is seriously amiss :shock:


the only reason that a crank is knife edged is for aerodynamics and to loose rotating mass not to cut through your engine oil.

there is NO power gain through lightening your crankshaft or flywheel.

the engine will only rev up faster due to less rotating mass and in turn there will be less stress on engine components.

cheers jonee

 

[BabyGodzillaGTi-R]

Talking about knife edging i dont understand why some ppl say it's not recommended for a road car as it is quite similiar to running a lightened flywheel.
It allows u to rev much faster but also can be couterproductive as the revs can drop much faster too.
So around town driving situations and driving uphill, i was told the engine cant hold the revs as well as b4.

What say u guys?

As for cmng.......
since u intend to build a 10sec car go ahead man. Hahaha
Long live the Hyper Sunkist Orange JUN Auto Sentra B13.
:twisted: :lol: :lol:

 

[Anonymous]

Talking about knife edging i dont understand why some ppl say it's not recommended for a road car as it is quite similiar to running a lightened flywheel.

you've not understood the thread correctly.it's not that it's no good for a road car,it's that there is no benefit knife edging a crank for a road car.

 

[Fast Guy]

Read this for those that haven't alreay read it before.


Loosing weight is alway a performance gain. (unless you have too much power and you end up with more wheelspin :? )

 

[skiddusmarkus]

Mine revs faster with all the lightening of the rotating mass.It doesn't seem to have a problme with the revs falling off though I've been told it could.It also says it on GT so it muct be true .

 

[skiddusmarkus]

I found this when searching for explanations of knife edging.

Q: What is "knife-edging" a crank?

A: Knife-edging a crank consists of thinning the counterweights to cut parasitic power losses normally encountered when rotating through splashing oil in the oil pan. This reduces rotating mass, allowing for a faster revving, higher rpm engine.

 

[campbellju]

I jut got my crank balanced as a few people said it would be a waste of money in terms of bang per buck. Can't comment on the reliability though I did hear the comment not for a road car a few times. Whether this is because of cost or reliability I never asked.

Jim

lightening and balancing the bottom end will not generate any extra torque or power but it is one of the most worthwhile mods you can do as it maximises the power/torque delivery and also increases,i think,reliability.

getting the bottom end lightened & balanced isn't the same as knife edging the crank

Yep, that post of mine came out completely wrong. Meant to say got thr crank balanced as a must have for reliability/smoothness but was advised by the engine builder that for knife edging my money would be better spent elsewhere.

In short, I agree

 

[Anonymous]

In short, I agree

i'll cherish this as it doesn't happen very often :twisted: