balanced and lightened crank

[bob the builder]

hi , I am building a high compression engine and was thinking about getting the crank balanced and lightened.
can anyone recommend somewhere in the northwest that will do it and roughly how much it costs.
many thanks rob

 

[bloke]

I'd just go for a billet if you want an absolute screamer.

 

[bob the builder]

thanks for the reply,not got that sort of money really. I was just interested in the cost to see if it was an option.
cheers

 

[bozothenutter]

https://vibrationfree.co.uk

 

[Chambers_RS]

Well worth doing, send everything that bolts to the crank. Pulley, clutch flywheel.

 

[NorthloopCup]

All depends on the crank you’re using. If it’s the standard ph2 172 item, I wouldn’t waste your money. They’re s**t and flex far too much. Only cranks worth bothering with are the ph1 crank and the 197 crank. Anything else is better off being used as a door stop.

 

[Sigmamark]

Balance yes, but lightening the crank is a recipe for disaster as you could end up releasing all sorts of manufacturing stresses. As mentioned above, bolt the flywheel to the crank and the clutch cover to the flywheel and then get it balanced. I was absolutely gobsmacked at the amount of material removed from my clutch cover to get that balanced.

 

[bob the builder]

thanks for all the help.
cheers rob

 

[bloke]

All depends on the crank you’re using. If it’s the standard ph2 172 item, I wouldn’t waste your money. They’re s**t and flex far too much. Only cranks worth bothering with are the ph1 crank and the 197 crank. Anything else is better off being used as a door stop.

the oil pump isn't prejudiced though, it will kill any of the cranks ?

 

[Kev@KAM]

Balancing the pistons, rods and crank etc can help on the harmonics and allow more sustained high revs. You can reduce the mass from the flywheel and clutch if you really want to save a lot of weight. Moving to a small race clutch and flywheel probably saves 5 kg or so vs standard.
No change out of £1500 there though

 

[bloke]

Stick a lightweight crank pulley on, the polish guy who makes them says it will turn your car into a race car and won't do the crank any harm at all!!!°°

 

[JamesBryan]

Stick a lightweight crank pulley on, the polish guy who makes them says it will turn your car into a race car and won't do the crank any harm at all!!!°°

I'm sure that's the guy who i questioned about those pulleys and how they have a lack of vibration dampening could cause damage to the crank.

He said i don't know what i'm talking about, they're completely fine ?

 

[Kev@KAM]

Stick a lightweight crank pulley on, the polish guy who makes them says it will turn your car into a race car and won't do the crank any harm at all!!!°°

Its an interesting one. Somewhat unrelated but this was popular with my car - Toyota AE86 - one of the tuners ditched the full solid setups for ruberised again stating they were more trouble than they were worth.

 

[Kev@KAM]

But on the flipside. Modern cars are internally balanced so these are more to do with noise and vibration. Helping the car be more refined. With our Renaults I dont think theres been any long term assessement of removing it but its probably not a big deal..probably. Not a massive gain either

 

[bloke]

afik they are there for the pulses from the combustion stroke? the differences he claims are absurd as well yet nothing on the dyno to show the tiny tiny difference they do meke though.

 

[Kev@KAM]

Ohh like PTFE gaskets. I've been asked to sell them but I can't find any data they make any real world difference to offset the extra trouble of sealing them

 

[GrahamS]

torque developments balance rotating assemblies

 

[bloke]

we're looking to buy a shed to use as a test/development car and one of the plans is to run it without inlet gaskets, most people think it's impossible to do. funny though as when i said about building a 125 2 stroke up without a headgasket i got laughed at...until it ran ?

 

[Dr HMS Derv Destroyer]

we're looking to buy a shed to use as a test/development car and one of the plans is to run it without inlet gaskets, most people think it's impossible to do. funny though as when i said about building a 125 2 stroke up without a headgasket i got laughed at...until it ran ?

It'll work if both mating faces are bang on machined.

 

[gnome]

I would recommend these guys https://www.head-shop-uk.co.uk/ Warrington based, did mine about four years ago, mines only ever been thrashed around a track and is still going strong, dyno run once a year proves its not lost many horses over the years

 

[Nikidani]

[QUOTE = "NorthloopCup, post: 11691357, membro: 61663"] Tutto dipende dalla manovella che stai utilizzando. Se si tratta dell'articolo ph2 172 standard, non sprecherei i tuoi soldi. Sono s ** t e flettono troppo. Solo le pedivelle che vale la pena di preoccuparsi sono la manovella ph1 e la manovella 197. Qualunque altra cosa è meglio che venga usata come fermata della porta. [/ QUOTE]
PH1
PH2
197

That`s all right?

 

[NorthloopCup]

[QUOTE = "NorthloopCup, post: 11691357, membro: 61663"] Tutto dipende dalla manovella che stai utilizzando. Se si tratta dell'articolo ph2 172 standard, non sprecherei i tuoi soldi. Sono s ** t e flettono troppo. Solo le pedivelle che vale la pena di preoccuparsi sono la manovella ph1 e la manovella 197. Qualunque altra cosa è meglio che venga usata come fermata della porta. [/ QUOTE]
PH1
PH2
197

That`s all right?

Yeah that’s it mate. You’ve missed out the ph2 182 crank though as that’s different again, but equally as shite as the ph2 172 item.

 

[Nikidani]

[QUOTE = "NorthloopCup, post: 11693835, membro: 61663"] Sì, questo è il mio compagno. Hai perso la pedivella di ph2 182 anche se è diverso, ma altrettanto shite quanto l'articolo ph2 172. [/ QUOTE]
You have one image for my album?

 

[NorthloopCup]

[QUOTE = "NorthloopCup, post: 11693835, membro: 61663"] Sì, questo è il mio compagno. Hai perso la pedivella di ph2 182 anche se è diverso, ma altrettanto shite quanto l'articolo ph2 172. [/ QUOTE]
You have one image for my album?

No mate afraid not.

 

[Nikidani]

No mate afraid not.

Thanks NorthloopCup!

 

[bozothenutter]

Ohh like PTFE gaskets. I've been asked to sell them but I can't find any data they make any real world difference to offset the extra trouble of sealing them

Lol....wouldn't the heat just go trough the bolts?
And most of the heat is probably from radiation, not conduction. Be better off shielding/c oiating or some such.....

 

[Kev@KAM]

Lol....wouldn't the heat just go trough the bolts?
And most of the heat is probably from radiation, not conduction. Be better off shielding/c oiating or some such.....

You would certainly get conduction through the bolts. I've seen some on an old supertouring car with a PTFE gasket and a fancy O-ring seal setup but I'm guessing gas speed is high enough that its never been a worthwhile pursuit for main stream parts as the gas barely has time to absorb heat as it passes through convection.
As you can cool the air with fuel the issue is even more slight.

Which leads to your other point. Convection through air to another object is relatively inefficient so if you have a cool airflow through the enginebay other parts are unlikely to heat significantly via that method. It will be more through conduction.