29 replies to this topic

[bluemini1979]

Hi
Im building a 1293 engine which I am supercharging using a eaton m45 and planning on converting it to a blow through design. what crankshaft is recommended when using a supercharger? do I need a tuftrided metro/era turbo cam6581 crankshaft or can standard crankshafts be used? or what would other supercharged users use in there builds?
Thanks David

Edited by bluemini1979, 13 November 2014 - 09:41 PM.

[MIGLIACARS]

there are only three standard 1275 cranks apart from the en40 b cranks

 

 

1505

6581

6232

 

 

there is very little difference between them all.

 

my fave is the mpi 6232 as its much prettier due to the balancing the factory did

 

saying that med like the 1505 crank as a exchanged!!!

 

all were heat treated as standard tufrided 

 

despite what some may say the standard cranks are excellent if the journeys are good and there fitted correctly.

 

after years in high competition circuit racing motorsport i now use a standard crank. Ive had no issues at all   , touch wood.

 

its a standard spi crank which was balanced    3 rd season now!!

my racer is 167 hp at the wheels   supercharged.

 a very quick car

 

 

a pal of mine has a n/a 8 port mini very quick car, he runs a arrow stroked crank, at  £ 1800 each he has snapped three this season.   his does 110 at the wheels.     

he and his stupid engine builder ridiculed us for years using a standard crank.

 

 

make your own mind up.

Edited by MIGLIACARS, 15 November 2014 - 09:12 PM.

[Gr4h4m]

I ran a standard crank in my 998 for a good few years. Balance and hardening and taking some weight off like wedging will help it spin up. Making the engine smoother and easier to rev.

[Tupers]

I've got an 84.3MM stroke, wedged, x-drilled and Ni-Temped 12G1505 crank from MED for my supercharged engine. 

 

 

A hardened and balanced crank should be more than up to the job in most road cars. 

[MIGLIACARS]

I've got an 84.3MM stroke, wedged, x-drilled and Ni-Temped 12G1505 crank from MED for my supercharged engine. 

 

 

A hardened and balanced crank should be more than up to the job in most road cars. 

oops i made a mistake in my earlier post,   its not standard  it is cross drilled.

 

all the factory cracks are hardened

[OzOAP]

 
saying that med like the 1505 crank as a exchanged!!!

Thats because a 1505 doesn't have radiused fillets on the journals so they can be off-set ground for 84 stroke.

[HUBBA.HUBBA]

I would say standard crack is fine. Just make sure the whole assembly is balanced. Mines off a 1275 gt and 130hp at the fly, works fine.

[wayne miller]

This is what I'll be using in my supercharged 1380 twinky 

 

 

 

 

[Tupers]

I hope you're getting it checked for straightness.

[MIGLIACARS]

lots of meat taken off that pal.

 

brian slark isnt it.

 

 

did u have it specially done!!!!!!!

[69k1100]

http://www.shengineering.co.uk/sh/

[fastcarl]

 

I've got an 84.3MM stroke, wedged, x-drilled and Ni-Temped 12G1505 crank from MED for my supercharged engine. 

 

 

A hardened and balanced crank should be more than up to the job in most road cars. 

oops i made a mistake in my earlier post,   its not standard  it is cross drilled.

 

all the factory cracks are hardened

 

 no they are not ,  the only hardened standard crank I  have come across are the turbo ones,

 

 

carl

[fastcarl]

This is what I'll be using in my supercharged 1380 twinky 

 

 

 

 

is that tail  just stained or is it  marked up with fretting

 

 

carl

[fwdracer]

This is what I'll be using in my supercharged 1380 twinky 

 

 

 

 

 That will break. I had a SH crank **** itself after 6 hours running in my Mini7 - 8200 rev ceiling. Good luck with usage in a boosted engine.

Edited by fwdracer, 07 December 2014 - 10:13 PM.

[MIGLIACARS]

Boosted engines dont normally rev there t*ts off. so a highly modded crank isnt called for, If the car is for road use then I dought you will see any gains on a crank like that.

 

If the car was an all out racer then any gains are beneficial and that is why there  lightened to the extreme .Dont forget as most do that all out race parts are not the best for fast road use were reliability is crucial.