10 replies to this topic

[R.S.P]

Ok time to buy a new crank for my project, spec so far


block bored to 73.5mm honed, centremain fitted and machined for 16v conversion

pistons and rod machined for 16v conversion

ultralite flywheel and backplate

16v head


so cant decide on what spec crank should go for (Dont want to spend money where not required, but dont want it to go bang)

car will be used for going to and from shows, not a track car.

and where would be best tp purchase? ( been looking at MED, but open to sugestions)


Thanks in advance Darren

[Sprocket]

Wedged, bladed, cross drilled and hardened. Make sure you get the whole rotating assembly acurately balanced, do not rely on the balance of the individual components, including the crank!!

Blading the crank may not be totaly nescisary, but at 8500rpm, it should help something

[alexcrosse]

with sprocket. 12G1505 or a cooper s crank, x drilled, balanaced, nitrocarbonised, wedged.

[R.S.P]

Thanks for the replys, so blading

Yes it will be lighter so should spin up quicker,but will it make that much difference?


And would MED be your first choice?


Thanks Darren

Edited by R.S.P, 18 February 2008 - 08:58 AM.

[Guess-Works.com]

no point having a cooper S crank, as you'd then have to change to cooper S rods....

Personally, if it's a daily driver and not raggin the **ts off it, a standard crank should be well up to the job, but I'd get a tuftried and x drilled one for that added longevity of service.

[R.S.P]

Well thanks for the help, answers as i thought.


went for the Reground, Ni – Temp, Wedged & X-drilled

and some vandrvell vp2 big end and main bearings.


Thanks again


Darren

[alexcrosse]

but if you were doin a 16v (dependant on conv) you will probably need cooper s rods.

Getting weight off the crank isnt going to make a huge around of difference, and if you concentrate on weight first time itll be harder to balance if you do more work on it later on.

12G1505 if a nice strong crank, larger big ends than any other crank (sure from my research). Balance, wedge, xdrill and nitrocarbonise and you will be laughing. Its a turbo crank by the way.

[R.S.P]

Thanks Alex, crank ordered now.

All my 16v conversion has been done by specialist components and uses A+ rods and crank.


Which 16v conversion do you have to use S rods on?



Cheers Darren

[Sprocket]

but if you were doin a 16v (dependant on conv) you will probably need cooper s rods.

Getting weight off the crank isnt going to make a huge around of difference, and if you concentrate on weight first time itll be harder to balance if you do more work on it later on.

12G1505 if a nice strong crank, larger big ends than any other crank (sure from my research). Balance, wedge, xdrill and nitrocarbonise and you will be laughing. Its a turbo crank by the way.

CAM6232 A+ crank every time, ( can still get these new for £140) far better than any of the standard A cranks, its going to be hardened anyway. they caurrently support 240bhp At least a center main strap is a must!!, but DO NOT USE THE BOLTS WITH 3 DASH MARKING!!!! source some 6 dash or some Unbrako cap head bolts (Rob Walker Racing) You have been warned.

Cooper S rods, Why? Modified A series rods are good enough and the A+ are not far behind even in standard form. ARP rod bolst are a MUST however!!!!!

Weight off the crank is everything when you are building an 8500rpm engine. Fiar enough you are not going to be constantly reving it to 8500rpm, but it will visit quite often.






The crank you bought is more than up to the job, as i had suggested Just remember the pointers above

[R.S.P]

Cheers sprocket


got ARP rod bolts

will have to have a look at the bolts for the centre main, they were supplied by sc when they done the machining, hope they are the correct ones, or money to spend lol

[R.S.P]

Well checked mine and they are the 3 dash type, is this the place to get the unbraco ones from? http://www.robwalker...o.uk/index.html

Cheers in advance Darren