waynefrst235

Hi folks, in need of some advice if possible.

Having had no.4 shell spin on a Cossie engine I sent it off to be checked and rebuilt. They found the crank to still be on standard grind but now has a 17thou bend from the shell going.

I then sourced a second hand crank on a 0.5 grind that I was informed was ready to go however once the engine builder measured it it appears no.4 on that one too is fooked and would need a grind to 0.75, but this crank is straight and always has been.

Has anyone had a crank straightened and how has the car been with it?

My options now are:
1) Straighten the 0.25 grind the std original crank
2) 0.75 grind the 2nd hand one
3) Chuck a gallon of V Power and a match at the car and torch the fecking thing!!

Cheers in advance for any advice/opinions

gingerturbo

iTrader: (2)

I'd personally go with option 2 as its a lot safer to get oversized bearings than have the crank straightend,

bigchez

how much power you looking to run dude? Not sure I'd want to be risking an expensive big hp engine on a bodged crank

waynefrst235

Im not chasing big power, it will be running stage 3 on a t34.48 with no plans to start chasing numbers

saph4be

Would think crank would be fine at that power on a .75 grind

stevieturbo

Get a second opinion on the crank ?

I'd really struggle to believe a Cossie crank would bend

waynefrst235

I've had two machine shops check it and have seen them test it for myself.

They run the gauge round the journals and each one from 1-4 is showing a greater reading than the last so it does have a bend, as said its about 19thou

stevieturbo

Wow.

It must take some effort to do that, and even more for them to be able to straighten it.

Ive seen Subaru cranks bend, although their webbing between the journals is pretty thin. Although even that is rare

waynefrst235

It barely done 300 yards from when the noise was heard til it was stopped

I've been told its when the shell spins it locks and the crank bends/twists as it frees off

Shit happens I guess

CZWRTH NZ

My brother built his VR-4 motor (4g63t) evo etc round a crank that the engine recon shop straightened for him. running approx 320 hp at the wheels does 12.5 quarter miles and when the front axels are out enters most of the local burnout comps. So far engine has performed faultlessly, have they straightened any in the past?
(search you tube VR4 rwd Levin or Masterton, if you wana see an old VR do so sum burnouts its the yellow one, from NZ lol)

Turbo Zetec

iTrader: (1)

should be fine once straightened, as long as it's done properly.

waynefrst235

Yeah they have done cranks in the past but usually they find the bend in the middle which is easier to sort. Mine is bent towards one end

jamie's

as i mentioned to you on facebook, TM Smiths in coatbridge straightened mine 2 years ago, its been running over 400bhp since and has been fine
but i cant remember where mine was bent, might have been the middle, but it was out as it had run no.4 big end shell thru to the copper so i assumed it was there but not sure

AndyR1

iTrader: (1)

ive had one straightened before and worked fine for 10000 miles running 380 bhp still have the moter but its my spare one now

waynefrst235

Cheers folks, seems a split opinion lol

I have left both cranks with the engine builder and said I shall phone them Monday with a decision