stock turbo crank vs. forged steel

["More Boost"]

when is it time to switch to steel forged crank? how fast will a stock buick turbo crank go with steel main caps? i dont want to spend excess cash that isnt neccassary. please,

 

[opeltwinturbo]

With a stock crank, center caps and a girdle,my GN went 10.60 at 128 just before Otto blew it up (rod knock). Prior to the girdle I was breaking them every 21 passes launching with a transbrake @ #15. Twice was enough. Didn't need Otto for that. How fast do you want to go?

 

["More Boost"]

10.50 would be awsome for me, a guy i know wants $275 for stock turbo crank that needs to be turned .010 i can buy a forged crank for like $400 (ish) i was wondering if i would waste money on forged to do 10.50's money that could go elsewhere, u know?

 

[FastRegalWE2]

10.50 would be awsome for me, a guy i know wants $275 for stock turbo crank that needs to be turned .010 i can buy a forged crank for like $400 (ish) i was wondering if i would waste money on forged to do 10.50's money that could go elsewhere, u know?

275 for a used crank that needs turned, another 75-100 to turn it, thats 325-350, get the forged for another 50 and have the peace of mind. :biggrin:

 

[noahzark]

you can get the forged ones for less than 400 now anyway...320 i think...but you will probably get an internally balanced one so then you need a harmonic balancer another 420...and a flexplate another 200...and then you need it all balanced ...my experience...change one thing then change them all ...because you are already there...noah.

 

[FastRegalWE2]

you can get the forged ones for less than 400 now anyway...320 i think...but you will probably get an internally balanced one so then you need a harmonic balancer another 420...and a flexplate another 200...and then you need it all balanced ...my experience...change one thing then change them all ...because you are already there...noah.

"This crank is internal balance and requires the use of of an internal balance balancer and flexplate OR the stock units must be modified to internal balance specs"

 

[Blown&Injected]

yep, count on another thousand dollars to go internal balance forged.

It Is Not A Drop In!

And then to put the cast rods on that new crank with new forged pistons - that would be the right way

 

[noahzark]

from what i have read the stock balancer is not a balancer but a metal hub...yes it can be modified but i believe most engine builders dont due to the fact of it exploding that and the stock flexplate...so to go to the trouble of putting in a forged crank ...imo you might as well go with a real harmonic balancer and flexplate...im going through the same thing with everything on this engine what started out as a 5k rebuild is now sitting at 10k and still not done...my understanding is if you want to go fast reliably its going to cost money ...so its a can of worms ...dont open it unless you really want to...noah.

 

[TurboCrazy]

Nick Micale has external balance forged cranks for sale.

 

[Clark6]

Nick Micale has external balance forged cranks for sale.

are these drop in or do they need work also?

 

[Clark6]

[

10.50 would be awsome for me, a guy i know wants $275 for stock turbo crank that needs to be turned .010 i can buy a forged crank for like $400 (ish) i was wondering if i would waste money on forged to do 10.50's money that could go elsewhere, u know?

a guy in the for sale section just sold a stock one already turned .10 for $185.

 

[FastRegalWE2]

Chris McDade on this board sells the cranks, stock, ready to go. Many people have bought them from him as well as myself.
If you go with a stock crank that needs turned, gotta make sure, from what Im told, that the machinist doesnt take off too much meat from the sides of the journals.

 

[MSDGN]

I have stock TTA crank in mine...have about 60-70 runs on it in the 10.4-10.6range...motor is girdled and the crank was new(not used) when I put it in...

 

[bison]

From what ive seen the stock rods $hit the bed before the crank in most cases. They will bend with a slight amount of detonation over 600hp. In the absence of detonation the stock crank has gone high 9's reliably with a girdle and h-beam rods. The ultimate is a billet crank, and a set of Oliver rods with JE's or Diamond pistons. The Cat/Eagle forgings and K1's with a girdle and an internal balance hasnt been a problem when balanced and checked for proper machining and has gone sub 9.50's.

 

[TurboCrazy]

Clark6,

They are are Eagle cranks. They were made to be drop-in forged cranks. But, as with all after market parts, they should be checked throughly. Hopefully Nick will chime in with the rest of the story.

 

[Nick Micale]

Clark6,

They are are Eagle cranks. They were made to be drop-in forged cranks. But, as with all after market parts, they should be checked throughly. Hopefully Nick will chime in with the rest of the story.

Key to proper use of ANY aftermarket or factory internal engine part, they MUST be checked for use with all the other parts for compatibility.

This crank, like any replacement crank, will also have to be balanced with the complete rotating assembly.

 

[ChrisCairns]

when is it time to switch to steel forged crank? how fast will a stock buick turbo crank go with steel main caps? i dont want to spend excess cash that isnt neccassary. please,

I had a .010 under stock crank and stock rods, girdled. One and a half years of mid to low tens before a 9.98 @ 136.