forge crank?

[97stanger]

within the next weeks I will be buying my forged rotating assembly. I am shooting for 550-600rwhp THROUGH MY BUILT AUTO. Do you guys think I should forge my crank, or could I save some bucks and just get the forged rods/pistons? its just tempting to reuse my crank that has only 48k original miles and looks like this:

 

[duff daddy]

Tim Matherly uses stock crank, but just get a Cobra crank for the money and have some insurance. If your were NA id say dont waste the money

 

[97stanger]

im getting mixed reviews, Mike (sxynerd) said he has two friends, both at 700rwhp with cast cranks for 5 years and never once had a problem. And this car will never ever see more than my 550-600rwhp goal.

 

[duff daddy]

yea, if im giving advise use a forged, if its for me ill use a cast lol

 

[Jrgunn5150]

I don't see any reason not to use the stock crank. It's also lighter than forged.

 

[97stanger]

thats a good point too J.R. As long as I get everything balanced, I dont think I will have any problem just keeping my stock crank

 

[Jrgunn5150]

I also forgot to mention, auto's are waaaay nicer to cranks than manuals, that's why auto Mach's have cast cranks.

 

[NERD]

I understand the "why risk" philosophy and welcome it. As many of you know, there are 2 main factors that affect the crank when it comes to metal fatigue or failure, RPM and Balance. I have never seen a cast crank break under 7k rpm nor have I ever seen a properly balanced engine blow a crank. The few that I have seen (Tocca) had fully built and blown engines with stock HB (Stupid) and were spinning 8k rpm.

My wifes car is keeping the cast crank and I am not worried at all. (My wife would kill me if I risk her car just to save a couple bucks. So since I'm scared of her, You know I have to trust it.)

 

[97stanger]

yeah I have decided I'm just forging my rods/pistons, so I should be able to get this within the next few weeks now

 

[97stanger]

I think I'm definately going to use my stock crank, what do you guys think of a kit like this:

http://www.cushmanmotorsports.com/index.php?main_page=product_info&cPath=11_19_220_28_35&products_id=1702&zenid=037a026b00a853f1cdfe9a780df92772

 

[amy98gt]

ive done builds with both and what i would say is dont skip out on insurance. if your going to the trouble of building it this far go for the forged crank. if something were to happen. that once in a lifetime chance. you blow a gasket, main seal, whatever. loose oil and scar the crank. no worries, its a forged crank, polish it out and your good to go.

go for a kellogg!!!!!

 

[blown98gt]

8 bolt cobra crank.. you'll be able to tell the difference it'll have 2 extra counterweights on the crank.. what i'm using

 

[97stanger]

i talked to 3 race shops, and they 100% talked me into using my stock crank. They even told me that most of their cobra guys that are only in the 500-600rwhp range actually switch to stock cast cranks because they are so much lighter.

 

[97stanger]

plus they said since I am an auto, this is A TON less stress on the crank

 

[Jrgunn5150]

plus they said since I am an auto, this is A TON less stress on the crank

That's what I just told you, lol.

Anyhow, the kit you linked to is good qaulity stuff and will work fine.

 

[duff daddy]

b/d and cast crank

 

[cmher18]

I disagree on the crank man. If your making 600 rwhp through a stalled auto your over 700 at the crank.. I have broke my stock crank on my first build. shifting @ 6700-7000 rpms


But i can do $1200 + shipping without the crank. All Manily stuff

 

[97stanger]

Hey Chris, does your quote include forged rods, ARP2000 bolts, forged pistons with tool steel pins, rings, and bearings?

 

[cmher18]

Hey Chris, does your quote include forged rods, ARP2000 bolts, forged pistons with tool steel pins, rings, and bearings?

MMR 4340 Forged H-beam Rods with ARP Bolts

Manley Forged Pistons with tool steel Pins

Hastings or Speed Pro Rings

Clevite Rod and Main bearings

 

[DropTopPony]

I was full set on staying with my stock crank but found a sweet deal from the guy i bought my Teksid from and thats why i have the Cobra crank in my parts collection.