greenjeens

I'm curious, I have heard that some vortec engines and maybe some factory TBI engines have had factory forged crankshafts. If I were looking for a factory 1 piece seal "forged" crank, does anyone know what motors these would come in? Someone has a rebuilder 97 vortec for 75 bucks on C's list. That has a nodular crank, right?? It would have to be 350 crank. There's several junk yards around here, and I would like to find a nodular or even a forged crank on the cheap 1 piece seal.

vetteoz

iTrader: (13)

The only late model engines I know of with a forged crank are the Hp crate engines
The L31 Vortec engines are listed as having nodular cast iron crankshafts

customblackbird

iTrader: (15)

aftermarket scat cranks are stronger than any other cast crank out. can handle 550hp and are designed to be spun to 6000rpms. they are like 200-220$. even if thats too much, eagle cast cranks are stronger than stock nodular cast cranks and can be had for 189$ from summit. the cranks are crazy cheap esp when they are better than stock and BRAND NEW! dnt mess with a used crank just get a new one so the tolerances are exact.

ziggy89

for the money go with a scat or eagle cast crank.

im running 13.0 on my bottom end. eagle cast crank I beam rods and hyper pistons.

and its a godd time for more cubes. 383 rotating assembly for 550 is wat i paid

86LG4Bird

iTrader: (1)

Complete misinformation!
Scag and Eagle cast cranks are both inferior to GM cast cranks. Unless you're going forged, you are not upgrading.

88fastgta

iTrader: (9)

i have a forged eagle 4340 steel crank im my GTA... that puppy was around 600 dollars just for the crank... MUCH MUCH better quality than any cast crank...

vetteoz

iTrader: (13)

This guy might disagree with you
http://www.pacificp.com/forum/viewto...er=asc&start=0

Fast355

iTrader: (2)

2-ton truck...C60 with the 350 TBI....Factory Forged Crank, 18cc dished hyper pistons, factory roller cam, and factory piston cooling oil squirters in the block.

customblackbird

iTrader: (15)

yes ive already known about that site and that incidence wit the broken eagle cast crank. Ive heard some bad things about eagle and there hardening process. when i ordered my rotating kit from CNC motorsports the tech guy said not to go with eagle cast cranks. they had broken 3 of them in one year. He informed me that the scat cranks are much stronger and have a better/deeper hardening process.

lets get something straight, GM cast cranks are fine, im not talking about the more recent ones... say 95 and newer. but its known that stock GM cranks from lets say an 87 firebird 350 L98 can be pushed to 350hp and be "safe" but if u push that same crank to 500hp your gona break it. newer cranks have better metals and better hardening processes.

the cast 9000 series crank is an UPGRADE to a stock cast GM crank, the 9000 series is a stronger material. the scat crank cost alittle more than the eagle and scat cranks tend to be harder to balance. older GM cranks arent lightened. the crank throws are not lightened, they are solid. in case u dont kno, more rotational weight is not good for a CAST crank. so for you to say that a scat crank is not an upgrade to a 20yrold cast crank made with 20yrold technology is just stupid.

other things to consider are the blocks. a cast crank should never be spun higher than 6000rpms, they do NOT like detonation and forced induction/power adders, they do NOT flex like a forged crank does, they just crack and break. blocks that are 2bolt are plenty strong if u dont spin above 6000rpms, 4 bolts add stability to keep the mains from walking but this is only evident in higher RPM ranges like 5500 and above. A 4 bolt is stronger than a 2bolt for that purpose but they are also weaker, 4bolt mains are drilled and tapped (outer 2 bolts of each main) at the weakest point in the block, they tend to break/crack at the point due to too little material, not to mention the manner they are drilled (all are drilled straight down). the ultimate would be a splayed 2 bolt block. the outer splayed bolts are stronger than the stock 4bolt mains bc of the angle they are drilled, they also drill into a meater part of the block. much like the newer LS blocks have side drilled main bolts.

customblackbird

iTrader: (15)

if your gona make a statement like that u should post information to help your argument, yet u post no supporting information, u just make accusations and therefore u post means nothing.

forged cranks are not needed for 90% of the motors out there. they are the strongest crank besides billet yes, but not needed for an engine that doesnt spin above 6000rpms and isnt making insane power. and throwing a forged crank in a 2bolt is just plain stupid since the mains will break before the crank. U match the components to the engines needs. aftermarket cast cranks have been used in 700hp forced induction engines and live, try that with a stock cast GM crank ha.

88fastgta

iTrader: (9)

hey customblackbird.. does that apply with eagles forged cranks. i was orginally going to get a cast eagle crank but i decided to get there best crank which was the 4340 crank... i got i just to make my short block stronger.. i also have eagle forged steel rods.... my dad and i were amazed of how much better the quality is compared to the stock crank we pulled out of the l98...

customblackbird

iTrader: (15)

no it seems eagles issues are only with the cast cranks. from what ive heard the eagle forged cranks are fine. the rods are fine too. i know what the stock crank looks like. i have mine sitting in my tent next to my car, that i just replaced with the scat rotating kit in my 383 in my sig.

the stock L98 crank i have is sooo D@MN heavy, its funny to even think that the stock crank is stronger than the scat 9000 series crank i just stuck in haha.

are the eagle rods with ARP cap screws? your bottom end is pretty stout for a NA engine with L98 heads. depending on the pistons your running you can easily hit that with gobs of nitrous/a nice PSI and be fine

88fastgta

iTrader: (9)

the stock crank does seem heaver than the forged eagle crank we put in...yes i have arp bolts in them i also have upgraded h bearings and heavy duty cam bearings..... my rotation kit cost me nearly 1600 dollars.... i just wanted a nice foundation to work with if i ever decide to add more power to it...

here is my bottom end
fresh 355 bored .30 over 4 Bolt Main Vortec Block
10243880 Gm cast Block
Blueprinted Performance build ( bored with thrust plates)
9.7 to 1 Compression
Milodon Main Cap Bolts
Eagle 5140 Forged Steel "SIR" Lightweight Connecting Rods
ARP Rod Bolts
Eagle 4340 Forged steel crank
Upgraded Clevite 77 H Bearings
Kieth Black Hypereutectic -12cc dished pistons
dura-bond hi performance coated cam bearings
Pioneer heavy duty brass freeze plugs
Internally Balanced Eagle rotating assembly (rated at 650 horsepower)

would you add nitrous to this bottom end.. would u consider this a strong bottom end i probably overdone it with my build.. i could probably easily spin this motor to 6 grand with no side effects

greenjeens

Thats what I was looking for, I wonder what the chances of finding that motor in some wrecking yard? This thread really woke up. After reading all of this, I am definetly going to spend the extra dough for a 4340 forged crank. I already have a LT4 4 bolt block. Why through in a cheap crank, and have it fail when I decide to wail on it.

greenjeens

This motor is more what I had in mind, sounds like a good solid build.

customblackbird

iTrader: (15)

exactly greenjeans, dont skimp out. but get what u can afford. u can wail on a cast crank but they are limited by RPM and power output. if u gona be making more than 550hp or spinning above 6000rpms on a daily basis then i would go forged.

88 fastgta... couple of things. no i wouldnt hit that motor with nitrous. heres why, u have a strong bottom end, the crank is good, the rods are better than stock but they arent the strongest. the 5140 forged steel in the eagle SIR light weight rods are strong but they arent as strong as 4340 forged rods like the scats. i forget how much of a difference they are in strength but its a good bit. esp when it comes to a rod which sees extreme forces.

i also dont trust anything as far as fastners/bolts except for ARP, ive never had an ARP bolt fail, yet ive broken milodan and moroso bolts also manley. i would have gotten the ARP main bolt kit and if you had it alignhoned i would have gotten studs since u need that done when using studs bc they clamp more than bolts. im running the ARP main bolts, cam bolts, rod cap screws, head bolts, oil pump stud, flexplate,tq converter bolts, intake. all ARP so i have peice of mind.

the last thing is your pistons which is why i wouldnt run nitrous or any power adder. the KB are a good piston but the do NOT like any power adders. they are hyper pistons which makes them stronger than cast but weaker than forged. you didnt really skimp on ur kit but u got some weak components which totally negates that point that your running a good forged crank. so now what uve created is a weak point with the rods/pistons and these will break before your crank. you run nitrous with hyper pistons and u playing with death. u can get away with it if u dnt encounter detonation but i wouldnt do it.

if you really want to run a power adder your gona have to tear the motor out and pull the pistons at a minimum, and run good forged pistons. im running the SRP forged dish pistons and they are rated up to 300hp NO2 shot with no worries. but if i was pulling the motor i would get some good 4340 rods and put some ARP main studs in then u really got a STRONG bottom end. im not saying yours isnt strong but u cant really do anything with it as far as extra power unless is Naterally aspirated (better heads/cam etc) bc the pistons cant really take a nitrous hit or forced induction. otherwise ur kit looks good. my kit cost me 1200 balanced.

heres some food for thought. my friend runs mustangs, hes got 2, one he races. this car has the stock 302 V8 and it runs stock 2bolt mains, stock cast crank. he was running explorer heads, FORGED pistons, stock rods and a cam with a 150shot of NO2 and hes running 11.5s in the 1/4. with no issues with the motor, yes stock CAST crank and 2 bolt mains. spinnin the motor to 6500 easily. he will easily see low 11s with his aluminum head upgrade hes doing now. his other mustang is a show car that he drives in nice weather and its a 302 with forged pistons, stock CAST crank, stock rods, but has a holley cam, holley heads and intake but hes running a procharger with 12-14psi and hes making something like 414rwhp on the dyno. just proving that cast cranks can take a beating and keep going. i would never use hyper pistons unless i knew i was NEVER gona run a power adder.

88fastgta

iTrader: (9)

i know that im not going to run any power adders.. i dont like N02 either... i just wanted to know if my bottom end is more than strong enough for what my build is now.... this motor is a daily driver street motor.... no racing for this motor..

customblackbird

iTrader: (15)

well then ur bottom end is over kill. a scat cast crank, forged rods and the KB pistons would have been overkill for your car and u could have saved alot of money.