Stock crank with 300hp

[cruisintalonawd]

Will it withstand the power??

Note:this is a 6bolt crank

 

[blcknspo0ln]

Many have sneezed 300whp on a stock crank. Most have gone and pushed these silly 6/7bolts to over 600 whp now-a-days. Why do you ask? I wouldn't fear of crank failure at that power level (unless you're spinning the motor much higher than you need to be).

 

[cruisintalonawd]

No I would shift 500rpms bfore redline but I need a running car again that I'd be modding but I dont think I would even make that much but I was just over estimating the number

 

[dsm-onster]

Any crank that would fail at 300hp would be weak. The 4g63 cranks are no weakness. 6-bolt rods/pistons can withstand well over 500whp with that stock crank. The rods/pistons are the weakness. That same stock crank w/ forged rods/pistons is a formitable build: the rods/pistons would still be the weakness.

The crank has been known to handle whatever you can throw at it, WRT cylinder pressures. As blcknspo0ln said, if you don't rev it to a WILD number (10K +), then you're crank is fine for very much more than one would want to take on public roads.

 

[cruisintalonawd]

Ok thanks

 

[erald01]

Wouldn't worry about the crank at 300 hp, because our cars brand new made around 225 hp. I know guys that make 450 whp. I have a stock crank on my 7 bolt and i'm making around 315 whp.

 

[cruisintalonawd]

ok and I can get Forged pistons and rods for about $500 will those with stand

 

[peypey's ride]

The 4g63 cranks are no weakness. 6-bolt rods/pistons can withstand well over 500whp with that stock crank. The rods/pistons are the weakness. That same stock crank w/ forged rods/pistons is a formitable build: the rods/pistons would still be the weakness.

Like he said in the previous post! +1
They will definitly handle well over 300hp if you get the forged pistons and rods.

 

[dsm-onster]

ok and I can get Forged pistons and rods for about $500 will those with stand

Which brand forged pistons/rods. Anything forged likely is 600whp capable. . .

 

[cruisintalonawd]

I don't know they just said mitsu replacesments

 

[erald01]

If you have the money for the forged pistons and rods then go with it, but as far as i know 1g cars with stock internals can withhold up to 400hp. It also depends how many miles you have on your stock internals. Forged pistons and rods are made to withstand 400hp and more when it comes to our cars at least.

 

[dsm-onster]

If you have the money for the forged pistons and rods then go with it, but as far as i know 1g cars with stock internals can withhold up to 400hp. It also depends how many miles you have on your stock internals. Forged pistons and rods are made to withstand 400hp and more when it comes to our cars at least.

I've personally seen 230K miles 6-bolt rods roll out 490whp . Mileage usually "seasons" blocks, pistons, and rods.

cruisintalonawd, I'd first determine if you have a 6-bolt or 7-bolt. The transition happened in the middle of the 1992 model year. How to quickly tell a 6bolt and 7bolt engine apart. The 6-bolt is a 500whp factory block. Plenty durable! Again the crank can handle gobs of power but the 6-bolt rods are significantly more forgiving.

 

[project_tsi]

Older blocks and cranks are more dimensionally stable (residual casting stress has equalized out), DEFINITELY NOT STRONGER. This happens more with age than mileage.

 

[cruisintalonawd]

yes its a 6 bolt thats the first thing I check before I bought the car
YAY!!!!

 

[97 4G63]

You should be fine for 370hp whit a 6bolt if you do a stock rebuild..

 

[cruisintalonawd]

ok thanks

 

[project_tsi]

I my self am turning close to 600 whp with a stock 6 bolt virgin crank, meaning stock sized bearings, etc.

 

[cruisintalonawd]

Thats sweet

 

[fp-green-95tsi]

Stock cranks have made over 1000hp and been reved over 10k. Stock long blocks will handle 500+WHP easy with a good tune.

 

[greentrbo_95gst]

You will be fine even at 500 whp. We have seen many stock applications at close to or at 500 whp. Same thing goes for your bottom up. My own personal car is over 700 whp with the stock crank. Good luck.

 

[dsm-onster]

Older blocks and cranks are more dimensionally stable (residual casting stress has equalized out), DEFINITELY NOT STRONGER. This happens more with age than mileage.

I did not know that it was more age-dependent. . . Though that makes good sense. Stress-relief heat treating should be done uniformly and cooling should take place slowly where varied section volumes are present. Neither neccesary characteristic is found under the hood .

Increasing 'fracture toughness' via age of an older block versus the 'fracture toughness' characteristic of a newer block would lead me to believe that the older block is stronger and can withstand sharper shock. Does equalizing the residual casting stress cause a component to frature at a higher load? Or is that a totally different animal?

 

[cruisintalonawd]

Are topline pistons forged

 

[95blackGsTurbo]

I just answered this question. If you asked it here there was no reason to start a new thread in the this forum. Would have gotten an answer 10x faster in the newbie section.