Limits of OE 6 bolt rotating assembly? (ARP hardware)

[GSR-VR]

I'm sure most of you have seen the videos of the 700 all wheel horsepower Talon on the stock shortblock and I'm curious what all of your opinions are on the stock components. I think we all can agree that the stock 4G63 is very strong and with proper care in tuning can achieve great power. This is my question: Is there any reason why a balanced and blue printed stock shortblock with ARP hardware cannot survive for some time at 9000 RPMs? (to further disambiguate assuming a proper head is built to handle said engine speeds)

 

[90laserRSfwd]

ASSuming... The engine is setup lose, and your oil system can avoid starvation, yes, it will last at 9k for a reasonable amount of time..

 

[curt-s]

That's a lot of mass in those rods to be flinging around.. I wonder if they would stretch because of the sheer velocity.
Anybody have the calculator on that?

 

[NordicSaab]

Im not really sure what kind of response you are looking for here?

MY can makes 606awhp on a stock bottom end and will rev out 9K. Only real changes have been uprated (Kiggley Beehive) valve springs and ARP hardware where appropriate.

I track and autocross and this setup has now lasted a full season, but realistically it could blow at any time.

 

[90laserRSfwd]

The rods wouldn't stretch because of velocity. If anything the rod fasteners (bolts) would let go or you'd see a wrist pin failure. Drilling a second top oiling hole, coating the piston pins, and cyro treating them is an option as well. The main problem is the pins wall thickness, as well as, them being a press pin design. Not to say it's nessacerily bad, but full floating pins would be better. Hope this sheds a little insight..

 

[curt-s]

Interesting. I'm wondering the total kgm of force they're subjected to on the stroke change +v -> 0 -> -v and its effect on the entire rod including cap (but not fastener hardware) and what rpm is needed at stock stroke length before deformation occurs in the cast iron.

 

[303_2G]

As far as the bottom end is concerned I believe that it can handle 9k for a long time (in very fast shifts not keeping it at or above 9k for more than a few seconds) And I know your talking shortblock but the concerning part is the head at that high rpm. Your valve springs won't like it one bit but with easy spring & retainer upgrade that'll get you that much farther.

 

[GSR-VR]

Thanks for all of your responses!! This is just what I wanted to know. The amount of DSMs in New Mexico that actually reach anywhere near 500hp or 9k is few and far between. Since I plan on running two stock bottom ends with kiggly's street beehives I should be happy knowing this! Thanks so much everyone!

 

[303_2G]

Dsm's.. here? Do you mean where your from there's no 500+hp Dsm's around?

 

[GSR-VR]

The rods wouldn't stretch because of velocity. If anything the rod fasteners (bolts) would let go or you'd see a wrist pin failure. Drilling a second top oiling hole, coating the piston pins, and cyro treating them is an option as well. The main problem is the pins wall thickness, as well as, them being a press pin design. Not to say it's nessacerily bad, but full floating pins would be better. Hope this sheds a little insight..

Even with ARP rod bolts?

Dsm's.. here? Do you mean where your from there's no 500+hp Dsm's around?

Yes, where I am located 500+ awhp DSMs are few and far between.

 

[90laserRSfwd]

The ARP rod bolts would probably out last the stock wrist pins. I have not seen ARP rod bolts for 6 bolts fail recently IF the big ends of the rods were resized correctly. Like 303_2g said, it's more likely the valve springs would fail long before ARP rod bolts

 

[GSR-VR]

The ARP rod bolts would probably out last the stock wrist pins. I have not seen ARP rod bolts for 6 bolts fail recently IF the big ends of the rods were resized correctly. Like 303_2g said, it's more likely the valve springs would fail long before ARP rod bolts

Understood. I thought I mentioned that a properly built head was a part of the equation here. Since 4G63s are interference engines I can agree with the thought that 9,000 RPMs on stock springs is NOT a good idea.