Hi all:
In short, I'd like to get a notion of how safe I can feel revving stock Chevy rods (180,000 psi bolts) that reciprocate 610 gram forged pistons to above 6000 RPM but not higher than 6500 on occasional basis. This is because of the peak of the power curve occuring around 6 grand (check the link below for the power graph of the setup i'll be using). The heavier forged piston is what raises my concerns, although if I had cast I'd still want to check. The motor is a 355 sbc (400 - 450 hp expected) going into an automatic 1990 camaro which is not a daily driver but will be used on nights/weekends for street fun, occasional track.

I'm looking for input from any experienced person that has ACTUALLY put stock chevy rods through hell or experienced someone do it. In my opinion, you can analyze and make theories all day, but testing proves! I'd like to hear some stories. Have any of you actually experienced a stock rod failure?

I'm already aware that it would be a safer bet to use stronger rods. I'm not trying to be impatient, I'm just so far in the build that it would be very expensive & time consuming to go back, uninstall, buy new rods, rebalance the assembly and reinstall. Of course if it is too risky to use the stock rods, then I must rebuild because then I would waste much more money if the motor blows.

I am building a 355 SBC. Here's some specs:
Reconditioned 350 roller block, 30 over
NEW Scat stock replacement crank
Reconditioned stock rods w/ 180000 psi rod bolts
NEW Speed Pro pistons, forged, mass of 610 grams (heavy which is why i'm worried)
Assembly balanced and dampened w/ fluid filled dampener

Vortec heads (Engine Quest brand) modified for higher lift
Edelbrock 2204 Hyd. Roller Cam
Edelbrock RPM Pro Flo EFI kit #3507 (check it out, very sexy - http://www.edelbrock.com/automotive..._chevy_sb.shtml)
Roller rockers

Since my motor will be very similiar to Edelbrock's 440 HP EFI crate engine, I think it is safe to say that dyno results would be very similiar to Edelbrock's. Check out the power/torque graph for the EFI kit I posted the link for above.

Thanks!

Well in my 400 i have stock 350 rods (the heavier duty 70's style) with arp rod bolts and i spun it passed 7k once and 6k a few times and i never had any problems but that was all by accident

ok, good to hear something,
Thanks for replying.

I had Stock rods in mine and I ran it past 6500 many times. Had it when I was in High School and I rodded the crap out of it,,never had a problem with them.I don't think you have to worry unless your going to exceed 7000 rpms and 500 pounds of torque.Aslong as its been balanced and put together properly.

a friend of mine from school had a 65 impala, 283 bored to 289, forged pistons (from the swap meet none the less) and the rest was all stock or stock replacement from the local autozone

the bottom end was balanced and assembeled to "reman" quality ... not to much detail, not to sloppy ... just average

now being that hes a georgia boy, and his uncles farm was used for some of the dukes of hazard episodes ....he had the perfect place to practice his back roads driving

that engine was 4 years old by the time i met him, and we put another year of back roading on it during school, and i last talked to him like 3 years after i left, and the engine was still running like it was showroom new

i saw 6 grand at LEAST 3 dozen times on the "straight away" north of laramie .... and way more times then that on the curvy roads .... and twice we accidentaly peged the 8k tach, both times because the 700r4 shifted from 4th to 3rd @120+

if the tack was accurate, the engine hit 10k .... because that needle was WAY past 8 ...

granted its a 289, so theres less piston weight .... and chances are it was one of the rare cases where the engine just for what ever reason just wont come apart ....

The team that i used to build late model engines for had a back-up 358 that turned 4500 off the turns and 7800 plus at the end of the straight-away.. stock rods with arp bolts... zero issues...

Your results may very!!!!!

Keith

__________________
K-Star Automotive
Performance Engines
It's better to have a gun and not need it, then need a gun and not have it.

Don't cheep out on the rod bolts ( I used the ARP ) and you should be OK.

I'd be worried about pulling the pin on that grenade your calling a piston.

Stock connecting rods are fine for 6500 RPM. A stock 2 bolt, cast crank, cast pison, stock rod bolt 350 is good for 6500 RPM as far as that goes.

However, there are such things as "cycle life" and "forging flaws", which you cannot detect, so there are those times when things go "bam".

"High performance useage, no warranty, expressed or implied."

heh, bad experiences w/ speed pros? or are you referring to something else?

[QUOTE=lowROLLERchevy]a friend of mine from school had a 65 impala, 283 bored to 289, forged pistons (from the swap meet none the less) and the rest was all stock or stock replacement from the local autozone

we accidentaly peged the 8k tach, both times because the 700r4 shifted from 4th to 3rd @120+

if the tack was accurate, the engine hit 10k .... because that needle was WAY past 8 ...

QUOTE]

Another 1/2 inch of stroke makes a LOT more stress on the rods.

Stock stuff runs fine right up to the instant it blows. Usually unexpectedly, suddenly, and spectacularly.

I'd put a 6000 rpm rev limiter on it...