99hugcam

iTrader: (9)

I am rebuilding my shortblock on a budget. I'm already in waaaay over my head as it is, and I have gotta get this thing out of my garage by spring. Polished stock crank, sdpc speed pro piston kit (rings, main & rod bearings, arp rod bolts).

Question is, are my stock rods gonna live? I know to most people the extra money isn't a problem and they would say do it. BUT I am trying to buy a house and every little helps. This engine will be topped w/ ported ls6 heads and some stuff from Ed at flowtech.

The engine might see a 150 shot at most. Will the stock rods w/ arp bolts make it? Also, are the stock ls1 rods "cracked" because if so then I'm screwed. Machine shop mixed them up. How to tell which cap goes to which rod?

Thanks for the help in advance.

GuitsBoy

iTrader: (4)

Stock rods are indeed cracked. Might be able to match them back up very carefully. The stock rods once upgraded with new bolts are pretty stout. Theyve been proven fairly reliable past 550 HP.

99hugcam

iTrader: (9)

Ok, anyone have a good way of matching the rods w/ the caps? Damn machine shop.

kp

iTrader: (34)

The caps will pretty much only fit on the rod they came off of. Just snugging the cap down should make the parting line almost disappear - I never mixed them up but it should be easy to figure them out.

FWIW I have been running the stock rods with ARP bolts all summer and I am making over 700fwhp and they still are going. I am going to do a new shortblock next season but I was surprised they held up. I ran the car at least twice a month and have over 150 dragstrip passes and who knows how many street tuning blasts..

Spade

iTrader: (26)

Hey KP, what kind of pistons are you running? What is your comppression?

Wet 1

iTrader: (4)

The stock rods are pretty stout. Mine held up fine at just over 700 rwhp @ 6700 rpm.

High rpm's are what will kill them, with good bolts I wouldn't recommend spinning them past 6900 and they should last for a long time. Anything over 7k is really getting into the grey area IMO. >7400 and they won't last long at all!

FastKat

iTrader: (10)

Yep, high engine speeds kill rods. Stay with the lower engine speed and you'll be MUCH MUCH better off.

kp

iTrader: (34)

Wiseco fat tops with -2cc reliefs ad stock 98 chambers/GM graphite gaskets, compression is probbaly right at 9.9:1 or so. I'll find out exactly when I CC ihe heads in the next couple days..

Keeping the RPM under 6800 is a good idea with stock rods, so is light pistons. My rev limiter is set at 6700 and I hit it almost every pass, i'd like to shift at 6800 but I leave it set at 6700. Like anything else moderation is the key to long life

bulletLS1

IF the shop didnt TIGTHEN the caps youre OK,
BUT if they are torqued or tigthen in any way in the wrong rod... well... youre_________ (fill the blank)

because even thou you find the correct rod-cap combo all the micro ridges that left the "cracking" procces will be deformed, hence "no fit" or wrong gap or oblong holes, or no "crush" strength.

my shop broke oil p sesn, water em sens, a couple of bolts... in the first day!
then on I DEMANDED to be present in all machining operation....
whenever I looked around they seems to use their favorite tools... hamer and chisel!

is an exercise of patience and good eye buy you have to try harder!!!!

Good luck and greetings from sunny Guatemala...... hahahahaha all of you that already have snow!

Rhino21149

Well, we bent a rod and blew the engine on a 98 which we built at a bargain using what we thought were good stock rods (they came with the car, we just rebuilt the bottom end, as discussed here). It had about 70 1/4 mile passes in N/A (390 RWHP) and +125 NOS form (518 RWHP) and we had done 2 passes on this +175 set up earlier that day and was almost wound out in second on the third when it began howling and let go before my son could shut it down. We didn't think it should have come apart, but it did. Might have been a rod bearing that went first, but it sure sounded and acted like a bent rod (and we sure found would very twisted rod among all that mess).

99hugcam

iTrader: (9)

hmmm, below 7k rpms you say. These might not work after all then.

GuitsBoy

iTrader: (4)

I dont know, plenty of guys are spinning the stock rods faster than 7K after doing rodbolts. Maybe its playing with fire. How far were you planning on taking them up to?

FastKat

iTrader: (10)

Hmmm... wonder if $280 forged SCAT I-beam rods would be good for your budget?! I am planning on using them in the near future...

99hugcam

iTrader: (9)

If I do end up buying rods, the Scat I-beams where the ones I was planning on getting. I'm not sure of this time exactly what rpm I will be taking them to, kind of depends on what Ed gives me. I am going pretty extreme w/ this one though, so I am thinking it will be somewhere around 7,000. At least I would think?