Was talking to the guy redoing my LS-1 motor today and he told me something that I thought might be of use to some here on the forum. He's one of the best 3rdgen builders and tuners that I've seen, and I saw what he was talking about firsthand. We were discussing ARP bolts in the bottom end. It seems that the stock bolts, when they let go, always give out in #5. When it goes, #5 swings over, takes out #6 and sends it through the block. He said that he's seen it time after time and it's always one bolt on #5 that is the trouble maker. He showed me an example that he keeps in his office and I'll tell ya brothers, it was UGLY. Haven't seen something like that since the Detroit that went into overspeed and finally sucked a valve. Just thought I'd relay that little tidbit to any who plan to cam or run your LS1 hard. ARP rod bolts might be a pretty good investment.

 

Thanks for the info! Much better to find out the easy way. (Somehow things like the hard way for me)

 

Seems there is a debate over using the arp fasteners too though. Some guys say it squeezes the big end out of round and distorts it. Others claim it is fine though. Decisions, Decisions. Oh, did he mention if the rod bolts that fail are usually pre 2001 bolts or all of them. I think the 2001+ had some better bolts that are not torque to yield. Just wondering if those are supposed to be weak too.

 

Mostly the problem has been with '98s. (Of course, I would have a '98 ) But I think you're right, pre '01.

 

No problem so far and I've spun it to the rev limiter. I hope that was the rev limiter. I just received a 6200 msd pill, so that should help with the shifts.

My motor is a little noisey at idle which scared me at first. I then went around and listened to other LS1's. After doing that, I was convinced they all have some piston and valvetrain noise. With the hood closed you can't even hear it. My guess is that a alum. block resonates noise out easier.

 

Yup, I drove a 1 year old C-5 and it sounded like it had the rattles which offended my mechanic's ear. I talked to some folks, all said it's normal.
Most of the problems I think were from when folks were beating their cars. One guy lost his from having a stock bottom end under pressure.

 

The LS1 has quite a bit of piston clearance. This causes some piston slap in customers motors, but has never amounted to a recall. GM reshearched it and came to the conclusion that is was not causing damage to the motors. Most problems were cured with a oil weight change.

I'm still using the cheap oil that I put in it at start up. I'll probably switch to a diet of Mobil 1/GM oil filter soon.

 

Let me know how that turns out. Never used a synthetic before, it might be just the ticket? Dunno.

 

On the rod bolts: I went ahead and put the ARPs in my motor while it was apart. Cheap insurance, I figured. The issue with them coming apart wasn't an issue if you keep the stock rev limit. It's when these drag race guys try to spin a stock shortblock to 7k every weekend. That makes for a short life. My rev limit is currently 6500 and I probably won't go over that but while the motor was all apart, I figured the ARP bolts were worth the few bucks that they added to my machine shop bill.

Oil / Noise: I'm running Castrol 20W50 to keep my pressure up. My motor was built loose (bearing clearances are on the high end of the spec) so it takes a heavier oil to keep the pressure in the "acceptable" range. With my cam and springs, I have more valvetrain noise than I thought it should make. The engine builder listened to the car and said "That's how a cammed LS1 sounds. Now take it to the track and let me know how it runs...." The sound has been described as "like a sewing machine". Synthetic oil might help (I've been running Mobil1 in my 5.3 Silverado for 3+ years and it did quiet the cold-start-piston-slap down a bit) but the same engine builder told me not to bother with it in the Vette. He said he runs the $0.99 cheapie stuff and just changes it at 2500-3k miles. I don't know about you guys, but up here in the cold states, that's almost an entire summer's worth of driving on one oil change somewhere in the middle.

That's my 2 cents. It's worth what you paid for it.

 

Why is it always the #5 though? Anyone know?

And, yuh, LS1 are some clattering engines. Every one of them I've ever heard was like that. Co-worker has a cammed Z28, and it seriously sounds like he's a got sewing machine under there. But then again you can only hear that when he doesn't have the exhaust cutout open, so it's all good.

 

May be , Scooter, but your .02 is worth most people's whole dollar.

 

Dunno, but if I had to guess, I'd say it was something about the design of the bolts before they changed it in '01