I made 390/378 with my 306 with le heads 2800 stall with 4.10. This was an open header tune as well. On a rich as tune we ran out of time since the knock sensor went bad and was reading false. On a 150 shot ran a 7.10 8th mile spinning and ran a 6.89 with a 175 shot with a sweet 1.69 60 on street tires. Then we spun all rods trying to tune it for a 200 shot when it over rev to 7k.

 

My cam only freshly rebuilt LT1 blew the **** up after hitting 6600 RPM Forged H/C/I 383 in progress now....looking back I personally would not push a stock LT1 past 6400 rpm unless you have deep pockets to afford a re-build or new motor; ask somebody who knows all too well

 

Ahritchie, did it actually BOOM and lose it's guts or just spin a bearing?

 

LOL....Yea it was quite the BOOM...sounded like a grenade in my engine compartment...scared the **** out of me, it was on the track and spilled oil/coolant everywhere. Took the track crew 20 minutes to clean all that **** up Others seem to get away with spinning a stock LT1 faster than that...but they are pushing their luck if you ask me. Would have/should have/could have put some ARP rod bolts in it at least but I didn't....now I'm starting over doing it right (all forged) to handle some RPM without blowing up.

 

Revving to 6600 did not cause your engine to blow...

 

OK,then WTF did then!? It ran fine and was in one piece before it was over-revved; so what exactly are you suggesting...don't give me that "driver made it blow up" bullshit...I'm fully aware I'm 100% to blame for not shifting sooner....let me guess...It wouldn't have blown up if I drove a womanly (automatic) transmission

 

Another pointless post by gregrob. Hey at least this time he didn't create a new thread.

 

My guess would be shitty machine and / or assembly work. 6600 RPM wont hurt a properly setup combo, even in a stock short block.

Oh, and GFY Joe

 

Nobody gives a about your guesses or speculations. If 6600 RPM is soooo safe...why the **** does the sticky at the top of this page clearly state:

"If you are in the market for a camshaft purely for sound and are willing to sacrifice usable power and drivability then something along the lines of the cc306 or GM847 will suite you well. However, if you want the full potential out of these cams you will need to be shifting at 6400+ rpm which is VERY risky on the stock bottom end. Some have been lucky while others have not but a stock block typically will not last long if being shifted at or above 6400/6500rpm."

 

That sticky is someones opinion which is based more on hearsay than experience. If you think revving to 6600 took out a fresh properly built shortblock, you're high.

Ill be sure to tell it to my old engine (still currently going strong) and all the other stock shortblock cars I know that there's something wrong that their **** hasn't blown up. I heard on the internet it couldn't be done

 

Well call me a rasta man then! I'm telling you MY motor was fine for over a year, 8000 miles before it was over-revved to 6600 and blew up...it spun to 6500 MANY times before with no issues. This is a fact. You are the stoner if you actually believe every LT1 motor is exactly the same with the exact same breaking points...BULLSHIT. Whether you like it or not LT1's can and DO blow up...hey that's great your motor is fine...you want a cookie or something? I never said no stock LT1 can take over 6500rpm....all I said was I personally would not do it and LS1 tech advises against it too, but I guess you know everything already right?

 

sorry this had me LOL'ing

 

Ive been revving mine to 6800rpm for almost two years. Cammed it at 108 has 144k on it now.

 

poor balancing and maching is what made the motor blow up, i pushed my stock shortblock for over 2 years with a 306 to 6800+ with no issues then one day bang spun a few rods. i new it was going to happen sooner than later yes. bought a junk yard lt1 spun it up to 6800 for a year and bang blew up on the 10th 200 shot and spun all the rods. a 8000 mile mtor blows up im thinking the builder did something incorrectly, unless you did not have it propely balanced.

 

All the builder did was re-ring it and put in new bearings and oil pump....that's it. No machining was required, the bores were like new. I don't see why it would need to be re-balanced due to new rings. The only reason it was "rebuilt" was it had a blown head gasket and the cam bearings was worn so it made sense to freshen it up while having the motor apart. The guy that did it was the most senior tech (40 years experience) at the local former Pontiac dealership....plenty of experience with old school 350's and LT1s....I'll have to go tell him he's full of because the internet said so

 

Could have easily been detonation on the 200 shot. How was the tune?

 

the tune was pretty good, we were rich as hell with 10 retard and were trying to lean it out more. more likely than not the nitrous killed it.

 

Rich as hell will do that. Were you reading plugs.?

 

Wouldn't happen to be friends with Steveo and all them on here would you ???

 

I know lots of tech with lots of time in the field that dont know **** about internal motor clearances and ****. Im not saying he doesnt know, just saying his 40 years really doesnt mean ****.

Ive seen too many factory lt1s spinning over 6400 reliably to believe on trip to 6800 killed it.