I seem to be finding most people saying 7,000 when I searched, but the opinions range from 6,500 (stock) to 7,400 being the point which you can go to without getting valve float.

Thoughts??

 

GM specs say the failure point for valves is at 7500 RPM. I would say that the max safe you would probably want to go would be 7400.

 

i would say less than that depending on which numbers gm used. if they really fail at 7800rpm but gm is being conservative and said 7500rpm you should be ok. but i wouldnt run them at 7400rpm if theyre supposed to really fail at 7500m

 

I'm runnin 7400 but I don't usually shift that high.

 

id stay with 7 grand.

 

Im at 7200 but onl changed it yesterday. And won't see that high again until the track.

 

If it helps, another limiting factor on the engine rev are the balance shafts. They are not designed to run over the stock limit. I don't even know what a safe amount over 6500 would be.

 

When you do take it up to 74k do you feel any power loss or does the car keep gaining power?

 

how good do you think the balance shafts are.
I'm bumping my limiter to 8k.

 

I'm sure they feel 7k is okay, since they raise it from 6500 to 7000 with Stage II! I wouldn't run 8k if the fail limit is 7500-7800! But that is my opinion!

 

That's what I was thinking - if they raise the limit with a stage reflash then they obviously feel that is near close to as safe as the 6500 limit. Otherwise, why would they risk bent valves and having to pull the head off a car still under warranty? I'm running 7,000 now, but thinking about running 7,400 in first and maybe 7,200 in second so I can shift it right at 7,000. The car keeps making more power and is still peaking when it hits the limiter at 7,000 now

 

if anything id go 7200 or 7300 but id always shift at 7, just so i dont run the risk of bouncing of the red line.

 

I run 7100.

I know some people do 7400 with the stock valve train.

If GM is warrentying 7000 with stage 1 I would say 7k is a safe level.

 

I heard the stock block is balanced to a good 8800 or so rpm.... anyone research that? cause once I do cams and springs next month I was lookin to bump it up to 8000-8200 rpm

 

I would check the build book for the ecotec I think they have some info on it. The 300 HP LSJ build up replaces the springs and balance shafts. They replace the shafts because the rob HP from the engine.

 

Do the cams even support power up that high!?!? It seems like you would need a pretty serious set of cams to accually make power up to 8k!

 

thats why the stockers are comin out...

 

Like I said on my dyno sheet the car is still climbing and then holds peak power from 6800-7000. I'm not sure when it would drop off but I think around 7,200 with the stock camshaft size you would start to see a drop off that peak.

 

thats exactly what I did.
I just have to change my injectors, swap my pulley, and get it tuned.
I have the JBP Stage 2 cams, and complete Bates valve train. (Check SIG)
I'll tune to about 8000RPM limit.

I know my cam's are making seroious power on the top end, and have alot more to go.
but a tune can only say for sure.

 

definatley keep me posted on that setup... thats what I'll be doin next month

 

I haven't been able to find any information on the rev limit for the neutral balance shafts. From what I can deduce, they should be good to somewhere around 8000 RPM.

 

straight from GMPD, 7200 is safe but they recommend strongly putting in bates springs and gm neutral balance shafts.....

 

The GMPD neutral shafts have been safely revved to over 10,000 RPM. That's why they exist, unlike the stockers they are perfectly balanced- hence "neutral".
Wop

 

How much $$$ and time to install are we looking at here?