RPMs bitches

**johuckabee** · 02-23-2006, 08:15 AM

what is the rpm limit for a ls1 with stock internal components? is there a rev limiter? besides a rev limiter, what is the initial weak link: valve float/bent push rods, what? (drive it like you stole it)

**mrr23** · 02-23-2006, 05:08 PM

6500 max with all stock components. valve train being the weak point. factory rev limiter is 6500 rpms. valve springs just can't take the rpms. next is the pushrods. then lifters. then rockers.

really no need to turn 7000 rpms.

**johuckabee** · 02-24-2006, 03:41 PM

Say you have aftermarket springs; what rpm to you see pushrod failure at?

**hammertime** · 02-24-2006, 04:18 PM

Originally Posted by johuckabee

Say you have aftermarket springs; what rpm to you see pushrod failure at?

Stronger springs will likely aggravate the weaker pushrods, you may not even need to raise the rev limit to do some damage.

I would think the lifters and rockers should be ok up to 6500 with a stock cam profile. You probably wouldn't make any power worth the risk above there with the stock cam anyway...

And since you are a six speed, if you ever get the dreaded mechanical over-rev from a 3-2 shift at WOT, you can expect to bend a stock pushrod with heavier springs.

**Mr. Luos** · 02-24-2006, 04:22 PM

My 1999 was limited at 6200. Per HPTuners.

**oneBADDz** · 02-24-2006, 04:44 PM

Originally Posted by hammertime

Stronger springs will likely aggravate the weaker pushrods, you may not even need to raise the rev limit to do some damage.

I would think the lifters and rockers should be ok up to 6500 with a stock cam profile. You probably wouldn't make any power worth the risk above there with the stock cam anyway...

And since you are a six speed, if you ever get the dreaded mechanical over-rev from a 3-2 shift at WOT, you can expect to bend a stock pushrod with heavier springs.

had a friend bend a pushrod more than once with stock springs thanks to the 2-3-2. Eventually he blamed the problems with the car on the car and sold it. This time he bought an automatic though

Bombguy99Z28 · 02-25-2006, 01:12 PM

LS1 Fbody stock revlimiter is 6200. Not sure on the corvettes.

**Sarge** · 02-26-2006, 06:35 AM

After 6200 your out of your power band anyway...what's the point? The stock push rods/springs are weak at anything above 6200...that's true...but to me the limiting factor is the valve roller lifters that "pump up" and leave you with a floating valve at above around 6500 RPM...so your toast anyway....

**johuckabee** · 02-27-2006, 12:48 PM

If you build the engine to stand 10000 RPMs and you can get it to breath up there then why not do it. What do you mean there is no reason to turn 7000 RPMs. I ride an inline four cylinder sport bike. You would be surprizeed what you can do with high RPMs and low torque. High RPMs=more air=more gas burned=more power. Revy engines have been kicking ass for years. I only wish Arao Engineering would make four valve heads for the ls1 so I could rev like a ferrari. It is simple physics. Energy=Mass x Velocity^2

**gnomee** · 02-27-2006, 01:57 PM

On my stock engine according to the dyno I dropped in hp and torque from 5500 to rev limiter. My peak performance was right at 5500

**keliente** · 02-27-2006, 03:16 PM

Originally Posted by johuckabee

If you build the engine to stand 10000 RPMs and you can get it to breath up there then why not do it.

Because there is no need to?

If you want to make peak power at 8k then get a honda or something

**Mr. Luos** · 02-27-2006, 03:45 PM

Imagine how much fun a de-stroked LS1 that spins to 9500 would be on a road course!!!

Then I remembered....I am good at 6700 with my stroker.

**02z28ls1** · 03-05-2006, 12:57 PM

Chevrolet learned back in the late 60's that NOBODY on the street can appreciate or drive a high revvin short stroke motor. Remember the 302? Probably the closest thing to a race motor a factory ever put out. You had to rev the f@c& out of it to get to the powerband but it would scream on the road course and dragstrip. But it was a commercial disaster on the street. If you've ever tried to drive a motor on the street with too big a cam(I have) you will find that it flat sukks in traffic. As much as you'd like to try it-you'll regret. It is possible to make an engine do this (I know we will hear the stories)on the street,but it's not something the major car manufacturers are willing to do. And as far as a Ferrari goes-there's a reason for that price tag.

**smokin_ls1** · 03-05-2006, 06:55 PM

Originally Posted by Bombguy99Z28

LS1 Fbody stock revlimiter is 6200. Not sure on the corvettes.

That's what mine is and wouldn't want it to be any higher with stock parts. With aftermarket pushrods and valve sprins I'd go as high as 6600 though. I really wouldn't want to be much higher than that. Probably shift at around 6600 set the limiter at 6700 or so.

**smokin_ls1** · 03-05-2006, 06:58 PM

Originally Posted by gnomee

On my stock engine according to the dyno I dropped in hp and torque from 5500 to rev limiter. My peak performance was right at 5500

Let me guess, you have an LS1 intake and factory valve springs. Right? An LS1 intake drops off at the 5500 mark. An LS6 will push that up some.

**johuckabee** · 03-06-2006, 12:54 PM

The intake, springs and any other parts can be changed. As for the part about no one appreciating a high revving engine, speak for yourself, not others. The dz 302 is one of the best engines ever made as far as I am concerned. It is all a matter of knowing where the power is and not being afraid to reach for it.

**Kyle C** · 03-06-2006, 03:09 PM

I remember being 19. I over revved everything back then.

**smokin_ls1** · 03-06-2006, 03:12 PM

Did you ever own one? Why did you get rid of it? They are nice to tinker around on the weekends with but for regular driving I hated it.

**johuckabee** · 03-06-2006, 03:40 PM

Over revved? If it breaks i will fix it, but untill then i would like to enjoy my engine, not treat it like a baby. what is the point of going easy on a fast car?

**02z28ls1** · 03-06-2006, 03:53 PM

There is no point to revving the stock engine higher than 5500 or so. The power band drops off after that. If you have deep pockets then there is no reason to not drive as hard as you please. I'd rather spend my money on other things. Like a roof over my head, and my other cars and hobbies. I wish I had enough focus for one car only in my life,but it's not happening any time soon.