billy z06

With quite a few people over 800 wheel on the zr1 without the gas and around 1000 on it.Where do people think that the limit is before they start getting hurt or has anyone hurt one yet.
And how many miles on big power cars.

timmyZ06

Few TT LS9 holding on with more than 1000whp.

TWS Racing

Infinity horsepower! Just like my Chevy Silverado.



My 2010 ZR1 just very recently got in the 800 wheel neighborhood, but was a little over the 700 mark for a long time and no issues. Stock bottom end with 12K miles. Been modded in stages at 4K, 6K and 12K miles.

JKLNHDE

Any issues experienced with the stock rear end, tranny, etc holding up at those power levels over time? Thanks very much for any info.

TWS Racing

The only thing I have broken was my clutch master cylinder. $100 part. Little bit of a pain to replace, but my own labor is free.

The stock LS9 clutch is a nice unit, but still probably not intended for the power level I recently reached. When I did the half mile shootout last weekend, I babied the car off the line. Let the clutch in easy and went part throttle through first, quickly hit second and once I was halfway through second I went WOT. That strategy was due to traction limitations, but I wouldn't sidestep the stock clutch with this power.

Frans96ss

hahahahaha

need4speedmotors

These Ls9's really are crazy engines, a few years ago, never in a million years would I have thought to see 600 hp from a mass production car.

whatcop?

The limit is when it goes boom

ace32x

mine hasnt let go yet its seeing over 1000 on a 200, just ran through 45 lbs of n20 last weekend. have a tune and jets for a 300 aswell gonna give that a whirl soon should be low 11xx

Corvettinator

And the only way you do that with an extended warranty like GM offers is building enormous margins into it. As I've said several times, the ZR-1 is essentially "de-tuned" at the factory "down" to fit into those margins. Hell, looking at the margins on most LS3's, maybe the LS9's really are infinite.

With that said, hats off to those with the brass ***** to mod a six-figure car.

Michael ZR1

If your going to run a drag radial and hook it up you need a clutch and half shaft upgrade or you will be walking home......

ace32x

half shaft? im launching mine at 5k on drs and hooking no issue

Michael ZR1

What kinda power? You can scribe them and see they will twist.

ace32x

1050 ish

Ballbearingturbo

I've been searching for this "half shaft" upgrade? Do you have any links?

Michael ZR1

Axle shafts rpm has them out of 300m

mirage2991

just some FYI:
Read a car craft magazine yesterday where they wanted to know "how much hp can a stock 5.3 truck engine can take"....well they put some boost to it and a cam, gaped the rings to 035....and got to 1346hp at the crank... (in increments, they did a bunch of dyno pools )...they broke a push-rod due to valve float....so in essence, cast bottom end can go that high (that was a junkyard motor with over 100k miles I believe), I'd suspect the forged LS9 could go there too while offering a bit more reliability (per say)...though the 5.3 and 6.0 are iron blocks...
Been researching the topic for my current project and it's just amazing...

ace32x

An engine dyno and a loaded/weighted street car are a lot different though. Local guy has a gen 4 5.3 that let go at 900 wheel after a couple months.

TWS Racing

We have a local shop owner with a '96 ext cab Silverado, known as "The Red Sled". For a good long while the set up was a stock 5.3 swap with twin turbos. Est. about 1200 wheel. He would bend a rod every few weeks, but would just slap a replacement one in it and keep on rollin. This happened probably about 6-8 times. Eventually Jon got tired of replacing stock rods and bought forged rods and pistons, but that stock bottom end 5.3 held up a lot better than anyone would have believed.

DANZGLASS

pretty sure it let go due to the meth not spraying.