ddl6289

Last fall we bought an used 2002 Z06 with a Lamar Walden Automotive LS6 383 stroker with all forged internals (450rwhp/450rwtq). On Weds (4/26) the engine grenaded and puked its bottom end at the track (Blackhawk Farms) on the 2nd lap. Time for a new engine. I'm thinking of getting a GM crate LS6 long block (12498399). Does anybody have experience with this one? Also I could have DRM or Lingenfelter build an engine. I'm most interested in durability. The car is used almost exclusively for HPDE. Horsepower is not a priority. What can be done to the Stock LS6 long block to increase its durability.

Any and all advice appreciated.

Dan

ghoffman

Get an LS-7, and just do headers and a tune. With the dry sump you don't worry about sloshing. It is very reliable and you will be amazed how strong they are. My dealer said $13K complete except for the dry sump tank.

AU N EGL

Best bang for the Buck is the LS7. By the time you spend on getting an LS6 long block and building it up for relabilty you are almost at the LS7 price.

Red Gump

are conversion kits available for the ls7 yet?

varkwso

You can buy used low mile LS6/2 engines at multiple places and prices.

There are many crate engine options available - new from Chevy and many aftermarket sources. I would stick to near stock for HPDE or even some race classes.

Rebuilding your LS6 is not the cheapest option. I would keep it in the garage if it is numbers correct though.

LS7 is a conversion - LS2/6 is a swap......

ddl6289

Guys,

thanks for the advice. Just answer this one question for me:

Is a stock LS6 stout enough to handle the rigors of HPDE? If not, what are its weaknesses and their remedy.

Dan

XPC5R

Bang for the buck, start with an LS2 crate motor (around $6-7k I think) You should be able to buy the 2005 version that shares the same 36 tooth crank sensor wheel as the LS6. They don't really cost anymore than the LS6's do, but have a few extra cubes.

LS7's and later LS2's went to a 58 tooth crank wheel, which will require a different computer to run (reprogramming is not a workable option yet). Adding the computer, new engine harness, dry sump tanks, etc, may be more cost and headache than you want - but it can be done.

For durability, the oiling system is where the attention needs to be focused. Adding an oil cooler (standalone or integrated into a new radiator) and an accusump oil accumulator to help with starvation will take care of most issues.

After that, reuse the headers and intake you have, get a good ECM tune, and run for a long time at around 400rwhp, 380-390 rwtq. Add a cam later if you want more power.

ddl6289

thanks for your input. What are the advantages of an LS2 over an LS6?

XPC5R

LS2 uses the LS6 heads (but no hollow stem valves), but has a 4" bore block vs. 3.898". Stroke is the same, and they come with the 2001 Z06 cam. The biggest gain is the extra 20 cubes or so, for no extra cost. Also, the 4" bore opens the door for better flowing heads later.

redvetracr

Someone somewhere posted a link to (I think) Katech who had a bunch of stuff for sale....although I do know where there is a like new (100 miles) 18* 410" SB....turned a 2:25.0 lap in a C-3 vintage racer last Sept at Road America.....and thats without pushing the pedal all the way down from the "kink" to corner 12.....
...redvetracr

95jersey

yeah but what about the tranny and rear. The new Z06 comes with a pretty beefed up drivetrain compared to the previous Z06.

I would find a used one in a junk yard for cheap and throw in a G5X3 and some ported heads and you off and running with 450rwhp and you didn't break the bank. I would bet this whole package could be gotten for under $5000 EASY. You could go through (2) LS6's and still be ahead of the game compared to an LS7 with similar power.

But I am a cheap bastard, so it depends on how much $$$$ you have

ghoffman

Perhaps, but you still need a dry sump to do it correctly, so add $$$ and complexity. Accusumps and "add a quart extra" is a kludge. I have driven what you mentioned and it is not in the same league.

ddl6289

I want a reliable engine. One that can run between 5000 rpm and the redline, 20 to 25 minutes at a time 4 times a day. We do 18 to 24 HDPE days a year (it's my wife car) and I would like the engine to last at least 4 years. Am I asking too much? Again hp is not priority.

John Shiels

Depends on what you want to spend you could have someone build a LS2 stroker 402" with forged internals. It's all about money. You would not have the conversion problems. Call DRM and discuss it.

ddl6289

I had a big buck, all forged internal, 383 stroker LS6 and it blew up. My questions are this:

1) How long should a big buck, all-forged internals, LSx motor last? 25 HPDE days? 50? 100?
2) How long should a stock LSx motor last? 25 HPDE days? 50? 100? more?

My benchmark is the engine in my car, a 2003 Mustang Cobra (the Z06 is my wife's car). I'm putting down 450 rwhp. I've done 2 complete years (>50 HDPE days) on this motor and its as strong as ever (knock on wood). I'm wondering whether LSx motors are inherently less stable or my "accident" was a freakish occurrence?

John Shiels

After popping my motor a few years ago after 55,000 miles on it I put in a LS6 crate motor with heads & cam 450 / 400. I have about 5-6,000 mostly track miles on it. I put in new springs last year. It has DRM coolers and has run fine. I run it HARD and keep it in the upper rpm ranges most of the time. I think a good motor should last a long time with some freshening up on certain componets. You then have the fact of how it is shifted or a bad shift and to many rpms and it's gone no matter who build it. Probably make something next year with the best possible components if I feel like spending money. Mine has served me well so far. Hope I didn't just jinks myself

My original motor had at least 70 track or even more and beat to hell every second with no coolers I had no complaints. I watch the video as it ws still on when I opened the hood. I didn't even curse or complain it was do.

varkwso

I have a stock 2002 ZO6 - many, many HPDEs - 32,000 miles total. No problems with reliability or power so far ( I would like more HP - I do not NEED more HP).

I have a stock 1999 FRC - 120,000+ and the orginal owner was a HPDE instructor and has many, many more track miles on it. It still runs great and could use more HP - but the nut behind the wheel is still the slowest component - it is our primary track car now. I will run the engine to expiration and then replace with a stock LS6/2.

My wife has a stock 2005 GTO, 8000 miles, one HPDE......

2001 Cobra ventilated a block at Sebring last weekend by the way

The LS series is a good engine in my experience. Keep it stock and it is reliable.

ddl6289

Based on all of your input I now have more confidence in the longevity of the LSx motor. I think I'll go with the crate LS6 long block and bolt my intake and headers to it.

Any longevity upgrades to the crate motor before the installation, such as oil pump, or timing chain or valve springs, or rod bolts, etc???

thanks again

AU N EGL

only if plan on putting a different cam in there. I would also put on that 500+ miles to break the motor in.

Good Luck

larryfs

some of the T1 guys sell there used motors. many are still good, but they just like to replace them.