1 2
Keith
Keith GRM+ Memberand SuperDork
11/19/11 1:43 p.m.

GM knows how to make it work, obviously. The Le Mans Corvettes are taking far more abuse than trackway cars.

The_Jed
The_Jed Reader
11/19/11 2:02 p.m.

So should I put some baffles in the Burban's (LM7) oil pan?

Greg Voth
Greg Voth HalfDork
11/19/11 3:54 p.m.
docwyte wrote: Campaigned my LS1 equipped 951 all season with no issues. 4 30 minute sessions a day, 6+ weekends...

I hear about 5.0's blowing up as well but our car has lasted two lemons endurance races 24 and 14 hours respectively (probably about 30 hours of time on track) without issue. Just keeping it 1 quart of oil above full.

I think it depends on how many G's the car is pulling, what track and turn they are on etc. I am putting an LS1 in my 1st gen RX-7 and doubt I'll be pulling the G's these Corvette guys on slicks do. 315+ width tires generate alot of grip.

camaroz1985
camaroz1985 Reader
11/21/11 9:31 a.m.

We are adding an extra qt to our 5.0 for the next Lemons race. We noticed the pressure dropping in corners this past one.

carguy123
carguy123 SuperDork
11/21/11 9:32 a.m.
Keith wrote: GM knows how to make it work, obviously. The Le Mans Corvettes are taking far more abuse than trackway cars.

So GM is running LS2s or 3s?

The problem is supposed to have been fixed in other versions.

Keith
Keith GRM+ Memberand SuperDork
11/21/11 9:51 a.m.

The Le Mans Corvettes run the LS7.R. You can probably guess what it's most closely related to. And like the street LS7, it's dry sumped. Possibly with a bigger tank or more scavenge stages, I don't know.

It's a Gen IV engine, just like the LS2 and LS3. The LS1 and LS6 are Gen III - I mistakenly referred to these as 4 and 5 in an earlier post. I don't know if the generational change is significant, but it does seem like more than a coincidink. Remember that the LS3 is the current production engine while the LS2 has been replaced, so anything that was "fixed" in the LS2 should also have carried through to the LS3.

After having a bit more time to go through the entire thread, it appears that it's only the serious racers that are having trouble. Sustained 1.2g or more on a left turn. That should give some big clues as to exactly what's going on.

bluej
bluej Dork
11/21/11 11:58 a.m.

I don't have anything constructive to add other that someone needs to TM "LSJohn" and sell them with the grills and margherita makers.

turboswede
turboswede GRM+ Memberand SuperDork
11/21/11 12:48 p.m.

Not sure what's running in this:

https://www.facebook.com/video/video.php?v=2052598753300

http://www.youtube.com/watch?v=HPHmOIjjlwI

but it appears to have had an unknown issue and blown up:

http://forums.corvetteforum.com/garage/2005-Chevrolet-Corvette-4051-OCCOMSRAZOR.html

http://forums.corvetteforum.com/c6-tech-performance/2944036-need-opinions-on-new-road-race-motor-build.html

So its an LS2 from the above specs. Still, those vettes can generate a ton of lateral G's.

Varkwso
Varkwso HalfDork
11/23/11 7:57 a.m.

The problem is pretty much limited to the LS3. The LS1/2/6 are ok with the batwing pan LS6 being the most reliable (and no longer available in a crate). The LS3 Grand Sport Coupe comes with dry sump. Those run 335s by the way.

Early LS7s also tend to detonate in an impressive manner and they are all dry sumped. The 08 and later dry sumps are better.

Canute
Canute New Reader
11/23/11 5:20 p.m.

Thanks for that information. I knew I wanted a C5 Z06 for some reason.

fasted58
fasted58 SuperDork
11/23/11 5:48 p.m.

2010 Chevy Corvette Grand Sport LS3 dry sump lubrication system explained

http://www.youtube.com/watch?v=8YzY8DhlnUw

Javelin
Javelin GRM+ Memberand SuperDork
11/23/11 5:55 p.m.
docwyte wrote: Campaigned my LS1 equipped 951 all season with no issues. 4 30 minute sessions a day, 6+ weekends...

As I understand the issue, which isn't well, it's a drainback issue with the Gen IV square-port engines (LS2, LS3) that wasn't an issue with the cathedral-port Gen III (LS1, LS6). I could be totally wrong though as there's a distinct lack of LSx anywhere on my property...

1 2

You'll need to log in to post.

Our Preferred Partners
HkRl5OKlkd0oNrrFoSOxUlfuKC50dhEEObXjb61KoYdbgjyuzAa8uONJ6BiFYtiD