AU N EGL

Ok all you hot shoes

How often do you rebuild your track engine?

and do you think this contributes to engines blowing up on track and oil spills?

Cobra4B

My racecar started life as as clean street car with 119,xxx miles on it.


I've been W2W racing and TimeTrialing my it for two years w/o issue; been tracking C5s for 10 years now. The car has a LS4 high volume pump (42 psi relief spring) and a DRM oil cooler kit with a Setrab cooler. No accusump, no drysump. The longblock is the original one it came with in 2001 with over 122,000 miles on it now. The last 3k all track use and it still made 365 rwhp when I had my NASA dyno certification done this February. The car's only power mods are a Halltech filter replacing the stock airbox, the ATI damper, and a cat delete on the stock H-pipe. In prepping the car I simply installed the following:

1. Fresh LS6 springs
2. Lower mileage rocker arms
3. Lower mileage injectors
4. Fresh LS2 timing chain
5. 10% underdriven ATI superdamper
6. DRM oil cooler kit

Full build of the car can be seen HERE

So my answer = When it eventually blows up or starts making noticeably less power. I do plan on replacing the valve springs in the off-season this year with another set of new OEM "yellows".

~Brian

CHJ In Virginia

After 6 years of tracking the car hard, 10-12 events a year, have never had to do a total rebuild. ( Knock on wood) Just refresh the valve springs every other year, change oil every third event. LS6 has been basically bullitt proof.

Short-Throw

Tom,

This is a great topic and should be interesting but:

this specific question covers many broad uses (racing, HPDE, etc) from the forum members here and will yield many responses from the various applications.

Secondly, I highly doubt all drivers perform the same maintenance and many are probably unaware of what really should be done and learn the hard way after a huge expense. Some drivers are extremely fast without banging the rev limiter every upshift, while others are slow and feel redline is the place to be perpetually.

A good question is: How many keep a log book of actual engine hours? Most just look at the odometer, that's not very helpful.

Lastly, add in the plethora of different setups ranging from bone stock cars, bone stock engines with chassis mods, to full blown race cars and the permutations escalate.

Note: Engines blowing are prevalent across all manufacturers. I saw 2 Porsche's (was only there for 2 hours of a 3 day event so there most likely were more) towed in with blown motors at the event prior to VIR. Audi and BMW events have the same fun as well.

Heroin or Yachting are cheaper to finance.




Mike

topmover

I've come to the conclusion that on a big HP built motor that 20 hours is when one should consider a rebuild. That is when I plan on doing my built 427.

Many here have a lot of experiance with stockers so I think a lot of data must exist on those.

I took a lot of flack on the ZR1 site when I said that I'd question if GM would warrentee a LS9 if it broke with 50 track hours.....my opinion was that is asking a lot of the engine making that much HP.

geerookie

They are "Blue's" now.

redtopz

Run it hard until it blows (stock ls6). I'm still running my original 2004 ls6 with probably over 10,000 track miles on it. And it still puts out enough power to require me to run a restrictor in ST2! Although I think that dyno might have been a little generous.

The cts-v ls6 crate engine I put in my T1 car last year was a total piece of garbage however. Only lasted about 6 track weekends before seizing up on the bottom end. Also had tons of blowby and made crappy power. I just installed another crate engine in that car last month, but went with a 2001 corvette ls6 crate engine that came with a new oil pan and water pump. I swapped in the 2002 cam and heads from my old engine. This one seems to run better so far on the street. I'll find out how it does at the track next weekend in Sonoma.

redtopz

I just installed new yellows last month on my 2002 243 heads. I thought the blues were for the 2001 heads?

Cobra4B

I think there are the older 2001 springs that are a darker blue. The "new" LS3 spring is a bright royal blue if sorts. Has that replaced the '02-'04 Z06 "yellows"?

geerookie

Here's the current part number from the GMPP Catalog and a picture of the springs.
12499224 LS valve Spring kit

• Beehive style springs

• Used on LS2/LS6 cylinder heads

• 1.800" installed height @ 90 lbs. pressure

• Max lift .570"

• 1.250" @ 295 lbs. pressure

• Includes 16 of P/N 12586484

Cobra4B

Yeah it looks like these have replaced "yellows"... at least on Scoggin-Dicky's website. I'm curious if they're the same specs as the "yellows". From what I remember the '02-'04 springs were slightly stiffer than the 2001 springs, but that could have simply been forum hearsay.

geerookie

You are correct.
In '01 and '02 - '04 the closed loads are the same–400 Newtons (90lbs) on
the seat but the open loads on the nose increase from 1150N
(259lbs) to 1310N (294lbs) for '02 - '04.

SteveDoten

c'mon, let's not turn this into a c5gen 'tangent' thread , cool thread btw.

springs; both are in current GM supply(speculation), I'm getting the blue one's Brian posted lately for OEM LS6 replacement (rash of about 100-300 cars that have failed springs)

/on topic.

isnider

That's the beauty of a factory 5yr/100,000 warranty

People spend tons of money "building motors", the ZR1 motor is hard to beat for the money....

Ian

John Shiels

yea but most won't want to trash a car that's over 100 grand

AU N EGL

We had an LS9 let go this past weekend with 33,000 miles and a LS7 with 38,000 miles blew a rod out the block side, and dumped oil down the front straight. Two cars went spinning off track do to the oil too.

topmover

I'd be curious to know more about the LS9 that failed, as near as I can tell very few people track them and some that do dont push them. I'm guessing that it was someone who doesnt post on the ZR1 site as only about five or six guys on that site seem to have any interest in road racing and there has been no mention of it over there.

Do you happen to know anything about the car like miles and track frequency?

AU N EGL

it is an almost track only car. most likely Blew a rod but it did not come though the block.

Also he put in BIGGER radiator the stock GM one where not good enough to keep temps down.

AU N EGL

This is the reason I posted this question:

http://forums.corvetteforum.com/1581189618-post232.html


It seems that too many guys are waiting for their engine to blow up and risk the oil on track and cars spinning, vs 30-35 hour maintenance rebuilds.

topmover

It will be interesting to see if GM covers the car both because of track use but also the larger radiator(mod). As I've experianced some heat issues on long runs I've wanted to make a few changes like water wetter better oil etc. but havent due to warrentee concerns.

I know budget is an issue with everyone and many on this site talk about safety but one of the last things I want is oil on my tires at high speed.

There is a reason that fast drag car have to have dipers.