Z06 4 Me

Hi Everyone,
I have a question for you tech guys. I went to look at a vette that I am thinking of buying.
It has a ls6 that is bored and stroked to a 440ci. It has a breather filter mounted on the oil filler cap. When the car was sitting there idling a noticeable amount of vapors were coming out of
that filter. Is that normal?
Thanks for you help!

bucketlist1957

You should not see smoke coming out of the breather! Just my opinion. A lot of high HP motors even require additional vaccum besides the PCV system to keep the crank case pressure nuteral. It could also indicate another more serious problem. The reason I under lined my opinion is there are several people on hear think you don't need PCV and valve cover vents are all that is required.

NassyVette

It's not uncommon for highly modified cars to run tubes from the breathers to the header collector for crankcase ventilation. The downside for street cars is inadequate venturi effect at idle, fumes, smoke and legality.

Long story short, if it's blowing vapor out the breather it's likely just an indication of improper baffling under the breather. The lack of a proper pcv setup can be seen as an indication that other areas were patched over as well. Inspect the rest of the car closely.

lucky131969

No offense, but if you have to ask a question like this, then chances are, you many not be able to evaluate what has been done to a modified engine. See if you can team up with a local forum member, who is knowledgeable in modded C5's, so they can point out potential pitfalls, poor workmanship, etc.....or.....see if the owner will agree to have the car inspected at a corvette shop of your choice.

Good luck.

kp1

No it isn't normal in my opinion either. If there's that much positive crankcase pressure at idle, something ain't right.

I guess I haven't been paying attention. When did people start getting 440CID out of an LS6? Resleeve?

rboineau

Run away. . . . run away. . . .

ztheusa

It is just an indication that SOME IDIOT has modified the car.

Jnape

Yes resleeved. A 4.125 bore w 4.00 stroke is a 427. so it has been bored probably to the max of the sleeve. A tall deck block can get 500+ ci in what is still a small block engine.

Bill Curlee

RUN FOREST!!! RUN!!




Here,,,, READ THIS POST!!

http://forums.corvetteforum.com/c5-t...is-normal.html

BigGun

See post #4. You could have a jewel or a turd. The key words are, "who is knowledgeable in modded C5's, so they can point out potential pitfalls, poor workmanship, etc..."

Bill Curlee

I agree. You either have a damaged/ defective or NON Functioning PCV System OR the ring blow by is FAR GREATER than it is suppose to be which overcomes the PCV system or BOTH.

Get someone that is well versed in LS Engines who has ZERO emotional stake in the car to evaluate and report the source of the issue.

Bill