70_Chevelle_

Has anyone ever run their LS1 with open exhaust manifolds? If so, how does it sound and does it do any damage to the surrounding area.

I need to break-in my new motor and I can't use my new headers for break-in.

Suggestions???

01ssreda4

iTrader: (96)

you cant run it with O2s in it or it will cause them to prematurely fail. If you must do this attach a length of pipe on the end so that it wont **** the O2s up. O, and it will sound like ***

01SOMZ28

iTrader: (37)

go ahead, if you like the grain truck sound!

70_Chevelle_

I know it will sound like crap...I have Hookers in the garage but they said you can't break in a motor otherwise it will mess with the curing of the ceramic coating.

How would you hookup the O2's?? Do I need to put bungs in the scrap extensions or can I rig it another way. This is all VERY temporary....

Xtreme864

iTrader: (15)

I'm not sure how valid the info is but i heard it is an easy way to bend a pushrod...

Mumbles

iTrader: (5)

If you still have your stock manifolds and Y-pipe, I would reinstall them for the break in period. I suppose you're running true duals and don't have a catback exhaust to attatch them to. If thats the case, I suppose you could run with just the open Y-pipe. I'm sure it would sound wonderful. *sarcasm* Unless you still also have your factory or any other catback that you could also reinstall for the time being. Thats all the ideas I have for you. I definitely wouldn't run open manifolds. Good luck.

hitmanws6

iTrader: (20)

if you want to ruin your brand new engine by doing this go right ahead

BlackScreaminMachine

iTrader: (17)

Put something in there. Assuming this is going into a 70 Chevelle, which I have owned, it has a decent engine bay but the manifolds exit is still in the engine bay. I do not know why it "needs" to be broken in now. Since your exhaust set up is not ready. You mention curing for the header but here is the deal with that.

The coating come off eventually, anyways. Whether the motor is ran for a short period or a long one, the coating will come off. So dont worry, just toss them on there.

Radcannon

iTrader: (3)

The coating will be get screwed. Breaking in a motor causes it to run hot with no air blowing over the headers, it will not hurt functionality but it will completely dull the shine. You pay for the shine and heat dissapiation characteristics. Why would your cut its life expectancy by breaking it in with them on listen to hooker.

Also how are you going to bend a valve I hear this all the time. The air is sitting stagnat how is cold air going to make it up to the valve immediately and quench it (at a very quick rate) to change material properties, especially considering hot air rises and its summer ambient temperatures aren't low and air is not a good conductor of heat, cold water thrown on a hot exh valve ok plausible. I call BS on anyone that says that. You can't be very famaliar with material properties to think this but prove me wrong if you know something I don't.

I ran with open manifolds no problem sounds like ****, but whatever. I didn't ruin my 02's it will be fine. 02's won't care and I am guessing when you do a tune anyway it will be a maf tune and wont use 02's. It will pop and backfire a little but unless you have a gas leak fine. The y pipe won't help much i was shooting flames out when i put my y-pipe too.

Headers or manifolds will be fine for break in. Look at the drag motors running 2000+ hp with a straight pipe pointing up from every exhaust por into the air probably 2 feet long or so and the heat rises right out when they shut those motors off. I have never heard of them breaking or bending valves, and I am sure their in cylinder pressures and temps are higher than your motor.