smurfman

iTrader: (3)

I just got my 1 X 3/4 Kooks LT Headers installed along with the Catted Y-Pipe. I do not have the exhaust hooked up. There is a lot of popping when you take your foot off the gas or downshift and let the car slow itself down. It does not feel like it is missing at all. I also removed all emissions (AIR & EGR). I also put in NGK TR6 spark plugs gapped at a lil over .35.(nitrous waiting to be installed).

Maybe this is normal. I do not know.

There is also alot of vibration in the shifter...I am guessing this is b/c I do not have the exhaust hooked up, and it is causing a lot of vibration under the car..if this is normal, please let me know.

Thanks for any help.

greentahoe

iTrader: (2)

My truck has done the same thing since the headers. I think it is running rich, but havent had a chance to re check the AFR.

Hellion

Right after I installed my headers my car popped (back fired) with the open headers, but my car was also missfiring because one of the spark plugs was cracked. Not sure if this helps or not. Do you have your front O2 sensors pluged in? Also, does your SES light flash at all, or does it just stay on (of course assuming that you have not deleted all of your SES codes...). If it flashes when you get on it, (if I remember correctly) that means that your car is missfiring--So, I would check the plugs and wires...

Hope that helps some

smurfman

iTrader: (3)

Yes I have the o2's in on the headers and on the Y pipe. I only drove the car for maybe 2 miles, maybe it just needs to warm up. It seems like if a spark plug was missing it seems like I should feel a loss in fire, or feel a sputter, and I do not feel either. Maybe this is normal...I do not know.

TurboMinivan

I'd wager heavily that it's normal. I'm new to V8s but not to big exhausts; I've got a full 3" mandrel system (with Dynomax straight-through perf core "bullet" muffler) under my Caravan, and it pops and crackles at high vacuum much like you describe. These noises occured when the car was stock; you just couldn't hear them thanks to the OEM exhaust system doing what it was designed to do.

BTW: a stick shift will exaggerate these noises based on my experience with 3" mandrel exhausts on a variety of my own cars.

smokin' joe 00 ss

Thats normal with open headers it's just the cold air being suck it when you back off the throttle and when the cold air mixes with the hot air and hot headers it will cause it to pop.

smurfman

iTrader: (3)

Thanks for your replies guys. It is always reassuring to have other peoples opinions. I will be throwing her on the dyno soon enough, I will post results.