5.0 85 GT

hey guys, my cobra has a fully rebuilt drivetrain with about 2k miles on it....everythign had new lifters/lash things gasktes seals etc bored 30 over....i got a SCT XCAL SF3 tuner and just did my own 93 perf. tune on it....car ran much better but sometimes she blows white smoke out the back under WOT, and occasionaly when i start it, depends on the day....i no of a lot of cobras that blow smoke at start up but i dont see alot blow it out under WOT, like i can hammer it in first and take it to 100 and no smoke at all, then i can drop it down again and i will have smoke come out....

i dont understand it..it does not leak one drop of oil...engine bay is super clean, any suggestions? if osmething serious then i have 1yr warranty on motor to get it fixed...so let me know...thanks

1999 GT

bump.. anyone..help him out

5.0 85 GT

anybody got anything????????

OzzDOA

I'm no expert but a .030 overbore is too much on a 4V mod motor. I wouldn't be surprised if you don't have perfect seals with your head gaskets and that is why you are having smoking.

Smokin04

Its hard to say why bro. When you can't be there to look at it, it's even more difficult to diagnose. White smoke usually means a coolant or water in the chamber issue, where as black smoke can be a rich mixture, etc...and blue-ish smoke usually signifies oil is being burned somehow.

I agree that a 30 over is a bit big for a mod motor. It can be done successfully, but which block you have will make a difference.

Do you have a wideband in the car or have a friend that has one you can use to see if it's a rich mixture? That would kill one possibility.

I don't think it's an oil issue because it's a fresh motor...BUT the rings might not have seated yet, which could be causing the smoking. How many miles did you put on it before whacking on it? And what kind of PCV/Breather system are you running?

5.0 85 GT

ok...the car has about 2600 on the motor now, it wasnt opened up by me untill the 1200 mile mark...the guy before me owned a machine shop and did a mint *** job on it....he beat it with about 800 on it....and i just found out today that the white smoke wasnt white smoke......i finallly asked my buddys and they said everytime i gas it like on an onramp its black smoke....so that means its running rich right? i am going to get ti tuned but after i get a TB on it......i think i have a vid on utube of it doing that....ill c if i can post it on here

5.0 85 GT

http://www.youtube.com/watch?v=7Lh6GoHF3q0

there is the vid...welp now tha ti see all that carbon black **** i feel liek an idiot....feel free to watch my other vids...did osme stuff in my old gt...

OzzDOA

Yup the thing is running pig rich, probably somewhere in the 10.5 or 11.0 area.