ok running a ttrim on a 94 LT1, 7psi, motor is cammed, ported heads. stock pistons ruffly 100k on them. just added water/meth injection over the weekend from snow performance, stage 3 kit. so took it out and ran it for maybe 10mins, got on it 3-4times for quick bursts just to hit like 2-3psi to kick on the kit , after running it i now have oil puffing out the breather on the VC its not real bad but noticeable when idling. car still drives fine and feels strong, oil psi is great, vac at idle is like 14-15in/hg?? burnt valve or rings going?

 

Good amount of power on a stock motor. If its just a little, don't panic about it but be aware that it will eventually let go. But it may have years left in it now.

I ran a big ring gap on my n20 motor, and even bigger on my boost motor. I get little puffs myself on a new motor. Most likely related to rings though.

If it starts pouring smoke you know its time to tear it apart.

 

sounds like you broke a compression ring or a piston is starting to crack. i bet if you do a leakdown test youll find a cylinder with leakage. happened to me when an injector went bad and the cylinder leaned out. stock ring gaps are only like .010-.016". if they get hot enough theylll expand and butt up or try to lock up in the bore and break. chances are youll be tearing it apart soon in my opinion. when you get on it now, youll most likely start blowing the oil dipstick out of the tube under boost. boost on high power stock bottoms is tricky, doesnt take much to hurt the piston/rings unfortunately.

 

yeah something broke or gave on it. 2 factors that could of done it in are the water/meth kit or fresh royal purple 5w30 syhtetic oil. the water/meth kit literally only sprayed 2-3 psi of boost at like 40% flow, my tank is still filled to the top pretty much so that says how much actually got sprayed. think i should run a thicker oil until i can get it in to get rebuilt? some 20w 50? or...

 

depends how bad the pressure is coming out of the filler neck. i could hold my hand over it and it would build pressure in the crankcase pretty quickly, so i stopped driving it for the time being. if you stay out of boost and its not real bad, you could get by for awhile, but yer gonna start pushing out seals and gaskets if its really huffin.

 

well if it was real bad would i be losing oil psi or would i start getting real low vac #'s at idle? rite now like i said im getting 25psi at idle and it gets up into the 60's @ WOT. vac is like 12-14 @ idle

 

vac will be a tad low because you're losing engine efficiency with the damaged piston/ring. oil press. will not change, problem is you're getting combustion gasses into the bottom of the engine

 

yeah im just gonna take it to the shop and have them rebuild it with forged internals then before i really break something

 

Ya, I went 383ci all quality forged internals... (Calies, Eagle H-beam, JE 2618). A Procharge D1 pulley to 15psi. Still blowby. FI always has blowby. Oil control for FI is always a problem when the PCV system is design for NA. I tried all the tricks used on this web site. None worked for me to my satisfaction. So, I engineered my own extenal VAC system for the street. Now, I have oil control, no rear/ front seal leaks, and massive cylinder pressure which results in massive torque with instant application. It is a whole new car. But, just my experience. I have not seen a 4th Gen LT1 with a crank driven street driver with an external VAC pump system. HTH. B.