Oldsmobility85

iTrader: (1)

Had a question about some carbon/soot buildup in the intake ports of my heads.

First off the engine is a 96-00 vortec truck engine with ported factory cast heads milled to 57cc chambers. 2.02 1.60 ferrea valves comp 950 springs retainers all that good junk. Has 1.6 rockers on intake and exhaust.

Camshaft is a comp custom grind 535 lift 224 duration on a 113lsa degreed in at 110* intake center line.

Engine had roughly 1500 to 2000 miles on it and spun a main bearing due to oil starvation. motor went 8.36 in a 96 firebird with 4.10s et streets and 3400 stall. Went 7.84 on a 100 shot. Engine had 32* of timing on motor and spray and a 10.5 to 11.0 Air Fuel Ratio due to warmer weather. (was dead on last winter).

Anyhow I decided to junk the motor and build a nice 406 to go faster and after taking the intake off this motor realized the soot buildup and I ported and assembled this engine myself they looked as good as polished iron can look apon assembly.

Any Ideas??

BAMF

poor valve seal? that's strange ah.

Oldsmobility85

iTrader: (1)

No not on every cylinder I wouldn't think. I think it is more of a valve timing cam grind type of situation. IDK. I really don't think its a problem at all just wondering if anyone had some info that could more pinpoint the cause.

dnkynrbk

iTrader: (34)

Does it still have the EGR hook up? Are the rings gapp for nitrous if so a oil catch can linked between the valve cover and intake. I had to my 408 rings are gapped for a 300 shot so I was getting blow by in my intake and in my heads.

Oldsmobility85

iTrader: (1)

No I was just running out of the box hastings low tension ductile iron rings with a standard bore. (not filefit) and I don't run pcv valves or fresh air systems. I just use a push in breather on one side and a evac system to the other valve cover. Only thing I like through my intake is air, fuel, and spray. LOL.