I have a mark 5 bbc completely rebuilt. I used a factory roller cam for a 98 mark 6 and comp cam retro fit hyd roller lifters. my problem is I cant get the intake lifters to quite down so I tryed adjusting them hot engine running. This is when I disscoverd that the intakes have harly any oil coming out compared to the exhust. Any ideas what would cause this I am at a loss. I have driven it about 10 miles to see if the lifters would pump up with no luck.

1.check oil pressure.

2.check orientation of the lifter oil feed holes.

3. if you have the net lash type valve train, you cant really adjust them.... but, if you have the old style rocker arms and stuff, you should be able to.... so... Check your pushrods to see if the oil feed hole is coming close to the bleed hole in the rocker arms

1.check oil pressure.

2.check orientation of the lifter oil feed holes.

3. if you have the net lash type valve train, you cant really adjust them.... but, if you have the old style rocker arms and stuff, you should be able to.... so... Check your pushrods to see if the oil feed hole is coming close to the bleed hole in the rocker arms

#1 idle 35 lbs
#2 they are fixed with the rod between the intake and exhust lifters how can you change this
#3 old style adjustable comp cam roller tip rockers..... just a small amount of oil coming out of hole in rocker on the intake only....exhust is shooting oil out????

sounds like the lifters arent getting oil to the feed hole.

Is this Joe?

It is realy strange that your exhaust lifters seem to be getting oil and the intake ones are not??? Is it the same on both sides, I thought each side was fed from a common oil line?

New oil pump? How did you set up the pump? Low pressure/hi flow or the opposite?

Its on Joe's dads truck. He got ahold of comp cams this morning and they are sending him longer push rods to fix it.

how are longer pushrods going to fix a oiling problem?

How much is it going to affect your lift ratio?

Push rod length effects ratio?

there are two different pushrod lengths in bbc's.

exhaust and intake.
edit! the ratio may NOT be affected, but overall lift will be

generally, most stock rebuilds wont need to worry about pushrod length differences. when using hydraulic roller lifters on a stock block like a gen5 bbc, you could need a .300 shorter pushrod than stock because the lifters are longer by .300 inches... unless you figured some magical way to get em to fit... if the lifters are the stock hydraulic lifters, they maybe a different length too.

and since the valve angles are different between exhaust and intake, there is a chance that the pushrod oil hole wont line up with the rocker arm oil hole and it wont produce oil to the rocker.

just observations. wasnt there to see the cause.


*when building a racing engine, you should probably make a great effort to get the best pushrod setup you can. pushrods that are the right length can add lift to a cams specs, as the cams are sometimes listed at less than actual height due to deflection, improper length pushrods, and other things like gasket thickness.

differences of .020 in pushrod length can make a difference in the lift of a cam on an engine. getting the right length can make 10 hp. all for the cost of a set of pushrods. *(which really isnt much)