39 replies to this topic

[turbotrana]

Blueprint or clearance the pump and you will get enough at idle to not be a problem

[greens nice]

^^^+3.

Be careful using a high volume oil pump if you don't have an increased capacity sump.
Don't know how true this is, I've heard stories about all the oil being pumped up to the top of the engine at high revs and not much left in the sump so the bottom end gets starved.
Can anyone with 1st hand experience confirm.

Done plenty of hard revving in a 186 and never ran out of oil, from memory yella Tella head ( which I had )they drilled out the return diagonal holes. ( in the line of the rocker posts ).

There may also be a myth associated with this aspect also, the reason I say this is because the 202 heads have at least double the return rate as the adjustable type heads.

So I gather if there are sometimes problems it would only be in the pre 1972 era 6cyl engines and XU-1 engines, also a engine with sludge forming would have returns starting to retrict the return flow too.

A normal 202 head 2811930 has clearance on the push rod holes ( all 12 of them ) this in addition to the earlier type return holes which were still drilled diagonally through.

Early 138, 161, 179,186 and XU-1 heads had special flat sidded broached holes that were guides for the push rods, this is why there is always shiny marks on the push rods on these engines.
While these broached holes do have clearance in one plane, the back and front are a close fit and minimal oil would return past the push rods, except for the diagonal holes drilled which lead into the push rod holes further down than the push rod guides.
These heads have three or four return holes plus what ever can escape through the restrictive push rod holes, this will be minimal in a cold engine I suppose.

Mike

send a drill down the pushrod tube and get rid of the flat sided holes and use guideplates.
to Spack,

ive drilled the tubes, deburred the head, i didnt drill the drain holes out that are next to the rocker post, but i smoothed the outside of them and the large drop leading to the hole inbetween the rockers posts i smoothed etc. i smoothed the edge's and made a radius on the drain holes between the lifters and also send a drill through and radius the hole that goes from behind the sideplates to above the timing gear. just the small things that add up but you have probably already done most of this.

with an EH Sump with standard capacity and hpr30 penrite oil & yes it has a hv pump, it still has oil pressure at the other end of the strip, crosses the line at 6200.

cheers

[orangeLJ]

My 202 sits at basically nothing when got (mechanical automater procomp gauge)

But has plenty once revs climb.

I used to stress, now... Honestly I don't GAF

Last engine was similar, when I pulled it down, it was perfect inside, no excess wear, bearing nice etc etc.

If it pops from idling with no oil pressure when hot, then it was always going to pop at some stage anyway