Small Port Oil Drain

Alex170984
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Small Port Oil Drain

Postby Alex170984 » Tue Nov 29, 2016 1:52 am

Hi,

I have the small port cylinder head with the oil drain.

I am using a 3-rib block which does not have the inlet for the drain.

If I was to re-route the drain from the head to the sump, will it be better than blocking it off completely?

Cheers

totta crolla
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Re: Small Port Oil Drain

Postby totta crolla » Tue Nov 29, 2016 3:17 am

A simple 'thank you' now and again goes a long way you know...

Alex170984
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Re: Small Port Oil Drain

Postby Alex170984 » Tue Nov 29, 2016 3:21 am

"cheers!" in British English Dictionary.

used to mean "thank you"

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ToeKnee805
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Re: Small Port Oil Drain

Postby ToeKnee805 » Wed Nov 30, 2016 12:41 am

DO NOT quote me on this: but i believe the oil drain was only on the high compression blocks/heads because the crankcase pressure wouldn't let the oil correctly drain out the head like the largeport setups. So if youre running a largeport block you shouldnt have that issue if you just block it off. Im currently running the opposite (High Comp block, with Largeport head) and for the longest time I was running a plug where the hole for the drain is. Currently I have my catch can draining onto the hole in the sump.
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust

Alex170984
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Re: Small Port Oil Drain

Postby Alex170984 » Wed Nov 30, 2016 1:43 am

In terms of the high comp block, I am using the high comp pistons...and the compression will be loads more than standard 10.3

Does that alter things?

Thank you in advance

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Rogue-AE95
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Re: Small Port Oil Drain

Postby Rogue-AE95 » Wed Nov 30, 2016 4:45 am

I thought the head & block drain was mostly because of a FWD setup, which was the only way hi-comps were available from Toyota. When making a hard right(?) turn in a FWD, the oil would pool into that end of the head, so the drain helped move the pooled oil back into the oil pan to prevent oil starvation.
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Deuce Cam
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Re: Small Port Oil Drain

Postby Deuce Cam » Wed Nov 30, 2016 7:10 am

It will be best to run a line to the sump for a drain. Even in rwd layout it doesn't drain enough when the roads start to get twisty. Ost even offers a service to add a drain to the largeport head in the same spot.

I speak from experience. On my stock engined gts I was burning at least 1 qt. oil between changes when I lived in SC (I drove on really windy mountain roads most of the time - no grid there). Otoh when driving 100% grid in PHX I never burn any oil between changes.

Another option is running a custom breather setup and/or an air/oil separator to prevent the pooled oil from getting pushed to the intake on left turns.

Alex170984
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Re: Small Port Oil Drain

Postby Alex170984 » Wed Nov 30, 2016 7:35 am

Hi,

Thank you for your informative replies :)

I'll modify my sump so that I can make a custom setup to drain back into it.

SgtRauksauff
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Re: Small Port Oil Drain

Postby SgtRauksauff » Wed Nov 30, 2016 8:44 am

My thought, which I've never acted on yet, was to make a hole in the back of the head, just flush with the 'floor' of where the oil would sit, something like an AN-12 or -16 size, maybe even a -8/-10 if one for each bank of valves, and use some hoses or hardlines to drain right to the sump. This would allow the longitudinally mounted engine to drain via gravity like it should in a Correct-Wheel-Drive application.

I've had a few occasions on track days (turn 4 and 5 at BlackHawk Farms for sure) where extended-length left turns starts me cropdusting, and I get a meatball flag to get off the track, ruining my times. A catch-can is a good stopgap fix, but I'd rather be able to do away with the catchcan and not need to top up the oil as often.