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Oil drain for twins

Old 06-10-2019, 01:12 PM
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Oil drain for twins

I was over in TallTims twin GT35 build asking about oil feed/drain lines as I'm in the middle of a similar build. I've figured out that I can use -4AN lines off a tee from the oil pressure fitting for the feeds. As for the drains, he used two -10AN lines into the fuel pump block off plate. I have a later ('96) block so no plate. Is the oil pan my only option? Can I run a y fitting into the pan from the two lines or will that back up? Or is there enough real estate to put two 1/2" holes above the drain plug. I'd prefer not to yank the motor but... Thanks.

Here's the work in progress:
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Old 06-10-2019, 02:15 PM
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Re: Oil drain for twins

I dont think that would have gravity drained to a plate to begin with atleast not the driver side turbo. Maybe but not ideal

You will want to drain to oil pan, ideally one per side. Or to a scavenge pump and pump to valve cover
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Old 06-10-2019, 03:48 PM
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Re: Oil drain for twins

Thanks, So I'll scrap the idea of running a two into one y fitting into the oil pan. I can't see much room on the passenger side ( to get a drill in there) but on the drivers' side of the pan it looks OK. Maybe a 90 degree drill. Just drill, tap and thread a fitting in. Sorry, that's a question, I've tapped other thicker stuff before but nothing as thin as a pan.
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Old 06-10-2019, 03:57 PM
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Re: Oil drain for twins

Fitting near front of pan may work with a 2 into 1 drain just make sure both are as downward an angle as possible.

I never tapped a pan lol just welded fittings
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Old 06-10-2019, 04:06 PM
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Re: Oil drain for twins

I like the welded fittings idea better but I take it that means pulling the pan...
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Old 06-11-2019, 06:58 AM
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Re: Oil drain for twins

Originally Posted by Orr89RocZ View Post
Fitting near front of pan may work with a 2 into 1 drain just make sure both are as downward an angle as possible.

I never tapped a pan lol just welded fittings
I have.. It's always a mess. I found on my 412 the fuel pump blockoff plate just didn't allow it to drain fast enough so it got backed up, so I had to stick a -10 fitting in the front of the pan.

Self contained turbos would be cool. I guess the packaging would be difficult.

-- Joe
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Old 06-11-2019, 07:16 AM
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Re: Oil drain for twins

So the consensus being drill and tap at your own risk. And don't complain when it leaks... For a car that gets so little mileage, I think I'll try that route for starters with the plan to put weld in bungs next time the engine comes out. And that'll be when I get brave and turn up the boost.
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Old 06-11-2019, 07:26 AM
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Re: Oil drain for twins

Originally Posted by brian p View Post
So the consensus being drill and tap at your own risk. And don't complain when it leaks... For a car that gets so little mileage, I think I'll try that route for starters with the plan to put weld in bungs next time the engine comes out. And that'll be when I get brave and turn up the boost.
Don't drill. Punch your hole so it rolls the sheet metal, which gives you enough material to tap. You start with a taper punch and then finish with a straight punch that's close to the OD of the drill bit you would normally use.

I used some 'right stuff' on the threads when inserting the NPT to -10 AN adapter.

I'm not that concerned about leaks as much as I am metal getting into the oil.

-- Joe
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Old 06-11-2019, 07:28 AM
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Re: Oil drain for twins

Yeah i was gonna say try right stuff to seal it or epoxy
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Old 06-11-2019, 08:42 AM
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Re: Oil drain for twins

Got it, thanks for the help guys. I'll figure out all the hose and fittings I need for the feed/drains,order that, then start working on the new manual brake setup.

Brian
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