Need advice tapping oil pan for turbo drain

[RedZMonte]

as long as its above the oil level it can go into the pan a little, shouldnt be a problem. I had a "OIL RETURN FLANGE" welded to my pan so i won't leak then just clamped the hose to it. its hard to get in there and tap it for a thread.. mine looks kinda like this.. More of just a nipple (trimmed most if the actual flange off and welded the nipple and a little bit of the flange (just enought to cover the hole) to the pan, again all done with pan on the car.

[Schmieder]

as long as its above the oil level it can go into the pan a little, shouldnt be a problem. I had a "OIL RETURN FLANGE" welded to my pan so i won't leak then just clamped the hose to it. its hard to get in there and tap it for a thread.. mine looks kinda like this.. More of just a nipple (trimmed most if the actual flange off and welded the nipple and a little bit of the flange (just enought to cover the hole) to the pan, again all done with pan on the car.

I know its a tight spot to work in but the radiator and a/c rad will be removed along with the starter and other things to ease the access. I'm going to try to place the turbo w/o having to remove anything like a/c lines. The only thing I am sure that has to go is the battery, right to the trunk with it. And having a sunroof, the battery is getting a full casing. The sunroof has been known to leak a little into the trunk. I had to drill a hole at the bottom of the spare wheel well to prevent build up during heavy rains. Other wise the trunk would stink like ass.

I hate trying to work around something when it could be removed to make the job easier. I'm all for short-cuts but if there is any chance of messing up, I'll take the long road and do it right.

I'm still wondering where to exactly tap the oil pan. Near the starter would be nice but I may require a 90* AN fitting to pull that off.

Where did you tap your oil pan, if you don't mind me asking?

As for not leaking, I'm confident a nice and tight 1/2 thread tap with thread seal and a rubber o-ring designed to withstand oils and fuel would be good enough. I have a 1/2" male to 5/8" barbed fitting. It will be a nice and snug fit to the -10AN return line.

Question: How many degrees off angle can I have the turbo return? As in ideal placement on the turbo itself would place the oil return flange facing straight down. I wonder if a 20* offset would be ok?

[RedZMonte]

mine is just to the right (if facing the front of the engine under the car) of the passanger side lower motor mount and to the left of the starter (so basicly just between the 2). basicly anywhere in that basic area is fine (easy to access and not obstructed). just make sure you don't put it anywhere where the starter or mount will block it.. The angle should be fine, i just clocked min so that the drain would plug in and run down to the fitting, as long as its not horizontal it will flow out
You can see my drain is angled just enough to flow freely (the blue hose off the turbo)

[pocket-rocket]

Having someone with a spare engine apart would work wonders where to put a tapped one too, if it sticks inside the pan any. That way it doesn't get whacked shut by a rod or counter weight.

[Schmieder]

Having someone with a spare engine apart would work wonders where to put a tapped one too, if it sticks inside the pan any. That way it doesn't get whacked shut by a rod or counter weight.

That has been a concern on my mind. What I plan to do is measure the oil pan thickness in relation to the adapter being threaded in. Once I know exactly how much protrudes into the oil bay, I will insert a feeler at the same length and hand crank the engine. If I see the feeler move, I will have to flush the adapter. If not, I'll advance the feeler a little bit to see how much clearance I have while hand cranking the engine.

If I have any interference, I'll just have to get my carbide and grind the adapter down or use rubber washers/o-rings to make up the length difference.

Any one know the general thickness of the oil pan?

And how strong is the Aluminum Oil Pan? Basically looking for a torque figure when tightening the oil return adapter to the pan. It would suck to strip the threads.

mine is just to the right (if facing the front of the engine under the car) of the passanger side lower motor mount and to the left of the starter (so basicly just between the 2). basicly anywhere in that basic area is fine (easy to access and not obstructed). just make sure you don't put it anywhere where the starter or mount will block it.. The angle should be fine, i just clocked min so that the drain would plug in and run down to the fitting, as long as its not horizontal it will flow out
You can see my drain is angled just enough to flow freely (the blue hose off the turbo)

Turbo location is pretty straight forward. I had that spot picked out since hatching this idea. The oil return line was my concern in question but you generally answered my question. I'm just being extra cautious and inquisitive regarding turbo oil drain functionality.

Would I benefit getting a head gasket thicker to slightly reduce CR? I am, obviously 9.5:1, and the heads/pistons are very clean, no carbon creep compression increases to the stock CR.

I can easily calculate the CR when changing the head gasket thickness, on-line calculators are good there. Is there a standard rule of thumb regarding CR vrs PSI? I'm ultimately planning for 8 psi, no more. Figured stock internals are good enough to hold up to 8 psi with a good tune, intercooler and no KR or detonation (definitely will be tuned out) with a good AFR to keep the pistons cool.

Is there any merit/benefit utilizing a water/methanol injection system running 8 psi on stock internals? Figured if set up for boost, it could only help keep intake charge temps down and further safe guard against detonation.

In fact, will I be able to increase timing under boost further if using an H2O/METH Kit? Since temps will be much lower. Still using the stock PCM knock sensor function for safety purposes in case the h20/meth system runs dry or dies.

Man, I must be one hell of a refresher. I think I am getting close to asking every possible question regarding turbo install. Keeping you all on your toes, lol.

[pocket-rocket]

Questions now is much better than just slapping it together and screwing up your engine, car, and possibly killing yourself

[Schmieder]

Like my throttle body porting?

- All sharp edges were smoothed very nicely, the sealing area was left alone where the plate rests at idle.

- The throttle plate was tear dropped. The front edge is a perfect semi sphere edge and the trailing edge is knifed sharp.

- The top steel bar that secures the plate was removed flush to the bore. It was ground flush with the throttle at WOT to ensure a smooth flow at WOT instead of having a smooth area at idle

- The bottom steel bar was also tear dropped and the center was reduced.

- The bell curves towards the front of the throttle body intake has a special texture. At very specific places, I ground golf ball divots. It is known as the most perfect texture to reduce trailing drag. The texture is only present in convex areas and not the concave areas. This will help the air flow sticking closer to the throttle bore at the narrowest point.

- The screws were ground perfectly flush on the bottom.

- The throttle plate where the screws hold has a recessed angled pitch to allow the screws to sink further into the plate reducing surface area.

- The screw tops were carved in a tear drop shape and slightly reduced in height. The side are carved in more then the front and back of the screw head.

- The entire bore surface has been polished to a slightly less then perfect mirror surface. I can still see good reflections in the surface though. However, I may cross-hatch the bore surface. Which ever has better flow characteristics with surface tension.

- The stop surface was stopping the plate at 95%~97% WOT. I gently ground that down to get a 99%~100% WOT. Tested with multimeter and did not exceed the specifications, otherwise it will throw a code.

- All internal areas thoroughly cleaned well

The entire process, if viewing in a 2d manner, opened flowing surface area from a 52mm to compare to a 57mm. Might sell it since I am going 65mm now.


I am considering using JB Weld to seal up the EGR passage into the Plenum. Hoping it reduces turbulence and contribute to a more even cylinder filling. Any advice about the EGR?

[Schmieder]

Questions now is much better than just slapping it together and screwing up your engine, car, and possibly killing yourself

You got that right.

And you all are contributing to another GM turbo to snub those ricers...lol

I don't like those little hondas, ect.

[pocket-rocket]

I am considering using JB Weld to seal up the EGR passage into the Plenum. Hoping it reduces turbulence and contribute to a more even cylinder filling. Any advice about the EGR?

Disable it when you tune the car? It sounds like you put a lot of thought into that TB. If you are getting a 65mm, I would toss that reworked one on ebay (or in the for sale section here) with all those key points to help it sell.

[Schmieder]

Disable it when you tune the car? It sounds like you put a lot of thought into that TB. If you are getting a 65mm, I would toss that reworked one on ebay (or in the for sale section here) with all those key points to help it sell.

Yeah, thinking about it. But it is only a 52mm and for the price of a 56mm TB used, why purchase a chopped up used 52mm that performs just like a 56mm?

It is more of a garage statue point to show off to friends.

Not sure if I'm going to port the 65mm. As streetability might fade off and why bother since a turbo is pushing all the air I need and some.


Yeah, disable the EGR in tune AND fill the opening in the Plenum to help smooth air flow. The EGR entrance into the Plenum is a turbulant spot that could be rid of. It should help equalize air flow to all runners. At least equalize in relation to 1-3-5 and 2-4-6.