I have an 89 GTA 350.. and im putting a turbo on it.. i know where to tap the oil line feed but im wondering how i will route the return without pulling the motor to tap the oil pan or taking the oil pan off. Thanks

Sean

 

You can put grease on your drill bit and tap to catch the shavings. If you work slowly and carefully, it should work fine. I think this is how some supercharger (Paxton?)companies recommend fitting the drain.

 

Dont use a drill!!! it always drop some metal chips. Use a sharp pointed chisel to punch the pan. Make the punch about 1" from the top edge of the pan to bottom, be very carefull not hit any counterweight of the cranckshaft or rod. Make the punch so that a #10 AN bulhead connector fits. Cut one side of the bulkhead connector so that you leave only the thread where the nut goes and one 10 AN thread side. Remove the two engine bolts from the mounts and lift the engine as far as you can (check the distributor not to hit with the firewall) Remove all the pan bolts, separate the pan from the block and it should give you enoght space to put the bulkhead inside the pan. Put the bulkhead connector from inside/out of the pan, with the cutted side of the bulhead connector inside the pan and the thread for the nut and the #10 AN thread out of the pan. Put enought sealant and use a fixed wrench to hold the part of the bulkhead connector inside the pan and thighten the nut enought so that it wont come loose. The good thing about this method is that it dosent require to remove the pan out of the car for welding or drilling and it can be done in just a few hours. It wont leak or loosen, I use this method for oil return in all the cars that I turbocharge and none has ever leaked, is a very proffesional way to do it.

 

I would never trust anythin other than a welded on fitting, bulk head fittings may have the nut back off.

Also the whole punch a hole deal sounds like a lot of work. Just take off the pan an weld a fitting on it, it's not that much more work but will definetely not cause any problems later on.

The punch a hole and tap with a greased up tap sounds waaaay too bubba for my taste

 

If you are lucky you have an oil drain behind the fuel pump cover.

 

Yes, pulling the pan and welding a fitting in is the best way. This is the way I did it in my car. But he did specify that he doesn't want to pull the motor. I guess the greased tap idea was not a good one though. Just a thought I had, not the way I would recommend doing it. Wouldn't want to rig anything too much.

I think the FP boss would be ideal, too bad not all of them are open to the pan.

 

Remeber that he dosent want to take the pan off, and the nut is on the outside of the pan glued on by the same sealant, there's nothing that could fall inside the engine.

 

What do you mean, "not all of them are open to the pan?"

 

thanks alot guys ill get something in there to make it work

Sean

 

Worked fine for thousands of vortech and paxton customers.

-- Joe

 

There are many later model SBCs with no plate bolted over the FP boss, so there is no way you could put an oil drain there without drilling a hole (there is no cover plate there because there is no hole there is what I mean). I'm not sure this was the case with any 3rd gens, but look at some early to mid 90's GM trucks, and you will see what I mean. I guess GM did this to save machining costs.


I thought there was an SC company that recommended using a greased tap into the pan for the drain. Thanks Joe for backin me up on that! I thought next I was going crazy.

 

from Vortech's instructions:

3. OIL DRAIN LINE

A. Raise the front of the vehicle and
support with appropriate
jack stands.

B. To provide an oil drain for the
supercharger, it is necessary to
make a hole in the oil pan. It is best
to punch the hole rather than drill.
Remove paint around the hole area
so that it does not flake into the pan.

C. Make a mark on the oil pan on the
driver’s side ahead of the oil filter.
The mark should be 3" below the
third bolt from the rear of the pan.

D. Use a small center punch to perforate the pan and expand
the hole. Switch to a larger diameter punch and expand the
hole further to approximately 9/16" diameter. Most punches
are made from hexagon material and may be placed in a
socket with an extension to make this procedure easier.

E. Tap the hole with a 3/8" NPT tap approximately 1/4" deep.
Pack the flutes of the tap with heavy grease to catch and
hold the chips. Once the tap is removed, it must be cleaned
and repacked before tapping is resumed. Use a small
magnet to check for any stray chips after tapping procedure.

F. Thoroughly clean the threaded area with acetone or other
solvent. Apply a small amount of silicone sealer to the new
threads. Apply more sealer to the threads of the 3/8" NPT
90° fitting and secure it in the hole with the hose fitting
pointing forward and slightly upward. Make sure a seal is
formed all around the fitting at the pan.

G. Route the line forward along the top rail of the oil pan and
secure to pan bolts with the clamps provided. Temporarily
cover end of hose and secure out of the way.

H. Drain and replace engine oil and change filter.

NOTE: This method of rolling over the lip
of the hole and tapping it works well if
CAREFULLY done and should cause no
problems.

 

OK, but if there's a cover plate…

FWIW, my '92 K1500 has a blockoff plate, as does my '87 and '83 f-body

yes, but they expect you to open the hole with a punch. Using a punch rolls the edges of the metal back forming a shoulder that you can thread. If you drill the hole you don't have enough thickness for even one full thread.

 

Not trying to start an argument, but this proves my point. This is a truck we had in at work today, there is no openining in the FP boss to drain oil into. Notice that some of the holes are not even tapped. This was a 92 GMC K1500.

Like I said, I don't know if this pertains to any third gens, but there are many SBCs that dont have an opening at the FP boss.

 

All the vortec motors are like like. Besides, the turbo would have to be directly over it to drain properly.

-- Joe