The Oldsmobile Connection

speedy266 · Joined: 25 Jun 2003 Posts: 347 Location: Ontario, Canada

i need some tips to get the most out of my engine, my car doesnt pull hard enough :( i need more. I have the series I 3.8L i was wondering wats the best spark plugs for performance, i have the ac delco ones right now after the rebuild, gapped at .060 the manual says .080 but i heard that that was wrong, wats the best gap for these engines. any tips would really help right now, there isnt much aftermarket parts for this engine:(

86Delta · Joined: 06 Nov 2003 Posts: 281 Location: NJ, USA

i would go by what the emmissions sticker says under the hood. it tells you the plug gap on that. .080 is too much, i'm pretty sure it is .060. your engine is not a series 1. series 1 refers to a 3800. your engine, like mine is just a plain sequential fuel injection 3.8. depending on what ignition system you have, either a single coil with 6 terminals on it, or 3 seperate coils with 2 terminals each you can upgrade the coils. Accel makes a high performance coil to replace the single unit and MSD makes the individual 2 tower coils. you can get a cut to fit MSD wire set for it too. but as far as anything like a cam, headers, larger throttle body or even a cat back exhaust, i think you are SOL. just a muffler and a K&N air filter has little or no performance gains, thats what i experienced anyway.

speedy266 · Joined: 25 Jun 2003 Posts: 347 Location: Ontario, Canada

u have the 86 3.8 right, mines 85 i saw pics of the 86, and they look alot different, also i think mine is MPFI thats wat it says in the service manual anyways. im not sure how to post pics on here if u give me ur email i can send a pic of wat my engine looks like, theres a pipe that goes from the valve cover to the air intake tube, wats that for??

86Delta · Joined: 06 Nov 2003 Posts: 281 Location: NJ, USA

that pipe from the valve cover to the intake tube is a breather.

my engine looks different than yours? are you sure you have a 3.8? they had 3.0's in 85-86 too, they looked a little different, they had a distributor instead of coil packs. as far as i know the 3.8 in my car was the only one for that time period. there are 2 different VIN numbers but they still look the same.

speedy266 · Joined: 25 Jun 2003 Posts: 347 Location: Ontario, Canada

i have the 3.8L for sure, and yes its different from yours, the looks of everything, when my timing chain broke, i got a used engine, and the service place took 2 weeks just to find my engine because its so rare the one i have was only in the 85's i believe. I dont have pics of my engine but i found someone who has the exact same one as i do

http://www.sounddomain.com/memberpage/252213/2

theres the link

the breather, i thought it was that, ive seen some cars where the breather is just a small filter that sticks off the valve cover, thats the point of making it go to the intake tube??, wat is the function of the breather anyways, i was thinking of sealing the hole on the intake tube, and taking it off and just putting a small smaller on the side of the valve cover...

OldsGuy · Joined: 16 Feb 2004 Posts: 269 Location: Lees Summit MO

Speedy, that breather tube is part of the positive crankcase ventilation system (PCV). There are usually breather holes on each valve cover, one is usually connected to an engnine vacuum source on the upper intake manifold or someplace else, I know of carburetted V8s it may be at the carburetor baseplate, anyway, the other one goes to the air filter box, usually outside of the big air filter. This breather tube vents gases from the inside of the engine, from the block, through the head and up to the air box, these gases are introduced to the intake to be mixed with the incoming air fuel mixture and re-burned in the combustion chambers. The other side, connected to engine vacumm, usally has a PCV valve on the valve cover and provides some "suction" to cause a positive flow of gases from one side of the engine to the other. In the case of straight fours and sixes, I have no idea how they do it.

I wouldn't change that on your car since it has a computer that controls the combustion process and has many sensors throughout, removing that may affect the car's performance adversely. By all means, don't seal it up! On older V8s people sometime replaced both of them with vented chrome breathers that look like a little inverted cup. Anyway, good luck.

86Delta · Joined: 06 Nov 2003 Posts: 281 Location: NJ, USA

also if you seal it up the engine will build too much pressure in the crank case and cause oil leaks. yeah, that is different, never seen a 3.8 like that before. that sucks that it has V belts, 86 was the first year for the serpentine belt with an automatic tensioner.

speedy266 · Joined: 25 Jun 2003 Posts: 347 Location: Ontario, Canada

i actually like the V belts i can take off the power steering and ac compressor belts, and leave the alternator one on, hehe gain some power hehe, also its safer i find. I got one from the crank to the ac compressor, one from the crank across the water pump to the power steering, and one from the crank across the water pump and to the alternator. one time the alternator one broke, but i was able to to keep going cause the water pump was being spun by the other belt. has anyone every broke a serpentine belt before?

86Delta · Joined: 06 Nov 2003 Posts: 281 Location: NJ, USA

well i carry a non AC belt with me and an 18mm wrench for the tensioner. i just kept carrying it around even efter i did my compressor, it used to sound like it had rocks in it so i thought it might sieze/explode.

even though if a vbelt breaks it only takes out that one accessory, i wouldn't ever trade a serpentine with an automatic tensioner, just set it and forget it. the way i see it, not everything can be fixed on the side of the road, so it doesn't really matter to me. the automatic tensioner is definetly on my list of greatest automotive innovations.