Thread: HOW TO: "Indentify" a 10:1 vs 9:5 SR20 motor by Oil Drain Tube?

I recently put a high comp motor into a local pulsar.

Upon receiving the engine - its had the short oil tube.


But it also had the cast gay iron manifold.

But i also know its a high comp engine as it was built in late 2003 from what we can tell.

I hear ya.

From what I have seen though all of the engines with the Nissan Header always came 10 to 1.

Well once you know for sure the motor is 10 to 1 or 9.5 to 1 we will be 100 % sure.

My point on the longer tube is that the longer tube is based on the header and the clearance of the heatsheild for the header, than having anything to do with compression.

I am sure the 11.5 to 1 Autech motor comes with the cast manifold also which has the short tube.

Actually something just clicked in my head to explain the oil tube theory - and throw it right out the window.


Late RR DE motors came with the cam cover, which is the same cam cover as VE motors. These dont have the oil seperator box, which normally feeds straight down to the short oil tube.

So, IMO(which could be totally wrong), the Oil drain tube, is totally dependant on the year or production of the engine, which is basis for the type of cam cover the engine has.


I also come to this conclusion in the proof that my autech motor, had the stainless tubular headers, but also runs the short oil tube arm!

Dont mix up RR-VE motors and the older 10 to 1 Highport and lowport motor. They have nothing to do with eachother

My UK motor came with UK accessories from a parts manufacturer "Lucas". You can read it right off the water pump and distributor housing. Plus the igniter chip was grey (ratehr than black) and the bracket was different. It had a production date of 10/91 iirc.

Also the hole in the intake manifold for the idle air bypass that goes to the intake tube is larger diameter.

Mine also had the sodium filled exhaust valves (no oil squirters). I have read that they have slightly larger cams compared to other highports and the head was cleaned up a bit compared to other highports. These remain totally unsubstantiated but it would be nice to confirm/deny them.

when i got the motor it didnt have the tubular header, and when the dude i got it from it didnt have the tubular either, so who knows

What are we calling tubular manifold? The one the MR guy pictured in his first post? If so...

I picked up a 92 se-r with a silver valve cover, tubular manifold, and single bend oil tube. 10.5:1 or 9.0:1? Who knows, but it had the stock intake manifold.

I also justed ordered a high port sr20 that was advertised as a JDM from ebay. This sr20 I just picked up from ebay has a silver valve cover, tubular manifold w/ heat shield, and I forgot how many bends. It fits well.

* i dont remember how many bends my new high port has.

^^^^
Somewhere around the bottom right corner you see the oil tube popping around the tubular, right around the heat shield. Proving Miko's theory.

^What company did you order that motor from? It don't look to bad.

Thats a 92-93 SR20 JDM motor high port, clearly seen by the valve cover paint and the external coil setup.

I have 3 of the newer JDM highport motors with the B14 style Distributor, that are much cleaner than that one and because of the years should have less miles. The motors I got are 95-98.