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In 1995, all sr motors came with a new design timing chain tensioner. It is pictured on the left. It extends in about a 1/3" further to take more tension out of the chain. This helps keep things quiet as the chain stretches over the years.

why does the GTi-R have 8.3:1 compression and all other sr20det motors have 8.5:1? In the picture above, the head on the left is a bluebird or a s13 sr20det. same as a sr20de from a b13. On the right is a RN14 GTi-R head. You can see that the head from the GTi-R has a perfect circle dish around the 4 valves. The other head doesn't. that is what makes the GTi-R have lower compression. The pistons on all the highport and GTi-R sr20det motors are the same, with a 54C stamped on the top, which makes you think every det motor has GTi-R pistons! But no, they are all the same.
Oil in my turbo and intercooler piping?
So you take off your intercooler piping and notice there is a little puddle of oil. What caused this? It must be bad turbo seals right? Most likely not. On a sr20, your problem is more likely to be cause by blow-by. Blow by happens on all engines. The question is to what degree. On a turbo motor, you will get more as the cylinder pressures are much greater. That pressure sneaks past the gap in the compression rings on the pistons and pressurizes the crankcase. There are two vents to get rid of this pressure in the crankcase on the sr20. The pcv fitting on the valvecover is one, but this is a one way valve and is only working when you are not under boost. The second is the "T" on the valvecover. One side of the tee runs to the black box (oil separator) and down to the block. The other side goes to your intake just before the turbo (see arrows). Oil is pushed up from the block, thru the oil separator and to this "T". And as mentioned before the other side is going to the intake! so the turbo is sucking in the clean air thru the air filter, and then also all of the blow gasses that will include to a degree, some oil. How much oil will depend on how worn the piston rings are, and if there is a crack in one piston, you will get much more.
So don't assume its a bad turbo.
Don't assume your motor is shot.
And don't remove the oil separator or change its hose routing unless you have to, and using a catch can is a must in this case.
Does your SR20 have a "TAP-A-TAP-A-TAP-A-TAP" noise? The most likely suspect is air in the lifters. If you look at my finger location in the picture, I'm pushing down on the back of the rocker arm on the section that rides above the lifter. While pressing, if you feel any movement, you have air in that specific lifter. SR20 lifters are hydraulic but can not bleed themselves like most hydraulic lifters. To bleed your lifters you must remove your valve cover, the cams, and rocker arms. Pull the lifter out of its sleeve making note not to tilt it sideways, submerse it in oil, and insert a thin piece of rigid metal inside the hole on top of the lifter. Keep in mind, entire lifter must be completely submersed in oil. You will feel a groove with your metal probe, if you press down it will compress the internal mechanism. Do this repeatedly, many times, or until it doesn't depress anymore. Carefully insert it back into the sleeve without tipping it so that air does not enter it. Reinstall the rocker arms, cams, and valve cover and listen to see if the noise persists.
"Does my FWD SR tranny have a factory LSD?" It does if it looks exactly like this. If the housing looks different where the driver's side axle goes in (does not stick out as much) then no, your tranny does not. If it looks like the one below, then it is NOT a LSD equipped tranny, but for $219, you can buy the LSD from us.
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