this is a writup i did for celicasupra.com with various info ive read all over the place and pics if found or been sent by various individuals. just figured you guys would like to see it. btw, my mkii is front sump so a couple lil things wont apply directly to you mkiii guys. here it is.
ok, first off, i havent done all these mods myself as of yet. this is just to show people what i WILL be doing on this current buildup to make this engine as bullit proof as possible. alot of these things are cheap, some arnt, but all in all i think they will make the oiling system the last thing anyone will have to worry about again. now, with that said, this is my opinion at this point how to solve it and not a fact as i havent finished yet. though im getting asked questions about it and since i have prolly done more research on this then most anyone else, i figured id do this writeup to answer some questions and shed some light.
step1: the first thing you need to do obviously is rebuild the engine and make sure its assembled properly with the proper tollerances etc... while doing this there is a very cheap set of items to replace most people never think of that are very important to replace. and that is the SPRINGS in the OIL SQUIRTERS!!! nobody ever thinks to replace these, yet obviously they are old and worn out and opening at lower oil pressures then origonally designed. i myself plan to test them and possibly replace with stiffer then factory replacement springs. this is a must imho. do it. they arnt that much from the dealer. heres a pic of the oil squirter.
and heres the page of the tsrm that shows the location of the bolt that needs replaced for the oil squirters. the bolts part number is part #15703-66010
also. get a REAL oil pressure gauge to replace the factory one. the factory one is iffy at best. doesnt really let you know whats goin on. and its easiest to install the sender for an aftermarket gauge while the engine is out and being rebuilt.
step 2: the oil pump itself. most of us use the 5m oil pump which is fine, but what you might not be aware of is that wether you are using the 5m or 7m pump, there is a clearance from the gears, to the lower case. there is a minimum and maximum tolerance. what you need to do is measure that, and then have the cover machined at the machine shop to put this as close to the minimum clearance as posible (the cover is held on by several 10mm bolts). this will increase the volume output of your oil pump significantly if it is worn alot.
also, the pressure releif spring wears as well. this regulates the max pressure of the oil. this is a linear spring, so it does open before max presure is realized. if someone tells you it stays closed till max press they are full of crap. it is not a solinoid acting as an on/off switch, it is a simple spring, it starts being compressed the moment any pressure is applied and is fully open by the max oil pressure. what i recomend is to shim this with ~12mm thick of washers to tighten it up. it will increase your max pressure by ~15psi or so, but will increase the lower rpm pressure much more dramaticly, as itll have to push harder to start opening. now if your worried about it dont do it, but i highly recomend it, and have done it myself.
step 3: here is what you currently have to feed the oil from the pump to the block.
it has a banjo fitting on the end coming out of the oil pump which is horrible for flow, and it also is a crush bent tube, which hinders flow at every bend.
this is what i recomend. it is a 8an line running from the oil pump to the block using 8an adaptors. you need a 3/8npt male to 8an/jic male for the fitting feeding oil into the block from the pump and a 18mm 1.5 thread to 8an for he fitting coming out of the oil pump itself.
heres for a 7m in a mkiii with midsump.
and heres a 7m in a mkii with a 5m pump and front sump.
(wouldnt let me put more then 20 pics in one post. )
notice the line isnt touching anything and cant. wont touch the pan either, so itll hold up fine. hose is good to 300deg and 1000psi as per the company that al the parts come from. they verified it wont hurt the hose at all to be submersed in oil.
if your interested in buying the fittings and the line already made up as a bolt in kit pm me!
step 4:here is the stock 7mgte oil filter adaptor next to the 5m motor mount.
notice the interference issue, which is easy to rectify and will help the oiling system. the stock 7mgte oil cooler design is a very poor engineered one. it is a pressure controled spring that regulates oil flow to the oil cooler and then back to the pan once a certain pressure is reached. this spring also wears and would need changed, but since even a new spring still alows oil pressure to be wasted and fed back to the pan, it should at the minimum be replaced with a spin on adaptor for a oil filter relocation kit. heres a pic. it is on the block with 8an fitings attached. 8an ss braided line will be perfect to run for the external filter adaptor.
now thats an efective fix, but for the more hardcore like me, here is what i plan to do.
those are 8an fittings. one is threaded into the center of the oil filter location, that is the return to the block and feeds the main oil galley. the lower one has had the lower cover plate removed, and then tapped for the fitting. this is the feed from the oil pump. now heres an important note. this fitting has the full diameter feed from the inlet to the block from the pump. above this it tapers down to a smaller diameter to feed the oil filter normally. this passage will need to be plugged. the guy i got the pic from welded an extension to a tap and tapped the passage where it tapers down and used a threaded pipe plug. i may do this but may also just weld the port shut on the outer part of the block. i havent decided just yet but either way, this is the outlet and inlet setup i will use for the oil system and it will alow for the best oil flow. i will take and post pics when i do this.
step 5: since you should be throwing out the stock oil cooler setup, with the use of an external oil cooler setup, you should get a good quality oil cooler and an oil thermostat. here is a pic of an oil thermostat.
the purpose of this is to regulate the oil temperature, but also, even when oil is being sent to the oil cooler, it is still being put to the engine so no oil pressure is wasted back to the oil pan. this should be plumbed in after the oil filter, so the oil should flow from the block, to the oil filter, then from the oil filter to the oil thermostat, then to the block. and then the 2 ports on the thermostat designed or the oil cooler should go to and from the oil cooler of coarse. heres a pic of a place you may want to mount the oil filter.
also just to note, some oil coolers have built in thermostats, such as the rx7 oil cooler i plan to use so this cuts down on the amount of parts i need to buy and the lines i need to run. if you use a oil cooler with a built in thermostat then you dont need the external oil thermostat.
now, at this point you will have a very soild oil system, but, it can still be better. and heres how.
step 6: get yourself an accuspump and plump it in after the oil filter and cooler. this has 2 benifits, first, you can use it as a preluber to lube the engine before starting to ensure the maximum life of your engine bearings, and second, it can be set to realease oil into the system anytime the oil pressure drops suddenly below a preset point. this can save you incase of some strange emergency or accident.
and yet another important thing to make the system even better.
step 7: upgrade the oil pan for one with a larger sump to hold more oil and that has baffles. i myself will be fabbing a new oil pan, and will take lots of pics and do a writeup when i do it and may offer to do it for others. this is common practice on domestics, and for good reason, the more oil your system contains, the less likely you are to run low. heres some pics of the group a magnesium pan toyota built for the group a mkiii race cars as an example. toyota themselves knew it was needed for high power racing conditions.
anyhow, thats what i got for now, if i skipped something or remember something i forgot to mention ill edit it later. and will post other/better pics when i find them. enjoy.