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With the engine torn down it was time to tackle the mountain of RTV that was on everything in sight. A combination of the three below with various types of scrapers and brushes was somewhat successful, with enough patients it would eventually take most of the RTV off a surface, and the remainder would come off with a pressure washer but it wasn’t giving the super clean finish I was after. The other issue was the casting on the engine block and front cover are very rough from the factory and suffer badly with oxidation and no amount of chemicals and pressure washing at close quarters was going to leave them looking nice So after losing the will to live, and valuing my hands and lungs I decided to send the parts off to a local guy who does Vapour blasting. A friend had used him and he was highly recommended. As it turned out he was an absolute gent and a car nut, with a lovely 911 and BMW 2002 out the back of the workshop. I have to say his attention to detail was only what you could get from a proper car guy too, he was extremely careful to protect all the bearing journals and plug all the oil galleries. Nevertheless I fully de-greased, and power washing all the parts again for good measure to ensure these is no small particles anywhere before they even go for machining where they'll get cleaned a few times again. But I think the results speak for themselves, you can still see how rough the castings are, and nothing short of polishing them would remove that but they look better than factory fresh IMHO. While at it he also de-carbonised the cylinder bowls, and each of the valves. the heads themselves will get skimmed so mating surface will be cleaned up when machined.

It's the immobiliser. It's always done it.

Hi Folks I'm a long time lurker in the background and I've been building my racecar progressively over the last numbers of years but I thought it might be interesting to put my project thread on here. I've got some great info on this forum over the years so time to give a little back To start with this was how the car sat when I originally bought it in 2016.The car had been advertised for a while and I’d been keeping tabs on it in the hope it might still be around when I’d be in the market, as it happen the stars aligned and I found myself beating a path on a cold Feb morning to Momentum Motorsport outside Lisburn to collect it. The car has a bit of a back story (sure what car doesn’t), essentially it was a pre-production GT86 that was taken from Japan and JRM Engineering apparently set about creating a Clubman version for a prospective race series, as it was the very early days for the GT86 and the aftermarket wasn’t really there yet, JRM developed most of the parts with suppliers. As it transpired the car only ever completed one demonstration/shake-down day at the hands of Phil Glew and spent the following 4 years tucked away in a shed. It would later be sold to Momentum Motorsport as part payment for parts or the like, and next up it was yours truly. What initially got me interested in the car was the fact that JRM had built it, they are better know for GT1 and GT3 R35 GT-R, LMP1 and Group N rally cars, and their builds are generally in the realms of unaffordable but this was obviously at the other end of the spectrum. As you’d expect for a car with just 250km on the clock, it was immaculate and the quality of the build was exceptional. The interior has been fully stripped, wiring tied up, a custom weld in cage installed, plumbed with airjacks, fire extinguisher etc and the interior professionally resprayed. Underneath the car was spotless, the only thing that wasn’t really to my liking was the bodykit, the rear bumper in particular not being to my taste, but it’s a racecar so you can gloss over these things.The engine was completely stock back then aside from a HKS panel filter, HKS intake pipe and rear section exhaust. Given the cars are known to underperform and rarely ever dyno at the 197bhp as advertised it’s safe to say the car was going to be the slowest car I’d driven around my local track (mondello), but that was irrelevant to me as it was all about the chassis. JRM had fitted a set of KW coilovers, and while under there also fitted a set of AP 6-pots to the front, and 4 pots to the rear.

That does look good! You're a braver man than me 😂 Good luck with the rest of the build, looks great so far. Excited to see how it finishes

I mention it in the video actually I'm going to cut out the "V" light section and glass fibre it in to the V2 diffuser. Having owned a glass fibre bodied car in the past time not too bad at it and it shouldnt be too tricky with some patience.

Seems like a good time to bump this thread in the current climate, with the restrictions going out seems like a good idea to do Covid 19 polishing! Seems like a good way to view the rafters in the garage 🤔👍

Awesome build. I used up my daily allowance of likes otherwise I would have given more! Look forward to seeing further updates.

More recently progress have been slow and unfortunately the 86 has started to fight back... First up was the install of the new straight cut gearbox, I must have spent 8 hrs under the car trying to align it. The pilot bearing alignment is a real pain on these cars and as it turned out my improvised alignment tool which has worked previously didn’t like the combination of a slightly worn clutch plate. So I had to wait a week for the specific Subaru alignment tool to arrive, and luckily it did the job and within an hour the gearbox was fitted. (Lesson learned on just buying the right tool for the job!) Next was a fight with the exhaust manifold, after taking it off the car it lay on the floor for about 2 months. However when I went to install it onto the new engine it just wouldn’t fit, nor would it fit the old engine, so clearly it had deformed while sitting off the car, presumably from heat cycling and residual stress. I tried spreading the flange plates with a bottle jack but it just won’t hold a shape and keeps springing back regardless of how much pressure I put it under. So unfortunately I’ve had to purchase a new manifold which I’m waiting on. While at it I’ve decided to take the plunge and change out the only remaining piece of OEM exhaust which was the front pipe with contains a secondary CAT, so I’m going replace it with a new twin resonated HKS front pipe. The final punch was the coolant system, and I have to take responsibility for this one, about 3 yrs ago I noticed the car was low on coolant while on track. At the time I kindly got some coolant off a Friend to keep me going. I gambled that it would probably be OK, but I wasn’t aware just how unique the coolant was in the GT86 and that it would react so badly with the topup. Unfortunately while taking apart the existing coolant system I’ve noticed that it is full of red silt and it’s pretty well much stuck to every surface. By comparison the donor cars coolant system was squeaky clean after 20k miles As the car sits now I’ve installed the donor cars radiator and piping, and reinstalled the supercharger However having thought on it some more I was not happy that the heater matrix will still be a source of silt and I can’t flush it out sufficiently so I’m going to bypass it. As this will put a little more pressure on the coolant system I’ve decided to upgrade the radiator to a high capacity Mishimoto Radiator and add their upgraded shroud with larger fans, to be fair the OEM radiator is very thin....so the front end will be coming off again once they arrive, assuming COVID doesn't get them first!!!!! Thanks again to Part-Box for the latest round of purchases too [mention=2716]Lucas@PartBox[/mention]

Eventually I got around to lifting the original engine out of the car and sitting beside the new short block Unfortunately the progress after this was not a swift as I hoped. I ran into quite a bit of difficulty trying to get the valve clearances correct. Toyota love me, this is the First round of shims I bought off them!! Essentially I built up the engine with the first set of shims installed, all clearances were within spec, and I got as far as setting the timing. At this point I rotated the engine by hand and rechecked the clearances only to find they were out of spec, some by a significant margin. I came to the conclusion that the valves with the new springs installed had seated properly when they were rotated through a full rotation of the cams. So hence back to Toyota for round 2 and another lot of shims! A further 10 shims later, at 13 Euro each and suffice to say the heads had worked out quiet expensive. It took a few weeks to get beyond the valve issue, and it was a real pain to have the engine assembled only to have to take it apart again, but at least now I can claim I’ve built the engine twice!! I also got another attack of the “While your in there” and bought theses DW 900cc Injectors (Thanks to [mention=2716]Lucas@PartBox[/mention] and a DW 65c (265 lph) pump which should keep the injector duty cycle sensible and ensure the fuel pressure doesn’t drop off at the top end. As the engine is 12:1 comp ratio and will be running unrestricted it may take a little enriching to keep knock in check.

While at it I also disassembled the oil pressure relief valve to inspect it and make sure there was no debris from the porting that had been done on the oil galleries in the front cover. As I couldn't really progress any further with the engine build until the new shims arrived I turned my attention back to the car and its current engine and gearbox. Safe to say I’m covered from gearboxes anyway. Although I’m really hoping the PAR straight cut gear set in the second gearbox in the photo below will mean I don’t need the backups any time soon!! Next up was to take the HKS supercharger off the existing engine, as I didn’t want to drain down the cooler, filter etc as the HKS oil is just stupid money and I’m not near needing an oil change, I opted to take the entire front off the car and managed to remove almost all the setup intact without breaking any lines. To be fair removing the engine and installing the new one is much easier with the front off anyway. While at it I removed the restrictor plate that the supercharger is currently running with, and you can see from the grime how much larger the intake will now be! With all that removed the existing engine was ready to be lifted out. I also needed to swap over a few bits and pieces that were modified to fit the supercharger originally so I planned to do that while all engines are out on stands.

The Short block eventually has landed back from the machine shop with the shiny new rods and pistons installed.First up was to build up the heads which have been skimmed and lightly ported, The valve seats were also cleaned and valve shoulders re-cut so I was concerned that valve clearance may not be correct even though any changes were accounted for by adjusting the valve stem length.Unfortunately with the heads reassembled and clearances checked multiple times, there were quite a few out of tolerance.I want to have all the valves clearances not just in spec but sitting at exactly the same clearance, so I’m currently waiting on Toyota to get the exact shim sizes into stock. It held me me up a little on building up the heads but I wanted them perfect.There is also a know issue with valve seat compression where the valve clearance on some newer low mileage cars actually go out of spec (tighten) and cause major issues and perhaps that was the case with this engine.Another issue I came across was that one of the oil control valves in the heads was actually damaged, they are essentially a small strainer that restricts oil flow into the heads. I’m not sure how it happened perhaps during my cleaning, but regardless I’ve replaced all four of them in the two heads.While waiting for the shims to complete the heads, I cracked on with the other end of the engine, fitting the lower cradle and new larger diameter pickup tube. Aside for that I spent an awful lot of time cleaning and degreasing parts and wire brushing bolts to clean the threads for reinstall! You really don’t see much progress for a full Saturdays works.As the heads are made up of three parts I was able to go ahead and torque up the mains with the ARP studs and nuts, and new thicker Cosworth head gaskets.The ARPs are torqued up to 95Ft.lbs each and it feels a little sketchy as it’s so much force but they all got there in the end.

The last few weekends have been spent wiring up and figuring out the best locations for all the various bits and pieces needed for the accusump, AIM MXP dash and the Motec ECUI’m was not a fan of the Binder connections that came standard on the AIM looms, their an absolute pain to wire/solder so I converted any connections I’m using to Deutsch DTM, and likewise any wiring running to the engine bay has DTMs on that side of the bulkhead so that everything can be easily disconnected.I’ve also made sure that the accusump wiring allows easy removal of the relays and fuses within the engine bay and I picked up a 12” extension for the schrader valve so that it can be routed to a spot that will make topping up the air side of accumsump a doddle in the engine bay.The way I’ve wired it only requires one relay to be pulled and a small bridge installed to default the full setup back to the basic pressure switch setup. If the need arises it will be a 2 min job trackside.Next up was finding a home for the Motec M150. Unfortunately because the roll cage footing sits where the standard ECU would normal be mounted in the passenger foot-well it was not possible to fit the Motec there, in fact the OEM ecu has always just been hanging freely off the loom so not ideal regardless.I decided the glove box was probably a good location for the M150 and it would keep everything nicely out of the way.In order to route the Motec loom so that it could pick up the standard ECU header I had to cut the side out of the glovebox and also make a bracket to mount the M150 on.After some fettling and a little bit of paint on the bracket it was sitting nicely in the glovebox. I also pinned out an extra CAN output from the ECU to run to the MXP dash, and while at that I created a new lead to extend the Lambda to CAN module so that it can be mounted in the engine bay where I’ll be putting a new Bosch wideband Lambda Sensor in the exhaust header.

To be honest I’m not 100% sure on it, I believe it’s part of the DAMD black edition aero kit that was originally installed by JRM, it’s a one piece fibreglass part that covers the entire boot lid.

Also went with a new set of OEM main case bolts, they seem to be commonly used in a lot of builds so will be more than up to the job For the head bolts I’ve gone with ARP hardware. The OEM are a bolt type whereas the ARP are a stud and nut design, but again pretty much every builder seems to use them I had also been looking for some up-rated GSC viton valve stem seals and I finally found some with a supplier. But I was really struggling to get the new bearings. I wanted to go with KING racing p-max bearings and their newest polymer coating (p-kote) for both the mains and rods as it will give a little margin of safety in low oil supply situations, but a lot of suppliers were struggling to get me a set so the build ground to a halt for a little while.

The other piece of the puzzle is the front cover, the oil pump assembly sits in the front cover and all the oil feeds to both heads, and the main block are routed through it. Its a bit of an unusual set up as the supply lines are simply covered with machined covers and held in place with machine screws, there is no sealant on the covers so they just pop off, its almost hilarious that they covered the engine in RTV yet don't seal these covers which hold back all the oil pressure, and any leaks will drop oil pressure to the engine itself!With the covers off you can see the oil pump and feed linesPlan was to port the lines that lead to the main gallery only, the heads in the FA20 don't suffer from a lack of oil flow and the main gallery is not a priority feed either so the LHS head actually gets fed before it.So it might be all well and good enlarging the galleries but it won't be much good if the pump cant keep up! So I planned a few other modifications tooFirst up a new, high capacity oil pump. The OEM pump has a strange profile, and its also sintered metal and has been known to fail in some engines, so the replacement is a billet piece with the same profile as used in the FA20DIT as found in the Subaru WRXSo the pump should look after the increased oil supply but only if it can get the oil from the sump in the first place, so to help that I'll be changing the pick up to a larger type with a straight line from the sump. The OEM one is a smaller diameter and has a restrictive bend in it too, a few people has noticed cavitation marks on the pump housings during builds so hopefully this will address this too.The other benefit is the upgraded pickup has a larger mesh too so hopefully its not as likely to clog from strands for RTV!!!

So with that lot apart it was time to examine the oil galleries and come up with a plan to address the FA20's shortcommingsFirst up is the crank, the crank has 5 main journals, but only 3 of them provide oil to the 4 big end journals, and here in is one of the issues, almost 100% of bearing failures in the FA20 are rod 2 or 3, and if you look at the crank you can see why.The first main journal on the right feeds Conrod 1, and the last main journal feeds Conrod 4, so that leaves main journal #3 feeding two conrods yet it isn't sized to supply twice the oil volume, so whenever oil flow/pressure drops in the engine these two rods get starved and eventually you end up with at least one of them spinning a bearing.The main galley runs just below the journals where the red arrow is show and the plan is to drill it out to 12mm from the front of the block as far as No.3In order to get the full benefit though, the galleries the whole way from the pump supply in the front cover really need to be enlarged too.So the front of the block needs to be ported where the oil enters from the front cover. The oil path to the main gallery below the journals is a bit convoluted as its not a straight shot from the front cover, it comes in the top hole, travels down and then into the block, the hole that actually sits at the front of the main gallery in the picture below is capped with a timing chain tensioner but at least it will allow access to run a 12mm bit down the main gallery.

So with the heads out of the way it was time to split the block, even the head gaskets get some RTV for good measure, there was a surprising build up of carbon in the cylinders too for a low mileage motor!With the gasket removed I did however noticed a lot of sludge built up in the coolant passages which is a little concerning, I've heard of others coming across this aswell, apparently some form of coolant contamination from the factory sealants or something, but it had me contemplating a switch to running it on a waterless coolant.Next up was splitting of the block, and as expected they decided to glue the bloody think together aswell! To be fair prying most of the sub-assemblies apart was relatively easy with the right tools and a bit of care, but splitting the block was a bit of a pain, you can see the seams of RTV running down where the block halves meet.A few taps of a rubber mallet was never going to do the trick so I broke out a mini bottle jack and gently pried the halves apart at the bell housing end, while being careful not to damage the block, eventually the two were apart

The RTV party continued at every turn....I've heard of places billing huge hours just to clean an FA20 down for reassembly, I can understand why!The heads have a couple of caps etc but they also are made up of two assemblies, the cams sit in a cradle assembly that sits above the heads themselves, again plenty of RTV for good measureWith the cradle and cams removed I could finally get access to the head studs to take off the heads.At this point the sensible thing to do would have been leave the heads alone, just stick with the original plan to drop in some relatively cheap rods, a good set of bearings, keep the OEM pistons and call it a day.....so obviously I didn't do that... so out came the valves, and springs

A good mechanic is always worth travelling the longer distance for