25/07/2024
Thought i would do a writeup of the epic build that is Craigs Blue MR2 Turbo.
Came to me with a failed Gen2 build. everything was wrong. return line blocked, sump full of crap, crank caps finger tight, rod caps tight enough to break a 1/2" bar end... wrong sized main and rod bearings on a stock crank. (the mains were 0.50" over sized, but on a stock unmodified journal. )
on strip down it was found the crap in the sump was fillings, sand and rust. and it had gone everywhere.....
this started the progression into what it is today.
Set of CP 86.5mm pistons turned up. not brand new, but well within usable state.
the block, pistons and rings were sent off to AMS in Burgess Hill for machining. stunning job, each piston was matched to the bore, the rings were then gapped for boost and ground at an angle.
the deck was machined true.
it then went off for pressure cleaning to ensure there was no crap in it. all the gallery plugs were removed, and cleaned.
this was a Gen2 block.
we decided to go for a Gen3 setup. so a brand new OE oil pump was fitted, which mated to the gen3 aluminium pan, windage plate, pickup and metal sump. (these were actually Gen3 NA, but didnt take much to machine the turbo drain and tap some threads)
being a gen3, the stock oil filter location changed. using the NA oil cooler, it was all bolted up to fit. a High flow impeller waterpump was fitted to help keep things flowing..
before the block was put back together, the crank was checked. by chance i had a perfectly good Gen3 crank that had bearing numbers :00000. thats almost perfect when you do the checks. plastiguage confirmed the tolerances were spot on for ACL Black bearings.
everything was torqued down and checked over and over.
when it came to the head, we nearly put the spare Gen2 GTE head on. we had all the bits for it as it was..
but thats going backwards..
Gen3 NA heads are very close to the spec of the Turbo Gen3 heads. the difference is the Cams. they run higher lift and slightly longer duration than the turbo. in the Celica world, you use two gen3 NA inlet cams. its the same spec im running in my own Turbo gen3 build.
3.gen 3SGE M/T (180ps):
In: 252deg, 9.8mm lift (timing 7/65)
Ex: 240deg, 8.2mm lift (timing 53/7)
the head needed tweaking. to fit the side feed injectors (540cc), a 17mm drill was needed to bore the injector port out slightly to take the stock seals. and a tiny bit of casting needed grinding to allow for the rail. otherwise it was all good.
the valves were cleaned, stripped, lapped in by hand, and then each shim was checked over and over. i got them to the lower end of the OE specs. really happy with how they feel.
I ended up sticking my old Gen3 inlet manifold, throttle, stand and induction joiner onto the build. all coated in ceramic VHT gold.
Craig had a CT20B on the car already. its not perfect, has a bit more in/out play than i would like. but its been rebuilt once already. we are aiming to upgrade it later next year to a GT2871. they work great for mid power setups.
all the gen3 pipework was fitted, coolant tree etc.
the cam cover is a Gen3 NA which breaths into a GReddy Catch can. the cover is done in wrinkle blue VHT.
all genuine Gen3 Gaskets have been used on the build. although i did use a cometec 1.1mm MLS headgasket. Metal flanged deformed top locking nuts have been used on all the manifold to turbo to head parts. no chance on those working loose..
of course now the engine is mostly Gen3, it was time to pull the loom out the engine bay and replace it with the Gen3 loom. although it had been modded for a standalone, it didnt take much to revert to stock wiring setup for the Gen3 ECU.
this was the same ECU and setup that i had 327hp on the Dyno with the CT20B wound up on boost. so i have high hopes later on for this setup.
First two sessions of bedding the engine in were completed last week, it was then checked over, few minor tweaks before being driven yesterday. turbo is set at Actuator pressure. which is 7.5psi. no need to raise it just yet. once its had 500 miles of tame driving under its wheels and a change of oil/filter. then we might start tweaking the boost. somewhere i have a HKS boost controller around...
first impressions though, she is smoooooth. you can feel the power behind you wanting to go.. but even just trotting around at lowish speeds, not putting any harsh load on the engine, its a real smiler..
the Gear stick had been fitted with one of those eBay quick shifters.. it was crap. flopped all over the place. couldnt get gears. i fixed that with some welding and adjusting of the cables and plate. its a really nice feel when changing gears now. Atomic vomit Ceramic bearings on the gearbox end of the cables helps too.
currently running in on a NAPA 10/40w engine oil. but before it goes back to the owner, it will be changed for Valvoline VR1 oil. its got a nice high zinc content which helps with things like turbo bearings and heat. plus it has a nice smell.
really look forward to giving it back to Craig on saturday.
still a few tweaks to do though.. get it through the emissions is the key one. but that was kinda my mistake. used the old ECU Coolant sensor and original O2 sensor. both of which are around 30 years old now. two new ones will be here first thing. O2 sensor wasnt doing anything when heat was applied with a torch.
then once its passed, i have the undertrays to go back on, sort a couple of brackets for pipework. maybe a nice custom stainless exhaust heatshield. thinking of using a cabin blower fan for added airflow in the engine bay. i have one that shifts a ton of air.. way more than the stock intercooler one.
