AE25

onto my own wee project. was originally considering a non intercooled SC setup so that the sc was a simple bypass in the pipe between intercooler and engine. i was hoping that a low 8.0:1 compression ratio and water injection at higher temps would be sufficient to stop any chance of detonation on a lowly 10psi from the SC. my current 3tgte ct20 in the ke70 coupe creeps up to 13psi non intercooled.. and i know how damn hot the intake pipe gets just from heat soak alone.. thankyou toyota for 7.8:1 compression and 10:1 a/f haha. hmm wander how quick the intake air temperature sensor is to read the constantly changing air temps! this could be an issue so a fully intercooled system always going to be better original planned like this: after having a good look at the piping of that twincharged evo9 in Colorado with a friend luke (also looking into twincharging, but with an sr20ve 160J SSS coupe) we figured a way to intercool both chargers without too much complication or clutter in the engine bay. by entering the intercooler from two ends, and all piping can be kept low for appearance sake :P pipe from turbo to supercharger tucked away behind bottom of radiator. This system has longish pipes before the supercharger but shortest possible piping after which should help with supercharger response, and who cares about turbo lag as we're already on boost woot! on the water cooling side of things.. the 20v water pump could be used on a supercharged 20v, but with modified water intake pipe of course. I'm wanting to get rid of any rubber hoses if i can just for reliability sake. especially ones hidden behind supercharger! so the 16v 4age water pump and steel intake pipe suits my wants, BUT the intake pipe hits the supercharger if from an n/a 4age, whereas the supercharger one obviously doesn't. (pipe is bent differently). that in mind, rather than source gze parts which could be a bit more expensive to replace later on.. have opted to make stainless intake pipe and just a redtop 16v water pump.. something common woohoo

hmm interesting about the mazda/IHI blower! hey twincharger :wink: whats your name BTW. good to get your experience in this thread! I'm very curious how well the 'one way' valve works. have you ever checked to see when it opens and if it opens? the reason i ask is this.. you say you have turbo blowing into sc with a one way valve to bypass the sc when turbo comes on boost, but i see a reason why it may not open and that is, the sc will be providing boost which will hold the valve shut, then turbo comes on boost.. and say at one point in time theres now 1psi in front of the valve and theres 1psi blowing into the charger which compounds and always stays higher in pressure after the charger than before it and also the valve.. so the valve is always held shut? could this be the case? or if the valve is plumbed in far enough ahead of the sc that there is a delay in pressure rise before the charger than before the valve so that the pressure behind the valve is also delayed creating enough difference to force it open? could there be a combination of both where.. upon getting onto boost quickly it'll force the valve open, but a slow rise in boost will always keep the vavle shut? or am i just getting a wee bit too theoretical now heh. :P i like to throw theories around in the hope i'll understand whats actually happening when i get it running should it all go wrong! cheers

my thoughts on sc12 being 'restrictive' in a twincharge setup... yes when sc is before the turbo.. in which a bypass is required. In 4agze, i've seen sc12 flow enough for around 200rwhp.. 210 at the most on a 4age, using a bigger crank pulley to get 14psi or whatever the limit is before heat destroys the lobe coating. i've also seen improvements by replacing the std 4agze intake manifold (with the crazy dog leg #1 runner) for an equal length straight runner intake. (remember making an engine flow requires all links in the chain to be able to flow the same amount), the charger may not always be the restriction. But the main limiting factor of the sc12 roots charger is the heat generated at higher pressure ratio's. Just remember the roots charger is an air pump. it does not compress air within the charger like a lysholm twinscrew charger. it only compresses air when there is a restriction after it. therefore it works on a pressure ratio. the higher the pressure ratio before and after the charger.. the more work it is doing.. and the higher the boost and outlet temperature is. if both pressures are equal either side of the roots, then there's little or no load on the belt.. if atmospheric pressure either side.. then it's free wheeling. if equal amount of vacuum on either side (4agze at idle with ABV open) and it's free wheeling. 10psi on either side.. and its freewheeling. this is because it has a ZERO pressure ratio in these conditions. all it is doing is passing a volume of air from one side of the charger to the other. how this is relevant to being 'restrictive'... if a turbo is supplying 15psi air into a compound system and the roots sc is multiplying this by it's pressure ratio.. say 1.4, then with other influences like heat ignored, you'd be getting 27psi out. 30psi absolute x 1.4 - 15psi absolute = 27. now if the actual measured pressure was around this calculated figure (it's not going to be exact due to other influences) then the charger can't be 'restrictive'. it would only become restrictive if there is less pressure after the charger than before it. or possibly if the pipes entering and exiting the charger were too small to flow the volume required. back to the heat thing.. this is an efficiency issue, where at a certain pressure being produced, it creates too much heat... the heat is induced into the air from compressing it, and also made worse from the large lobe surface area conducting that heat into the lobes and passing it onto the incoming charge. friction from air passing thru the lobes could possibly be another heat creator all working together to cook coatings.. prolonged boost will likely cause damage rather than short bursts. But, say we give the sc12 some cooled positive pressure to suck on from a turbo, it then compresses this more due to it moving more air than the engine inhales, but doesn't have to compress it as much to make the same pressure as before, therefor not heating it as much... this means that it can now flow MORE air than it would by itself without melting the coatings off.. the incoming air temperature would have an affect on this, so the colder, the better. and why, even tho people may say a supercharger is inefficient... is beneficial in a compound system because the sc can provide more boost and make more ultimate power than the turbo alone. a turbo has an efficiency zone as well.. and beyond it's optimal efficiency it creates more heat, and has more back pressure in the exhaust manifold. The main point here is, the sc is NOT restrictive in a compound boost setup if the charger increases boost. My thoughts on mechanical loading of the SC belt.. when charger is running and has pressure after it, there will be load on the belt, same for if there's vacuum before it and atmospheric pressure after it. (set it up on a bench with an electric drill driving it, cover intake pipe and see that drill shit itself!). BUT, how much load does the belt really see if there is equal air pressure before and after the charger?? or rather, if there is a bypass valve that opens allowing air to recirculate or equalise, even at 5000rpm and higher. obviously there will be some acceleration lag due to inertia, like having a heavier flywheel fitted, but how much parasitic drag is there actually??? doing 200k down the back straight of a racetrack.. will you even notice an SC free spinning once the bypass valve opens? your acceleration rate wont be that fast that inertia is an issue (depends on application of course), but the parasitic drag of a loaded belt will affect hp and top speed. so i think this calls for a test run to see how much actual power is taken from the engine from a free spinning charger, a run with supercharger switched off at full boost from the turbo, and one with supercharger kept on with turbo at full boost (bypass valve open). So who's got a twincharger they want to dyno or do top-speed runs in aye! aye aye!

did you buy the w50 bell off myk00l by chance? i've once lined up a K-K50, K-T50 and K-W55 heh

ta22, ke2, ke3, ke5, kp6 etc use a further forwards shifter position than the later toyota gearboxes found in ke70 and late 70's onwards rwd toyota. the earlier t50 version found in ta22, te27 and a rare ke35 variant that has the forwards position shifter, but wont need to worry bout that in a ke70. my modded shifter on the rear position the 4 common positions... front ta63 + tt142 GT-T 3tgte w55, ma61? mid CE71 wagon W51 or W56 mid-rear 80's cressida's rear

i think you should change the poll to '4age turbo' just to clear things up... wasnt till i read thru the thread i found you were comparing ca18det to a turbed 4age. also 300rwhp or crank hp? my opinion is since the ca18det is already a turbo motor.. you'll have less issues/time setting it up. there should also be plenty of info on how to correctly modify them for the power you're after. 4age turbo requires custom parts to setup which could be quite costly if you don't have the skills to make yourself. how much do you know about the various 4age? knowing which are the better parts to use can save you a breakage and make it more reliable. ie use the later 7rib block if you can, which has stronger internals than a bluetop bigport and oil squirters up the piston bores to cool the underside of the pistons. biggest rods are in the smallport n/a or some of the red/black bigport engines.. along with the ae92 4agze. hard to say exactly what has what as there are too many variations. find some comparison pics to be sure. silvertop 20v have same rods as the ae101 smallport gze and although are smaller than the earlier gze, are ok for turbo use. gze pistons can handle a beating and can buy new for reasonable price so I'm told. 300hp on n/a pistons is asking for breakage, too much compression etc. starting with a 4agze would be a great start :P don't bother trying for 300hp if you have bottom end bearings that've done 150+ k's. for reliability sake have new bearings fitted with the correct clearances. getting 200hp from a turbo 4age is not hard. 300hp will require a bit more thought to the parts used and their flow properties.. turbo, intercooler, injectors, fuel pump etc all have to be up to the task. and i hope your using a programmable ecu to tune the thing! you got a budget in mind? haha you could build a 300hp motor by putting a t3/t4 on a n/a 4age and tuning it out of detonation ranges.. its been done plenty of times.. but at the sake of reliability and drivability. if i were doing it on the cheap, but keeping it reliable .. id get hold of a redtop smallport or silvertop 20v block and fit gze pistons, convert to rwd, make sure the bottom end is in good condition, put your desired head/intake on it, and build a turbo system capable of flowing the hp you're after. but don't scrimp on tuning it with aftermarket programmable ecu. this alone will add a heap of reliabilty when tuned to safe air/fuel ratio's. doing it on the utmost lowest budget.. use a cheap 4age and put your turbo stuff on it.. eventually when it runs a bearing or cracks a piston crown.. buy another cheap 4age and swap your bits on it and go for a while more. heh heh um hope that helps if you didn't already have that kind of info. ps don't believe everything you read on the net

well said!! taking on v8's huh :) the benefit of quads is throttle response.. they not going to add a heap of power to a stock engine, so expect to be a lil disappointed.. nice on a twisty race track or mountain pass, but not always going to win straight line drag races against modified bent 8's. a turbo will definately gain you the most grunt. a supercharger would be less hassle but ultimately not a quick as a turbo. consider you'll want to install and have tuned an aftermarket ecu to make use of the quads or turbo. without that, you wont see much benefit of the quads or reliability with the turbo. the quads will need an aftermarket or custom intake manifold.. so that could be a couple hundy to start with. turboing is a whole different story and will cost a lot more... custom exhaust manifold, dump pipe, bigger exhaust, oil feed, oil drain, the turbo itself etc and thats just to bolt it on. then the ecu and tuning so it doesnt blow up. you'll want to replace the bottom end bearings if they a bit worn as they don't last long with high km's on em, especially the bluetop. may have to improve the radiator efficiency.. add an intercooler and bov if running above 8psi. you could do it all on the cheap with 2 grand for sure.. gze efi, second hand turbo with home made piping etc but don't expect total reliability. sorry if i sound like a pessimist.. i just see too many 4age turbo's go wrong

if you're looking into efi and turbo.. consider finding the 3t-eu efi intake for your 3tc since you've already put effort into a rebuild. and buy/make an aftermarket turbo exhaust manifold if you can afford it. 3tgte turbo system will bolt on the 3tc, but the std exhaust manifold is prone to cracking and the turbo are pretty crap anyways. i plan to do this for a bit of fun http://www.toycrazy.net/tech/3tte/3tte.html 3tgte are pretty old, but with a freshen up and a few mods.. they're great. if you buy one that hasn't been rebuilt... add a rebuild into the cost of buying one as it'll leak oil for sure and be a constant maintenance headache if you plan on driving it hard. i know this from experience :)

there are 4 common shifter positions that can be found on the supra alloy W box W55, W57, W58 etc. and there will be at least two that should line up with the ke70 hole assuming you're using te71 crossmember/mounts. you are able to swap the shifter housing and selector fork to get the correct position. i've had in use 3 of the shifter positions in my ke70.. the rear most one i reversed the shifter 180deg and bent it backwards again.. but the middle two will be closest fit. T50 from 80's era will line up too. hope your not thrashing it too hard.

3tgte came fitted with a W55 it will bolt to the engine obviously with the 3tgte bellhousing. 1G, 1GGE, 1GGTE W bellhousing also fit a 3tgte but the clutch is on the exhaust side so will need longer clutch line and heat sheilding over the clutch slave (maybe mod exhaust to fit around it). the clutch and driveshaft are bigger so will need to swap/mod these too. shifter position may be different depending which car the W55/W57/W58 came from. also the gearbox mount is deeper, ie it needs a lower platform to bolt to so gearbox crossmember mods required.

W55/W57/W58 or W50? much difference between them! a wee list for ya.. convert to hydraulic clutch. may possibly need massaging the gearbox tunnel? change to a 21spline W box driveshaft. grab a corona shaft from behind the W box and shorten it or an auto corolla or celica one. (check the uni's are big enough). trim the shifter hole to suit if the W box shifter is in a different spot or find the correct shifter position. use original speedo cable.. but swap in the correct speedo drive gears if the speedo is out of calibration. swap clutch plate to one that fits the W box. they got bigger input shaft than T50 ps.. for those that don't know... T - W50 steel case is slightly smaller box but heavier.. tho more common to find a bellhousing for as they come behind 70's model 3t powered corona's etc T - W55 alloy case only ever came fitted to a 3tgte or 3teu in jdm ta63 or tt142 so good luck finding bellhousing

have a flick thru these pics! 4k-ze ke70 crackup seeing blown bits after the conversion http://www.romut-radalle.com/viewgal.php?gid=248〈=en

oh and for you left hook drivers.. this applies to RHD!

got your reading glasses on ;) (hope your not dyslexic) :) most parts will bolt over to the new chassis but that all depends which model E7 you have. what's required, depends if your ke70 has a rack and if it is a wagon or not. all te71/te72 have recirculating ball steering NOT ALL KE70 HAVE A RACK! if your ke70 has recirculating ball R/B steering it makes it easier to fit the T series engine. the other thing that definately needs mods is the firewall.. as the T50 5speed gearbox uses a hydraulic clutch.. and the pedal box is different than ke70.. you need to drill/cut 3 holes in the firewall next to the brake master cylinder for the hydraulic clutch. you will know where to put these with the te7# pedal box bolted up.. you will first need to drill one hole to let the clutch master mounting stud poke thru the firewall. if you have a rack in the ke70.. keep it! easiest way to do it (and looks factory too) is either # cut the engine mounts off the ke70 engine crossmember and cut/weld the te72 mounts on there. or # cut the rack mounts off the ke70 crossmember and weld onto the te72 xmember. when using a rack with a 2t/3t engine you need to remove the gearbox brace that bolts to the engine block as it contacts the rack. also rear of the 3t sump will contact a tiny bit on the rack mount. give the sump a wee beating or section if you need to. the driveshaft varies depending on which gearbox and diff you have. a 3t will most likely have a 22spline T50 (count the output shaft splines where the driveshaft fits in). up to about 1982, the te71 2t and 2tgeu had a 20spline T50 which will fit the std ke70 (K40/K50) driveshaft. some 1983 te71 have a 22spline T50 like the te72 3t (and '83+ ta61 2tgeu, tt141 3t etc). so you could theoretically bolt the T engine a T50 in without changing the driveshaft or diff. A 22spline T50 will need the te72 driveshaft if also using the te7# diff. otherwise you'll need to have the driveshaft cut/weld with a 22spline yolk on the front. Different sized diffs have different length driveshafts.. a bigger diff has a shorter shaft. your te72 shaft will be shorter than the ke70. te71/te72 diff will bolt into a ke70 sedan, liftback, coupe or hardtop but NOT a wagon as they have leaf mounts. if you have a whole te7# as a donor car.. swap the diff and front struts together so it doesnt affect your brake bias. the te7 diff will likely have bigger drums therefore if you only swap the diff.. it'll bias the brakes to the rear so they'll lock up earlier than the front which you don't want. you may be able to swap the ke70 drums to the te7# diff? or install an adjustable brake bias valve. if swapping in both the te7# struts and rear brakes.. it may help to swap in the larger te7# brake master cylinder too if its not already 13/16 size. Swapping struts... you don't have to mod anything to swap te71 struts in, just swap parts round to suit your car.. you'll need to use the te71 steering arms (knuckles) as they have a different bolt spacing to bolt to the strut. this may then cause an issue with steering arm length if you have a rack.. because ke70's with rack often have shorter steering arms than te71. there are other arms available that are shorter to suit tho. also... 79-82 ke70/te71 etc have equilaterally spaced bolts on the strut top-hat (at the top of strut).. '83-'88 E7 have unequal spaced mounting same as ae85/ae86. use which ever one fits your car. ie if the struts you're putting in are different.. take the ones off your original ke70 struts and fit them to the te71 struts. the springs on te71 struts should be stronger to account for the extra weight of the T engine. if you use the ke70 struts/springs and your front end drops a bit lower when fitting the 3t... you'll know why heehee the wiring looms are a little different but not heaps between ke70 and carby T engine (efi is totally different). and also may have different holes in the engine bay that they come through. use the te7# loom if you can as it'll have all the correct lengths of wire etc. you may need to cut extra holes in the engine bay inner guards for it... and take your dash out to fit the loom under there.. it takes a little while.. and if you do it make sure to label the plugs when you unplug them from te72 so you know what they connect to later on. early and late E7's have different plugs so if you're changing between the two.. you may have to swap the heater fan, guage cluster, heater control panel etc so the plugs match up. sedan and wagon have similar dash.. whereas liftback, hardtop and coupe are similar to each other. so can't swap dash/instruments between say a sedan and liftback due to different dash shapes. then theres the radiator, exhaust, ignition etc.. use all the te71/te72 stuff Hope that helps!!! i've been thru all that conversion stuff before in my own ke70 so if you need to know anything, fire me a PM. I wrote this also.. so have a read. it should clear more things up requarding fitting 2t/3t into a ke70 http://www.toycrazy.net/tech/KE70-2tgeu.htm tho i went from a 4k, to a 2tgeu, to a 3tgte

I see benefit in 3 twincharger systems. none of which are running the chargers in 'parallel' which seems to be the first thing people think of doing! the problem with a parallel system is the supercharger is trying to blow back out the turbo until the turbo sees enough exhaust flow/pressure to spool it up. yes you can fit extra valves and flaps to bypass and divert air but it will only ever increase turbo lag and add complexity. so i think.. why bother when a 'sequential' or 'in series' twincharger system has been proven to perform :D the 3 systems are... #1 turbo into S/C continuously. as described previously. This is by far the simplest way as it does not require bypassing the SC or turning off s/c at higher rpm. the supercharger sucks it's air through the turbo which gives bottom and midrange torque.. then turbo comes on boost and blows into the charger (compounding boost) for top end power. A higher total boost pressure is created compared to sequential systems due to the compound effect. the turbo's wastegate controls total boost pressure. Ideally run two intercoolers, one after the sc and one after the turbo. It needs to be mentioned that this system must run a sufficiently sized recirculation valve on a positive displacement (roots) charger. The air flow through the roots needs a way out if the throttle is shut. The consequences of not bypassing air can be blown piping/gaskets or worse a bent/broken throttle shaft (uncontrolled full throttle and full boost is potentially fatal if occurs at the wrong time!). Also, feeding a sc hot (non intercooled) air straight from a turbo could cause damage to some sc if the sc's pressure ratio is too high. For instance the toyota sc12/sc14 have coated rotors which can melt/delaminate at high temperatures. anywhere above 14psi (boost created by the sc only) can create enough heat to do this. If you run a single I/C after both chargers, the hot air from turbo will add to the heat made by the sc, so a decrease in sc pressure ratio (smaller crank pulley) will likely be required to keep heat under safe levels. This is also required to get a good balance of efficiencies from both chargers. 8psi sc / 15psi turbo etc. Intercooling and/or water-meth injection before the sc is a good idea. Cameron-datto on toymods forums runs this system in his sc14 4agzte 1200 datsun. #2 turbo into S/C with bypass. (Nissan March superturbo and HKS 4agze twincharger kit). The sc provides low rpm boost until turbo matches it for flow. a bypass valve around the sc is gradually opened until the turbo provides all the air. once the turbo out flows the supercharger then the charger can either be left free wheeling or disengaged via electromagnetic clutch. The bypass valve operation is the crucial bit... it's the GRADUAL opening of the bypass that is essential to a smooth transition from sc to turbo. the bypass valve is set to start opening at anything *above* atmospheric pressure before the SC. The idea here is that the turbo will be matching the flow of the supercharger at the point when pressures balance out, measured before the sc. You will then need to be able to control the rate of valve opening in relation to turbo boost pressure. If the bypass too slow to open it will act like a compound system. you will want a measured amount of this but if the compounding pressure exceeds the maximum overall boost pressure then a spike and resulting drop in pressure will be seen once the switch to turbo is completed. If the bypass acts too fast there will be a pause or dip in boost pressure. the perfect boost curve is one that raises gradually without dips or spikes. Under full acceleration, (going by other peoples experience), the turbo spools up quickly and the bypass change over period happens fast. A poor changeover is not so apparent under full acceleration but shows it's ugly head under other conditions. The downside of this system is more complexity, more components, more expense, more space used. A single intercooler system can be used... 1: cooler after turbo.. a low pressure ratio on the sc should keep temps down enough not to require intercooling. The IC needs to be efficient enough to reduce temps entering the sc for safe operation and reliability. 2: cooler after SC.. Turbo boost pressure (heat) needs to be low enough not to overheat the SC. This could kill the benefit of a twincharger system in some setups. Other options to reduce air temps or knock resistance are to lower engine compression ratio, water/meth injection, better cooling systems, cam adjustment to reduce valve overlap (turbo boost only). if engine is already built then you're left with tuning, ie reduce ignition advance and richen fuel. Throttle BEFORE the sc.. as used in factory 4agze engine and HKS twincharge kit. This takes away the danger of blowing things up if the sc recirculation valve malfunctions. It's also quieter than throttle after sc due to blocking the noise from charger inside the intake pipes. throttle before sc is the safer option if only a small intercooler is required for the SC and short piping can be used. Throttle before SC does not suit a big intercooler and long plumbing. Increasing the volume of intake tract after throttle and before engine increases sc lag. Along with that, it creates a potentially annoying ability to continue accelerating for a second or two after throttle is released. Any leaks in the supercharger's intercooler or piping is also a big issue, due to air bypassing the throttle. Instant redline from a burst pipe at the wrong time is not good for the health! :o #3 SC into turbo with bypass SC blows through turbo until turbo matches it for flow then a bypass around the sc or from a separate air filter opens to free up intake air before the turbo. otherwise the sc will restrict air entering the turbo. A single intercooler setup is used, both chargers are before the cooler. The bypass valve is also a crucial part and needs careful calibration on opening rate to prevent any dips in the boost curve. If bypass opens too slowly, the turbo sucks a vacuum into the piping before it (after the sc), thus restricting air flow to the turbo and reducing power. Also a vacuum created before the turbo compressor can cause oil leak issues and increased thrust bearing wear. If bypass opens too early, ie before the turbo matches flow rates, you'll get a dip in boost.

re the HKS 4agze kit problem (first ive heard of this). i can only assume this is happening due to it retaining the factory 'throttle before charger'. if bigger intercooler and piping is added i could only assume that extra volume between the throttle and engine is causing this? ie say (after the throttle) you've got 10psi feeding thru a big front mount intercooler.. after you back off the throttle.. that 10psi of volume needs to be sucked thru the engine before the engine sees vacuum so it can slow down again :o

thanks guys :) yeap the more I'm researching into twincharging the more i'm getting interested in it. i've read thru countless forums and the amount of bullshit theoretical info is incredible :o i'll probly have to edit some of what i've said but meh. soo.. to add more to this thread: Most superchargers (ie roots type) will require a recirculating circuit or air release system that operates when the throttle is shut.. used when engine at idle, when braking or between gear changes. the air that the sc is passing needs to go somewhere otherwise bad shit happens... belt slip, popped piping or blown intake gaskets/manifolds! Toyota use an Air Bypass Valve (ABV) in their 4a-gze/1g-gze/1kz-fze(?) engines which operates via a diaphram connected to intake plenum and also controlled via an ecu controlled solenoid. more info on that here http://www.mr2supercharger.com/ABVmods.html To explain the ABV: when supercharger is engaged and throttle is shut, high vacuum in the plenum pulls the abv open creating a recirculating circuit through the SC. once throttle is pressed.. depending on intake vacuum the ABV gradually closes which directs more and more air into the engine until the ABV is fully closed creating pressure in the intake plenum. as you back off the throttle, the intake is under vacuum again which open the bypass circuit allowing the charger to spin freely. the ABV is held shut by a spring rated at the maximum boost pressure which will allow the ABV to open once full boost is reached (8-10psi in factory 4agze system). this is a safety mechanism to relieve any overboost. The toyota system also has a time delay (5secs?) of full vacuum before the charger is disengaged via the electromagnetic clutch (so it doesn't cut the SC whilst changing gears etc). The clutch is re-engaged at 8" of vacuum, ie when throttle is pressed. The best bypass/recirculating valve to use is an external wastegate off a turbo as these use a diaphragm operated valve which is smooth in operation. (tho expensive) an external wastegate measures the difference in pressure before and after the throttle. The air line connected after the throttle is attached to top of the wastegate actuator so it pulls the valve open.. the air line before the throttle connects on the underside of wastegate diaphragm so any pressure before the throttle helps open the bypass valve. Unlike a BOV (blow off valve) which is designed to open and close suddenly and harshly which can cause flutters and other issues so is not suited as a ABV. Using a BOV solely to release air to atmosphere from the SC system is both noisy and a waste of power/petrol. imagine your sitting at idle and your engine is constantly pissing air! it WILL get annoying. A BOV is still required when using a turbo.. and in a twincharger system, when used in conjuction with a ABV will only open when the tract after the turbo is under pressure. ie when the ABV is open there will be no pressure in the supercharger circuit to cause the BOV to hiss air. (a plumb back BOV could be a solution to this if noise is an issue) i think some explanatory diagrams are required here :D

WOW dude i'm loving your mods! that modified 3sge intake looks very well fabricated and still has nice long runners for good midrange torque ;) most of my questions have been answered already.. keep it up! multi coil ignition is awesome! hopefully we see some more toy phreaks getting into the 3sge conversion! i vote for you putting up a 'how to' on making your 3sge rwd intake!!!! your question about the steering arms (or knuckles), te27 arms are most commonly sourced in the states.. when ever someone asks to buy something from me i reply with 'can you trade for some te27 steering arms' heehee. te21 and te28 have the same arms just so you know. trading like that has scored me some so it works a treat :( but in saying that.. if your having trouble with lca contact on the ae86 arms with st141 struts/pug disk, then you'll probly have the same trouble with te27 arms. if i get a chance i'll dig some out and take a pic for you (the arms). Other options you could look into is using mx73 cressida hubs.. which are all the same as st141 hub, but have a thinner hub where the disk bolts to.. so the disk sits outwards about 5mm or so (email me if you want me to measure exactly) it seems only the Mx73 has this.. gx71, gx61, ta63, ma61 etc have the fatter disk mount. (saves you machining them thinner). you'd have to space the caliper out accordingly too... which then gives you less options for wheels as most will hit the calipers. ive played round with a heap of parts and found 4pot hilux calipers a pain to fit if the disks aren't offset in enough. please double check the two bolts at bottom of st141 strut are 90mm apart! not 87 or 85mm otherwise discard the above info.. the cressida hubs most likely wont fit 85mm or 87mm type strut :) Another option is offset RCA's. i don't particularly like the idea due to it being similar to sticking overly wide wheels on which if you've ever had 13x8's on the front.. gives a twitchy feel to the steering. T3 (amongst others) sell them for ae86 (85mm) Or you could probly get some made with two different bolt spacings to suit the steering arm/ strut combination your're using.. like say ke25 steering arm (80mm spacing) to st141 strut (90mm spacing). also ae86 steering arms are 85mm spacing. i noticed earlier it was stated as 87mm. 87mm is the ke30 or earlier ke70 steering arm-to-strut bolt spacing. i have made a list in comparison here http://www.toycrazy.net/tech/struts.html keep up the great work! I'm certainly keeping track :)

my best in ke70 3tgte is 14.59 @ 95.6mph stock engine w/ 2.5" zaust n locker best time in ke25 4age is 15.7 @ 87.4mph clapped out n single spinner woot

how bout a 2rzfe rwd 2.4 4cyl dohc efi.. so some head work and cams for a midrange grunter or even turbo it or how bout some of the newer fwd n/a engines coming out.. the 2zzge is a performer yet relatively unknown in rwd conversions

yep pretty broadly put there bud. be specific in your questions. heres my own spot on the web on a 4age'd ke25. http://www.toycrazy.net/mark/KE25.html it's about to be rebuilt a whole lot better but may give you some tips on what in involved. also google lachlan's 4age ke25.. he's put a few fuel systems etc on his page as to setting up the 20v in rwd format.. i suggest a look in www.club4ag.com technical forums under 20v. theres a nice big post on how to convert the cooling system to suit rwd and alot more.. distributor modifications, intake plenum reversed etc

after looking into it further.. the water system of the 20v with supercharger needs to be totally rerouted. you could mount the charger further away from the block to retain factory 20v cooling system but most rwd conversions will be out of room. using the factory 4agze bottom mount and pulling the charger up close to the quads, theres just enough room to squeeze the water pump inlet pipe past the sc to a remote thermostat sitting behind the charger under the intake. the factory 20v head-to-waterpump pipe will not fit. is a bit too much of a squeeze to get even a custom pipe made to fit without it going down past #3 cylinder and back to the front. no reason this couldn't be done but will have to also move the vacuum piping under the quads for enough clearance. there is a limit to how close the charger is mounted to the block due to the knock sensor (in pic)(edit.. have found gze have knock sensor fitted between #3&4 cylinder rather than #2&3 as found in smallport 16v and 20v). the std sc12 bottom mount had to have the rear bolt hole milled 8mm off the underside so it mounted flush with the block with an ae86 engine mount sitting underneath it. a custom engine mount could otherwise to be made to bolt on top. what I'm looking into doing now is have a manifold off the back of the head that joins the two holes together (rather than grind a water passage out of the back of the head and weld the holes up) so that the hot water coming out of the block goes thru the head under the quads and out the front hole above the water pump... this is then the hot out to the radiator and has enough room (if you design the top sc mount to fit around it). this should also get rid of any possible airlock problems that could be caused if the hot out were to come off the back of the head and then down under the charger etc. hot out should stay high so all air in the system can easily get to the radiator. it would look something similar to this awesome drawing from this to this

the top guide is usually fine to reuse.. the one on the hydraulic tensioner is often the worst. check the underside of the cam cover above the cam pulley area. the rattle could be the chain hitting the cam cover from either slack chain or not using the rubber gasket which is about 2mm+ thick.

also 3tgte have the same chain and chain guides as 2tg. i have ordered new guides through my local toyota and the part numbers are 2tg 88220 spec ie the very first 2tg. as to availability I'm not sure anymore as this was a year ago and toyota have recently stopped listing the A6# model celica's where most 2tgeu/3tgte parts come from. chain guides retailed around nz$220ea ex japan :dance: and theres 3 of em

there are power steering models of the ra60 ra63 ta63 ta61 aa63 etc that have a steering arm (knuckle) with center to center length of 125mm and strut bolt spacing of 90mm. the ball joint hole is same as ke3 up to ae86. these are the shortest i've come across for the 90mm type strut bolt spacing another option is get those offset RCA 'roll center adjuster' that convert 85mm steering arm to 90mm strut and adds more camber and track width. use ae85/ae86 steering arms which are either 135mm or 115mm. our late type ke70 have a 130mm long arm over here.