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Where to start - well a new engine is in a million bits on the workshop bench ( went to by a rocker cover - came back with a 1992 Applause HD engine ). Is undergoing a complete rebuild from the ground up - forged pistons, balance, port and polish, cam etc etc etc and of course the supercharger. Much easier to do it all on the workbench than in the vehicle. Will be interesting to see how it goes, was going to be mild, low boost - but what the hell now its going to be a screamer. Don't know if you got the Applause in the US but some models use the same HD engine as the Feroza ( with different accessories ) so it makes good spare parts. Got a bare engine ( in excellent condition - almost too good to pull down ) for $100 AU and appart from no flywheel ( it was an auto ) gives me all the bits for a "take it easy" rebuild. just be aware there were also 1.3 Litre versions which look the same but obviously have different internals. Go a lot of rubbish stories from 4WD wreckers about second hand engines, but the Applause HD is the same base engine and so will go in. Fitted extractors to the old engine, and its a very worthwhile exercise. The existing engine is far from new, but the exhaust made a usefull difference - mostly in driveability. Its coupled with a 2.25 Inch rear pipe which is overkill stock but is designed for the hot engine. The only minor issue is the extractor flange is a little off position from the stockie and the exhaust now knocks on the chassis - something thats annoying and needs fixing. The engine design seem OK in general, however the rods are a little small for big power and the finish of the head leaves much to be desired. There is undercut under some of the valve seats and shrouding of the valves by overhanging metal on the head. Will flowbench and re- machine the head to see what happens. Metal removal is not a problem as I want to drop the compression to around 8 to 1 from the stock 9.5 and between the pistons and head should be no problem - however this would not be great for a normally aspirated engine, the head would need to be shaved to get the compression back. Also put the Applause distributor in to see what would happen ( my HD would ping very easily ) and its much better. Will trace down the curve when I get more info and see just what the difference is. So far parts have not been a problem - with NO parts bought from Daihatsu ( they are pigs to deal with in Australia ). Don't know how interested people will be in a rebuid story, and I don't claim to be a racing engine builder, but don't mind putting a few words together. No going to rush the rebuild so its a ongoing story.
Even after Cam, Extractors, Ignition and EFI mods the Feroza still is a bit down on power ( the engine isn't new - around 200,000 Km. ), so thoughts turned to a power up project. Whilst an engine swap is possible, it makes for a whole pile of vehicle engineering and registration issues that can be a hassle to work through ( at least in Australia ) - and hard to undo if there's a problem. So the next option was a power up on the standard engine - which involved either turbo or supercharging as normally aspirated really doesn't have the potential and would make it much less usefull off road. As I have 31" tyres and suspension mods already - low end torque is really required so the turbo option was looking less attractive ( its possible of course and would be good for mostly road use ). The other deciding factor was I already had a Toyota SC14 Blower and no turbo that was suitabe so that clinched it. The concept was to supercahrge the old engine and see what happens, but finding a Applause HD engine at the wreckers for $100AU convinced me to leave the old engine alone ( the Appluase engine had done 32,000Km and was in nearly perfect condition - almost too good to rebuild - but thats another story ). So now I have an engine to work on, a blower and the urge to build a decent engine...... Before I get into the real "stuff" - a few bits of info and a request for tolerance..... I am not a professional engine builder or even a mechanic for that matter, however I have been involved with vehicle engineering and motorsport for many years, so I have a "reasonable" knowlede of how things work and what to do. For those of you who are experts, please cut me some slack, this is not an unlimited budget project so there will be the inevitable compromises and disagreements on the what and how bits. As I pay the bills - I get the final say. So the engine got dismantled and the inspection process started. First observations..... The Engine is an interesting mixture of "not bad" and poorly finished. The things that hit me at once were : Bad things..... - The combustion chambers are poorly finished - sharp edges everywhere
- The head gasket hangs out into the bore / combustion chamber
- The intake and exhaust valve seats have undercut so flow could be improved.
- The Conrods are small - which could be a problem.
- The intake manifold plenum is too small and probably doesn't flow well.
- The oil drain back passages from the head were very restriced by casting flash
- The gudgeon pins were poorly finished internally - and different weights.
Good Things..... - Port area isn't bad for the engine size
- Crank isn't bad ( and has hollow journals. )
- Quality of block casting was good.
- No unnecessary complexity - a simple, straightforward design.
First steps Cleaning and cleaning and....... The crank and rods were crack tested ( magnafluxed ) and checked out ok - no point in doing work on damaged parts... Block measured, just to make certain that it hadn't been worked on before and had as much metal as possible in the important places. Parts availablity checked ( yes I know that should be done before ) - can get everything I need from aftermarket sources. The major issue so far is the conrods. They are just too small for my liking and the rod ratio could be improved. The big end bolts also worry me. The problem is of course what to do about it - there are no rod bolts available for the HD ( in fact couldn't find Daihatsu listing anywhere ) so may have to use something else. Closest is Unbrako Cap screws at 180,000 Lb yeild but is short of the 220,000 Lb for my usual ARP rod bolts and the head shape is not even close to the oval headed stock bolts. May have to use stockies.... A set of stronder substitute conrods from something else would be great and as I will have pistons made the little end is not an issue. But its difficult to find data on conrods, perhaps someone has a database or book but not me. The key criteria are big end size and rod length. If you know of a substitute ( and not custom made rods as thats too expensive ) please let me know! So this stops the bottom end build for the time being - until the rod issue is resolved no point doing anything to the bottom end / rods / pistons apart from cleaning up the flash on the crank, which isn't too bad anyway. The next step is the top end.
Issues with the standard cylinder head. Undercuts under valve seats…….. 
Whilst I have seen Devcon ( a filled epoxy resin ) used I would grefer to remove the seats and have the Head built up and remachined.
A strange "hole: in one of the intake ports…… 
Its about the diameter of your little finger and is machined - but doesn't do anything !
Once again a weld up job.
Sharp edges in chambers 
A workover with a die grinder will fix this
Oil drainback to sump ( forgot to do a before photo ) 
A few minutes with a small file opened these up to what should be… As delivered about
50% of the drainbacks area was blocked with casting flash. May not seem an issue but
I have seen a number of HD engines where there was almost a solid lump of carbonised
oil clogged around the valve gear. You have to see it to believe…..
Lubrication System. The HD lubrication is simple and very conventional. The pump has been checked for wear / scratches / clearance and is in good condition.
Will shim the pressure relief valve a little to get a slight increase in oil pressure given the higher stress things are likely to be exposed too. The oil pressure switch is on the pump side of the oil filter, which isn't perhaps the absolute
Ideal place ( the engine side is better ) which means that tapping off the switch for an oil pressure Gauge ( electric - as I don't like running small oil lines all over the vehicle ) isn't great, and there's very Little space around the switch when all the engine extras are fitted. This space issue prompted me to look at the oil filter ( no longer dead easy to change as the supercharger Is no on to of it ) and more importantly oil temperature. Given the blower is going to add to the engines overall heat load an oil cooler would be a very usefull extra. Deciding to bite the bullet - I have made a remote oil filter system that has an adapter that screws on to the standard filter mount, and a remote base for a filter. The oil cooler can of course be plumbed into the hoses. I have used 1/2" BSP fittings and lines, which is probably overkill. The oill pressure sender screws into te remote adapter so actually indicates true engine oil pressure and Solves the "no space" issue. Note the engine is standing vertically on the bench so it looks "strange". ( The weird bracket behind the filter is the supercharger mount ) 
I have not decided where the remote filter will live yet but as its on hoses I have a number of choices. The oil cooler location is a bit of a problem also. Before the winch went in, I had a good space below the radiator whith air feeding in from above the sump guard - but now that’s blocked off. Will probably end up behind the left headlight ( a surprising amount of air passes through at speed ) with fan(s) for low speed work.
Hopefully the adition of an oil cooler will assist in keeping the thing cool with the extra engine load..
Flywheel and Clutch As my block came out of an auto it didn't have a flywheel fitted, and after a bit of chasing I managed to purchase one. Wanting to maintain its off road ability. The flywheel has simply been faced - leaving it as heavy as possible. The clutch however was another problem…. As the whole point of the supercharging exercise is to make more power ( torque actually )
A stronger clutch seemed like a "good idea". Having made quite a few phone calls to clutch specialists, things looked a bit grim - some
would modify a stock pressure plate ( which I didn't have ), but it was all very trial and error.
And without a stock clutch to work with, difficult to get started. And then the good news - a competition clutch is available AND one was in stock !
It consists of a Heavy Duty pressure plate and "Sports Organic" Driven Plate Here's the details…. Pressure Plate EXEDY Part Number DHC538HD
Driven Plate EXEDY Part Number DHD031U EXEDY appears to be a division of DAIKEN - Japan, a reputable supplier from previous experience The kit came with a clutch release bearing ( which has no numbers on the bearing - just to make replacement
Difficult ) but its an NSK - 44TKB2805BR ENSS 407.    
Being a non stock clutch a few "I told you so's" are required. As there are no cushions between the friction faces and the drive plate, clutch engagement will be less progressive. As the clamp pressure is higher, pedal effort will be greater.
The engage and disengage points will be different from a stock clutch
You have to put up with the horrible purple color………..
SuperCharger & Mount The Supercharger is a Toyota SC14 unit off a 11GZE 2 litre, six cylinder, twin cam, and displaces 1.4 litres of air per Supercharger revolution. So the blower is technically larger than needed…… Toyota also make a SC12 which is a smaller unit mechanically and in terms of output, but would be fine ( use what you can get ). As there are unknowns in blower drive calculations, I have started off with a design than runs the blower at 50% engine RPM. The blower is driven by a five row polly vee belt and is fitted with an aircon style electric clutch so it can be switch in as required. This sounds great, but if the blower is off, the engine cannot get air so a separate air system is required "off boost" which on Toyotas is a special bypass valve. Other manufacturers run 2 throttle bodies. As the HD engine is small, I may well run the blower all the time and forget the bypass valves etc…. Mounting the blower wasn't that hard once I decided to use an aircon bracket as the base. This saved heaps of time as the mounting bosses on the engine are all over the place and at different heights. The aircon bracket takes care of all of this. Obviously I don't have aircon On my Feroza… If you do then its your challenge as to how to mount the blower ( different - but not impossible )  The blower is out quite a long way so it will clear the exhaust ( extractors - not fitted to engine in these shots ) but actually fits quite well - all things being considered. And yes it does clear the bonnet and body metalwork without modification….. The brackers are 20mm al, which is overkill but I had it, so it got used. The top blower mount, which also serves as the belt tensioner, mounts on the front three rocker cover hold down bolts, which was about the only place I could find that was practical. Have used rod ends to permit the required angle changes, but an alternator style circular bracket would do the same job. Not happy with the bracket yet, its angle is too steep and will get in the way of the plumbing - but you can see the general idea. The Intercooler. Whilst I wasn't initially planning to use an intercooler in the first build, I realised that it would be wise to at least do some prior planning to make sure I didn't do anything that would cause later problems ( not big ones anyway ). Searching through the local suppliers and the internet it soon became obvious that I couldn’t get an air to air intercooler the right size to go on top of the engine and plumbing a front mounted intercooler would be very difficult. The cost of having a bonnet scoop added to feed air to a top mounted intercooler was also high - and its not a great place to mount one anyway as it makes working on the engine a real pain and at low speed doesn't do much anyway. The next option was an Air to Water intercooloer which was a little dearer than air to air
but ended up being cheaper overall. It’s a 200KW unit and is very compact
 
Not wanting to make tappet adjustments a major job and not having much over the engine space I decided to mount the intercooler along the axis of the engine. No matter which way the piping runs it’s a pain and has a few sharp bends - not ideal but……. 
The blower outlet manifold was heavily modified, its part the cast original and part fabricated and TIG welded. Its looks straightforward but it actually has to wrap around some protrusions so was a pain to make. Although not shown in the pics the blower and intercooler are joined by a 2.25" heavy duty silicone "Hump" hose connector. Worm drive hose clamps ar NOT used - they are not really suitable for silicone hose, but if you must - use rolled edge ones without the thread being cut all the way through. Band clamps are the answer as they have a larger clamping area. 
As the intercooler is too heavy to just be supported by its hoses, a padded mounting ring was made that goes onto some of the middle rocker cover bolts. As the intercooler moves with the supercharger as its drive belt is adjusted the intercooler mount has to be adjustable also. 
A BOSCH electric water pump will be used to circulate the intercooler cooling water through
an aircon condenser mounted in front of the radiator to get rid of the heat. A small header
tank will probably be needed at the highest point of the system to allow filling and purging.
Did a "test fit" of the blower into the Feroza just to make certain everything would clear ( and it did ). A pic for historical sake. 
Supercharger Drive The Supercharger is driven from the front of the crankshaft via an adapter/spacer and pulley. Those with keen eyesight will notice the stock pulley is "wrong" as it has two PolyVee
sections on it instead of the one PolyVee and one plain vee belt as on the Feroza.
Its an Applause unit and they must run PolyVee belts for the Alternator / Water pump.
Might be an interesting mod. 
The blower pully is a Toyota Alternator six row Poly Vee unit inset by one row as the
Supercharger runs a five row belt ( needs must…. )
An adapter spaces the Supercharger pully out by the required distance and takes care
of the multiple bolt patterns ( the Daihatsu crank pulley bolt pattern is asymetric )  
As there is limited room, socket head cap screws have had to be used, and it’s a bit of a pain to fit it when the engines in the car - but dead easy on the bench. The bolt pattern and clearances for the adapter to the crankshaft are reasonably tight to ensure the additions are on the cranks center line. The pully has a machined step and so self locates.
The mechanical engine fan and shroud has gone, replaced with an electric unit which gives
enough room for the drive belt, with some to spare for possible engine movement. Machined
the fan boss to remove the flange for the mechanical fan as its no longer needed ( a pain to do ) but looks better without it. I wouldn't advise a thick thermofan and shroud as it could easily get in the way of the Supercharger drive belt.
Supercharger Intake Manifold
The supercharger intake manifold is now virtually complete and has been test assembled - including the Throttle body.  
The coin sitting on top of the throttle body is about 28mm so you can judge scale. 
The cable horn from a stock throttle body was modified slightly to fit on the new throttle shaft and retained by a central bolt drilled and tapped into the new throttle shaft. This maintains the standard cable pull ratio. The cable needs to be lengthened substantially, and a bracket made, but that’s a later job. A few surpless lugs were taken of the Linkage arm of the new throttle body, leaving just those associated with the return spring. 
Also revised the supercahrger top mount ( as mentioned previously ) to clear the supercharger discharge 
And a little bit of vanity, used "crackle" paint of the rocker cover and polised the letters - personally I like the result. 
Cannot get an Air to Air intercooler that is practical to mount, so have changed tack to an Air to Water unit. I'm using a BOSCH electric water pump to circulate coolant and will use an Aircon condensor to get rid of the heat. A little more costly up front, but saves the big expense of a bonnet vent if a top mounted Air to Air intercooler is fitted and the almost impossible job of front mounting an Air to Air intercooler.
Supercharger Inlet and Throttle Body Having decided in the interest of simplicity to run the supercharger all the time an intake and throttle is required. The intake on the supercharger is not really a convienient size for a throttle body and the small stub manifold that was fitted was not a usefull place to start...   The standard throttle body was eliminated because: - Its too long
- Its too small
- The start compensator system uses engine water and the hoses would complicate the engine bay
- The start compensator doesn't work all that well anyway.
- Hard to arrange "Fast Idle" when the winch is runnning.
A larger throttle body was selected ( capable of passing small children and lawnmowers ) which also has a stepper motor Idle speed control system ( electronics are yet to be started however ). Even though it is oversized its easier to fit as a Couple of the supercharger inlet studs actually are the right spacing for the throttle body…. A small stub manifold is required to adapt the supercharger to the throttle body. <</images/stories/ross/Tbody-Blower.jpg>> <</images/stories/ross/BlowerInletManifold.jpg>> There's a significant amout of machining to be done on the stub manifold as its internal section has to go from round to rectangular. Quite rapidly, and I expect to have to do a lot of blending with the die grinder internally and a lot more milling externally to get it to look ok. The air intake to the throttle body will be a 90 degree unit. Also have to look at extending the throttle cable and changing the throttle shaft cable horn.
A tip for HD series rebuilders… If you look in the engine section of the manual you will see a matrix of sizes for main and conrod bearings. You pick up a series of numbers off the block and conrod then measure the journals - plug these into the matrix and then get a number and color so you can talk to your Daihatsu spare parts dealer and end up with a substantial bill. There is another way. When you look into the aftermarket bearing situation - there will be a profound silence when you start quoting Daihatsu bearing codes and colors. What you need are sizes. ( MM or Inches ) In the case of the main bearings, measure the main bearing journals on the crankshaft AND the main bearing tunnel in the block. The conrod big ends are similar - measure the big end journal on the crank then the inside of the conrod. Take these sizes to you aftermarket supplier and suddenly they understand what you are talking about, and as great side effect you save about 70% ! My local bearing manufacturer ( ACL ) also had a wider range of oversize bearings available than Daihatsu and so even damaged cranks could be reground and reused. You will need a micrometer that reads up to 50mm and expanding gauges to do the inside measurement ( or an inside mic ) - however most digital verniers nowdays are quite good and if used carefully will also tell you what you need to know. ACL also has thrust bearings available - so do the lot if your going to rebuild.
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