You want to build a good motor you first need to make it bulletproof. Now there are a few problems that the daihatsu 1300, 1500 and 1600 motors have with them. The first is the main one. That is the block. The design of the cylinder sleeves is not very good. You see because there is no cylinder wall bracing whatsoever, under turbo conditions( high boost conditions 20psi and up) you get cylinder distortion. This is when all the load generated by the high boosting causes the sleeves to move around( head gasket problems). This can be remedied in one of two ways. The first is the less cost effective way which is to dowel the block. This is when dowels are inserted in the water jackets around the cylinder sleeves holding them in place. Cheap and affective. The second option is one of great cost I can vouch for that. This is when using the AutoCad thingy on the computer they design a block brace. Now instead of just locating the sleaves in spots like the dowels do the block brace completely surrounds them locating them 100% to the block. To mantain coolant flow up to the head there are special drillings for water to pass.
The next stage in the bottom end is the rods. from factory these are pretty piss weak. Mind you they can handle 15-16psi with a good tune and no detonation. These will set you back between 1400-1500 bux. These must be made of good grade billet steel. For other applications apart from turbocharging you can run alloy or titanium if you want to acheive very high revs. The alloy items have a way short lifespan as they have the ability to strech. Argo are the people to use here. You can't beat Aussie made.
Next will be the pistons. Usualy forged high silicone content. Two top people in Aus machine these. You have to tell them what size dish you need as this will play a major part in your final static comp ratio. Specialised Piston Services(sps) and Australian Performance Engine Parts(apep) both located in melbourne.
What else? good idea to o-ring the block. You definately need to drill out and retap the bolt holes and fit custom arp head studs and nuts due to the fact that with the high boost I have experienced head bolt strech. This is all custom gear, and costs, and also takes time to get. Along with the head studs you can get bolts for the mains. Oversized of course.
Now the block has to be deburred, all the rotatingand reciprocating masses have to be balanced and blueprinted etc. That should give you a bottom end that will be able to handle 30psi with out a problem and realistically put out a power figure of 300 horses at the wheels depending on turbo spec.
As for the rest of the motor there is so much you can do with the head depending on how you want to chase your power, how you want your car to drive and so on. Usaully with a turbo you don't have to go to drastic with the cam. A good set of one piece steel valves machined to suit is a must as you dont want the valve head dropping off. Stronger valve springs also. There is no need to go for double valve springs either.
Head gasket should be metal(copper) no more than 80 thou thick. Make sure you use a good sealant( I use threebond high temp sealant) and not too much either. Stay away from the oil gallery.
The rest of the motor is the ancillaries. You need a good fuel pump anything from a VL Commodore turbo bosch pump and up. After my engines last build I believe that there is still some power hidden in the injector positions. So Grog here is one of those trial and error tips. Eight injectors mate. My next set up will to use four 145cc(standard injectors) in the standard locations. Then on the rear of the manifold the section that faces the firewall on each runner as far away from the head as posible I will weld in an injector boss and fit 4 550cc injectors. Fitted further up the runner it will in theory give you a different type of power. Much better top end. Just one of my theories that I have read in books and will try on the new motor, accompanied with a new turbo. These injectors will be staged and each injector will have its own injector trim table. You see the time and money that I will spend doing this after the end result could tell someone and they will have it a whole lot easier. So feel privileged.
Then apart from little things like modding you distributor to run four coils, running different spring rates in your oil pump, baffling sumps the rest is pretty easy. I hope you and heaps of other people on the board has learnt or picked something up from this. If I missed something that you may want to know like with intercooler plumbing for every 90 degree bend that you have you need a straight section that is 3 times in length to pick up the air speed again. That is one area that Ufo's car has a bit of an edge over mine.
SORRY UFO BUT SOMEONE HAD TO TELL THEM. Don't worry they don't know all the tips. We will keep the rest for ourselves.
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