Ive been looking on ebay for 2.0 crossflow heads to no avail, am i to take it from this then that the 1.6 head and 2.0 have the same size valves and the cumbustion chamber is of the same volume?
Yes, they have the same valve sizes and combustion chamber volumes. The 1.6 options are probably more common here in the UK. Valves sizes are 39.5mm inlet and 33mm exhaust. AFT is a 1.6 engine code that has the non swirl inlet port. AKL is also common 1.6 and has the swirl type inlet port. There are various others but some may have air injection drilling's to the exhaust ports so best avoided, although not too serious an implication.
Right ok. So realisticaly am i right in saying that there would be very little if no gain in a crossflow head compared to a PB head due to the crossflow inlet valves being smaller?
Miles, No that doesn't really ring true as the xflow head appears to flow more in standard form than a standard counterflow head eventhough it has smaller valves.....MrHillclimber has posted some figures in his JMR development thread regarding this You need to bear in mind all the additional components you may need to source unless you are planning on running standard crossflow inlet and throttle body etc.....
there are plenty of xflow engines, 1.6's and the later 2.0 from golfs, boras etc, APK and AQY are two of the codes
Excelent answer that! I'm planning on using the ali inlet for the crossflow (possibly polished) and throttle body. Any ideas if it has the same type of throttle switch as Digifant injection? If it dosnt then what can i use instead?
Got myself a crossflow head now thanks too Mitlom for the tip! Been looking at coolant flanges and the one of them has one sensor hole where as the other dosnt. Trouble is now of course that for digifant you need two sensors, one for the ECU and one for the dash gauge. Where would be a good place to put the dash gauge sensor instad of next to the blue temp sensor?
Miles the coolant flange should have the two sensor holes, both AFT heads I have had have.....it will be that one of them has got a blanking plug in it that is held in exactly the same way as the sensor with the metal spring clip. You just remove the blank and stick your sensor in and job done Tim
Beware as some of the 2.0 ones have some nasty secondary air and EGR rubbish on them....also a lot of the 2.0L ones have a big swirl promoting feature that can cause limitations when taking the head right to it's extreme while porting
Ive now got myself a head and inlet manifold, but no throttle body yet. Just looking at it earlier, there's no where for the ISV to plumb into the inlet manifold. How can i get round this little problem as i dont believe the VR6 OBD1 throttle bodies have a throttle adjustment screw on them.
Quick one about throttle bodies. Does it have to be a VR6 TB that I use? Can i just use any early mk3 throttle body?
Can digifant run without an ISV? I dont really like the idea of drilling a 15mm hole into my nice new inlet manifold so i can plumb the ISV in.
That's where it draws its air from though, there's no where for it to exit from the ISV into the inlet manifold.
oops! Brain fart! on the other hand drilling a suitable hole and then tapping a thread into so you can screw in fitting isnt as daunting as it sounds. I recenlty redrilled and tapped holes in a 2L block so I could get a T4 van engine mount on it. It was weasier than I thought. the inlet will be easier to drill through too, just gotta know the right sizes for the intial hole and the thread for the fitting.
I've got the fitting, thread tap and drill bit for the job its just a case of working out a suitabel place where a) it won't foul the bonnet and b) it looks half tidy.