HOW TO: fitting a vvt sr20 onto a non-vvt cylinder head

[norfy]

thought id do a quick write up/guide as there is a real lack of first hand information out there for doing this.


I have currently been building a replacement engine for my 180sx fitted with a non vvt sr20. i was dontated a s14 vvt sr20 engine with a solidly built and upgraded bottom end and didnt want to use the vvt head as it wouldnt look original in my engine bay. Also my aim was to build this as cheaply as possible.


Requirments
- a mid to good range of mechanical skill
- as much time as possible
- basic tool kit including screwdrivers, sockets, spanners, hammer, chisel, allen keys, drill, etc.

Parts required
- s14 headgasket
- id recommend a new short block gasket set
- m8 steel grub screw
- oil
- oil filter

Minimum costs involved
- head skim (if it needs one)
- block skim (if it needs one)
- cost of parts


The vvt sr20 and the non-vvt sr20 phsyically have many differences and direct fitment of a vvt bottom end onto a non vvt head is not possible. however, with a little work it is possible.




what ive found;

- you can use the bare vvt sr20 bottom end with all its internal workings. remove the ancillaries attached to the sides of the block, some may fit and work fine but i have chosen to use everything from my 180sx instead.
- you will need the non vvt cylinder head and all its workings, this includes manifolds and hoses/piping

the main differences in the vvt bottom end are;
- the oil filter housing is different, the thread for the filter is different so use the 180sx item. also i believe the 180sx item doesnt have water lines running through it
- the oil pick up pipe is better, it has a wider 'mouth'
- the vvt block has a oil line running through it and up into the cylinder head. this will need blocking off.
- ive been told the water pump is better due to a metal impeller but i havent confirmed this as yet
- there is a 1.5" water pipe out the back of the water pump housing that is different to the non-vvt one and it will need swapping over otherwise the head will foul.

to prepare the vvt block for fitting;
- swap over the water pipe as mentioned above. there is a shoulder on the pipe to stop it going too far in the back of the water pump, put a large chisel on this shoulder and tap the pipe out. you will need to remove the one from the non-vvt block and fit it into the vvt block. be gentle, it is quite simple but we dont want to damage the good one.
- fit the non-vvt oil filter housing to the vvt block, its a simple bolt up process.
- block off the vvt oil gallery. you need to locate it, with the head off looking at the face its the first hole on the left right next to the timing chain as shown in the below picture, there is a small 4mm ish brass insert with a 1mm hole in it. you need to remove this insert and block the hole. be very careful no to get any swarf or metal drop down inside the hole, we dont want metal filings in our engine oil at all. i rolled the block on its side and drilled out the insert, it actually pulled out when i was halfway in. now thats removed you need to block the hole, it only runs 20 psi oil pressure so it doesnt have to be an amazing plug, i used a m8 tap to put a thread in there about 10mm deep and a m8 grub screw (or end chopped off a bolt and slotted to act like a screw). plenty of thread lock on the grub screw and screwed it in til it stopped and was below the face level of the block. i cannot stress how important it is to keep everything nice and clean, you dont want swarf anywhere.



so now the block is ready, you can use a vvt head gasket of your choice and fit the non-vvt cylinder head onto our prepared vvt block.

everything else is a simple swap over/bolt up.


you now have a non-vvt head on a vvt block. well done.



note; it is also possible to fit a vvt cylinder head to a non-vvt block for performance gains and there is information online about how to do so