Fitting the XF TB to the plenum body edit: sorry guys, the pictures were hosted on my isp that went bust a while ago. I no longer have these pictures, but the guys are R31 skyline club put a copy of my how to on there site and hosted the pictures there. If you like to have a look http://wiki.r31skylineclub.com/index..._Throttle_body (http://wiki.r31skylineclub.com/index.php?title=XF_Throttle_body) One thing i have changed over the time i have had it on my car is the pipe that comes from the throttle body to the idle air control valve and has another little pipe coming off a T-piece going to the rocker cover. I noticed my idle air control valve started getting kinda caked up with oily crap. So instead of having that rocker cover hose tap into that line, make its own pipe that connects it to the intake pipe. I would recommend a spot between the TB and the AFM. I have mine between the air filter and AFM at the moment. but i am slightly worried that my AFM will get bit dirty from the oil vapors going by it. Why do it? Well, XF TB has much bigger hole in it compared to the VL TB don’t it? Surely more air gotta = more power This was done on a manual RB30 NA (in a VK). I would assume doing it to a turbo would be pretty much exactly the same. Apparently there are 2 different types of XF throttle bodys. I have no idea what one I have. It came off a 1979 fuel injected ZK ford fairlane. Ok, now to start off with, take the top part of the plenum off completely from the intake manifold (refer to a Gregory’s manual, or just keep taking stuff off until you get it) Take off the old VL TB. Get XF TB and modify the holes so they are closer to the center. You can do this using a dermal sort of tool, or a rat’s tail file. Flatten edges of the TB to get bit more room for head of the TB screws using a small flat file Grind the heads of the TB screws so they are smaller diameter. Bolt XF TB onto the plenum and make sure all the bolts that hold the TB on can screw ALL THE WAY in. TAPPERING THE PLENUM Now you need to match the plenum to the TB. The BEST way to do this would be to weld up the valley around the TB flange on the plenum so you can have a straight hole going into the plenum If you don’t want to do that, you will need to taper the TB hole in the plenum to try and match the XF TB. This is what I did. Ok, now with your XF TB bolted on, open the butterfly and using a fine point marking pen of some type, draw a circle of the area that needs to be tapered to. Take off the XF TB, and you will see what needs to be done. Get out the good old dermal and start having fun. Make sure you make the line disappear to make a perfect match to the TB. Rember, a little bit to big is less restrictive then a little bit to small. I used tungsten carbonate bit to take majority of the metal off, then used a stone bit to even it out, then used sandpaper wheel to make it smooth. I found it was easier to just taper it in on a fairly sharp angle first, then from there, work your way around grinding bits off to make the hole bigger, and constantly checking you don’t take to much and go completely thru the edge. When finished, make sure to clean the plenum out perfectly because you don’t want heaps of those little metal bits going into your motor. I used a can of spray degreaser (works better then normal stuff you have to splash around yourself) and cleaned out the inside of the plenum with that, and then good hose out with water. You plenum should like something like this now (not cleaned yet in the photo) Now you will need a gasket. Take the standard VL gasket, and put on how it would normally go on. (put it in so its bolted between the XF TB and the plenum). Now do what you had to do to mark the area on the plenum to be cut, but marking on the gasket this time. Take off the TB and cut off part you don’t need from the gasket You can now assemble the TB back onto the plenum with the gasket in it. Do the TB bolts up tight while it’s all off the motor because it’s a lot easier to do now. THE 2 LITTLE PIPES AT BOTTOM OF XF TB With the pipe that goes to the charcoal canister that originally went to the old VL TB, connect it to the XF TB pipe that has a green ring around it. That pipe goes to a very small hole on the air filter side of the butterfly in the TB. Both the VL and XF TB’s have this little hole. As for the red hole, I could not figure out where it went, and I couldn’t blow any air through it, so as far as I could figure out, it does nothing. But just to be on the save side, block it off. THE WATER LINE With the water lines that use to run through the old TB, you need to make them connect. I did this by removing the old bits of pipe, and putting in a short piece of air hose in between instead. Maybe dodge, but it works. Now you have 2 big holes in your XF TB that you need to do something with. You can either block them off, or use them. In my case, I blocked the one on the top. I removed the pipe bit by grabbing it with pliers, and then turning it and pulling it out at the same time. And with the bottom one, I used it to connect to the top of my rocker cover, and to my idle speed control valve using a copper plumbing bit as shown below. Please note that in this picture, I have both the pipes removed. I ended up putting the bottom one back in later. The pipes will be where the arrows are pointing to. You can see on the inside of the TB where the holes are. This is what I ended up using to connect my pipes together. I recommend getting one that is 3/4" all the way with a 1/2" tap off it that goes to the rocker cover. For the second top pipe. I blocked it off. The size of the hole is very close to 15mm. So I went searching for a 15mm welch plug. Such a thing does not appear to exist. So you have some choices here. When the TB is off the motor, drill the hole out to a bigger size, you could leave the pipe bit in there, and try and find a big rubber block bit to put over it, or you could remove the brass pipe bit, and get a 16mm plastic thing that you nail onto the bottom of tables and chairs do they don’t scratch the floor, and wack that in. (yep, sounds dodge eh?) I have no recommended ways on how to do this. You will need to work out your own way. THE THROTTLE CABLE Now to get the throttle cable to work properly, you need to shorten it. However, I got around this by spacing out the bit of metal that holds the throttle cable adjuster bit. (You will require longer bolts for that bracket to do this) I think they were 80mm long M8 threaded bolts that I used. You will need it to be spaced about a extra 40mm away. THE TPS Now to get the TPS working correctly, you need to change 1 of the wires around on the VL plug, and completely remove another one. BUT this will ONLY work for the manual. If you have an automatic, you have some extra plug and I got no idea on how it works because I don’t have one to test. How the TPS on the manual VL TB works, is it has a little switch in it, and when the throttle is closed, this switch is connected. When moved from idle, switch is an open circuit (not connected). On the VL TPS, it is the top 2 pins that do all this. The 3rd pin at the bottom does nothing as far as I can work out. The XF TPS works exactly the same as the VL TPS, however, there is another switch, and when the throttle is almost completely open, this switch will connect the top pin to the centre pin. When completely closed, it will connect the bottom pin with the centre pin. These are the ones we want to use. Now what you have to do is on the VL TPS plug, try and remove the bottom wire from the plug (so it comes out with its little metal bit also). You do not need this wire, so either chop it off, or just tape it up out of the way. Now you need to remove the top wire (with metal bit also) and push that into the bottom part of the plug. Hope that made sense because it’s kinda hard to explain and I didn’t take any pictures of the process. THE PIPING Now you need to do something about your intake piping as the XF TB is much longer then the VL one. Get some nice chrome looking 3” pipe to make good use of your need big new TB. I used the 3 inch piping from a VN / VP commodore. To do this, move the AFM up near the TB, and get a flange bit that connects onto the top half of a VN airbox (because its 3”) and bolt it onto the end of the AFM. Use the top half of a VN airbox also for your airbox, and connect the intake piping on. You will need to cut the plastic pipe shorter so it will fit in. Stuff I got from a VN commodore. Completed I'm sure there be heaps of questions, so ask away Some original photos have not been recovered yet.

i have a semi related question... since you are doing this conversion (RB30 into a vk) why did you not go all out and convert it to RB30ET??

Very nice article dude. Well done.

I think you'll find the reason that you couldn't find a use for the other pin on your TPS is that the auto TPS has a contact for wide open throttle and closed throttle, whereas the manual TPS has just the closed throttle contact.

great thread dude!

Reason i didn't go turbo was because of the cost involved. So far to get my car looking how it is, i've spent over $3k and i've done all the work myself also (except for grinding the cam. lukevl did that). And i still have crappy drum brakes on the back! I've got a 25 spline LSD center to put into a diff when i feel the urge to but. Shes gonna be a open wheeler for a while. If the autos use the 3rd wire for full open throttle, then connect it to the top pin on the XF TPS because thats what the 3rd pin on the XF TPS is. And RB30X, did you have a 2.5" exaust for sale a few months ago in the townsville bulliten for $50?? If it was you, i was the dude that brought it. Some original photos have not been recovered yet.

Seems like a lot of work for what results?

hey man you ended up doing the tech article.. youve cerainly had teh photos! Great work.. god tech article too man, Cheers

Quote: Originally Posted by white_vl_bt1 Seems like a lot of work for what results? does the XF TB seems like a lot of work, or putting the rb30 into a vk? I wanted the power, and fuel econemy of the rb30 (202 kinda lacks them) but i wanted to stick with my vk. I could of easily put the rb30 into my car for about $300. ($300 been the amount i paid for a complete vl with motor and 5spd manual. had small front end damage) But i wanted to rebuild the motor, then i wanted to add some performance stuff, then i wanted to paint it, then i wanted to etc etc etc, and its started to add up heaps. As for results, well i'm waiting for some decent weather so i can paint my doors, bonnet, and boot lid so i'm then able to drive the car around. Then i get to check out the results.

howdy my XF tb doesnt have these 2 little pipes the whole tb looks the same except for them...... Some original photos have not been recovered yet.

So its got no other little pipes on it at all? as far as i could figure out for the red ring pipe, it did SFA. The green ring one goes to a little hole on the airbox side of the butterfly, and thats the one you connect to your charcol canister. Have a look on the inside of the TB and see if u can see that hole or not. If u don't have a pipe that goes to it, i guess you might have to find another way to connect it to the intake.

i'll get a camera soon and show u wat ive got

Anyone know if this can be done with a GENIII TB? My old man replaced his on his VU SS and just has it laying around in his shed. I have a spare inlet manifold, hmmm, time for some tinkering...... Would be keen to know if anyone has done it at all.

hey you forgot the results! did it go harder? would there be any use for one on a turbo engine? anyone knwo of anything that would be different when puttin it on the turbo engines? exellent write up by the way

um maybe that a larger volume of air is forced into ur plenum

I just have to buy the right XF TB now and then i can bolt it up.... but i need more help with the plugs for the auto conversion....anybody done it with auto and care to share....

Quote: Originally Posted by andy_vlct hey you forgot the results! did it go harder? would there be any use for one on a turbo engine? anyone knwo of anything that would be different when puttin it on the turbo engines? exellent write up by the way I can't really say if it went harder or not from standard. I brought a manual VL for $300, and i took the motor out and completely rebuilt it, got cam grinded, port and polished and shaved the head, done XF tb mod. The motor then went into my VK, and had extractors and 2.5" exaust put onto it. The only driving i did of the stock motor was when it was in the VL, and that was only to drive it home. What i can say about the car as it is now is that it doesn't feel like it has all that much power under 3000rpm, but after that, it starts to really kick, and its still pulling quite hard all the way up to the rev limiter. It feels like the limiter needs to be increased. There is some power down low, i can pull a killer burnout most of the way through 1st gear (no brakes). I would like to take it down the track to see what 1/4 mile time i get, but my second gear synchro is r00ted. So i can't change into 2nd at high revs. Totals kills any chance of decent time. (how it was when i got the gearbox in the VL. And yes, i knew about it, but i still put it into my car) When i get some more money later on, i'll fix it up.

got a question wot bout the xf tb that hav the other TPS? how do u hook this 1 up or is it just beta to go get the other tb that has the big black tps? i mite hit the wreckers 2moro n c wot the goin price is

if it's a series 1 t/b and has the little tps on it. you have to remove it and grind a grove in to the rod, so you can fit the vl tps.

So what am i fitting? Are we using the actual XF tps? Or are we pissing hat off and using the Vl tps? thanks