Thread: lowport gone, highport in - questions

alrighty, so here's the setup now. with pics!

So, provided this air control valve (off the highport)



is the same as the one which is now mounted on the power steering, we're ok. If not, we're hooped.


next, I've taken care of the evap canister/egr canister vaccum gallary I believe by deleting the egr that takes quite a bit away, and also deleting the aiv valve.

is it ok to put the pressure regulator straight to the intake plenum as shown here? that's the same as putting it on a 't' the way it was stock right?



which of the 6 wires off the egr is the one for the 100k resistor?


the reason I decided to do the highport whole engine instead of just the lowport head on the highport block, see if you can tell the difference:


and the highport:


and lastly two more questions. one easy one hard.

easy: when I fill up the transmission, the torque convertor fills as well yes?

hard: since the iacv is different for a b15 auto than any other iacv, i looked at my options. I could: manufacture a plate that converts the old iacv location to fit the new. that being said I have an issue. I've inspected the difference between the two (the iacv i have mounts to the throttle body and allows air past the butterfly valve) and there is an issue. The non automatic b15 (basically EVERY other iacv valve out there) allows much less air into the intake plenum than the automatic one does, even when closed fully. were I to still go ahead with the adaptor plate, would having a bit more air going into the intake effect it THAT much? If so, does anyone have ANY other ideas as to what I can do to rectify this situation? the iacv I have is a 6 wire, and the iacv on most is a 2.

I don't know about the auto IACV, but when I did my VE swap, I actually had to use the VE IACV. The B15 unit was a stepper motor with some type of logic that was basically uncontrollable by the B14 ECU I was using. With B14 intake piping and a VE (or B14, whichever) TB, you have a sort of bypass tube going directly to the intake, so you don't need the "notch" that is present on the B15 TB.

Now, if you are using a B15 ECU, there is just no way to control a 2-wire IACV (trust me, I tried), so you pretty much have to either switch to a B14 or B13 ECU or go with the adaptor plate approach. I have a spare manual B15 TB at home and can take pictures if you want to compare "notch" sizes.

well, I guess my issue is no longer the adaptor plate as such, but the amount of air difference between the iacv's. if there was a way to modify the current iacv to accomodate the difference in air getting through to appease the motor as well as the computer, i'd be all set to put it back in.

My lowport to highpoirt swap was much easier... The IACV was the same on both motors so no issues there, and I deleted all emissions- EGR, evap, BPT, AIV, etc. The FPR will be fine running directly to the manifold, but I don't know anything about autos and torque converters.

yes the torq converter fills up.. i usually take the converter and fill it up manually and then instal everything together..

I guess the first question is: what ECU are you planning on using?

I don't know about how you can accomodate the MT setup to your current TB, but if you need mine, I don't need it anymore, so you can PM me with an offer. I'm willing to let it go for cheap as I'm currently cleaning out the garage of parts I won't need anymore. I can also include the IACV if it is different, but it would come without the TPS.

I'm using the b15 ecu.

Update!

Ok, so everything is working out fine so far.
Here's what you have to do to convert an old obd1 engine to an obd2 car.

1) Highport throttle body
2) Lowport iacv valve (although, if you have an auto tranny like I do, here's the issue you run into!
3) make a block off plate for the iacv. this was my second plan, but hey, whatever. the way it worked out made me realise how crappy it ws to make and how impossible as well to get it to work right. SO that leads me to how to put it in.
4) Take the power steering pump from the lowport and swap it to the highport. Take the vaccum tubes, one on the outside of the engine where the airbox is. the other on the tube that comes off the bottom of the intake manifold.
5) Take the evap service tube. One goes to the selenoid, the other goes to...you guessed it. another section on the intake manifold
6) this is taking forever. I'll put some pictures up to show you what I mean later when I get back into town
7) What's next is you need the air regulator from the highport. then, 't' off of the tube before it goes into the air regulator. Next is where it takes some creativity. Find a peice of steel and drill through it where you'll put two nipples. This will allow you to attach the nipples to the tubes you 't'd off- then 't' off the other tube as well. So you now have your iacv valve attached to do what it's supposed to. one tube goes to the air regulator, one tube goes to the iacv. then they both go into the intake manifold.
6) you have to wire your air regulator in. the way this works is you have to find your fuel pump relay. then splice a wire off the hot wire, put it to the air regulator and the other one gets grounded. This will allow you to have a fully functional sr20 highport engine. What else?
7) take the old b13 or whatever harness you had and get the injector connections for the highport. locate the b15 injector attachments, and replace them with the new ones. The injectors are different though, so you have to splice the ground 'yes the ground!' with a resistor - according to andreas miko:
"Resistor goes on the ground.

All Injs on the Nissan SR20DEs share the same positive and use the ground as the trigger.

It clearly states that all Nissan Side feed injs are High Imperdance. So since they are, I guess you are getting low impedence injs.

6.8 ohms 10 watt can be found at Radio shack works great with MSD injs."

That's all i can come up with so far, i'll get a couple more things up to make more sense.

But all in all IT CAN BE DONE!

shoot, so after reading about the egr delete:

the resistor trick does not work for p11 or b15. anyone else have a trick to do so?