Another Possible Intake Upgrade Option

[Cuong Nguyen]

I have already fitted the intake setup off a first gen Xterra.

 

Parts used:

rubber intake tubing

air box with attached MAF sensor

 

VG30 wiring to VG33 MAF sensor:

White wire : B terminal

Black wire : C terminal

White/Black: D terminal

 

Reason I am working on this is because I plan on swapping in the VG33E motor that I'm putting together to replaced my tired VG30E. I'm working on it now until my oversized pistons come in from Summit Racing.

 

What are the benefits of using a late model airbox with equipped MAF sensor?

well, the MAF sensor body is a whole lot bigger and less restrictive than earlier models and the airbox is slightly bigger with bigger inlet ports. Also the intake tube in fits over the stock VG30 throttle body. The VG33 is slightly bigger but I'm kind of lazy to figure out how to make it work on the VG33. The difference in size is not substantial enough for me to attempt.

 

ISSUES:

right now the motor runs rough and it I smell a whole lot of unburned fuel. What makes this setup hard to diagnose is that a long time ago, I was having issues with the motor running rough and it was suggested to me that I splice into the "ground" wire of the MAF sensor harness and hook it up to somewhere on the truck's body and the problem went away. Now, I removed that ground wire fix with this new setup and it runs rough like before I did the ground wire fix on the previous setup. So I hook up the ground wire fix and the engine smooths out but the ecu put it back in fail safe mode and I cannot rev past 2600 rpm.

 

I still need to REALLY DIAGNOSE the problem as to why my wiring crapped out prior to the whole ground wire fix in order to diagnose the new setup if it works.

 

I have a whole bunch of pictures here:

http://s2.photobucket.com/albums/y5/cuongnutz/VG33/intake%20upgrade/

Edited April 24, 2010 by Cuong Nguyen

[MY1PATH]

on the contrary, for our purposes (not buiding high rev race cars) the 3.0 intake is better on the 3.3. The runners on the 3.0 are already almost too big and the 3.3's are slightly larger. putting the slightly smaller runners on the 3.3 will improve air charge velocity (pronouced torque) in the lower rpm range and will still breathe plenty well in the higher rpm.

Now that you have (hopefully) decided to keep the 3.3 manifold. there really isn't much point to adding the 3.3 thottle body and maf sice the maf needs to be re-wired anyway. You are planning on running the 3.3 on the 3.0 ecu right?

[Cuong Nguyen]

Are you sure about the difference in size of the runners between the models? It is my understanding that they are the same in length and size. Please correct me if I am wrong. I am running the VG33 with the VG30 ECU. The only thing VG30 on my VG33 build is the upper intake plenum and crank. Fast says that the lower intake plenum on the VG30 and VG33 are the same. Difference in the upper plenum is due to different emissions junk and size of throttle body port. So in other words, the throttle body on the VG33 will not fit on the VG30 upper intake plenum. I have two VG33 intake upper plenums of from an Xterra. One has the EGR setup while the other doesn't.

 

I should correct the terminology I used for the intake setup. I am only referring to using the intake tube, MAF sensor, and airbox from a VG33 motor and not using the uppper and lowering intake plenums as they're essentially the same.

Edited April 24, 2010 by Cuong Nguyen

[Tungsten]

the VG30E intake plenum is beefy and provides chamber filling at low speeds, keep the VG30E intake

[shift220]

I'm not sure about the extent of your modifications but I read that you are using the VG30 ECM to run the 33. Once you start changing the combination on the motor and especially when switching engine sizes without changing ECM's, your tune is going to be way out of wack. Chances are you are going to see less power, mileage and reliability. If the MAF's are different, then so are the tunes within the ECM's.

 

With the lack of tuning available for these computers, I would recommend keeping everything consistent with the ECM's for the best combination.

[beastpath]

I'm not sure about the extent of your modifications but I read that you are using the VG30 ECM to run the 33. Once you start changing the combination on the motor and especially when switching engine sizes without changing ECM's, your tune is going to be way out of wack. Chances are you are going to see less power, mileage and reliability. If the MAF's are different, then so are the tunes within the ECM's.

 

With the lack of tuning available for these computers, I would recommend keeping everything consistent with the ECM's for the best combination.

 

Actually as long as you use the 3.0 intake on the 3.3 block the 3.0 ECU works just fine. Most everyone who has swapped a 3.3 in uses that setup and it works just fine - with increases in mileage and performance.

 

Even those who have overbored to 3.4 use the 3.0 ECU. It should be able to compensate 15% anyway and many people have upgraded their ECUs by sending them to Jim Wolf or JET with great results.

[MY1PATH]

I'm not sure about the extent of your modifications but I read that you are using the VG30 ECM to run the 33. Once you start changing the combination on the motor and especially when switching engine sizes without changing ECM's, your tune is going to be way out of wack. Chances are you are going to see less power, mileage and reliability. If the MAF's are different, then so are the tunes within the ECM's.

 

With the lack of tuning available for these computers, I would recommend keeping everything consistent with the ECM's for the best combination.

 

 

most learing-type ecu like ours are capable of compensating for +/- 10%-15% in displacement.

hell me and a budy were talking about trying to run a vg30i of the z24i ecu since the TB is the same lol. (maybe not as likely)

anyway talk about lack of tuneablity and loss of power thats exactly what you get with the 3.3 ecu. theres too much crap holding it back. I've even heard nissan mechanics say the vg33 is a terrible platform in stock form because of all the crap that went arround it compared to the 3.0.

[maikan]

Why would you say that stock VG33 is a bad platform and is hold by crap around it ??

What is holding it back ?

Edited April 25, 2010 by maikan

[shift220]

Well it doesn't know that the displacement is different but it does see the difference in air coming into the engine by the MAF. The reason why I say it can be off is calibrations on the MAF's. If the MAF on the 33 is much bigger then the 30 then most likely the calibrations will be different between the two. But if the AFR's are good and it's not detonating then nothing to worry about!

[MY1PATH]

Why would you say that stock VG33 is a bad platform and is hold by crap around it ??

What is holding it back ?

 

 

well one example is that there is a sensor inside the carbon canister, and EVERY TIME my buddy gets is 3.3 X in a puddle or in the mud it gives a CEL.

 

The emissions systems are more restrictive which dampens the power even more and it has a habit of running rich and sucking gas every time it thinks the emissions are too high. (unburnt fuel is less harmful than Hydrocarbons, nox emissions and co levels)

 

it runs fine off the 3.0 ecu so why try to make things more compilcated?

[Cuong Nguyen]

The knock sensor is another annoying thing too. If that goes out, its a pain in the ass to replace.

 

Back on topic:

 

VG30 specs for MAF sensor:

Battery supply voltage: 11-14 volts

idle: 1.5-2.0 voltage

 

VG33 specs for MAF sensor:

idle: 1.0-1.7 V

2500 rpm: 1.7-2.3 V

[maikan]

Is it possible to retrofitted the 30 intake in a 33 block ?

 

Will that take care of the faulty knok sensor and or other problems??

[Cuong Nguyen]

Majority of the problems that surrounding the VG33 is all the emissions stuff that came with the OBDII setup. I'm not familiar with the stuff and I am assuming that's all ECU controlled and beyond my knowledge. Retrofitting the intake will not fix this problem or any others.

[shift220]

The knock sensor is another annoying thing too. If that goes out, its a pain in the ass to replace.

 

Back on topic:

 

VG30 specs for MAF sensor:

Battery supply voltage: 11-14 volts

idle: 1.5-2.0 voltage

 

VG33 specs for MAF sensor:

idle: 1.0-1.7 V

2500 rpm: 1.7-2.3 V

Is this idling with the VG30 and the VG33 respectively? Or both MAF's on your same engine?

[Cuong Nguyen]

those are the specs i got from the FSMs respectively. I'm not sure if the ECU controls the voltage of it.

[shift220]

No, the sensor is feed a constant 5v and outputs between 0-5 depending on the airflow going through the sensor. This is why I mention the tunes being off because the at the same voltage, different amounts of air are flowing past the sensors. So the ECM is not getting the correct airflow reading if you use a different MAF with the ECM.