khnitz

Over the course of the rest of this year, I will be gathering advice, parts, and courage, in preparation for swapping the -DE drivetrain from my 2005 350Z Enthusiast 6spd, but with worsening rust and now expanding clearcoat delamination:

A pic from the Summer of 2022.

...to this recently acquired, originally-from-TX, 2003 -DE Enthusiast:




The motor blew on the '03 at 120k miles. The body is very clean and solid, and the VIN check did not reveal any accidents. I have enough projects on my plate right now, but there will be time to make this a runner using my '05's engine (at least) next Winter.

My 2005 has about 162k miles, but the motor is tight (knock-on-wood) and the drivetrain has been running great. There are no weird noises from the transmission or differential, and the clutch is grabbing fine with no slipping.

So, the minimum work would be to move the motor+trans from the '05 to the '03. That should get me a running, rust-free Z.

But, based on what I've learned here on my time in the forum about the first-year 350Z's, there are some things that would make sense to fix, and maybe some improvements to incorporate:

• Swap my known-working '05 engine and transmission in one piece over to the '03. I've thought about whether I should replace the clutch or the rear main seal and transmission input shaft seals while I have it out to move over, but I'm also of the "if it ain't broke, don't fix it" mindset on this one.
• Move over whatever is needed to use my '05's keys and fobs on the '03. Driver door lock, ignition lock, behind-seat storage cubby and what else? BCM, ECM, Cluster? I have more keys and fobs for my '05 than the 1 key+fob that came with the '03.
• Although both my '05 and this '03 have the carbon cloth seats, the '03 shows side airbags, where my '05 doesn't show that on the seat. Were side airbags an optional thing?
• Of course, the stereo from my '05 is coming over to the '03. I'll have a lot of work to do there, especially with applying the sound dampening mat again.
• The "feathering" issue. Given that this '03 had 120k miles before the motor blew, I'm hopeful it either didn't have the issues or they were resolved at some point. If not, what should I look to move over from the '05 to minimize the chance of having feathering problems.
• There's the fuel-filler recall to check on - if it was done to the '03. If not, I'll look into doing it.
• I've thought about going to the less-complicated single belt-tensioner setup, too.
• I'll likely move the seat belt extenders over to the '03 from the '05, as well as the center console kneepads.
• Move the Nismo shocks I have on my '05 over to the '03. Or, I might just move to Bilstein shocks. I like the stock ride height, especially given the state of our roads in MI, and that's why I'm also not planning on a wheel up-size/upgrade. The stock 17" rims and ride height give enough forgiveness for mistakes with our potholes, so I want to preserve that.
• The under-body braces on the '03 are still pristine, so I don't know that I'll move the Ultra Racing braces I put on the '05 over to the '03 right away. I may just hang onto them as spares.

When it comes to any performance enhancements - it is a DE, so I know it has its limitations. And, I'm not looking to add forced induction. Still, if the engine is out of the car(s) for the swap, maybe there are some things I should look at. I really don't mind the stock exhaust, so I'm not looking to make an upgrade from the exhaust manifolds back. But would headers, the intake plenum spacer, and a larger throttle body be reasonable mods - capping it all off with a tune? Or is none of that worth it unless I am also changing the rest of the exhaust?

Any other ideas, tips, suggestions?

TIA !

dkmura

iTrader: (64)

Before you get started, one question to ask is how did the engine in the '03 Z blow? If you're not sure, it could lead to problems down-the-line. Depending on where the damage started from, there could be shrapnel left in oil lines, junctures and parts that might be reused. I've seen too many engines compromised by such damage such swaps, so beware of falling into this trap.

khnitz

That's a fair question. All I know so far is that when the seller (a young man who bought the car last summer) started driving it after his purchase, it was using/burning a quart of oil between fill-ups. And about 2 months into his ownership the engine blew. I have one of the con-rod endcaps that he found

I'll be keeping the '05 engine intact as I transfer it to the '03. The oil cooler is part of the oil filter mount and just passes coolant through it, so there shouldn't be anywhere else where contaminated oil would have gotten.

But, now that I think of it, if there was any compromise between the cooling jacket and the oil passages, metal bits could have transferred into the cooling system. I'll make it a point to tear down the blown motor before installing the '05 motor in the '03! It will be fun to see it all apart, anyway

I feel bad for the previous owner...it looks like he might have paid upwards of $10k for this thing last year. And then to have the motor grenade 2 months later - ouch.

icer5160

iTrader: (4)

Hey khnitz,

I wouldn't worry about trying to keep your 05 keys. The Fobs can be easily re-programmed to the 03, but the ignition key is a different story. It's honestly more trouble than it's worth.

I also wouldn't worry about the rear main seal unless it shows signs of leaking. It's a fairly big job since I believe you need to remove the upper oil pan to do it right. Best done with the engine out of the car, but it can be done in the car, just more difficult. This job requires close attention to detail, one miss-step and you will have leaks around the pan seals.

I assume your 05 is a non-Revup, if it is, then everything should be plug and play. If the 03 has side airbags in the seats, I would just leave those be. If you remove them, you will get an SRS light on. You might be able to delete them, but this would require swapping the SRS module from your 05 or installing a resistor kit to keep that SRS light off. It might play nice and it might not. I believe the side airbags were only offered on the higher level trim packages. Base models, enthusiasts and track models didn't have them, but Touring or Grand Touring did (not sure about the Nismo). I've honestly never looked very deep into the seat airbags and the various trim levels.

When doing the swap, I would pay attention to the clutch and brake hydraulics. If yours (Master or Slave cylinders) were refreshed in the past few years, then I would swap these over.

I think sometime in 2004 or 2005 Nissan upgraded the front sway bar to a thicker/stiffer unit. I think the upgraded sway bars were marked with blue paint, I would swap over the sway bar + mounting brackets and bushings from your 05 if it's the upgraded unit and in good shape.

Definitely handle the pulley delete if you haven't already. All you need is a spacer and a new sized accessory belt for Alternator and PS Pump. Refer to a 2006.5 350Z parts diagram to get the OEM P/Ns. There's also a forum post on here that details what you need. It's a super simple enhancement.

If you recently replaced/refreshed your radiator and hoses, I would transfer those into the 03.

As far as other things to tackle, I would get the Diff bushings done on the 03. If you took care of yours already with something like Whiteline, then your sort of halfway there already. Removing the old bushings is always a pain.

I also highly recommend the GKtech trans mount stiffener kit. Super cheap, super easy. You will have the trans out anyway. If the OEM mount is looking rough, replace it.

Also do a close inspection of all the front control arm and rod bushings!

That's about all I can think of for now. Swapping engines sounds like a serious amount of work, but it's really not that bad. These cars aren't all that tough to work on, they seem intimidating at 1st, especially if you've never done it before. But once you get in there and start wrenching, it's actually not bad.
Good Luck!
-Icer

khnitz

Hi Icer,

Thanks for all the good suggestions!

I wouldn't worry about trying to keep your 05 keys. The Fobs can be easily re-programmed to the 03, but the ignition key is a different story. It's honestly more trouble than it's worth.
Is that because of all the modules that would have to be swapped, or is it because of removing the ignition lock cylinder itself?

I also wouldn't worry about the rear main seal unless it shows signs of leaking. It's a fairly big job since I believe you need to remove the upper oil pan to do it right. Best done with the engine out of the car, but it can be done in the car, just more difficult. This job requires close attention to detail, one miss-step and you will have leaks around the pan seals.
Yeah, it's not leaking so I can live with leaving it alone.

I assume your 05 is a non-Revup, if it is, then everything should be plug and play. If the 03 has side airbags in the seats, I would just leave those be. If you remove them, you will get an SRS light on.
My '05 is a non Rev-up, so it should be a straight swap. I was surprised to see the seat airbags - it was one of the first differences to my '05 that I picked up on. I plan to leave them, as the seat covers (especially the driver's seat) are in better shape than the ones in my '05.

When doing the swap, I would pay attention to the clutch and brake hydraulics. If yours (Master or Slave cylinders) were refreshed in the past few years, then I would swap these over.
A VERY good point. I completely forgot about the new clutch lines and slave cylinder I put in 3 or so years ago. I will move those over.

I would swap over the sway bar + mounting brackets and bushings from your 05 if it's the upgraded unit and in good shape.
ANOTHER good point. I can swap my '05 swaybar over.

Definitely handle the pulley delete if you haven't already.
Will do.

If you recently replaced/refreshed your radiator and hoses, I would transfer those into the 03.
I hadn't changed the radiator or the hoses. Maybe it's time, anyway. Any recommendations on an upgraded radiator? Mishimoto or?

As far as other things to tackle, I would get the Diff bushings done on the 03.
I had not done the diff bushings on the '05, I could tackle it on the '03 while getting it ready.

I also highly recommend the GKtech trans mount stiffener kit.
Duly noted.

Also do a close inspection of all the front control arm and rod bushings!
Yeah, I did these on my '05. Might as well make sure it is all fresh on the '03.

Swapping engines sounds like a serious amount of work, but it's really not that bad. <snip> Good Luck!
Thanks! I had to do 2 engine swaps on my son's 2012 Equinox a couple of years back. The 2nd time was easier than the first

Thanks, again, for the tips!

Karl

Aeneas137

JMHO, I would not do it. rebuild the 03 engine instead. it is not worth all of the trouble to put in a tired engine as a replacement.

khnitz

I appreciate the feedback. Another option would be to rebuild the '05 engine - it would probably be a better starting point. For the '03 engine, I will need to source a complete lower end, as it threw a rod through the side of the block.

I have a longer history with the '05 engine (I know how the original owner drove it, and I've put the last 6yrs and almost 40k miles on it). It's not using any oil and it hasn't lost a step in the time I've had it. Still, I can perform a compression check on all cylinders before I pull it to help determine whether to overhaul it. There are a number of owners here with 200k+ miles on their original DE engines, though, so that gives me hope

Where I'm losing the battle with the '05 is the rust. It's not terrible right now, but it is in spots that are tricky ($$) to fix correctly, and it is only a matter of time before it really starts taking over.

icer5160

iTrader: (4)

For both of these reasons. Messing with the ignition system often leads to activating the security system (Immobilizer or NATS). Since the years and trim levels are different, swapping modules can get dicey if you want to keep things working right. You might be able to re-program the BCM to accept the keys from your 05, but I think the better/safer bet is to get new OEM blanks, have them cut, and then register them with the existing BCM/Ignition system. You don't need to use the dealership for this process, you can go with a skilled locksmith. May I ask why you want to keep your original 05 keys? They all look the same AFAIK.

All that being said, I'm not an expert with the security system on these cars. But since many of the modules communicate over the CANBUS, it's possible that additional steps are required when swapping major modules like the BCM. In many European models for example, you need to go through a re-learn/registration procedure with a dealer level scan tool for a swapped module to work after replacement. Some modules are encoded with the vehicle's VIN. I have a scan tool that should be able to register/pair a newly cut key, and might even be able to register swapped modules, but I have yet to use these features. The most advanced features I have used so far was calibrating an air-ride suspension on a 2013 Mercedes GL350 and most recently, I replaced a failed electronic brake booster & pump assembly on a 2010 Toyota Prius (No way to do that job right without a bi-directional scanner to bleed and calibrate the entire brake system, saved the owner $1500 in labor!).

I really like my 48mm Koyorad (P/N: HH021568). It fits good (tight, but no alignment problems, factory fan package bolts right up!), but I did need to make relief cuts in the core support with a dremel. This was needed to clear the lower support brackets for the AC condenser (or you can grind down the brackets). CZP has it on sale right now for $399. I picked mine up from a company I've never heard of or used before. But they shipped the legit product at the best price. (importimageracing.com). They have it listed for $333.

Aside from that, I recommend replacing the coolant bleeder valve with a billet unit, replace that factory plastic stuff while you have the coolant drained.

If I think of anything else, I'll update the thread.
Cheers!
-Icer

khnitz

Thanks for the additional insight and tips, Icer!

I use FORscan for our Ford Flex, VCDS for my VW, and VIDA/DICE for my Volvo diagnostics. I've been thinking about getting the NDS datascan app for the Z. But you raise good points a out the trim level differences and possible impact on configuration codings for various modules, as well as whether some also store the VIN.

I've spent 20+ years developing Tier1 electronics (ABS, Telematics, Headunits, etc.) so I've had to deal with various CAN and other vehicle busses, as well as configuration management through all that. You make valid points.

Thanks for the tip on the radiator and cooling items!

One other item I forgot to put on the list:

• move the Homelink mirror from the '05 to the '03 so I can keep my garage door programming 😁

terrasmak

iTrader: (8)

Wiring from each car will stay in each car.

you will also keep your original O2 sensors with the vehicle.

khnitz

On the O2 sensors, I will likely move the cats and the 02 sensors from the '05 over to the '03. The reason for this is the excessive oil consumption that the previous owner reported - I fear that the O2 sensors and cats could be contaminated/clogged from all the oil it was burning.

Aeneas137

is your 05 an early or late production model? in other words, is it a DE or a rev up DE? because I think you're going to be transplanting the ECU if it's a rev up. The old tune will not know how to deal with the additional two variable camshafts. you might have already mentioned that but I didn't catch it. Good luck with the swap and please share more photos as you make progress!

khnitz

It is a plain-Jane DE, not a rev-up I will document my progress in this thread, though the majority of the work will not start until next Fall/Winter. I'll go through one last Summer with the '05 as-is

terrasmak

iTrader: (8)

back to what I stated earlier, the O2 sensors stay with the chassis. They are not the same between those years

khnitz

Interesting. They made the 3-wire to 4-wire switch between '03 and '05, then? I'll have to look into that more. But, again, interesting.

So, if that's the case, then I'll be replacing the O2 sensors on the '03 (in case of oil fouling), and moving the non-contaminated cats from the '05 over to the '03.

Thanks for the tip!

khnitz

Checking the matrix at RockAuto, it looks like only the upstream O2 sensors are different between '03 and '05. The '03 upstream is a 5-wire, while the '05 upstream is a 4-wire.

A quick explanation of the differences (1, 2, 3, 4 and 5 wire sensors) is here: https://forums.nasioc.com/forums/sho...57&postcount=5

khnitz

Hmmm...the more I dig into this, the more likely I will be sourcing an engine for the '03, swapping out the best other bits from the '05, and then selling off the '05 as a runner when I'm done. My kids are actually trying to convince me to keep both...but they don't chip in with the vehicle maintenance as much as I would like...AND...my wife probably doesn't want me expanding the vehicle fleet

If my understanding is correct from my research, it looks like my possible vehicle sources for an engine (a non-Revup VQ35DE) are:
2003-2005 350Z - non Rev-Up
2003-2006 G35 - automatic vehicles have non Rev-Up
2001-2004 Pathfinder - would this be only for the bottom end? and then use the heads from the '03Z ?
2001-2004 FX35, QX4 - same as above: would this be only for the bottom end? and then use the heads from the '03Z ?

icer5160

iTrader: (4)

Hey Khnitz,

I think some of the Altimas or Maximas had the VQ35DE. Major differences were the packaging, the block was transverse mounted, so the intake manifold designs are different, maybe also the exhaust manifolds and other odds and ends. Nothing you couldn't rectify with the parts at your disposal already.

Pretty much every 03-06 350Z/G35 with an AT will fit your needs. I think the major caveat will be the O2 sensors, and I think the injectors also changed over the years (maybe this was only for the RevUp equipped Z).
Cheers!
-Icer

khnitz

When I researched, it seems the FWD platform VQ35DE blocks had engine mounts that bolted towards the end of the block, vs in the middle for the RWD platforms. And the bosses for the middle mounting were not on the FWD blocks.

There seems to be a number of potential donor cars around me, even now. I'll keep an eye out and will pick up something suitable before next Winter, for sure.

In the meantime, I picked up a better-fitting cover for the '03.