300zx Manual Trans Swap and Engine Build

[MrFeesLaw]

Hey guys,

Just got my Z a little over a week ago and I'm super excited! I've been trying to get a Z32 for almost 7 years, but the money and the opportunity just never seemed to line up until now. I have a 1993 300zx 2+2 N/A T-Top model. It is currently automatic. I got a great deal on the car, because the automatic transmission was leaking anytime you put it in gear, in an extreme amount. The guy didn't have the time, or the money, to work on it himself so he gave me a hell of a deal. My original plan was to pull the auto and fix it (hoping it was a bad seal), but it looks like the torque converter and several other internal pieces of the trans are pretty badly damaged. I always planned to do the manual swap, but was hoping to save up some money first, but it looks like I'm out of time lol.

Anyways, just ordered over $1,000 in parts, including a used 5 speed N/A trans, new flywheel, performance LuK Gold Series Clutch, new master and slave cylinders and other various parts. Also upgrading to lightweight driveshaft, new rims and tires, full exhaust system, and eventually planning an engine swap to either an rb series or a gm ls platform. Looking to make 600-800 horsepower down the road. Making sure to build the transmission to hold it with J-spec Syncros and other internals.

Will post pictures soon of all parts and some of the labor in progress.

[DCaff300ZX]

Good Luck, build threads are FUN...

[MrFeesLaw]

Finally got some pics uploaded! Going to replace the disgusting tail lights the previous owner worked so hard to cram onto the car. Getting a new front driver (Left Side) fender to replace the beat up one. Getting some aftermarket headlights and making my own custom L.E.D. Blinkers and tail lights. Also going to be replacing the rims and several other parts on the car to my own personal preference.

Will upload pics in a minute of the transmission parts and accessories I have received this week. The transmissions itself I will post pictures of, but I do not yet have. Also have some pics on here of the current Auto trans that I will be pulling next week (you can see how much fluid is coming out, even from the still pictures). Will post pics of the old trans after I tear it apart and will let you guys know what I find to be wrong with it. Everything I remove will be up for sale after the build if anyone sees a take-off part they need.

[MrFeesLaw]

Here are the pics of the parts I have so far. Got a stock Master and Slave Cylinder. Have a stock replacement weight Flywheel, and a Luk Pro Series Gold Clutch. Was honestly a little disappointed that it wasn't gold lol. But like my build assistant said, "It won't matter what color it is once you put it in the car". I just think it would have added to the "build-up" of the build lol.

Also posted some pics at the bottom of the transmission that is currently in transit to me. This will be the manual that I will be putting in the car and I can't wait for it to get here! Super excited to get started on this build! Will post more pics soon!

[JayNoel]

Good luck with the build. I think there's a thread on here somewhere about the wiring from auto to manual Ill look for it this weekend

[MrFeesLaw]

^^^Thanks Jay! That'd be sweet. Still working on getting all my parts ordered, but everything should be here within the week. Super excited! Every day when I check the mail it's like Christmas!

[NolimitZ32]

GL on the build man.

[MrFeesLaw]

^^^Thanks. Ran into a couple complications with my working space in the shop so It'll push back the auto trans removal about a week, but I should be able to start about a week from today. Will post pics ASAP.

[MrFeesLaw]

The guy I bought the car from said that he had some runability issues with it before selling it to me. Said that he thought it needed spark plugs and an oil change cuz it ran pretty rough. Said the idle was horrible, but it got a little better under heavy acceleration. Looked at the stack of parts next to the car and I knew instantly what was wrong.

The guy had removed the exhaust from the car in order to remove the trans, but then realized it was much too big of a job for him to do on his own. So I was checking the exhaust out and found the problem. I asked him if the runability issue went away after removing the exhaust, and he said he didn't know. I told him I bet I could start it up where it sat and it'd run perfect. The car had the downpipes and all rearward exhaust removed, but the headers were still installed.

I got in the car, and started it up. It was loud! But ran perfect. Revved it up a little (2k rpms or so), and it ran really smooth (still loud as F***). Shut it off and bought the car. To this day he still couldn't figure out the problem. If you have even the slightest inclination for cars you will see it instantly if you look at the picture.



The downpipe from the right-hand side of the car (on the bottom of the picture) had been bent so badly previously that it had almost no air flow. To a car, no air flow out, means no vacuum. No vacuum, means no air flow in. No air flow in, means no firing on that cylinder (or weak firing at the least). My poor car was running on 3 cylinders solidly and was making a half-a** effort to stay alive on the other 3.

Just to be on the safe side I am going to do all new plugs and fluids. Will post pics of the new exhaust when it arrives.

[MrFeesLaw]

Sorry for the delays guys. Project got pushed back a few weeks when my daily driver started having transmission issues. Finally got to tear into the z yesterday. Had the trans out in 45 mins at my shop. Will post pics later today.

[MrFeesLaw]

Got the old trans out and got ready to put the new one in over the past few days. Had to stop and find some bolts for the flywheel and clutch, but have them now and everything is going smooth again. Drilled and surfaced the holes for the master cylinder yesterday (still need to do bench bleed so didn't bolt it down yet). Bolted up the flywheel and the clutch today.

The throwout (clutch release) bearing that was sent in my clutch kit came as just a bearing, and didn't come with the center support (the part that actually slides over the input shaft of the transmission). Called the clutch company today and am hoping to hear back from them tomorrow. Most clutch kits come with the bearing already assembled to a new bearing center support, but I may have to use a press to get the old bearing off of the old center support, and press my new bearing on. The new bearing is also noticeably larger than the factory one. I assume this is due to my clutch being above factory spec, possibly causing it to need a larger diameter release bearing. Not sure though...

Will be doing the wiring for the reverse lights, clutch pedal switches, and ignition lockout tomorrow, as well as installing the Manual trans. The shifter and driveshaft are ordered and should be here within the week. Super excited to get her street worthy!

I have run into 2 problems though...

Problem #1... It snowed today...

Problem #2. The car has summer tires...

FML.

[javadave]

Once question before you throw that trans in there, did you change the pilot bushing ? They're different for the auto and manual.

[MrFeesLaw]

What is the difference between them? Already bolted the flywheel and trans up and everything went in fine. Haven't installed the clutch pedal or shifter yet, so I haven't attempted to move the car yet.

[NolimitZ32]

One has a larger ID than the other, I am guessing the Auto is larger since you were able to bolt it up. The pilot bushing can be removed with the clutch and fw attached, you'll obviously have to drop the trans again.

[MrFeesLaw]

One has a larger ID than the other, I am guessing the Auto is larger since you were able to bolt it up. The pilot bushing can be removed with the clutch and fw attached, you'll obviously have to drop the trans again.

So what will happen if I don't change it? The input shaft should line up with the crank still shouldn't it?

[itsa300zx]

You need that manual bushing, it keeps the input shaft aligned under heavy load. Without, it may flex and cause additional bending load to the shaft. I would imagine that it will cause more vibrations too. They are a wear and tear item, best to get one installed. The auto pilot bushing is steel and manual is bronze.

This would be a good time to install the SS flex clutch line:)

[nissanfreak12]

^^^This

Plus bearing damage in the trans, catastrophic clutch damage and/or trans damage. The differences are minimal, but its enuh the flex the input shaft to create a horrific vibration, which in turn could snap/bend the input shaft. Think of it as the carrier bearing on the driveshaft, when the rubber breaks, the vibration is pretty bad. If you wait too long the driveshaft eventually weakens and snaps under pressure. The input shaft is the beginning of the transfer of torque to the driveline/wheels.

Just change it. You wont like the outcome with all the work you are putting in it.

[javadave]

You need that manual bushing, it keeps the input shaft aligned under heavy load. Without, it may flex and cause additional bending load to the shaft. I would imagine that it will cause more vibrations too. They are a wear and tear item, best to get one installed. The auto pilot bushing is steel and manual is bronze.

This would be a good time to install the SS flex clutch line:)

Z1 Motorsports also sells a Nismo version with needle bearings in them, which is the route I think I'll be going when I do my swap.
You can plainly see the differences here Z1 Pilot Bushings

[itsa300zx]

I've heard horror stories of those needle bearing failing and making horrible noises. I had tbe same idea too and bouht one, until i did some research on their failure rate. I just went to the stock bronze one. I believe the needle bearings are for race applications for that extra 0.01% extra horse power and the clutches are replaced frequently . Just stick with the bronze bushing , less moving parts to fail. JMHO.

If you really, really want the needle bearing, i have one for sale for cheap.

[NolimitZ32]

Whats said above is correct, it keeps the trans guts aligned with the rotating assy. and works to reduce driveline flex which can result in catastrophic trans damage. I run the standard Nissan bushing (not Nismo) and have no issues.

[MrFeesLaw]

^^^Thanks guys!

I will go ahead and replace the bushing. I am just very upset about it. I only had a limited time in my shop to have my car done. Now I am not able to get the car back on a hoist for a while. Possibly weeks. So this tiny little bearing has set me back several weeks

[NolimitZ32]

I have always done all my work in the garage, it is a PITA but very doable wth some jackstands and a floorjack.

[javadave]

So here's something that's been bothering me. If you look at the 4th picture in this thread TTNet Auto to Manual Swap, you can see how the auto's pilot bushing sticks out from the crankshaft, but in none of your pics do I see this. Is it possible that a PO dropped a motor from a manual trans car into this car without changing the bushing ?

[MrFeesLaw]

^^^^^^ I HAD THE SAME THOUGHT WHEN WE PULLED IT!!! Me and a buddy of mine argued for about an hour over whether we needed to change the bearing or not! We compared the 2 together and they seemed to be exactly the same! We even had the master tech in my shop over and he said that they were so similar it probably wouldnt make a difference! The VIN on the car is for an auto car so I had the same thought that someone may have swapped a manual engine into the car already! I am going to get in touch with the previous owner and see what I can find out... Maybe I'll get lucky and it'll have lower miles than the car!... Then again, maybe I won't and it's trash lol. I will update you guys soon.

[MrFeesLaw]

I hopped around for a bit on some random nissan sites and it seems a lot of other people are leaving the Auto bushing in, or not having a bushing at all and not having any trouble!... Could this just be dumb luck? Or perhaps does the nissan design not cause any significant change with or without the bushing?... A few people on different sites said that the only reason they put the Manual bushing in was to make clutch alignment easier... As far as I can tell, the bushing that was in the car was a manual bushing... I think I might just go ahead and leave it. Saw several people who claimed to have over 30k miles on their manual swaps with an Auto bushing or No bushing at all!... I still have some work to do under the car this weekend, and it sounds like I will be able to bring it into my shop on saturday for a few hours, so i may just slide the transmission back a hair and take a peek. I thought I remembered the bushing looking the same... But maybe I was wrong.

If anyone knows a way to tell if my car has the original engine in it (i.e. some kind of tag or identification number on the engine that I can match up with the VIN on the car) I would love to check! Also might not be a bad Idea for me to make sure the trans I pulled out was also from that car... There were a few modified wires on the trans, so I'm wondering if the whole car used to be a manual and someone put an auto trans in and left the manual bushing. That would explain all the modified wires on the trans harness... But I could swear when I looked at the title is said Auto!!!... Maybe the previous owner told the state about the swap and they changed it over???... not sure... Any info on how to check this for a Z32 would be great!

[MrFeesLaw]

My custom driveshaft is being made today!!! Can't wait!!! Will be installing driveshaft, clutch pedal, shifter support and short shifter tomorrow!!! As well as bleeding and adjusting the clutch system and routing and welding my custom exhaust system. My headers are aftermarket, and I have Magnaflow mufflers that came off of the old system, but there's lots of rusty clamps and terrible welds and cheap pipe. Literally looks like PVC pipe made out of tin lol. So going to bend and weld 2 and a half inch pipe from the headers back on each side and weld the mufflers and hangers on.

I want to do an X-shaped crossover pipe, but I'm not sure the exact position to put it. I've heard that if you take a crayon and mark a thick line down each pipe, then take the car for a short drive, by the time you get back part of the crayon will be melted. The melted part is where you cut the exhaust and start the crossover. The crayon melts the most in this location because it is where the exhaust gases create the most heat and pressure (therefore being the place you want the gases to crossover to cancel each-other out!).

If anyone has any tips or tricks for the clutch line routing or the exhaust system setup let me know!... Also, how are your guys' exhaust setup? Do they run over the axles and the differential? Or under it? Looks like there is enough room to go over, but I don't want to end up having the diff come up and hit the exhaust if I hit a big bump, or if I decide to get lowering springs or coil-overs.