Thank you for the kind words FieroLost! Unfortunately we arrived there after they closed off the show so we all separated to find parking which was aways from the event. I’ll post the few pictures that I did take during the short time I was there as soon as I can upload them on the laptop.
Wow! It’s been over a year since my last update... This one is very short. Car still runs great and it’s still a blast to drive. I drive it at least once a month to keep things from drying up.
Yearly update! I bought new tires since the old ones were over 12 years old. They were hardly worn with only ~4500 miles on them so I bought the sticky Michelin’s and it helped the ride immensely. I still get an off and on shake around 75-80 mph. Not sure if it’s the wheel balance or some other rotating mass. Otherwise, the car is still driving fantastic.
just blew about 3 hours reading through your entire thread!! then saw that you had just posted another update today!!! im so used to reading old dead threads it was refreshing to see i was on one that is still active. i am hoping to follow in your footsteps with a 4.6 4t80 swap in our 87 notch. im glad to see you ended up with the stock intake, they really are a marvel of engineering. Other than getting your bank to bank afrs balanced out did you notice any increase in low rpm torque with the stocker? love your build and hope to run into you some day.
Thank you jab018! It’s starting to seem like it was a long time ago when I began this journey. I just wanted to find out if I could see the project through and have a somewhat reliable car in the end. Regarding Russ’s ITB intake vs stock. I never got the system running well enough to get a comparison. Putting the stock intake manifold on fixed the map signal issue and it has been running great since. I really need to find a tuner with a dyno and get the fine tuning completed. I sent the ITB intake setup to forum member Will as he showed interest in trying it out. I’m not sure if he’s tinkered with it yet or not.
I wish you luck and success swapping in the 4.6. It sure makes these little cars fun to drive.
Thank you jab018! It’s starting to seem like it was a long time ago when I began this journey. I just wanted to find out if I could see the project through and have a somewhat reliable car in the end. Regarding Russ’s ITB intake vs stock. I never got the system running well enough to get a comparison. Putting the stock intake manifold on fixed the map signal issue and it has been running great since. I really need to find a tuner with a dyno and get the fine tuning completed. I sent the ITB intake setup to forum member Will as he showed interest in trying it out. I’m not sure if he’s tinkered with it yet or not.
I wish you luck and success swapping in the 4.6. It sure makes these little cars fun to drive.
It's on the list, but I have to get my engine running first.
will, i have several cores and at least one donor vehicle. let me know if you need any parts. i am kinda intermittent on the forum here but let me know if you want a contact number. josh
will, i have several cores and at least one donor vehicle. let me know if you need any parts. i am kinda intermittent on the forum here but let me know if you want a contact number. josh
What state are you in?
I appreciate the offer, but I think I'm doing ok.
However, if you have a damaged '85-'88 Fiero engine wiring harness, I'll take that off your hands... I need to tear it apart to build my engine harness.
I’ve mentioned this before but the Fiero has always had a high frequency vibration starting at roughly 75-80 mph. I don’t usually drive those speeds so I never really pursued finding the cause of the vibration. As Californians started moving into AZ the speeds on the freeways and highways have increased. If you are driving 75, you are in the way. So a couple of days ago I tried a few things like getting aluminum hub centric rings and having the wheels balanced again. Neither of those made any difference concerning the vibration at higher speeds. My next thought was the differential carrier bearings being a little worn allowing the tripod joints to cause the vibration. When I went out to put the Fiero on the lift I noticed that some transmission fluid had leaked out onto the floor. First time this car has leaked anything since I started driving it about 13 years ago. I did check for side play at the tripod joints and there is enough to be concerned. The fluid is not leaking from the axle seals though. I’ll probably need to drop the cradle to get a better look at the transmission and likely just install the spare one I have on hand. One question I have though. If I replace the differential carrier bearings, will that remove a lot of the play or not so much? The transmission I have in the car had about 68,000 miles on it when I started driving it. The replacement transmission has about that same mileage on it as well. I have read that the axle bearing stabilizer/seal is not a good idea. Any other suggestions?
[This message has been edited by cptsnoopy (edited 01-14-2025).]
If you replace the differential bearings AND properly set the preload, then the play will be largely removed. This is the right way to address this.
It will also make the transmission last longer.
Differential bearing wear changes the gear mesh between the output pinion and ring gear, increasing the stress and load at that point, and leads to transmission failure breaking the case in high power swaps.
One question I have though. If I replace the differential carrier bearings, will that remove a lot of the play or not so much? The transmission I have in the car had about 68,000 miles on it when I started driving it. The replacement transmission has about that same mileage on it as well. I have read that the axle bearing stabilizer/seal is not a good idea. Any other suggestions?
Correct. The stabilizer bearings are not a good idea. My experience is that they gall the surface of the CV joint on which they ride. This happens because that surface is not intended to be a bearing race and is therefore not very hard.
There are two potential sources of play. The first is the differential bearings and their preload. If this is your problem, then the two inner CV joint cups will rock back and forth as a unit in their lateral play. Put a hand on each CV joint (yes, it's awkward) and feel if they move together. Normal driving will eventually cause this wear, although 60,000 miles is low mileage to see it.
The other possibility is that there is wear in the differential itself in the interfaces between the side gears, the side gear thrust washers, and the diff carrier OR the shanks of the inner CV joints and the diff carrier. This is not normal wear. A history of one-wheel-wonder burnouts will do this to a transmission, though. If the inner CV joints rock back and forth independently in their lateral play, this is your problem.
By "high speed vibration" do you mean a high frequency vibration or a wheel frequency vibration that only becomes apparent at high speeds?
