need help with Gears--buying tomorrow, also o2 sensors, and exhaust question

[my$100project]

Ok, I'm going out and Buying 3.73:1 gears and an x-pipe and mufflers tomorrow. Have my mind made up from the sounds list. I just rebuilt the motor--bone stock---and it is missing an o2 sensor. Since I'm going with an "off-road" exhaust (no-cats) do the o2's even get used? Hate to waste my money to find out They don't even thread into the new exhaust.
My next question and even more important is the good ol' gear question. I have noticed that Ford Racing Products sells a gear, so do other companies. The Ford Racing brand even varies in price from $150-$250 depending on where I go. Aren't all Ford brand kits packaged with same parts, and is there any other brand that is of better quality? What Brand do you recommend I use?---The one's who have swapped to an aftermarket gear. Help is greatly appreciated, purchasing is to be done tomorrow, so any posts would be great.
I've been searching and noticed different types of sets and have noticed Ford Racing sells Diff Torsen 8.8 Traclok 8.8, and truetrac 8.8. Anyone know what the heck these are??? Some are 28t and some are 31t. Kind of confused, I'm guessing that by my searches so far that the kits come with get ring and pinion only, which has no effect on Trac-lok or truetrac design and that these are different parts??????????? Please educateededed me with your knowledge.
My wife is cracking up with the smilie laughing so hard it's crying so, I had to add it, twice.

 

[Insane3D]

Well, to answer your O2 question, the car will run without them, but it's a vital sensor for the ECU to adjust fuel/air ratios. It doesn't matter if you have an off road H/X pipe, or a catted one, you still us them, and the new pipe will come with the bungs for them. Also, I wouldn;t just get one to replace the one your missing since they are less effective as they age...the normal mileage you get out of them is 60- 80K. If you put in one new one, and kept the old one, the motor might not adjust your fuel/air mixture as well as it should.

For a 87-93 stang, you need two, and you can get brand new Bosch units for $39 ea at your local Autozone. You might be surprised at the gas mileage improvement when you install them too.

I'll leave the gear questions to others...



<-- For your wife..

 

[cobradvm]

If you are planning on installing the gears yourself (but I am guessing that you aren't - just a hunch!) you are best off with FRPP gears. If you are taking it to a quality shop then just go with what they recommend - Richmond is another good gear manufacturer. If you really want to buy them yourself, (rather than have the installer use theirs) I would still get the FRPP gears - call Max a www.fivestarford.com and tell him Howard from WA recommended you call him! and he can probably get you a set for around $150 shipped. The ring and pinion gears are not dependent on what spline your axles are.
You should also get the trac loc rebuilt. The 28t and 31t refers to the number of splines on the axles. Stock is 28 teeth, after market like Moser are 31 teeth.

Good luck - you will love the 373s

Howard

 

[my$100project]

I'm having a guy at school help me install the gears. He's been around a while and really knows his stuff. I just figured while I was there I should upgrade all the other stuff. I spun out today for sh ts and giggles and one tire spun. No hook up of any kind, complete garbage rear, would like to upgrade, I'll be going with the sn95 brake system in the future, maybe I should just do the ring/pinion now and wait till I find a donor rear for the rest? What's the dif between torsen, tracloc and truetrac besides price any idea?

 

[cobradvm]

Don't know much about Torsen diffs - I think they are more of an off road application - here is some more info http://www.torsen.com/general/general_faq.htm
A TruTrac is another type of limited slip differential - it doesn't use clutches so it doesn't wear out. Here is more info on it http://www.popularhotrodding.com/enginemasters/articles/hardcore/0412em_tratech/

What you have is a trac loc which is a limited slip differential. If you are doing one wheel peels, it means your clutches are worn out, and you need to do a rebuild. Ask Max again for a trac loc rebuild kit, and that will solve your problem for less than $100 - I forget exactly what it cost.

You can buy a new differential such as the TruTrac or whatever, but I probably would save my $$ for other things.

 

[HISSIN50]

TL kit should be about 50 bucks for the kit.

 

[Scorcher2005]

hmmm, this brought up a question in my mind. What if you used gears from an 8.8 with 31 spline axles in a rear end w/ 28 spline axles? Just wondering because i just bought gears on Ebay and they came from an F-150 and the item description says they can be used in any ford 8.8 rear, with either 28 or 31 spline axles.

 

[Insane3D]

The gears don't care if you have 31 or 28 spline axles, just the differential does...

 

[my$100project]

Ok, a few more questions pop to mind. I installed my new o2's yesterday and noticed they where mounted before the cats. How does replacing the exhaust with a catless exhaust effect the o2 if the sensors are mounted before the cats?
Also, I bought the ford racing gears and rebuild kit (includes clutch pack and shims) part # m4700b --- They don't seem to have a "deluxe" rebuild kit for the trac-loc system. The only one I did find was $50 less than a complete assembly. I did however find a kit from oreilly's for $75--the same one as advance sells for $119. It only carries the bearings. Is it not common practice to replace the bearings, but to just clean them up and repack them when redoing the ring/pinion and clutch packs? 89 with 145***

 

[Insane3D]

Ok, a few more questions pop to mind. I installed my new o2's yesterday and noticed they where mounted before the cats. How does replacing the exhaust with a catless exhaust effect the o2 if the sensors are mounted before the cats?

The O2's are not affected by the cats at all. It doesn't matter to the O2's, the ECU, or the engine whether or not you have cats. I'm not sure who told you running a catless exhaust affects the O2's, but it doesn't.

 

[my$100project]

That's good news, I just heard of so many "mil eliminator" and check engine code problems from the catless exhaust and bad o2 readings. Guess it was bad info.

Any idea why the common rear-end rebuild kits from ford racing aren't sold with bearings? I mean if they don't sell the bearings with their "rebuild kits" there must be a reason.- Hell, maybe I'll just buy a set from O'reillys and clean/check the condition of the old ones and decide to reinstall or use the new ones after I have it apart.

 

[89CopCoupe]

The o2 sensors detect oxygen content coming through the exhaust vapors and then sends that signal up to the computer ... the ECU (comp) interprets the signal and determines whether or not to lean or richen the fuel mixture.

With 5.0 EFI, they are essential ... cats are not

 

[HISSIN50]

That's good news, I just heard of so many "mil eliminator" and check engine code problems from the catless exhaust and bad o2 readings. Guess it was bad info.

Seems to me those are for OBD-II cars with O2's before and after the cats.

 

[Insane3D]

That's good news, I just heard of so many "mil eliminator" and check engine code problems from the catless exhaust and bad o2 readings. Guess it was bad info.

Ahhh, that explains it. Our cars, 87-93 Stangs have the OBD-I ECU which is mostly a passive system. The newer cars, '96 and up, have the OBD-II ECU's that are much more of a PITA when modding. On those cars, removing the cats will cause problems without the correct mods to the ECU. This is probably where you heard that info.



Edit:

Hissin beat me to it.

 

[HISSIN50]

I know Insane is talking about V8 powered stangs (more specifically just foxes), but for the sake of SN95 guys who are told otherwise (parts store guys love to mess with them), the 94-95's have both OBD-I and OBD-II diagnostic plugs/ALDL's.
The V6's got OBD-II in 94, whereas the GT's did not get OBD-II till '96 with the mod motor. But all the wiring and plugs are in both.

Insane, if you typed one-liners like me, you would have beat me.

 

[Insane3D]

I know Insane is talking about V8 powered stangs (more specifically just foxes), but for the sake of SN95 guys who are told otherwise (parts store guys love to mess with them), the 94-95's have both OBD-I and OBD-II diagnostic plugs/ALDL's.
The V6's got OBD-II in 94, whereas the GT's did not get OBD-II till '96 with the mod motor. But all the wiring and plugs are in both.

Insane, if you typed one-liners like me, you would have beat me.

Forgot about the hybrid OBD system in the '94-95's. As for my posts, you're right...but it's even worse that my typing sucks so I spend another 10 minutes checking it before I post it...