I am going to also put in a 3:73 posi from my old 2:73 what do you think it will do for me? And how much do you think it would cost?
thanks

 

Welcome to TGO. You might provide more info (year, make, engine, trans) in your profile--it makes answering questions easier.

JamesC

 

It is a 305tbi runnin 200hp it will be with a shift kit ina 700r4 if that helps.

 

I think it will increase your engine RPM by 36.3636% at all road speeds.

I think it will cost just under $200 for the gears, about $100 for the "install kit", about $25 for the crush sleeve eliminator, about $150 for the girdle type cover, about $475 for the Eaton posi, about $225 for the Superior axle kit, about $20 for fluid and misc., and about 4-5 hours of your time to pull the rear and swap it all and put the rear back in. Less if you have a lift and a trans jack or something. A little more if you weld up the tubes like they need to be done.

 

Wow so its really not worth it?
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Ya thanks any way.

 

:shrug:

That's for you to decide I guess.... I don't think any of the rest of us can make that decision for you.

There's parts you can leave out; but with that mighty 200 HP 305 TBI, who knows, it might grenade at any second if you don't max it out.

 

I'd say keep the 2.73's and throw a moderate stall torque converter in there. Maybe 2200 RPM. That way you get the torque multiplying features of the converter (which should be faster than an axle change would give) while retaining the cruising and fuel economy of the tall gears.

Easier to change the torque converter too.

 

Ok so if i do the 2200 stall what is it doing to my car? Will the car always run a 2200rpms or will the car not move till it gets to 2200 rpms?
thanks

 

As far as 2.73 vs 3.73, with a 700R4 in there, driving around in O/D with the 3.73's will be like driving around in 3rd gear with the 2.73's.

I've had 2.73, 3.27, 3.45, 3.73.....I liked the 3.45's. They seemed to always be in the right power range. Didn't rev too high on the highway. Had lots of pep in 1st gear. Just a good combo.

The stall will be a lot of fun. Hard to describe exactly. It will take a bit more gas pedal to get the car moving from a stop. And it will rev a bit higher for slow city driving (imagine a slightly slipping clutch feel). But when you put your foot down and go for it, it will shift the RPM higher up into the RPM range and give you the power boost of being in the upper HP range even though the car should be revving lower.

My wife used to have a 2800 stall in an LT1. It definately felt different from stock. But it wasn't bad. A little annoying in rush hour stop and go traffic. But for an everyday driver you could use it....For my GTA, I'd like to go with a 2600 stall (since the car has more torque down low, no point in going with a huge stall). For a 305tbi, I'd go with something around a 2200 RPM.

For what it's worth, my wife's old LT1 dropped 5 tenths in the quarter mile when she had the 2800 stall put in. Gears (2.73 to 3.42 to 3.73) only took a tenth off total.

 

I agree i've looked into anything but my 2.73's i think i'm gonna go 3.42's, a better RPM for cruising. Either way good luck! and gears cost around $200

 

Why does my 2.73 rear end only making one tire mark in a burnout

 

Broken posi? its workin like a limited slip or someone lied to you

 

Everything is stock and the RPO codes said it was limited slip

 

then its a limited slip thats why its one wheel peeling

 

this is good info. not tyring to jack here,
but what would be a good stall for my 84 with fact 3.73 possi. i want some punch, but when it comes to how a torq converter works, well i've never had it explained to me.

who make the best torque converter?? where to get one??
thanks guys.
jay.

 

Well first off your better off making sure you stall it AND get the wheels to stick and not spin. Tire spin= Loose race

And i would say a stall around 3000-3500 rpm is a good stall if you want a hard punch. Am i right guys? If you want a good launch but not to rev the engine as much go with a 2400 stall. As far as brands TCI and B&M make good quality torque converters as far as i know.

 

thanks viper.
i guess i should say that this will never see the 1/4 mileand is not my D/D. it will be all street.so maybe 3000 -3500 is to high for what i use it for. sorry.i should have stated what i use it for.
jay.

 

Posi = limited slip; means the same thing, one's just a trade name vs the other is a generic description

The other kind, with unlimited slip, is usually referred to as an "open".

The RPO codes only tell what a car came with; they aren't updated when somebody tears up a part and replaces it with one that's "guaranteed to fit" from their local junkyard.

If a car is a one-tire-fryer, then either it's not a posi/limited-slip at all, or it is but the clutches that are supposed to limit its slip are worn out.

 

Best brands are Vigilante and Yank. Although Edge has gotten some good praise from people the last while too. Stay away from the cheaper brands. This is one part you want to spend for quality. Vigilante will let you get a free stall upgrade in the future too.

My general rule of thumb will be 2200-2400 for 305's, 2600-2800 for L98, 2800-3200 LT1, and LS1's being 3200+.

Being as you have 3.73's, you will have an easier time from stop to moving. Since the higher stall means you need a bit more RPM to make the car move, your 3.73's will compensate for this since they rev with less pedal than say 3.23's.

 

with that said, how much will it help acceleration from a stop light and also when i hit in a passing type manner. i do have a shift kit in her now,so with all that what will it feel like compared to now? will it be night and day?

hey sofa. whats the average cost of a complete rebuild for 10 bolt 3.73.
thanks
jay.

 

o the diff will deff be night and day. you should notice it cause it will shove you into the seat cause your already at higher rpms. you might not notice any accel though cause your not changing ang gearing or horsepower/torque. you'll take off faster though.

 

i'm sorry Goodlookin rs. i don't mean to jack this.

this might be a stupid ? but will it increase 0-60 times? i realize that it doesn't add torq as so much as it changes were it comes on at. or better yet,that it allows more of what u've got to be put to the ground.

i am assuuming that i should rebuild the tranny before doing something like this, or would it be o.k.? its got 135k on it,and it shifts and runs fine.

 

lol could care less you keep asking your ?'s its helping me out to.

 

Yeah this is good info. I was surprised to hear that a torque converter dropped half a second and 3.73 gears only a tenth. I would have expected the gears to be good for a whole second.

 

thats cool. so since my 3.73's are staying and if u guys upgrade ur gears and the t-converter u will prolly shave about 1.5 sec off 0-60. mine 0-60 will go down as well. but by goin from 2.73 to a 3.42 or even a 3.73 and a sweet t/c u guys will feel like u just added 70 h/p to ur ride. NICE!!!!!!!!!!!!

 

As far as the converter lowering the ET and the gears not, it would be interesting to have done those 2 mods in the opposite order. For example, it might have turned out that the gears lowered the ET by 1.5 and the converter RAISED it by .3. Not likely, of course; but without knowing that, there's not enough data to declare that a gear swap is ineffective. We'll never know. Plus, that was a LT1 car, not a L03 one. And furthermore, there's other things in life (admittedly only a few) that are as important as, if not more important than, ET; which gears and converters affect differently. I've driven some REALLY FAST cars with REALLY LOW ETs that I would not want to depend on to get to work in the morning, for example.

IMO both gears and converters are EXCELLENT mods, both really CRITICAL to getting the max out of any modded motor. Or even a stock one in some cases. But to say that one is the be-all end-all and the other does nothing, well, I've seen (and owned) WAY too many cars to make a blanket statement like that.

 

HUH.
who said that gears is ineffective. did i miss something here? changing gears and t/c together would lower et's more than just doing 1 and not the other.
i think i did miss something b/c i don't see where someone said that changing gears doesn't help.

i like u have owned several cars over the years. 1 imparticular was a 2000 mustang gt (sorry) and i went from the fact 3.27 to a 4.10 gear. let me tell u. it was like i put 80 h/p on that thing. it was fvking quick. it was a 5spd.my 0-60 went down to 4.8 sec.via the G-Tech.

so put a t/c that is sized properly for ur application and a 3.42 or better gear,then look out.
sorry sofa if i got this wrong i appologize.
Jay.

 

This is what happens when you put a 3:73 posi (was 2:73 open) into a 350hp/Turbo350 - Notice how quick it turns at low RPM. Wheels will spin at 1100 RPM
Now I just have to get it to hook LOL


Nebraska

 

You tacked this onto a 8 year old thread?