I have already installed an open element and a hooker cat-back, now which is going to make a bigger difference; headers or 3.42's and posi? I currently have the peg leg 2.73's, and the tranny is a 700R4. I want the biggest SOTP difference, and from what I can gather the 3.42's shouldn't kill my mileage. I do a lot of highway driving around 80-85mph so I know I don't want 3.73's. Thanks fellas

 

You will really fell a sotp difference if you put the gear's and posi in. but you really need the headear's too. but i would do the gear's and posi first cause their is no point in having power if you cant get it to the pavement.

 

I think they will give you similar gains, the posi will give you a lot more traction, but I would probably do the headers and 3" cat first since it will give you a nice exhaust sound, actually make more hp and will probably be a little cheaper unless you are putting in the gears yourself. You do need both though.

It's probably going to be more fun having a car with little exhaust note and no traction, than it is still having a quiet car and more traction. I personally did the gears first b/c I couldn't stand the one wheel wonder anymore and nothing is more gay than doing a one-wheel burnout for your friends in HS. But I'm older now and would probably rather had the power first, the gears won't really help you on the highway where HP rules.

 

teh gears will be a better bang for hte buck mnod and will have little to no effect on your gas mileage on the highway.

later
tim

 

i woudl go with headers first because if your engine cant breath you wont have any power to put to the ground. after headers then do gears and posi

 

Hey everyone, about 2 weeks ago I told my dad my car was acting funny and the Service Engine Light came on. So he went to check the codes by using a paper clip and plugging it into the two spots by the fuse panel. well he left the paperclip in without telling me, and I started my car probably about 20 times without knowing it was in. I remember hearing a rumour that doing this fries the computer
Please tell me im not screwed and this was just a rumour I heard

 

Ignore the last post, I put it in the wrong sopt, sorry everyone
If a moderator see's this, Could you please move it for me
Sorry again

 

headers!!!!!!!!!!!!!!!!!!!!!

 

Come on guy's i thought you were all smarter then this. Why would you put header's on a car before you bought gear's. I mean come on. i have power in my car and wish i would have bulit the rearend first. IT's like bulding a house. you have to bulid the foundation before you can bulid a house on it.

 

AMEN, you can't tell people that enough.

notice i have over $1500 into SUSPENSION so my car will hanldle power that i thtought it. and i have a couple of basicly useless bolt ons , and the only reason i have them (other than exaust) is because got them for nothing or basicly nothing.

i am just now getting to adding power, and i am doing gears/posi and or around the exact same time i am all grins just thinkinga bout 3.42s posi and a little more power.

 

I did the headers-back first and currently have the 2.73 posi. I guess if I didn't have the posi, I'd do the gears first - one-wheel takeoffs are pretty lame. But since I do have the posi, exhaust made much more sense - and it sounds perfect!

Gears are around the corner.

 

exhaust is nto worth nearly the et gain of gears and posi. exhaust is worth maybe 20hp at most, if you stock parts are really clogged up an dbeat is may be worth more. that kind of power gain with perfect traction, which you will never get out of the peg leg, is worth about 2 tenths. posi and gears has been shown to be worth at least 3 tenths and soem people have knocked of 5 tenths with 3.73's and good traction.
so the exhaust systems sound great, you can certainly impress a bunch of ricers that dont' know any better. but when it is show time i woudl put a set of 3.73's and a posi on line before any exhaust system.

later
tim

 

i'd say the gears first, hands down.

1) you can do the gears cheaper. slp has take off posi units for 99 dollars. new gears are less than 200, and since there are so many v6 cars around, used 3.42s are even easier to pick up. 50 bucks for the installation kit and 150.00 for labor and you have the whole thing done for less than the cost of the headers without installation!

2) no one will see the flowmaster, etc., under your car, so, there's nothing to tip them off. sleeper!

3) put headers on it, make it sound cool and you'll be doing more (planned or unplanned) burnouts than ever! you'll be wearing that one tire out.

i bought my car with a cat-back exhaust already installed, but no headers. i'm going to have a dyno tune done and take it to the track the way it is to establish baselines, then, the first mod will be 3.42s and a posi!

 

I gained .6 sec and 5 mph with headers, i garauntee you won't gain more than 1 or 2 mph with gears b/c it doesn't add any HP. I have no before times for gears, but I ran 16.0 @ 85 mph before headers and little more than a K&N, 160 stat, bumped timing and headers I ran 14.77 @91 mph with a best of 93 mph. It's all about what you want IMO, you NEED both to get a respectable time in a 305 TBI.

 

beast, wouldn't that mean you gained 1.23 seconds (16.0 - 14.77)?

i'm thinking gears and posi because of the wheelspin. my near stock firebird spins like hell with the single traction rearend, and that's with 3.08s! seems to me that increasing horsepower and torque would make the wheelspin even worse.

maybe i'm wrong. i haven't done it in a 3rd. gen fbody yet, but in every other car i've built i followed the old saw about "building from the bottom up" .... suspension, brakes, chassis before engine.

 

Well, there is more than gears and posi to deal with wheelspin. Gears definately will only make wheelspin worse, posi is a great thing and I coudln't imagine owning a car without it. The same can be said for a manual tranny as well IMO, but last night I drove a friend's ATI prochargered 4.3 V6 S10, WOW, it's an open rear with 3.42 gears. It might spin one wheel through all 4 gears (auto) from a dead stop, but it'll smoke most any 305 and probably most stock 350 TPIs from a roll. To me if you race timeslips at the track, the gears and posi might be better, but on the street the headers (or any hp adder) are better for the money.
QUOTE]Originally posted by seanof30306
beast, wouldn't that mean you gained 1.23 seconds (16.0 - 14.77)?[/QUOTE] Racing my car with 70* cooler water temp made at least .3 sec difference, as well as different track conditions and temp. make a difference.

 

i would do 3.73 posi first

 

actually you will usually find an increase in mph when you do a gear swap because the car is using teh power band more efficiantly in every gear. since it pulls through a stronger portion of the power band in high gear it creates more mph, it is sort of a false read to compare it to hp, but there is a gain from it.

later
tim

 

well, gears and posi do not make wheelspin worse. when i did the swap i did no other mods, i had a basically stock LO3. i could spin through first EASILY with the 2.73 open rear, but with the 3.73 posi rear i couldnt spin unlessi powerbraked it or was on a slick road. posi more then makes up for the gears in the traction department. are you sure that supercharged s10 spun through overdrive (4th gear in that auto tranny)? it seems hard for me to think that i vehicle that is just melting ONE back tire with hardly any weight on it is gonna be winning the race against a car that hooked. i think your buddy needs to invest in a posi - he would be happier

 

neither make more horsepower, but posi improves traction traction tremendously, and the stiffer gear improves torque multiplication.

actually, the gears are more for the future when you have more power, but it'd be crazy to go into the rearend to install the posi and not put the gears in at the same time.

bottom line? more horsepower does no good if it just goes up in a cloud of tiresmoke.

 

this whole thing about posi giving you such great traction when you do it along with a gear swap makes no sense. when you take such a step up in gear ratios (ie 2.73 to 3.42 or 3.73), going to posi doesnt even make up for the traction you lose, much less make things better.....of course that's not at all to say dont do it.....i can actually drive in the snow now

 

maybe i just got a shltty posi?

 

2 wheels pulling will absolutely give better traction that one wheel pulling. that's about as elementas it gets,

2 wheels pulling will almost always hook up better with bigger gears than one wheel pulling a shorter gear, too (within reason). my buddy just went from 2.73 single traction to 3.42 posi. with no other changes, it hooks up MUCH better. before he had to feather the throttle through most of first gear. now, it hooks hard off the line with a 2,000 rpm launch and you can floor it within 10 yards of leaving the line.

 

well maybe i have better traction than before but i still cant floor it in most of first gear.......

 

when i did my posi and gears i got more traction out of the hole, even though i went from 2.73 to 3.54's. blackbird got better grip with a 2.72 to 3.73 swap, i don't know where all you guys are losing traction from a posi with only a little street gear in it, you may wanna look to see if you suspension is beat or somethin.

later
tim

 

me, as well as many others, just stated it gives you WAY better traction. even with the rear gear change. maybe you have a 5 speed and are dumping the clutch, i am guessing that it will spin in that enviroment. i dont see a stock or close to stock LO3 spinning through first gear with gears/posi, at least not on a high(er) traction surface such as at the strip.

but thats just mine and few people i knows experiences....

im not calling you a liar, just explain the situation a lil more please....

 

first, it's an auto. second, it's not , if i sit at idle and mash the pedal, i will get no traction until about 4k in first gear. it was this way before the posi, and it's the same way after. i know the posi is working because of how it drives in the snow and rain when it's not being pushed. and yes, it's basically stock. it pisses me off, because my friend has a 94 GT - with more power - that grips like a horny 12 year old on a boner, but i cant get going to save my life. if you'd like to tell me what's wrong i'd be happy to listen.

 

it could be possible you are having suspension problems . . .

do you experiance wheel hop when you launch and spin the tires?

what about your tires, you 60' is only as good as your tires.

 

Get you some lift bar's I bet you wont spin then

 

two people have said suspension now.......can you be more specific? that's kind of a broad problem. the springs and shocks are in great shape so far as i can tell; the ride is still firm, the corners come right back to ride height with no bounce when you push on them.

yes there's wheelhop, sometimes it's worse than others, but it's not as bad as others ive seen

the tires are some kinda goodyear eagles (245/50/16) which for all i know are shltty for traction..... but there's plenty of tread on them

i'm really at a loss on this one.....

 

Are you positive that the posi is working in dry conditions as well, you say you know it works from how it drives on the snow but I thought that a failing posi may still work in situations where there's basically no traction available (e.g. snow) maybe the posi is failing, just a thought.

 

that's an idea, but it's brand new... has 1500 miles on it

maybe it never worked to begin with, but it's leaving 2 tire marks now.....as opposed to 1 before

i dont know of any sure way to test that

 

if you are getting wheel hop that you can feel sometimes that mean syou are getting soem degree of wheel hop all the time. look at your control arm bushings. if they are beat that can be one cause. how old are your rear shocks and what kind are they? beat rear shocks are one of teh most common causes of wheel hop, crappy shocks are prolly the second leading cause.
another place to look is your torque arm bushing. sometimes when they get beat they get all twisted up and you will not hear teh tell tale thump that so many people here when it lets go. jsut jack up teh car and give teh TA a few good tugs. if it feels liek it is mounted in pudding or makes thumpy noises you have a dead one. if you look at it and press your finger nail into it and it all dried up that is a problem too.
i dont' knwo if your car sits level or not, if the rear is sitting higher than the front of teh car it will ahve trouble transfering weight and the wheels will hop a bit.
if you have air shocks, get them otu fo there and your problem will disappear. air is a terrible damper, it is too weak(hel, i spend all day walking through it and i don't even get out of breath...lol, yes, i know it is a bad joke )
hope this helps you hook.

later
tim

 

When i first got my car it had some really bad wheel hop. So i put new shocks on the back and it all whet away

 

the suspension is all the original ws6 stuff. like i said, even though the car has 100k on it (officially as of today actually ) i think the shocks are ok, though most people would probably disagree. come summer i plan on doing lca's and a new torque arm anyway, so we'll see if that helps things. if not maybe ill replace the shocks and springs. thanks for the advice.

 

wheel hop in an fbody car is usually caused by a broken tranny mount this is very common and is do to a poorly designed torque arm and rear setup

 

I have a Blazer and regular some 4x4 boards and they all say posi rear ends suck cause they have a tendacy to explode. I find it really odd to come here were everyone seeks posi. On the 4x4 boards the thing to have is a locker...why isnt that the thing here?

I come here for the awesome engine advise..you guys rock!

I have 3/4 ton gear on my Blazer because the stock posi self destructed and didnt want to deal with it anymore. I dont think I'll break that 10.5" ring gear in the rear I have now but the guys on the 4x4 boards were persistant that I check to make sure it wasnt a posi before a bought it cause they explode just as easy as the 1/2 tons(10 bolt) do.


just a few thoughts

 

Okay....Where can I find a direct bolt on Posi and 3.42 gear. I don't know much about posi and gears so if you have any suggestion on how to make this easier for me let me know....
Thanks

 

The difference is trucks use the Eaton Gov Lock setup which is a pathetic waste of an attempt at limited slip that GM still hasn't been able to wake from and rectify which explode without warning due to there weak design. Cars use a more conventional positraction rear, Zexel Torsen if I am correct which work just fine. If a rear end is overloaded in any application it will explode, which is more apparent in a heavier truck. I too suffer the Gov Lock plague in my 92 but that will disappear eventually, along with the 10 bolt altogether when I rebuild my semi float 14 bolt I have kicking around.