First off, the car in question is a carburated 2.8L V6 that in a year, or later, I plan on switching to EFI and possibly 3.4L.

The questions I have are:
Is a posi rear worthwhile on a 2.8? And
does anyone make a STB for a carburated V6?

Thanks
--------------------------------------------
Jurrel
1984 Pontiac Firebird V6 2.8L
Bone-Stock

 

Sure a posi rear is worth it! And if you can get an axle with a lower gear ratio than what you have now, you'll see even more get-up-and-go out of your car. I -think- your car has a 3.23 rear gear in it. If you can find an '83-'85 Z28 or Trans Am in a junkyard with a 5 speed, look underneath, it'll have a 3.73/posi/disc rear axle. That's the one I put under my car. Beware that 82-88 rear discs had a recall out on them, you can get the recall kit for $45 from http://www.gmpartsdirect.com . The 85-89 2.8's with automatic trannies got a 3.42/open/drum rear. And if you see a 4 cylinder firebird/camaro in a junkyard with a manual transmission, it's got a 3.73/open/drum rear. The '84 Camaro HO also has a 3.73/open/drum rear. An 84-up rear axle will be ideal, because 82-83 f-bodies still used standard SAE threaded brake lines; GM went to metric thread brake lines in '84. There's a couple options though if you do find an 82-83 rear that you want to use... but I won't bother going into 'em in detail unless you -do- want to know.

But I'd say if it were between posi and lower rear gears, go for lower rear gears. Gears require a lot of settings and expensive tools, combine that with the fact of installing the gears with wrong settings can destroy the $200 gear set immediately, you might want to pay someone to put rear gears in for you.

As to a strut tower brace for your carb'd car, check out the 3 point brace by Edelbrock at this link: http://www.edelbrock.com/automotive/suspension.html Not sure which one you'd use, but go ask (or do a <a href="search.php?s="><img src="images/top_search.gif" alt="Search" border="0"></a> on the suspension/chassis/brakes forum. Our cars are identical suspension-wise to the v8 guys so everything that happens in that suspension/chassis/brakes forum will apply to your car.

 

I've seen the 3 point STB's before, they are made to go over the
upper Plenum I think it is....And that sits lower then the air cleaner
so as far as I know, that doesn't work, least not that I have seen.
I mean if someone has done it, then I'd gladly say I was wrong, then
go buy one

 

I don't think they will work with a carbed engine. At least I have not seen one that will fit.

 

If you're going to do a carb to EFI conversion...I wouldn't fool much with it, I would just drop a low mileage 3.4 in. Drops right in, not much hassle, and instead of 135 horses and..what..165 ft lbs from an EFI 2.8...you get 160 horses and 200 ft lbs..a much better building block. Look for the 3.4 swap boogie I think it's called...it's been all over these boards for a while now..many a satisfied V6er can attest to it.

 

Well I want more Torque not horses....I like the fast acceleration over high top speed.

 

The 3.4 accels for both horses and torque...

2.8: 135 horses, 160-ish ft lbs.
3.1: 140 horses, 180-185 ft lbs.
3.4: 160 horses, 200 ft lbs.

 

Well I figured the 3.4 raised both, but most folks from what I see are intrested in the horsepower raise...jus stating the fact that all Im really after is the acceleration...90-100Mph is fast enough for me.

 

Ditto..I don't care about horsepower as much as I care about torque. Which is why I couldn't stand an import. Decent horsepower, but most are severely torque deficient, not to mention the shoot me now I'm as slow as a Mini bottom end those 4 bangers have. They dont move until they hit 3500 rpms.

 

By the way...low rpms is the area of torque, but once you get upper end, it's all horsepower from there. Torque peaks out in the 3000 range...3400 or so on my 3.1 I think.

 

for quicker acceleration, use smaller sidewall tires. For an EFI conversion alternative, get the edelcrotch base w/the 4bb top & slap on a Holley or Accel efi kit.

 

Yup..lowers effective gear ratio and handles better...but gives a stiffer ride and the smaller the shorter the sidewall, the more expensive the tire.

 

Just an opinion. Even though they don't lower the effective ratio (as badly as my v8 could use it), the 235/60r15's on my new camaro's stock 15x7s are something I'm absolutely in love with. Even with the 255 ft-lbs of torque at 2400, all I have is neck probs, not traction probs... at least when it's bone dry outside no, officer, I really was trying to go forward, it's just all this water picked up my car and made it *float* backwards.. yeah.. wet uphill stop signs suck

I'm not sure posi is a worthwhile investment with a 6, though.. I had a very very tough time ever proving a need for it. Only when it's wet would I even think of dumping that kinda cash for my 8.

Just an opinion.

 

I can certainly attest to the fact that the 3.4 will make a massive improvement. I took a '95 3.4 and replaced the dead 2.8. Swapped in a 5 speed at the same time and the difference is unbelivable. I'm not going to boast as much power as a 350 car, but the 3.4 will suprise you (especially WOT in first or second).

 

Heh I know the power a 3.4 can have My house-mate has a fiero...he had to replace a 2.8L with a bad head gasket...he put in the 3.4 and man that hauls.....

As to the edelbrock manifold with a 4 BBL carb...all the ones I have seen for a V6 are NOT EGR....which I need :/ (living in California)


And to the tires, yes I'm still stock on the 205/75R14's....I plan on something in the 225/60R15 range though in the semi near future....don't want to over do the width on the tires.