I have a 327 with stock 300 hp, which I recently added a dual quad Edelbrock aluminum mani, with two Edelbrock 500 carbs and a set of flow tech headers,, it has a 12 bolt rearend with stock gears, which are doggy at best off the line,, ?? is would 3.73's add much to the performance of this setup?

I think it would help some. You really don't need dual quads on a stock 327, unless it has 11 to 1 compression or a big cam.

its not what you "need" per say, but whats you want and what looks cool, imo there aren't enough dual carb small blocks around.

3.73's should make a big difference, or so from what I've read, but you have to make sure your tranny is up to it, if you have a stock converter you wont see as big of a difference, than again with your setup you don't need that wild of a converter. I'm doing a muncie swap this summer first, than I plan on going with some 3.55's or 3.73's with a posi

2.73's and dead hooked ran a best of 13.51 @ 101.7 using 1st and 2nd only.
2.73's cruise at 65 and 2300 rpm.
Swap to 3.73's and ran a best of 13.2 @ 103 spinning, but used all 3 gears.
3.73's and 65 is 3300ish rpm.

one thing to look into is what kind of shape are your valve springs in?? adding a bunch of gear will take you up into valve float sooner ...but it sure is fun :)

Doug what are your drivetrain specs? - i have 2.73's right now and am going to upgrade to 3.73's w/ a posi-unit soon... i have a 70 chevelle with a 350,holley 750 dp, torker II, 441 heads(soon to be 461 w/ 2.02's), 284 adv duration-480 lift cam, 3200 stal turbo 400. im not sure what the car runs now (low 14's high 13's probably) but i would like to have it in the low 13's. could this be acheived with my motor, tranny, and new rear end? thanks

At the time with 2.73's
400 +.030 = 406ci
Stock heads 1.94/1.60 and a home port and polish job.
280H compcam (.486 I/E)
1.5 rockers
Torker intake
750dp Holley (list # 4779-6)
th350 w/ 2200 stall and a transgo shift kit
stock 70? 8.2" rear with 2.73 posi (fresh gear lube and posi add.)
1968 Camaro 3480 lbs. (w/ driver)

As for your spec and new gears, I would say mid/low 13's very possible with traction.

thanks thats what i was realisticly wanting to hear

I did assume at least 9.5:1 compression .

yupp