I plan to install a LT1 cam from a 96 Z and an Edelbrock TBI intake this summer but right now i want to upgrade my gear ratio (currently 2.73). What would be the best gear for my setup. These gears will be going into an SLP take off posi. I was initially going to go with 3.73 but i want to make sure that the gears arnt going to throw me out of my powerband with the new cam, if that is even going to be a problem, i dont know, i guess thats the reason for the post.

:lala:

 

most people here will say 3.73s are ideal but you could find a v6 rear end with 3.42s and save a couple hundred$.

 

hey I see you have a hooker catback. I want to know what it sounds like. I am looking for a catback with a nice deep mellowed out tone. My brother has an American Thunder Flowmaster on his 305 tpi and it sounds sweet! If you have an info on cat back sounds let me know. Thanks

 

4.10's hehe
it really boils down to how much intoracing vs street manners you are into. using the basic 245/50 16 tire here are some rpm's for different gear ratios at different speeds(all based on being in 4th in a 700r4, convertor locked)
35mph 45mph 60mph 75mph
3.23 1050 1350 1800 2200
3.42 1100 1400 1900 2400
3.73 1200 1550 2050 2600
4.10 1300 1700 2250 2800

htese are not perfect numbers, but very close estimates. as you can see even with 4.10 gears cruising at 70mph you are still well below 3000 rpm. the image that a little more gear makes your cruise rpm a lot higher is a bit exagerated as you can see. and from what i saw when i put 3.54's in place of my stock 2.73's it looks like it really has very little effect on your highway mileage, mine didn't even change. your aroudn town mileage will suffer as you explore how hard to launch from lights with your quickness

later
tim

 

the gears will not throw you out of the power band either. the idea at the track is to run past your peak hp just as you get to the traps. with 3.73's. with the LT1 cam you are looking at putting peak power around 5400 rpm, that means you woudl hafta get a 113mph exit speed to run past peak power. i'd say the gears will leave you right in the meat of the power band and pulling hard through the traps since the cam will likely put your trap speed around 100-102(4900-5000rpm in third).

later
tim

 

Thank you for the info, this is exactly what i was looking for, i guess ill be going with the 3.73s. THANK YOU

And about the Hooker cat-back, i love the sound. It is quiet at idel and cruising but once you put your foot on the gas it has a beautiful deep roar, especially when you open it up. Sorry i dont have any sound clips but i would recommend getting the exhaust as well as many other theirgeners would. I know on the exhaust board someone is trying to get their site fixed so that they can post their Hooker cat back clips, so you should try there and also search the boards.

 

I have a 91 305 5 speed, it came with 3.08 gears stock, my question is what gears do you recomend with the 5 speed, I was debating between 3.42 or 3.73's. Does anyone know what RPM I would be at in 5th gear going 70 mph with either of these gear ratios?

 

go to the search button and type "3.73 gears 5 speed" or something like that, and just read the posts, this board has everything, sometimes you dont even have to ask.

 

I'm not sure about 70mph, but here is 80 mph, estimated.

3.73: 2425 rpm @ 80 mph
3.42: 2220 rpm @ 80 mph

I am basing these calculations on my 5 speed with 3.08 gears. I cruise at 80 mph at about 2000 rpm. Here is how you can figure your RPM at any speed.

new RPM = (current RPM) X (new ratio) / (current ratio)

hope this helps, Eric