Deciding on a gear ratio

[69grande351]

Hi everybody, I have decided to go with the gears. But I don't know what kind of gear ratio i should get. I would like to go on the highway sometimes, but dont want to blow my engine up. So do you think 3.55's would be a good choice? Also, do you think I should get a posi? Or should I wait and upgrade to a nine inch later on and then get a posi with that. I will not be on the drag strip so the et times arent a factor. I also want to but a 600 cfm Holley carb and edelbrock manifold. Is that a good setup? Would my car be faster with the gears, carb and manifold? It has the stock 302 w/auto and the stock 2v carb. Thanks everyone.

[rbohm]

first save your money by not upgrading to a 9" rear untill you need it, and likely you wont untill you get over the 400hp mark with slicks. a 3.55 gear is a good one to use for a decent compromise between street drivability, and performance, just remember though that at 65 you will be turning better than 3k rpm so fuel economy will suffer somewhat, and noise levels will be higher. you can alieviate that by swaping an o/d trans at the same time. as for the carb, the 600 is too big for a stock 302, in fact again untill you get over the 400hp mark you dont need more than 500cfm airflow. that said however you can make the 600 cfm carb work if that is all you have or are planning future upgrades.

[rwhite65]

I agree, the 9 inch would be way overkill. Personally, the best way for u to switch gears is to buy the whole carrier....of the ratio u like best, with the posi already installed. Then u can put it in urself and save the installation costs.

I do not theink the 600 will be overkill....but maybe more then u need. I think the 600 will be a good choice for you...gives u room to grom in the future.

With the gears u will feel the difference. Ur next best bet would be exhaust and/or a shift kit if u do not have one already.
Ryan

[Rev]

I use a 625 Road Demon on my 306 and its just right. On a modified 351W, I think a 670 Avenger or even up to 750 would be OK for the 351W(depends on mods). I assume we're talking vacuum secondaries here. They are much more forgiving due to the fact that the secondaries only open on an "as needed" basis. I would never put a 500 CFM on a 351.

Rev

[era427tp]

I have had good results with the 1-191 Holley,and after headers a 570 Holley street avenger on a 289.

[Rev]

I agree that the 570 Street Avenger is just about right for the 289. I think a modified 351W needs more though.

Rev