If you are planning a whole rear end swap, you might want to consider using a rear out of a 2nd gen car. Should run around 2600-2700 RPM at 60 MPH where a 3.55 would run 2900-3000 or so (ballpark numbers).Īlso, keep in mind that if you are simply planning on changing gears that you can't go any higher than 3.23 without changing the housing, or so I've read. Does anyone have any suggestions on what is a good ratio?Ī: I just went through the same thing with a 2.56 rear and picked 3.23 as a good all around ratio. I do mostly around town driving but occasionally go out on the highway at 60-70 MPH. I am thinking of putting in either 3.23 or 3.55 gears. I don't really want to modify the engine or put in a higher stall converter. I presently have 2.78 gears and the car is pretty doggy. Non-stock changes are - TH400, transmission, Rochester Q-jet, headers, P22560 tires and cast iron Pontiac intake. I have a '68 firebird convertible with a 350. I'm looking for recommendations for the optimum gearing on my differential. Q: Choosing the right gear ratio - revisited Now look at your table of gear selections and choose the one closest to 3.14. What I'm looking to achive is a car which will cruise nicely at 65 MPH, and accelerate like it was shot out of a cannon from 65 to 90+ for passing.Īny ideas as to how to go about choosing the right gear ratio for this task?Īs an example: Let's say your 400 motor runs very strong at 2,800 RPM and your rear tire diameter is 24.5 inches. The car is mainly driven on the highway, between my home and our cabin. As I understand it, you get better top end speed with the 2.56 gears and better off-the-line launches with the 3.9 or 4.33 gears. With this work in my current 10-bolt housing? If so, the next question is what gear ratio to go with. I'm fairly certain I'd like to go with the factory POSI/Limited Slip carrier. The car also a healthy 400 with a turbo 400 trans. It currently has the stock 3.08 open rear end in it. I've been contemplating a rebuilt of the rear end in my '67 Firebird.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |