Hello,
as the title says I would appreciate some advice on rear ratio for my setup.
Have not scaled but I'd bet the car weights less than 3000 lbs. Believe something between 2900 and 2950 pounds.
The 4 speed manual gearbox ratios:
2.92:1 -> 2.03:1 -> 1.42:1 -> 1.00:1
The tire:
245/60 R14 regular street tires (about 25,57 inches of diameter)
The rear axle:
Dana 44 with the option of ring sets from 2,xx up to 3,73:1.
The engine:
318 LA block, ported iron heads with bigger 2.02" and 1.60" valves. The compression is about 9.4:1 with a regular gasket.
Important notes about the head:
-Don’t know if the head casting is the same of yours from the 60’s and early 70’s, but I think they are.
-Also don’t know if the porting job is good or bad, can’t flow heads here. I do believe they’re at least a little better than stock, by looks.
I have a programmable Electronic Fuel Injection (EFI) thing that also controls spark timing without a distributor, so I believe the engine will be more docile and better to drive than what it would have been with a carb. It has an Air-Gap intake modified to fit the throttle body and 8 fuel injectors for the EFI, has Summit ‘Block Huggers’ short tubes 1-5/8” diameter exhaust manifolds, 2.5” dual exhaust with H-pipe and mufflers.
The camshaft is a Howards hydraulic (int/exh) 265/273 adv, 218/226 @0,050” with 0.502”/0.525” lift, LSA is 110º. RPM range says 1800-5600 but I don’t know for which engine (318, 340 or 360). Lifters are Comp Cams ‘ Pro Magnum’ P/N 867-16 (a higher RPM, higher abuse type of hyd lifters. No relation with the Mopar Magnum name) and I have some old adjustable rocker arms with ball/cup pushrods (think they came from those 273’s).
The point of the car:
Although it’s a light car it has everything inside: bench seats, power steering, power brakes, will buy an air conditioning system, will have some radio. It is smaller than a Chevy Nova. As you might have figured I’m not in USA. I’ll not drag race it, but I do want some of the punch, some of the ‘muscle car’ thing in it. That’s why I chose that gearbox ratio (the other option was a close-ratio). My goal is to have it going strong/fast from first through third gear and have the fourth to drive at 65 mph without having the engine screaming at trips. But I have no other car to compare with it, so I wanted to ask you who have had experiences with different rear end ratios, vehicle weights, close and wide ratio gearboxes…
Initially I thought about 3.07:1. Then thought it might be too long and thought about 3.31:1… maybe 3.54:1. I’ve read a lot of threads on this and other forums, but you guys usually have way heavier cars with close-ratio gearboxes and who-knows-what tires, so I can’t compare.
I’ll stop, sorry it’s too long. Thanks
Hello,
as the title says I would appreciate some advice on rear ratio for my setup.
Have not scaled but I'd bet the car weights less than 3000 lbs. Believe something between 2900 and 2950 pounds.
The 4 speed manual gearbox ratios:
2.92:1 -> 2.03:1 -> 1.42:1 -> 1.00:1
The tire:
245/60 R14 regular street tires (about 25,57 inches of diameter)
The rear axle:
Dana 44 with the option of ring sets from 2,xx up to 3,73:1.
The engine:
318 LA block, ported iron heads with bigger 2.02" and 1.60" valves. The compression is about 9.4:1 with a regular gasket.
Important notes about the head:
-Don’t know if the head casting is the same of yours from the 60’s and early 70’s, but I think they are.
-Also don’t know if the porting job is good or bad, can’t flow heads here. I do believe they’re at least a little better than stock, by looks.
I have a programmable Electronic Fuel Injection (EFI) thing that also controls spark timing without a distributor, so I believe the engine will be more docile and better to drive than what it would have been with a carb. It has an Air-Gap intake modified to fit the throttle body and 8 fuel injectors for the EFI, has Summit ‘Block Huggers’ short tubes 1-5/8” diameter exhaust manifolds, 2.5” dual exhaust with H-pipe and mufflers.
The camshaft is a Howards hydraulic (int/exh) 265/273 adv, 218/226 @0,050” with 0.502”/0.525” lift, LSA is 110º. RPM range says 1800-5600 but I don’t know for which engine (318, 340 or 360). Lifters are Comp Cams ‘ Pro Magnum’ P/N 867-16 (a higher RPM, higher abuse type of hyd lifters. No relation with the Mopar Magnum name) and I have some old adjustable rocker arms with ball/cup pushrods (think they came from those 273’s).
The point of the car:
Although it’s a light car it has everything inside: bench seats, power steering, power brakes, will buy an air conditioning system, will have some radio. It is smaller than a Chevy Nova. As you might have figured I’m not in USA. I’ll not drag race it, but I do want some of the punch, some of the ‘muscle car’ thing in it. That’s why I chose that gearbox ratio (the other option was a close-ratio). My goal is to have it going strong/fast from first through third gear and have the fourth to drive at 65 mph without having the engine screaming at trips. But I have no other car to compare with it, so I wanted to ask you who have had experiences with different rear end ratios, vehicle weights, close and wide ratio gearboxes…
Initially I thought about 3.07:1. Then thought it might be too long and thought about 3.31:1… maybe 3.54:1. I’ve read a lot of threads on this and other forums, but you guys usually have way heavier cars with close-ratio gearboxes and who-knows-what tires, so I can’t compare.
I’ll stop, sorry it’s too long. Thanks