3.73 gears to much for my small block?

i am looking to step up on my gear selection in my el camino from the stock ring and pinion and i was talking to a buddy and he was saying that 3.70's in my car thats only making about 320-330 hp would be over kill and i wouldn't have any top speed or it would be greatly reduced is this true and about how much would i loose off the top end  

what kind of transmission do you have , 3.73 are in my opinion are the best balance for street/strip.  

its a th350 and i shift it at 5500 but going with the 3.73's about how much top speed will i loose vs. my stock 3.08's or whatever i have stock in there  

What is the O.D. of the tires.  
Horsepower sells Engines and torque wins races.

about 26 inches  

Going from 3.08 to 3.73 gears you will lose approximately 23 m.p.h. at the 5500RPM shift point.  
Horsepower sells Engines and torque wins races.

??? so your saying instead of going 105 MPH in 3rd gear at 5500 i will only be going  82 ? ... wow that a pretty big difference what gears do you suggest i go with taking into account my mild engine and tire size ect and it being mostly a street car with the occasional 1/8 or 1/4 runs  

i believe that in my rear end i have how now has some where between 3.60-3.90 gears in it because i ran the mph and rpm together and the numbers fit better than 3.08  

You need to know what gear you have first. Does it see alot of interstate time?  

I have 3.73's in my Chevelle and they do fine, you will see about 3000 RPM at 70 MPH on the freeway though. I put in a 700R4 overdrive and it is hitting 2000 at 70 MPh @20 MPG!
With no overdrive you will definately notice the higher rpm's on the freeway but it's tolerable. I also shift at around 5500 1,2 gears. 3rd gear @ 5500 will get you through the lights quicker but you will just be shifting sooner that's all.  

4.56's in a weekend car is fun but rarely driven any length of distance at one time.  Depends on how you use your car what gear is best.  

Tyler,

The gears will really help your car perform, the mechanical advantage will help keep your engine where it is making power.

Assuming your TH 350 has a 2.52 1st 1.52 2nd and 1.00 3rd, with a Redline of 6200 RPM's using a 235 60 r 15 tire your top speed will be around 130MPH at 6200.

Shifting at 5500 will net you:

1st gear 45 mph
2nd gear 75 mph
3rd gear 115 mph

You will cruise around 3300 rpm's at 70 mph.

Using the stall converter we've discussed will also help the engine get into its power quicker as well and really help get you moving off the line.

What method did you use to figure your current ratio?

The best bet is going to be to pull the 10 bolts find the numbers on the ring gear and divide them that will tell you what your current gear ratio is. For example 12-44 = 2.73 or 41-11 = 3.73.

I would bet you have 2.73's or 3.08's.

Good Luck I hopw this helps.  

how much time would you really be crusing at 70mph anyways? in my 72lemans i had 4.10s out back with a th350 and it kinda sucked driving it around town but at the street lights when you need them it was worth it. i would go with the 3.73 unless its going on the e-way.  

i dont use the freeway that much but i still want the car to be driveable casue it is my daily drive but a racer on the weekends ...that being said is doing a gear swap will i be gaining any 0-60 time or lower 1/8 mile times ? or will it we very insignificant?  

Be careful about putting in lower gears if you don't have the traction to match.
I have seen it often where a lower gear is installed and the only thing gained is more wheelspin at launch.
If it is a daily driver I would go in a different direction for more performance.
Adding headers and free flowing exhaust is a good thing to do as it helps performance and economy. The other option would be nitrous in a small dose. Maybe 50-75 hp as this would be safe with stock pistons and give you a much better boost than any gear change and it is only on  when you use it at the track.
Once again you will have to have traction to match the juice added. When I added juice to my last car in any decent amount it would tend to spin the tires when the front end landed.