I have heard time and time again that 373s will hurt perofrmance instead of help it out in my 305 5-speed? is this true.

i have to choose between 3.43 and 3.73, i wan my swap to be worth it and seeing as how I have 3.23 right now swapping to 3.43 will give me a very littl increase.


so whats the verdict? 3.73=too much or go for it?

 

some on the boards have 350 tpi autos with the 3.73's and are mid 13s in the 1/4 mile. most only have a few mods also.

 

3.73's should be fine. The problem that I have heard is that the older TPI systems cannot work properly with 4.10 gears but I'm not sure how true that is. Plus the problems that these would create, you have resolved by porting your system and adding the SLP stuff. I'd say go for it.

 

seeing you have the stock cam and heads i dont think it would be worth it to put in 3.73's. its all about getting the right combination. i would keep the 3.23's . if you plan on doing a cam and head update that would be a better time to do it. a cheap zz4 cam and port your heads would really wake up your car , then maybe a gear change. hope this helps.

 

As long as you don't have to shift into 5th before the end of the 1/4, you'll be fine. The only negative that you will see is a small decrease in gas mileage. I don't remember exactly what the T-5 ratio's are, but the main thirdgen site has gear calculators and the ratio charts listed somewhere. That will tell you exactly what you need to know as long as you know your tire size and approx. shift point/powerband.

Good luck

 

alot of mechanics around my area tell me to go with 3.73. or 4.11 because the over drive in the t-5 helps out with the gas mileage and the speed increase in the 1/4 will be noticible

 

well if shifting/quarter mile matter.

From what I undertsand you are supposed to be @ the top of 4th when you finish a quarter mile run, I am only @ the very top of third @ the end of a quarter mile pass, thats why I think I should upgrade.

Vortec heads are in the future as well as a cam & 1.6 rockers...soon .

 

i'm just shifting into 4th with 3.08

 

I am already shifted into 4th and I do the quarter mile at 97 mph. I have the 2.73 gearing.

 

Stay with the 3.23's. Sure you have 5th gear but that low of a gear with stock cam and heads will put you out of your rpm powerband real quick. Your stock TPI and cam isn't good for anything past 4500 rpm, those low gears will top you out too quick.

 

I can tell you from experience that 4:10s are too much. They give you great stop light to stop light torque but that's it. If you go with bigger cam, better flowing base and runners, then 3:73's might be ok.

 

I think you'll be fine - look at it this way, if the 3.73s do anything they will help 1/8 mile times... if they wind up putting you out of your powerband to fast, then you have justifiable reasons for MORE MODS

 

do the listed mods first and then put gears in.
or if you 're planning od doing the mods soon, put the gears now

 

I am runnig 3.73 gears and am very happy with them. Although I have a 700R4 trans. I put the 3.73's in before I did the exhaust, converter, and supercharger, they made a great difference in low end acceleration. But then again I had 2.73's. Anyway, 3.73's will not put you out of your power band, they are a good gear for the street car that sees the strip on occasion.

 

My 4.11 works great for me. Great for the quarter, But it is not ideal for highway useage.
I think a 3.73 will improve your quarter time.
you will have to calculate your RPM's at your normal highway running speed to find out if you can live with it.

Happy modding