Projects Dont gear those old sixes like a V8

I have a 37 Chevy p/u with a 235 and 2 years ago installed a T-5 and granada 8 inch along with suspension and brake upgrades,I figured since those sixes are good for torque it would work good with the 2.79 gears but thats not the case. I was also figuring better gas mileage but it actually got worse but was able to tune it some and the mileage improved but it just was not right,I picked up a rebuilt third member with 3.55 gears and much better but still need to drive it some more but there is still too much salt on the roads for me to take it out for longer drives. The more modern straight sixes might be able to work with highway gears but not those old 235s and now I will probably have to do more tweeking on the carb since I leaned it down some for those too tall gears,I cant wait untill the snow goes away so I can drive it more and the T-5 improved the truck but the better gears will even make it better.

 

My late 235 4spd really improved all around with a 3.73 set

 

I read in the patricks catalogue about running ( I think ) the 2 groove 4spd saginaw with gearing around 3.73 is supposed to be the ticket.

I was also told by an old timer that has built these stovebolts for years that the t-5 is not a good option because in 5th the rpm's drop so low that you loose vacuum and that's why your mileage suffers. said it is out of its power band?

now that said, these are things I was told not things I know as truths, but something still to think about...

 

Figure out how fast you want to cruise, and gear it so the engine runs 2100-2400 rpm at that speed. If traffic or a hill means you are going slower, use fourth gear.

 

I agree with the 373s. My 235 is running the T-5 and 373s. Seems to be a good combo.
Dom

 

I put a softer spring in the power valve when I was tinkering with the carb and yes the motor was way out of its power band with the 2.79s,I never used 5th with those tall gears and never could use 4th under 40 so I cruised around town in 3rd but now 4th wont be a problem. Got it up to about 45 and put it in 5th and alot better,I had to leave it in gear longer before shifting but now it seems normal so as soon as the snow melts its time for some longer test drives and see how the plugs are burning to see if I have to play with the jet some more.

 

My 235 in a 54 210 has a howards cam and higher than stock compression. It likes 2500 rpm to cruise at. It will deliver 25 mpg on the highway. it will pull down to almost idle in high gear and still accelerate, slowly, ha.

I do run a 1:1 trans and 2.93 gears. Crusing speed is about 70 mph @ 2500.

 

I'm runnin 3:90 in my in my truck also a 235 with a t-5,rpm's at 2300 at 70.I think somthing in the 3:70 range would make better use of 1s gear,I would keep he gear choice between 3:50 to 3:90,just my 2 cents.

 

I think you are discovering that torque does not equal horsepower.

 

Ok Im glad I seen this maybe you guy's can help me out not trying to highjack but my problem is Im running a 235 in my 51 belair, turbo 350 ,put a 8.25 nova rearend with a 273 gear and it sux any suggestion's on the right gear combo with the 1.1 trans should I go 308,336,or342 any help is app thanks

 

3.36 or 3.42 would be better.

 

I run 3.90's and a t5 behind my sprint 6 and it works great!

 

I ran 3.55s with a 4 speed and 30" tall tires, worked nice for my my 55.2. Cruised at 65 comfortably, had more if needed. Guesstimate probably 22-2500 rpm.

Devin