96 on 35's lacks power.. need help

[white_trash88]

Anyone on here have a 5 speed or able to chime in on this? It's a daily driver so I would like to keep fuel somewhat ok. But need power to tow with.

35s and a 5 speed with 4.56 would be more than enough on a 350 but being a 305 you'll probably need more like 4.88s or 5.13s.

 

[Beast96]

Its getting a 350 this weekend or next. I have the engine just waiting for a tune. But im not so sure what gears I have anymore. Based off of 70mph in 4th gear im around 2600 rpms and lower but no power in 5th

 

[white_trash88]

Its getting a 350 this weekend or next. I have the engine just waiting for a tune. But im not so sure what gears I have anymore. Based off of 70mph in 4th gear im around 2600 rpms and lower but no power in 5th

I personally know of a 350 TBI that with road em for days and still pull 16 mpg with a 5 speed and 4.56s I can only imagine a vortec. I'd say open the trans up and check all the gears this weekend too if you can.

 

[90halfton]

Its getting a 350 this weekend or next. I have the engine just waiting for a tune. But im not so sure what gears I have anymore. Based off of 70mph in 4th gear im around 2600 rpms and lower but no power in 5th

Jack it up and spin the tires by hand and count turns of tire vs turns of driveshaft. That will tell you your gear ratio.

 

[white_trash88]

Jack it up and spin the tires by hand and count turns of tire vs turns of driveshaft. That will tell you your gear ratio.

I'll bet its got 3.73 because I'm pretty sure all 4x4 305 trucks came with 3.73 to compensate the low power output

 

[90halfton]

I'll bet its got 3.73 because I'm pretty sure all 4x4 305 trucks came with 3.73 to compensate the low power output

You're right. Someone could have swapped em out for who knows what reason though. Hate to spend alot of money on axles and/or rebuild parts just to get em apart and realize some ******** put 3.08 axles in it and maybe I didn't want to make the leap to 4.88's after all. Just takes a minute to jacker up and look. That's how my luck works out lol. Almost definitely is 3.73's though.

 

[Beast96]

I personally know of a 350 TBI that with road em for days and still pull 16 mpg with a 5 speed and 4.56s I can only imagine a vortec. I'd say open the trans up and check all the gears this weekend too if you can.

I know the trans is good and can handle abuse it's a nv 3500 it's getting new slave and clutch before it goes back together

 

[Beast96]

I'll jack it up tomorrow if I have time but most important thing on my list is the fuel pump so she drives again barely made it home today

 

[Beast96]

Still leaves me with no solid answer on what gears to use. I was told anything from a 4.10 up to a 5. Something but that was for a 350 tbi auto 4l60e

 

[white_trash88]

All the calculations said 3.75 with that rpm at ~2600 rpm doing 70 with 35s