1st Gen Tacoma 4.56/33’s

I recently fitted 33’s on my first gen 1998 Toyota Tacoma. It’s the 2.7L 4x4 but I have it turbocharged. My stock gears are 4.10 and I was thinking of changing to 4.56 or finding a stock 3rd member (front and rear) to swap in with 4.30 gears. I would prefer to keep the RPMs around 2500 driving down the highway so I am not in boost generating hot IAT’s. Anyone have any input?

Here is my current gear to speed rpm ratio:

4th gear
55mph:2050rpm
65mph:2450rpm
75mph:2900rpm

5th gear;
55mph:1750rpm
65mph:2000rpm
75mph:2250rpm

 

You have positive intake manifold pressure at 2500 when cruising?

Aside from that, as long as you're not overboosting (surge line) and have an intercooler, you really shouldn't be ingesting much extra heat. Are you monitoring this?

 

No I dont create boost at 2500 but I don’t want to drive around over that rpm because that’s when I start to hit boost. My intercooler does a good job now I just don’t want to heat soak it. I am more curious to hear what other RPMs people are getting with 33s and 4.56 gears

 

You can use online RPM calculators to factor in gear ratio and tire size, and know quite precisely what RPM you'll be at at a given speed.