Guy's
I just installed new weights and springs in the governer of my TH350 thats behind my recently rebuilt .030 over 455. Full throttle pulls now shifts at 5700 RPM. Seems a little high for my comfort. However it's still pulling hard at that RPM. Whats everyone think a good/safe max RPM is? It's basicly stock valve trane other than springs and lifters. Flat tappet hyd cam.

Thanks

 

If it’s still pulling, I wouldn’t sweat it too much. How accurate is your tach? If it’s a factory tach, it might be much lower than you think.

 

I think the tach is spot on. We actually ran the wires from a new Innova timing light w built in tach out the hood into the window because I don't trust my tach.

 

5700 isn't out of line. Don't go much past 6000 without engine mods.

 

5700 isn't out of line. Don't go much past 6000 without engine mods.

 

The factory tach might be accurate at idle, I wouldn’t trust it at higher speed. The factory tach wasn’t very accurate when these cars were new. Install a good aftermarket tach, or borrow one just to verify. You might be worried about nothing.

 

I like mine to shift at 5000 RPM in Drive, then I can manually shift higher if I want.

 

Curious - What weights and springs did you install to get to a 5700 rpm shift? Just curious how light you went.

 

I bought a B&M kit. It came with 6 weights. Two each, heavy, med, light. I used one med and one light. It also came with 6 springs all different ranging from heavy to light. I installed the 4th and 5th lightest ones. If I go back in I will use two med weights and the two lightest springs.
I would like it to stay in first longer when under part throttle and shift a little sooner under full throttle.

 

I would suggest getting a different governor to play with. That way if you get things really screwed up you can always go back to where you started.

You can change part throttle shift points a couple mph by turning the tiny screw inside the vacuum modulator vacuum hose neck. At most, you will be able to raise or lower the shift points 2-4 mph.

If your going to play around with governor weights, you definitely need a good accurate tach. Make a couple full throttle runs, and record exact shift points. Don’t change anything until you have repeatable results. Change one thing at a time.

 

Right, I just went through this. I installed an aftermarket tach temporarily and took the car out. My factory tach was 1000RPM higher then the aftermarket. From what I've read, this is pretty common. I was however able to re-cal the factory tach against the other using the adjustment screw on the back.

 

FYI - There are actually 6 different weights included in the B&M Kit (P/N 20248)

 

Seems V8al is correct. The kit has 6 different weights, not 3 pairs of weights as I thought. They are stamped with a number (1-6) I didn't see with my old eyes. 1 being heaviest 6 being lightest. What is deceiving is that the shape of them does not dictate their weight. What I mean by that is what I thought were 3 pairs because of thier shapes, one of each pair is made of thinner material so is much lighter than its match. I actually used weights #3 and #5. I plan to go back in and change something to bring that shift point down. I don't care for that 5700. Think I should use 3&4 or 2&3? I would be more comfortable around 5200-5400.

 

Today I took the #5 weight out and changed it for #4. I didn't hook up the tach yet but it brought the rpm down a bit. I'm much more comfortable with it now. If I had to guess I bet it's more like 5500 shifts now. I'll post actual RPM when I test with tach.