Conditions for downshifting from 3rd to 2nd at WOT with 4.10s

[SIZEMOREMK]

What speed is too fast to downshift into 2nd when going WOT with the 4.10s.

Trying to figure out what I should ask for in my tune???

My MM just received a set of 4.10s and a dyno tune from Martyo :D

These guys are top notch! I see why they have such a good rep!

He and Jeff are still working with me on the details of the shift schedule and such since I picked it up in rush hour without a good chance to evaluate the tune properly. They've already sent an adjustment, but before I bug them again I want to make sure I'm not off base with my 3-2 downshift expectations.

The existing tune had issues, but with the 3:55s from a cruise of probably up to 85MPH, if I hit the O/D off button and nailed it, the car would hit me with a pretty violent 3-2 downshift (which I enjoyed).

With the new tune and 4.10s, the car does not downshift to second the same. I'm not sure what speed is too fast to downshift into 2nd with the 4.10s. Or when I get into the beating on the car too much category???

Mathematically, 80 MPH puts me close to 3700 RPM in 3rd, which would be 5700 RPM in 2nd, which I would think is enough left over for the kick in the pants at from 5700-6500 ish.

The other benefit would be that a 2-3 shift at 90MPH and 6400 RPM puts me at 4100ish RPM in 3rd which is alot closer to peak torque.

Going WOT at 70-75 in 3rd at 3200-3400 has me well below peak torque...

So I think I would like the car to downshift into 2nd up to 80 MPH, but I would think at least 75MPH?

What are ya'lls thoughts?

Thanks gents!

[captain]

Seems too fast to me. let Mo help you decide. Under the right (wrong) road conditions this could prove terminal. I dont think Marty would allow a mechanically hazardous shift point out off the shop. But... again consider the road and pavement issues.,"Crashing" cause your car works too good isnt his fault. My 4/10 gears are pretty spent by 80 or 90 mph I think you should be in third at 70 plus.

[SIZEMOREMK]

Seems too fast to me. let Mo help you decide. Under the right (wrong) road conditions this could prove terminal. I dont think Marty would allow a mechanically hazardous shift point out off the shop. But... again consider the road and pavement issues.,"Crashing" cause your car works too good isnt his fault. My 4/10 gears are pretty spent by 80 or 90 mph I think you should be in third at 70 plus.

These are the kinds of inputs I was looking for.

I've bothered those guys a pretty good bit in the last coulpe of weeks.

Trying to force myslf to leave them alone :o

[fastblackmerc]

Seems too fast to me. let Mo help you decide. Under the right (wrong) road conditions this could prove terminal. I dont think Marty would allow a mechanically hazardous shift point out off the shop. But... again consider the road and pavement issues.,"Crashing" cause your car works too good isnt his fault. My 4/10 gears are pretty spent by 80 or 90 mph I think you should be in third at 70 plus.

What do you mean by spent? :confused:

[Curless]

When you shift down from a higher gear into any gear I would want at least 2000 rpm until redline, I would not program my car to do anymore than this because it would then d it all of the time. If you wish for it to drop back more once in a while, then manually shift it down.

[captain]

The 4/10 gears suit my driving style well... the 0 to 60 is much improved. It climbs up faster.
However by 80 mph they are dependent on the motors ability to generate rpms.
the engine is stock.they are just gears at that point.
I remember the old gears...
that stupid thing would go to 100 120 pretty fast.. But you had to wait till you were at 50/60mph Made for one helluva passing machine!