Need help to understand what to do reach max speed on 91 SHO+

[mavericksav]

What kind of shape is your exhaust system in? Wind can make a big difference; Did you run your top speed pass in two directions to check to differences?

stock exhaust, run only one way (it was hi-way) to my home

 

[mavericksav]

What tire size do you have on the car (stock?), that can affect the speedometer reading

215/55/16 I used GPS to check speed

 

[mavericksav]

Aerodynamics. You don't have enough power to push the car through the air any faster.

why? top power is at 6200 rpm and my top speed only at 5400-5500 rpm

 

[luigisho]

Unless you increase output substantially or reduce the physical characteristics of the vehicle itself (weight,shape/aero, etc) the extra whatever is missing is not enough to get you to 160. You need close to 300hp without changing the vehicle.

https://robrobinette.com/top_speed.htm

 

[zak]

The newer (96 to 07) SHOs have a bottom engine cover. Should bolt on if you've already done the Gen 3 subframe upgrade. You will need to also cover the space from the lower bumper bottom edge to the bottom cover. Take the windshield wipers off, tape all the seams, etc.
Also, the rear bumper cover is like a parachute on these cars, might fashion a cover there as well

Also, to sperold's comment on Ernie's engine, it was a 90 mm overbore of a 3.0 L block (not a 3.2L) that he "cheater destroked" by using undersized rod bearings and doing a slight offset grind, this got him back down to 29XX cc's which he needed to be legal in F Production

 

[firebat45]

The newer (96 to 07) SHOs

You must either mean 96-99 SHO or 96-07 Taurus