Recalibrating A Turbo 400 Shifty Business

I recommend starting for 4500-5000 upshifts.
Just finished reworking the TH400 Governor in the 63 Pontiac Gp.
Have 5700-6000 rpm upshifts.
It's very Violent though.
I like super fast of course but there is also safety.
Its kicking the tail end out on Violent high rpm upshifts.
Suspension being maxed out.
Weak old shocks.
Have a new set bought coming from Summit Racing.
57-60 mph 1-2.
80-84 mph 2-3:upshifts.
Wanted 90 mph 2-3 but has so much torque it pulls right past 90-111 mph in just 2 seconds later in 3rd high gear.

Just a warning be careful.
Best handling GM cars stock on True street tires is the Corvette C4 & Pontiac Trans Am 2nd gens.

Will apply to others like TH350 , 700R4, and 200R4.
 
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Some pictures for Everyone.
They are actually a bit stressful to setup because you don't know what results you will have ahead of time.
Have to make a Judgement call seat of the pants and just do it.
My brain hurt for 2 days reading online old posts from 15,-20 years back on other forums.
 
It's a 1988 Chevrolet P30 Butternut Van Truck Turbo 400 never rebuilt yet I am using. Has held up nice so far to abuse by me. Think I have been using since 2016 year.
TCI Chevy to BOP Laser cut adapter plate to the Pontiac 455 engine.
Hughes 2500 Rpm HD Stall special built for Pontiac 455 engines.
Feels tight but flashes nice.
Could use another 300 rpm stall but I tuned around it with the BLP 1085 cfm carb.
It's a 1969 Pontiac Grand Prix Governor I am using now.
Code PR 400 turbo, 428 390 Hp 480 ft/lbs that Original car it came from.
Used the stock outer weights and stock inner return springs.
#5 & #6 inner weights from B&M.
Drives normal light foot on the gas.
Just a Bullet now dead stop to 111-120 mph.
Really have to Concentrate 200%.
It's getting loose Azz tail end like I stated.

No Electric lockdown hooked up.
63 Gp never had a Turbo 400 trans stock.
Turbo 400 came out in 1964 and Cadillac got it exclusively for '64.
1965 Pontiac and Chevrolet finally got the Bullet proof TH400.
4L80E Grumpy Loves based from TH400 with Overdrive, many near all internal hard parts interchange.
 
The Lighting drilled punched outer weights in Governors shown are Chevrolet issue.
Chevy Trucks had them stock.
A bit high Performance there.
I tried but light foot throttle driving it was hunting around low speeds what gear to be in.
Chevy SB wants another 500-600 rpms Revs to get into Torque band Vs 455 Poncho.
How Chevy GM set them up ideal for.
 
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