Can you modify gear sizes/acceleration ratios in a Turbo 400 automatic Transmission?

125

Asked by Sep 30, 2009 at 06:15 PM about the Pontiac Firebird

Question type: Car Customization

Turbo 400 only has three gears and the first gear gets skipped during a 5000 RPM flooring with a 455 engine.

3 Answers

35,665

3rd will still be direct drive so 1st and 2nd need to be sized accordingly. its not like a manual trans with gears. ur best bet would prolly be to go with a 700r4 and fabricate a rear trans mount bc the 700r4 is pretty much the only 4spd auto that isnt electronically controlled so no computer

35,665

n check ur rear end ratio it prolly aint helpin either

12,425

First gear should not skip no matter WHAT GEAR or TRANS you have in it. Sound like you have a trans govenor problem, or kick down linkage problem. If you floor it both mechanism should start you off in first and if I remember correctly the 400's have a govenor overide which actually will shift the car into second with the gear shift still in the first position. I like the 700r4 JOHN as thats what I have in my race car for the lowest 1st gear that GM made Manual OR automatic. However that being said the trans has to be beefed up to accept that kind of power. The only electronics in the R4 is the lock up converter which in my case isnt there anyway :)

Your Answer

Firebird

Looking for a Used Firebird in your area?

CarGurus has 770 nationwide Firebird listings starting at $4,000.

ZIP:

Pontiac Firebird Experts

  • #1
    Samuel Moore
    Reputation
    990
  • #2
    dandyoun
    Reputation
    840
  • #3
    Tom Demyan
    Reputation
    730
View All

Related Models For Sale

Used Chevrolet Camaro
453 Great Deals out of 31,416 listings starting at $1,450
Used Chevrolet Corvette
174 Great Deals out of 17,500 listings starting at $3,000
Used Ford Mustang
596 Great Deals out of 39,173 listings starting at $1,895
Used Pontiac GTO
6 Great Deals out of 445 listings starting at $4,995
Used Dodge Challenger
253 Great Deals out of 25,100 listings starting at $7,750
Used Ford Mustang SVT Cobra
7 Great Deals out of 314 listings starting at $4,795
Used Dodge Charger
466 Great Deals out of 33,553 listings starting at $1,999
Used Pontiac G8
9 Great Deals out of 443 listings starting at $5,400
Used Dodge Viper
265 listings starting at $26,000
Used Chevrolet Silverado 1500
2,653 Great Deals out of 173,970 listings starting at $955
Used Ford F-150
3,207 Great Deals out of 220,486 listings starting at $1,200
Used Nissan GT-R
502 listings starting at $47,995
Used Jeep Wrangler
462 Great Deals out of 19,374 listings starting at $2,500
Used Ford Shelby GT350
5 Great Deals out of 1,626 listings starting at $47,999
Used Porsche 911
121 Great Deals out of 5,148 listings starting at $10,947

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.