hi all
would like to hear real world info about gears used in their g bodys.buiding an 87 grand prix with a 471 455 pontiac fuel injected engine.the tci is near $10k.plan to use a ford 9in maybe with a 3.00 or 3.25 ratio.
thanks
Using the latest developments in drivetrain technology, TCI® has developed an innovative automatic transmission for Pro Touring, street and all-out race vehicles. Designed for Pontiac applications, this 4L80E-based TCI® 6x Six-Speed Automatic Transmission is a fully programmable transmission that gives you six forward gears (2.97, 2.23, 1.57, 1.18, 1.00, 0.75) for quicker acceleration and increased fuel economy at cruising speeds. Capable of handling up to 850 horsepower, this versatile transmission from TCI® features a compact design, allowing it to work in a variety of performance applications.
from another thread
6X is a close ratio automatic transmission. 2nd - 5th gear is similar to manual M20 close ratio tranmission. RPM retension between shifts is unmatched by any A4 automatic. Notice the drive ratio in each gear with 3.55 rear gear and what rear gear a T56 6 sp manual car would need to match the 6X ratio wise in 4th gear as well as come close in 2nd & 3rd. T56's 1st gear is it's only gear with better mechanical advantage than 6X, but it may be a little to much advantage as RPM lost between 1st to 2nd gear is huge even with perfect shift, taking engine out of it's power band. My 64 still has a 3.54 1:1 5th gear for a little more top end.
6X has average lost of 1600 RPM between shifts. Shift at 6500 RPM and engine RPM only falls back to 4900 +/- 100 RPM. Less converter stall needed, that may hurt 60" time when drag racing at strip, but sure doesn't hurt street fun factor...LOL
TCI 6X
2.97
2.23 -- 76.10% (high) RPM Retention -- 23.90% RPM DROP
1.57 -- 70.40% (high) RPM Retention -- 29.60% RPM DROP
1.18 -- 75.16% (high) RPM Retention -- 24.84% RPM DROP
1.00 -- 84.75% (high) RPM Retention -- 15.25% RPM DROP
0.75 -- 75.00% (high) RPM Retention -- 25.00% RPM DROP
TCI 6X, 3.55 rear gear
Car only has 360 Peak HP at rear wheels, Converter is stalled at 2800 RPM so not much more flash than stock. You can hear engine rpm drop very few RPM between 1st/2nd and 3rd/4th shifts. When car shifted into 5th near top of the hill it was doing 132 MPH per tuners data logger. Use of Old School mechanical advatage to help make up for not having a lot of HP.
seems relitive to me
would like to hear real world info about gears used in their g bodys.buiding an 87 grand prix with a 471 455 pontiac fuel injected engine.the tci is near $10k.plan to use a ford 9in maybe with a 3.00 or 3.25 ratio.
thanks
Using the latest developments in drivetrain technology, TCI® has developed an innovative automatic transmission for Pro Touring, street and all-out race vehicles. Designed for Pontiac applications, this 4L80E-based TCI® 6x Six-Speed Automatic Transmission is a fully programmable transmission that gives you six forward gears (2.97, 2.23, 1.57, 1.18, 1.00, 0.75) for quicker acceleration and increased fuel economy at cruising speeds. Capable of handling up to 850 horsepower, this versatile transmission from TCI® features a compact design, allowing it to work in a variety of performance applications.
from another thread
6X is a close ratio automatic transmission. 2nd - 5th gear is similar to manual M20 close ratio tranmission. RPM retension between shifts is unmatched by any A4 automatic. Notice the drive ratio in each gear with 3.55 rear gear and what rear gear a T56 6 sp manual car would need to match the 6X ratio wise in 4th gear as well as come close in 2nd & 3rd. T56's 1st gear is it's only gear with better mechanical advantage than 6X, but it may be a little to much advantage as RPM lost between 1st to 2nd gear is huge even with perfect shift, taking engine out of it's power band. My 64 still has a 3.54 1:1 5th gear for a little more top end.
6X has average lost of 1600 RPM between shifts. Shift at 6500 RPM and engine RPM only falls back to 4900 +/- 100 RPM. Less converter stall needed, that may hurt 60" time when drag racing at strip, but sure doesn't hurt street fun factor...LOL
TCI 6X
2.97
2.23 -- 76.10% (high) RPM Retention -- 23.90% RPM DROP
1.57 -- 70.40% (high) RPM Retention -- 29.60% RPM DROP
1.18 -- 75.16% (high) RPM Retention -- 24.84% RPM DROP
1.00 -- 84.75% (high) RPM Retention -- 15.25% RPM DROP
0.75 -- 75.00% (high) RPM Retention -- 25.00% RPM DROP
TCI 6X, 3.55 rear gear
1st gear | 2.97 | 3.55 | 10.54 | |
2nd gear | 2.23 | 3.55 | 7.92 | |
3rd gear | 1.57 | 3.55 | 5.57 | |
4th gear | 1.18 | 3.55 | 4.19 | |
5th gear | 1.00 | 3.55 | 3.55 | |
6th gear | 0.75 | 3.55 | 2.66 |
T56 man | |||||
1st gear | 2.66 | 4.19 | 11.15 | 0.60 | |
2nd gear | 1.78 | 4.19 | 7.46 | -0.46 | |
3rd gear | 1.30 | 4.19 | 5.45 | -0.13 | |
4th gear | 1.00 | 4.19 | 4.19 | 0.00 | |
5th gear | 0.74 | 4.19 | 3.10 | -0.45 | |
6th gear | 0.50 | 4.19 | 2.10 | -0.57 |
seems relitive to me
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