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Excellent info let me throw a couple of questions out there.

I've just recently swapped in a big block into my 66. Behind it is a 700r4.

The 700r4 used to be behind a very strong 383, (very nearly 500hp) I got it from my friend Jeff smith (car craft mag) We've got it dialed in pretty nice.

My question(s) is this. As I am not familiar with the 700r4 behind this engine I don't know precisely how strong the shifts should feel, to me the 2-3 shift feels soft, the 1-2 shift seems ok to me, its not strong but I can feel it. The 3-4 shift is good as the convertor is wired to lock up as soon as it goes into 4.

I think, but am not sure, that I am getting a little bit of flare in the 2-3 shift but only when slowly accelerating. When i get on it the tire (still need posi :) ) spins all the way into 4th gear with no noticeable flare at all. The shift points seem correct to me based on what I've read. I am thinking that a shift kit is in my future and I should probably also do the corvette servo swap (assuming it hasn't been done already)

This big block makes a lot of torque never falls below 500 ft/lb above 3000 rpm and 527 hp peak so I am a little concerned about durability since we aren't really sure what's in this tranny. I don't race so it isn't going to be abused apart from the occasional burnout.

If you have p/n for the servos and shift kit as well as a source I would be really appreciative.

Thanks and happy holidays/new year.
 

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Good Morning Eric
I don't have your torque or burn my tires smaller. Yet I have similar experiences with the 700R4.
I feel some of our firmer 1 - 2 shifting be coming from the wider range from 1st to 2nd than most trans. The 2 - 3 shift is closer to the older trans.
Gear|.TH7004R|..TH350.|..TH400
1st | 3.06:1 | 2.52:1 | 2.48:1

2nd | 1.63:1 | 1:52:1 | 1.48:1
3rd | 1.00:1 | 1:00:1 | 1.00:1
4th | 0.70:1

This short article from BowTie OverDrives describes why my 3.08 rear end feels like a 3.73 when using the low gear of the 700R4. The difference is not there as much for the 2nd and third gear.
http://700r4.com/faq/ratiocmp.shtml
 

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Eric says.
"I think, but am not sure, that I am getting a little bit of flare in the 2-3 shift but only when slowly accelerating. When i get on it the tire (still need posi :smile: ) spins all the way into 4th gear with no noticeable flare at all. The shift points seem correct to me based on what I've read. I am thinking that a shift kit is in my future and I should probably also do the corvette servo swap (assuming it hasn't been done already)"

My 2-3 and 3-4 are very soft. I too go into lockup right after entering 4th.

TCI offers (OK - Marketing says) they have servo kits that offer better performance. See the Heavy Duty Servo kit descriptions and their reference to flare.
http://www.jegs.com/p/TCI/TCI-Servo-Kit/755466/10002/-1
http://www.tciauto.com/tc/700-r4-4l60e-2nd-gear-servo-kithtml/

Is anyone running the TCI servo kits?
 
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