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Discussion Starter #1
Mostly stock hard parts in my 80E. Recently freshened and added a Jake's D1 Brake (which works great by the way).
3100 lb car (with driver) 4500 stall, 3.89 gears, 32" tall rear slicks.
I've always thought this trans shifted a bit soft (the brake firmed it up a bit but still a bit soft).
Playing around with the Wallace Racing calculators where you put in your MPH or your ET and it gives you average / good incremental times. My 60 ft's are off by about .010 and by 330, I'm off by .02. Looking at DesKtop Dragstrip, I've done the 1-2 shift by 60' (or right in the middle of it) and by 330 the 2-3 shift.
Previously, I had a Transgo HD2 kit in it and in those instructions, you could pick a shift firmness level by drilling different sized holes in the separator plate. I went fairly large but never went to the "OFF Road" hole sizing.
Wondering if those hole sizing changes might still be do-able with Jake's D1 brake or would it not work with his system ?
Anybody done it ?
Or any other tips to maybe pick up some shift firmness ?
A typical run would be a 9.10 @ 148 with a 1.37 60' and 3.79 330'.
Trying to dip into the 8's with tuning - not just throwing money at it.:cool:
This is a blown (10 lbs. boost) BBC BTW.
 

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You can definitely drill the holes bigger for firmer shifts but soft shifts aren't a complaint I get with that valve body.

Possibly the converter is loose enough you aren't feeling the shifts?

If you decide to drill the holes, they are the same holes as the TransGo instructions for each gear. I would be conservative with the 1-2 feed hole.
 

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Discussion Starter #3
Thanks Jake.
~4500 stall, if I "pay attention", I can feel the 1-2 shifts and they seem relatively quick but far from "hard". Can't say I've ever really "felt" the 2-3 though.
Data logger on it, 65 - 6700 shifts and you can see on the graph where it drags the engine down about 600 rpm on the shifts.
 

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The 1-2 shift is usually borderline brutal with the D1 transbrake. I reduced feed hole size as much as I dared to keep sprag longevity. We also do not use a checkball to orifice 2-3 oil and accumulators are eliminated so you won't get much more out of 3rd.

I would do a pressure check and be sure you have adequate pressure. It sounds like the converter is covering up the shifts.
 

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Discussion Starter #5
Pressure check today:
P: 200
R: 300
N: 200
4: 195
3: 195
2: 195
1: 195
All #'s at idle, if I bring the rev's up to ~2500, they all climb 10 ~ 15 lbs. and stabilize. Trans oil was < 100 degrees.
 

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Discussion Starter #7
Curious;
Why would they need 300 PSI for reverse ?
I would have expected it in 3rd maybe but R ??
 
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