This will be long winded. All mods in sig. This car has had the flare since I bought it two years ago. I ported the heads and then had frost dyno tune the car. Car would shift fine on cold transmission. As it warmed up it got worse, but was always unpredictable as to when it would do it. Car has always shifted fine other than wot 2-3 shift. Since it seemed fine cold, I added a second trans cooler. I have a tube and fin and a plate style both mounted to the front of the ac condenser. I never see temps over 150 even at the track. This helped a little but was still there. Next, I added a Transgo HD2 kit. I followed the instructions and drilled all holes to .093 and the 3rd apply to .125(per research I did). I reused my spacer plate(remember this) and did not install the return springs in the kit. I also had my converter gone through and re stalled by PTC. The trans shifted great for about a week, the 2-3 shift was very fast. Then it began the same thing again. The fluid in the trans was not that bad when I did the shift kit so I did not thing it was burning the clutches. At this point I netted my best ETs in my sig. However, I peddled the 2-3 shift on nitrous to avoid the flare. So this winter, I did some more upgrades and bolt-ons and the flare was still there. I have an aftermarket autometer tach and by its read out when the car shifts properly it shifts at 6100-6200 per the tach. It would flare to about 6400-6500. If it flared to the 6500 mark it would hit the limiter. So I called Steve (Frost) and spoke with him and asked if it could possibly be the mph could be set too high in the tune. He pulled my file and assured it should be fine. He also informed me that my tune was set to shift at 6500 and rev limiter at 6800. This did not agree with my tach and we did discuss that the ecu read out for the stock tach is normally low by 3-400 rpm. This is where my autometer and nos mini is tied in. I have not tried going directly to a negative side of a coil, yet. However, based on my recently tested valve spring and spring pressures he agreed to raise my limiter to 7100. I had to try something, Steve did not think this would fix it. He said the 300 rpm spread that was in it should be more than enough time for the shift to occur. So we raised the rev limiter and it still did it, but now, I was able to get off the gas before it hit the limiter. I hate hitting the limiter and I figured if the trans was going it was going, and I would rather be able to stay of the limiter. So what I have always noticed(and other people have described the same problem) was that on a dig where the car did not get good traction and short shifted the 1-2 shift and second gear had to pull from about 4000 all the way to 6100ish per my tach is when it normally did the flare. However, if I was going 60 mph and floored it and it downshifted to 2nd it would make a nice shift to 3rd gear, even if it had just flared on a dig. At the track where I get good traction on motor when it made a nice pull all the way through 1st gear and 2nd it would shift fine, but it didn't have to make that loooong pull through second so it shifts fine. So I got to thinking what's left. I have overfilled the trans like everybody else has tried and it does help a little, however if you overfill it too much it churns the fluid and puts air in the fluid, which is just as bad as being low on fluid. I knew back when I did the shift kit I reused the separator plate and the holes for the check ***** were pretty worn but I was in a hurry to get it back together. So I decided to go pick up some of the .250 torlon ford check ***** and the transgo separator plate which is a little thicker than stock. I drilled this plate exactly like the stock one above. When I pulled out the separator plate this time the holes for the check ***** were even worse and you could tell fluid was leaking past them. Put it together with the new stuff and it shifts good but still has the damn flare on a long pull in second gear at high rpms. What's left? I finally decided it had to be sucking the pan dry(stock 4l60e is only rated to 6000rpm). So I ordered dorman part number: 265-811 which is the same as the deep truck pan. Stock pan is about 2" deep. This pan is about 3 1/8" deep. It does have drain plug on the bottom which I cut the head off the bolt re-installed the threaded portion and welded it shut. My car is pretty low and I think stock height would be fine to leave it as is. I also have 3 bolt flanges on my header to y-pipe and the pan welded up is about 1/2" above the bottom of my headers(pacesetters). I then welded the fitting in the front left corner for the 1/8" npt trans temp sensor(I can drain fluid from here). I used driveworks filter DWFK373. I was able to add an additional 2 qts with this pan. I went out and beat on it, got the temp to 150 degrees, and came back to check fluid level and it was 1/4" above the full line(same as stock pan with extra 1/2 quart). While I was out I immediately noticed it was taking longer than normal to get heat in it, again, 2 huge coolers and now 2 extra qts of fluid. Good news is I must have done 30-40 digs, long 2nd gear pulls, 60 mph downshifts. One after another, and it made the shift every single time, not the first flare of any degree. I mean every shift was quick and on the money. I'll keep updating this I drive it more and make it to the track. Hopefully this can help some people. I am so relieved as long as this is the fix.

 

interesting find-the force of accel. drives the fluid back in the pan, so I guess if you were getting close to sucking the pan dry some would be pushed back away from the filter
I wonder if on the orig setup maybe there wasn't enough room bet the filter pickup area and the bottom of the pan
some of those filters sure don't look like they have much of a pickup area
I am guessing the trans dipstick is the correct one with the correct fill level

 

Yes it is correct, when I drained it the pan I used is marked and exactly 5 qts came out. All the filters I have seen have the same amount of pick up space and sit about 1/4" off the floor.

I wasn't surprised between the sloshing back of the fluid and spinning the trans at higher rpm than designed. Plus however much more is pumped from the .500 boost valve I put in the pump with the HD2 kit. When I drag raced motorcycles we used oil pickups that swung back and forth in the oil to follow the sloshing of the oil. I think the trans is more prone to suck air because the opening in the trans filter is quite large and although it's close to the floor of the pan when the fluid sloshed back it doesn't cover the entire filter inlet and suck air.

 

watching this one.

 

Had the car out earlier. Made every shift again beating on it.

 

Still hitting every shift, and the weather here was a little warmer today as well, tranny temps peaked 150 today.

 

Many members here have recommended overfilling the trans by 1/2 quart to reduce flares and slippage. Nearly everyone here has modded their car to accelerate much faster than stock.
Better yet, many posts recommend the truck pan (also has a drain plug) or other +1 quart pan. Personally I have a +1 quart aluminum deep pan found on ebay for $60.

Thank you for the detailed description proving you correctly tried all the "normal" things to reduce flair and that the additional fluid capacity was the solution.

Very informative!

 

very informative and thanks for sharing. i'll have to def try this if i get the 2-3 flare issue. p/n 265-811 correct?

 

Mine doesn't like to be overfilled or it will puke fluid from the vent on hard WOT blasts.

So I would recommend to those who wish to try it they do so in small increments. The smell of burning trans fluid after a WOT run is quite unnerving to me haha.

 

i remember when I built my first 80E I had a pressure gauge on it, and it would still be building pressure within a qt or so of fill level, so they do like their full fill

 

Truck pan and truck filter will give you an extra inch
of pickup submersion, if you want.

 

Cliffs please? lol

 

Thanks for the info.
My car also has a flare at times. I will try the truck pan.

 

Not going to lie, I haven't even read the OP's wall of text (paragraphs please?) but I will also mention even with the truck pan and filter mine was having some flare issues which were cured by installing this:

http://www.sonnax.com/parts/2464

 

Did you have to mod the 3/4 exhaust hole on the trans pan rail? I bought one of these pans and it covers up the hole on the pan rail.

 

I didn't change anything on the pan.

 

Still shifting perfect car ran 11.41@119 last week and 11.50@120 this week