Quest for 7's in the 1/8

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318willrun

318willrun

Utube channel 318willrun
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Heading into winter, strips are closed, so looking forward ..... As we continue to whittle at the ET with Drag Truck (not really a drag truck, it's a 1980 D150 long bed pulled from a farmers field).

It's ran a 8.27. The transmission is a 100% stone stock 727 from a '85 D150 we got for free. Works good but slightly sluggish on the shifts. If we Rebuilt it with a manual VB, be enough to go 7.99 ?? Thought strongly about a built 904, but drive shafts are expensive.

Thoughts ?? Thanks
 
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Unless you are slipping, a overhaul probably won't get you there. What rear gear are you running and what trap rpm are you turning?
 
toolmanmike said:
Unless you are slipping, a overhaul probably won't get you there. What rear gear are you running and what trap rpm are you turning?
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4.30, RPM's unknown as it's time out was 1/8 only that day. I won't run out of RPM's in the 1/4. I know a fresh transmission with a MV would offer something, just not sure if it would be enough.
 
Mtrhead said:
NOS power shot 125hp plate system
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I think that would move the bar more than 2.8 tenths.. LOL. There are 110 ways to drop the ET to 7.99... I'm wondering if the transmission work listed above is enough ?
 
3.55 or lower gear in that heavy truck.
I had a 78 D150, 3.55, 904, 14 inch rear wheels 8 1/2 inches wide with soft cheater track radials, a 360 with headers , J heads cleaned up making near 345 to 360 hp. 7. 21 fastest pass using a traction compound off a foot brake, just a 2400 stall out of a 4x4 truck. But remember I was pulling a .420's lite... truck was just to heavy.
Be careful with twist, broken shock mount and twisted frame near steering box.

Now that trans and 360 in in my 66 early A Plymouth sedan .
Lift the front as much as you can and lower the back to help with weight transfer.

Just an old Arkansas Hillbilly enjoying our 1/8 mile track for the last 40 year.. :lol:
 
I put a transgo 3 shift kit in a 904 which as you know is the same exact valve body and it worked like a manual shift. It's the same as the transgo two it just acts as if it has a manual valve body. You will have to shift down and shift up and start from low or it will just start wherever you put it. Also the nice part is you go ahead and wire the pressure lever wide open eliminating the need for all the kickdown linkage... To me it shifts pretty much the same as a transgo two just manually...
I just rebuilt the transmission in my power wagon and it was $113 for the rebuild kit and I want to say $90 for the shift kit... I was told the transmission ran and shifted just fine but there was a lot of worn out clutches in there..
Since it's winter and you can pull it out and have it on your bench it's really quite the easy job to change all that stuff out without getting too invasive.. you don't have to change all the bushings just the front and rear seals the lip seals and the clutches..
 
j par said:
I put a transgo 3 shift kit in a 904 which as you know is the same exact valve body and it worked like a manual shift. It's the same as the transgo two it just acts as if it has a manual valve body. You will have to shift down and shift up and start from low or it will just start wherever you put it. Also the nice part is you go ahead and wire the pressure lever wide open eliminating the need for all the kickdown linkage... To me it shifts pretty much the same as a transgo two just manually...
I just rebuilt the transmission in my power wagon and it was $113 for the rebuild kit and I want to say $90 for the shift kit... I was told the transmission ran and shifted just fine but there was a lot of worn out clutches in there..
Since it's winter and you can pull it out and have it on your bench it's really quite the easy job to change all that stuff out without getting too invasive.. you don't have to change all the bushings just the front and rear seals the lip seals and the clutches..
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I'm thinking for sure this transmission will have worn clutches as well, at the very least. I just wonder if rebuilt and quicker shifts would move it to a 7.99 ??? I mean, the transmission does work decent, but it's not fresh !
 
318willrun said:
I'm thinking for sure this transmission will have worn clutches as well, at the very least. I just wonder if rebuilt and quicker shifts would move it to a 7.99 ??? I mean, the transmission does work decent, but it's not fresh !
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First off it wouldn't hurt! LOL and second you don't want to find out how bad the clutches are oh let's say a third of the way through next summer?...
Actually if you just did the transgo two shift kit it gives a on command option which of course I put in line that you can put it in any gear at any time. Meaning if you wreck it down into low at any speed you're going to go into low! LOL also being able to hold the gears out as long as you want. Without the inconvenience of having to shift up and down all the time and again I felt no difference between the two and the three as far as shifting... But you keep drag racing it with old clutches and a super heavy truck and that is shift kit you'll find out how good those clutches are in due time LOL..
The thing is with a fresh transmission you can just cross that off your list...
 
j par said:
First off it wouldn't hurt! LOL and second you don't want to find out how bad the clutches are oh let's say a third of the way through next summer?...
Actually if you just did the transgo two shift kit it gives a on command option which of course I put in line that you can put it in any gear at any time. Meaning if you wreck it down into low at any speed you're going to go into low! LOL also being able to hold the gears out as long as you want. Without the inconvenience of having to shift up and down all the time and again I felt no difference between the two and the three as far as shifting... But you keep drag racing it with old clutches and a super heavy truck and that is shift kit you'll find out how good those clutches are in due time LOL..
The thing is with a fresh transmission you can just cross that off your list...
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Agree. Also, at what time do the seals/gaskets start to leak ?? LOL. But... when I pull it, I want to find 2.8 tenths in it !!!
:thumbsup:
 
318willrun said:
Agree. Also, at what time do the seals/gaskets start to leak ?? LOL. But... when I pull it, I want to find 2.8 tenths in it !!!
:thumbsup:
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LOL I don't know about 2.8 tents... But whatever you do to the engine to get the extra power for the hat at least the transmission will handle it...
 
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easy...
 
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All my highly technical tools... LOL that and advice... The piece of c-shaped metal at the top of the picture is for a 904 and the little c shape piece of metal and the flat piece of metal are for the 727. This is just to get the spring tension off of one of the drums. And the toothpick is for the lip seals and don't forget your extra large jar of generic Vaseline you'll need it LOL...
 
318willrun said:
And... I'm not throwing out using a 904. I will get 3 tenths for sure if I go to a built 904 vs a tired 727.
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If you go to the 904 you'll need a longer drive line in a different slip yoke..
Personally I would stay with the 727 in a truck...
 
Anyways if you do decide to go for rebuilding the transmission I have a few tricks and tips that I've learned...
 
j par said:
If you go to the 904 you'll need a longer drive line in a different slip yoke..
Personally I would stay with the 727 in a truck...
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yep and yep... however, 904's are brutally tough when built right. I have a friend that uses one in his full size Dodge truck and has gone low 11's, and transmissions are not an issue. A lot of drag cars out there going really fast (single digits) with 904's. I'm not worried about breaking it, I'm just looking at the cost of driveshaft and yoke.
 
318willrun said:
yep and yep... however, 904's are brutally tough when built right. I have a friend that uses one in his full size Dodge truck and has gone low 11's, and transmissions are not an issue. A lot of drag cars out there going really fast (single digits) with 904's. I'm not worried about breaking it, I'm just looking at the cost of driveshaft and yoke.
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"Built right"=$$$... I know the 727 is larger inside all around.... If I was drag racing my Duster and Lord forbid wanted an automatic I would do the 904... Is your truck the same weight as your friend's truck?..
 
j par said:
"Built right"=$$$... I know the 727 is larger inside all around.... If I was drag racing my Duster and Lord forbid wanted an automatic I would do the 904... Is your truck the same weight as your friend's truck?..
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He has two trucks, one is a little lighter and one is a little heavier. Both run 904's.
 
I think it kinda depends on how slow the shifts are now, and how soft and overlapping the shifts are. Are you manually shifting, or do the shifts come when the trans wants?
Brutal truth, I don't see three tenths in a trans rebuild unless it was slipping pretty bad in gear. I doubt better gear changes will help that much.
 
33IMP said:
I think it kinda depends on how slow the shifts are now, and how soft and overlapping the shifts are. Are you manually shifting, or do the shifts come when the trans wants?
Brutal truth, I don't see three tenths in a trans rebuild unless it was slipping pretty bad in gear. I doubt better gear changes will help that much.
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I manually shift it at 5600 rpm's right now. I didn't get enough passes to see if it liked more rpms. But, 5600 sounded good by ear, and felt right.
 
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