727 trans questions ???

Hello, I just picked up a 74 Barracuda with a transplanted 440/727. The trans has been messed with. It's a not a manual or reverse pattern but it shifts into second at 1500 and the prior owner told me it won't shift into third until 9000 if you keep your foot in it. It also has an aftermarket converter with a drainback issue. I'm thinking it's going to need a valve body to fix whatever was done to it but I'm also wondering if the governor was swapped/modified. I have a complete small block 727 with part throttle kickdown from a 73 Roadrunner that I can rob for parts and a TF2 kit from transgo. Any thoughts? I don't know what year trans is in the car, the motor is a 60s forged crank 440. Thanks

9000, really?

That's what he told me, I wasn't going to try it myself. I've been reading and it may be a throttle pressure issue caused by using a kit like the TF2 that I have. It may be easier to just swap to a stock valve body instead of playing detective.

Agreed on starting with a standard valve body. If you have a stock valve body and standard governor most times you are good enough.
If you want to firm up the shifts, etc. then go to a kit.

But at this point make you have to wonder if the previous owner/builder didn’t dink with servo springs, front clutch tweaks.

You won’t know until you start with a baseline valve body. I would do one thing at time, governor next if needed.
As for drainback unless someone drilled the valve body then you likely have excessive pump clearance.
Sonnax makes a regulator valve to help with this but try starting it in neutral - that will charge the converter.


Keep us posted on your progress.

At the same throttle setting? A combination of governor mods and TP linkage adjustment can delay the WOT 2-3 upshift to extremes but it would also delay the 1-2 upshift.

I had this same problem years ago, it would only get to 40 psi line pressure, so the 1-2 shift was great, 2-3 not so good, let off the trottle & it would shift,,, nail it & it would go back to 2nd gear,it had a governor problem as it turned out

Hopefully it’s something simple, but the drain back issue makes me think the valve body was fooled with. My old Challenger would get ‘morning sickness’ but it was a slow seep. I’ll report back in a few weeks.

I don’t know what kind of goofy shift kit is in this thing but it’s in second by 15 mph. It’ll ride out second forever if you let it. If you back off to very light throttle it slams into third at 45 mph. Hard. The shift points are completely wrong for the torque curve of the motor and the rear end. The car should be flying but it’s just dogging along in second forever - never gets to build any power and wants to run out well in third which it never sees.

I’m not sure if the converter is going to be an issue or not, I was told it’s a 2800 stall and it feels loose but I’ve run a factory Hemi converter before and it was fine. I’ll have to see how it responds to a stock valve body. In either case, I’ll get it running right. Feels good to be back in a big block e-body. 😎

Thanks

Once again, are you saying it upshifts 1-2 at 15 mph with WOT or light throttle? If light throttle, try completely disconnecting the TP linkage at the trans lever and push the lever full forward. If it shifts early with the linkage disconnected the problem is in the linkage setup.

With ANY throttle. The pinion snubber is getting a workout lol

Your statements are contradictory.
Early 1-2 shift them late and harsh 2-3. Something is jacked up.

You can try what JK asks. That would be another’s piece of info.

But I go back to installing a known stock valve body since obviously someone has dinked with this one.

Well that's what it's doing, and doing reliably so contradictory or not it's currently reality. I'll post a pic of the linkage at the carb when I get a minute. I want to test that first but I need a second set of eyes or hands. I agree it'll probably end up needing the valve body in the end but doing things in the right order may save work later.

Sorry, let me clarify “contradictory”.

Upshift at 15 is sort of early depending on axle ratio. Light TP setting or fast rate governor.
Then not shifting until 45 is late. High TP setting or slow rate governor.


So that being said, if you try the TP disconnect mentioned and it shifts early for both shifts then the linkage is likely your issue.
If it still shifts late on the 2-3 hen you likely have a vb issue.

Gotcha. I was told the rear has 3.91s, haven’t verified yet. That’s also assuming the speedo is correct but I doubt it’s off by much.

Here’s the linkage setup. A little Mickey Mouse but doesn’t seem awful. Will get a better idea when I can look at the travel on the trans end.

Get the mopar adapter from holley and Put proper throttle pressure linkage on it. What you have there is definitely at least part of the problem. Hope you haven't hurt the trans.

Linkage setup? There is no linkage only a cable.

They did at least use the actual lokar mounting bracket off the back of the carb base. If the trans is hurt there’s not much I can do about it at this point. There might be about 1000 miles on it with that ‘arrangement.’

My trans guy says those Lokar cable setups are far from plug and play. They can be made to function correctly but it takes some doing.

That being said, if it won't shift out of second at WOT without lifting, there's something wrong internally. The governor should force the upshift regardless.

What RPM are you pulling it to? Even if it had a Hemi governor in it, it should shift WFO by 5500ish.

Kevin

I’m not going to push it hard enough to find out. My only saving grace may be that the pressure is jacked so high that damage has been kept to a minimum. If I’m satisfied that the kickdown is functioning I’ll move on to the valve body. Not surprisingly there are a few other issues with the car that also need to be sorted out before it hits the pavement again. Nothing I can’t handle but it all takes time.

that lokar cable setup is your problem, and someone more than likely jacked up the line pressure to "sorta" make it work.
remove that garbage and toss it in the trash. you are not going to get it to work unless you plan on spending LOTS of time fiddling with it.
get a factory setup plus whatever carb adapter is needed for the factory linkage to work. then check and adjust your line pressure as needed.
just my experience removing over a dozen of those junk lokar setups.
if a cable is absolutely needed, try a boushillion kit. it is WAY better than lokar will ever be,
your mileage will vary.