Moparts
904 or 727
Posted By: w2dak394
904 or 727 - 02/03/10 07:00 PM
wich is faster? more dependant? cheaper? I noticed everyone recomends steel drum for 727 but seen nothing about 904. I will be running this behind 3000Lbs dakota with about 550hp, no trans break. what modifications do i need?
Posted By: WILD BILL
Re: 904 or 727 - 02/03/10 07:19 PM
I have no experience W/ a 904 but I think the 727 is a stronger trans yet it is heavier and takes more hp to run vs a the 904.
Posted By: Mroctober
Re: 904 or 727 - 02/03/10 08:19 PM
904 is going to be faster!! 550 hp no problem
Posted By: 11secdart
Re: 904 or 727 - 02/03/10 08:24 PM
I`ve ran a 904 behind my 550hp small block for years with no problems.
Posted By: hemicop
Re: 904 or 727 - 02/03/10 08:27 PM
Depends what you're looking for & how much HP you're making. IMO a 727 is the only thing for a big-block, but awith a small-block, moderate HP, why carry the extra weight & draw the HP to drive it? You need to be a little more specific what you're looking to do.
Posted By: Otherlane
Re: 904 or 727 - 02/03/10 08:39 PM
if you're like most of us racers we start out running 12 11 10 9 etc do it once and don't look back.727
Posted By: w2dak394
Re: 904 or 727 - 02/03/10 09:36 PM
what modifications are needed to 904 to handle 550hp small block drag race only
Posted By: DavidDean
Re: 904 or 727 - 02/03/10 09:43 PM
I have a 904 with a brake, its a fast and fairly reliable.It has a fair amount of race parts inside.The 727 is about .10-.15 slower behind a SB but more reliable than a mostly stock 904. If I had it to do again I would look serously at a glide though.
Posted By: Otherlane
Re: 904 or 727 - 02/03/10 09:52 PM
I always wanted to know what's faster in a low 9 second car the 904 or 727? give me your opinion
Posted By: dOc !
Re: 904 or 727 - 02/03/10 11:13 PM
Quote:
I always wanted to know what's faster in a low 9 second car the 904 or 727? give me your opinion
ASK any racer in the fast SS classes - especially SS/AA ..... they run a 904 trans behind a Hemi.
Posted By: Otherlane
Re: 904 or 727 - 02/03/10 11:24 PM
ok let get back to the real world I'm not talking $5000 plus trans. they're using a 904 where every hundred thousands count.so how much faster is the 904 vs 727 in a ss/aa hemi car?
Posted By: Locomotion
Re: 904 or 727 - 02/03/10 11:38 PM
In the mid-'70's, Chrysler did some extensive testing between the 727 and 904 transmissions. I believe they were in Stock and/or SS vehicles. If both transmissions are equally prepared and have torque converters that perform the same, the 904 was found to be .10 - .15 faster.
Engine and vehicle weight differences can affect the specific numbers. A heavier, lower HP vehicle would probably see a little more benefit as compared to a lighter, higher HP vehicle.
Posted By: tvt59
Re: 904 or 727 - 02/03/10 11:59 PM
I had a w2 360 with 727 and 8" turbo action converter. Switched to 904 with 8" turbo action converter. Picked up almost a 1/10th in the 1/8 and close to 15/100's in the 1/4. All we did was good clutches and band with the turbo action transbrake valve body. 600-700 passes between rebuild jobs. It never failed on us we just freshened it up every 18-24 months.
Posted By: 70AARcuda
Re: 904 or 727 - 02/04/10 03:59 AM
back somewhere around 1992..i switch from a 727 to 904, both using a turbo action 3800 series converter that flashes to around 4800 rpm...and the 904 was .15 faster and almost 2 mph...
never raced using a 727 again...
Posted By: 512 VALIANT
Re: 904 or 727 - 02/04/10 04:30 AM
Quote:
I have a 904 with a brake, its a fast and fairly reliable.It has a fair amount of race parts inside.The 727 is about .10-.15 slower behind a SB but more reliable than a mostly stock 904. If I had it to do again I would look serously at a glide though.
I know its GM but its strong and its only 1 shift and everyone makes stuff fot it. I run a 727 w/ trans brake and 4500 stall (all Hughes) but when its time to replace it the PG will be looked at, dont if I'll go that route but you have to look. Consistant ET's win races and only 1 shift = consist.
Posted By: dizuster
Re: 904 or 727 - 02/04/10 05:09 AM
A 904 behind a 550HP 3000lb car will last a long time.
It doesn't need a billet drum like a 727 because the smaller diameter has much less inertia, meaning it won't blow up like a 727 will.
Depending on how much RPM you're gonna run, you might want to upgrade the high gear drum release spring, but I've run them up to 7200 on a 340 duster without issue.
Basially just needs a manual valve body, 5.0 lever, good bands, clutches and steels, and a 5 clutch high gear drum (with matching machined pump). That should last a long time.
The other nice thing is that low gear sets are plentiful, and an easy swap.
You just have to be careful swapping different year hard parts around in a 904 because there are some subtle differences that can cause problems...
Posted By: dOc !
Re: 904 or 727 - 02/04/10 05:12 AM
What is the plan these days for bands in the 904 ?
Posted By: dizuster
Re: 904 or 727 - 02/04/10 05:28 AM
There is some debate to use a rigid band or a flex band. The wide flex bands are easier to come by, most of the ridgid stuff is narrower. I don't know if anyone is making the wide ridgid band again or not...
This thread has me thinking of swapping out the stock 727 in our 1972 Dart and swapping in a 904 with some good clutches & steels, shift kit, and a new lever.
Looking to do as much racing with it as possible this year, but it's a street car.
As was already stated, what else is needed to make the 904 hold up forever?
Posted By: Otherlane
Re: 904 or 727 - 02/26/10 03:51 PM
Switching from a 727 to a 904 and picked up a .15 tenths in the 1/4 is good but spending at least $1800 for a 904 trans and converter to be isn't worth it.
Posted By: 360904
Re: 904 or 727 - 02/26/10 03:59 PM
727
Posted By: Otherlane
Re: 904 or 727 - 02/26/10 04:00 PM
To switch from a 727 to a 904 and pick up a .15 is good but how much is the cost to do it? I had the option last year to switch but I didn't just because I had a fresh converter but need a good trans. the 727 was cheaper than a 904 but than I had to buy a $1000 converter was worth it to me.i have a friend that love the 904 but couldn't get a good one built for a low 10 truck so now he running a 727.
I run low 10s with a 904 That I payed no more then 650.00 for all ready to run. Had TA change the hub on the 727 converter 250.00. It's not big dollars to go to a 904. That's cheap for .15
In my case the point is moot, because as of right now we are running a bone stock 1974 T/F-727 in the supercharged Dart.
I know it isn't ideal, and yes I mean bone stock. Pulled the engine/transmission out of a 1974 Dodge truck and put them in the car (1972 Dart).
Then we slapped a 144 B&M supercharger (on top of a slightly modified Holley street Dominator aluminum single 4-bbl. intake manifold), 750 cfm Holley carburetor, my buddy sold us a gently used reproduction 340 camshaft/matching valve spring/roller timing set for $75.00 and we installed the brand new set of Hooker Competition headers that came with the car when we bought it. The car has electronic ignition with a cheap Accell Super Coil.
Anyways my dad wants to race it a few times this coming year so we were looking at building a good transmission for it. He is a transmission rebuilder by trade, but hasn't built much performance stuff.
I just figured if a 904 is "better", that's what will be going in the car.
Either way we have to buy all the parts and a converter for either transmission.
I'm also not a big fan of having to put out money for the billet drum in a 727.
Posted By: Jacob Pitt
Re: 904 or 727 - 02/26/10 06:39 PM
What about going from a mostly stock 904 to a rollerized 727 behind a small block? If the 727 had all aluminum and light weight stuff and the 904 didn't what would be faster?
Posted By: Otherlane
Re: 904 or 727 - 02/26/10 08:20 PM
412 how faster is your car with the 904?
Posted By: 70AARcuda
Re: 904 or 727 - 02/26/10 08:35 PM
paid 300 dollars for turbo action 8 inch converter...rebuild 904 myself for 300 dollars..used valve body from 727 that i already had...
nothing near 1800........
Posted By: B3422W5
Re: 904 or 727 - 02/26/10 08:54 PM
Quote:
What about going from a mostly stock 904 to a rollerized 727 behind a small block? If the 727 had all aluminum and light weight stuff and the 904 didn't what would be faster?
I had my 727 rollerized, aluminum drum, etc, etc, and replaced a stockish 727 with this new trick one on consecutive weekends..i saw exactly zero difference ET wise.
A 904 with most often be about 1.5 tenths quicker than a 727
Posted By: topfueldart
Re: 904 or 727 - 02/26/10 10:13 PM
Quote:
Quote:
What about going from a mostly stock 904 to a rollerized 727 behind a small block? If the 727 had all aluminum and light weight stuff and the 904 didn't what would be faster?
I had my 727 rollerized, aluminum drum, etc, etc, and replaced a stockish 727 with this new trick one on consecutive weekends..i saw exactly zero difference ET wise.
A 904 with most often be about 1.5 tenths quicker than a 727
That would've had me hot! 904 here! Stock rebuild. Flex Band, 4 clutches. Shift kit, 500 horse, 500 torque, mid 11's in a 3550 lb car with no issues.
Posted By: B3422W5
Re: 904 or 727 - 02/26/10 10:15 PM
Quote:
Quote:
Quote:
What about going from a mostly stock 904 to a rollerized 727 behind a small block? If the 727 had all aluminum and light weight stuff and the 904 didn't what would be faster?
I had my 727 rollerized, aluminum drum, etc, etc, and replaced a stockish 727 with this new trick one on consecutive weekends..i saw exactly zero difference ET wise.
A 904 with most often be about 1.5 tenths quicker than a 727
That would've had me hot! 904 here! Stock rebuild. Flex Band, 4 clutches. Shift kit, 500 horse, 500 torque, mid 11's in a 3550 lb car with no issues.
Your right, i expected to see SOMETHING, but after reading many posts on here over the years, other guys who did the same thing havent seen anything either.
that said, the reliability has been super
Quote:
904 here! Stock rebuild. Flex Band, 4 clutches. Shift kit, 500 horse, 500 torque, mid 11's in a 3550 lb car with no issues.
That's awesome!
Posted By: Otherlane
Re: 904 or 727 - 02/26/10 11:06 PM
AARcuda. first thing I was talking about new stuff and everyone like u cant rebuild trans or having parts laying around.in my case for me to switch to a 904 was a lot of money.the 904 race trans was $2300 plus another $1000 converter.$3300 for .15 NOPE. or 2100 for a race 727 and I had a converter. But I got a race trans for $1800. To me I would rather put a glass bumper on my car for $150 and pick up a tenth and have a worry free 727.But my car should run low low 9s too
At 3280 W/D it's been 10.07 @ 132 nothing fancy.
It should go 9.90s this year with no changes to the trans.
Al
Posted By: w2dak394
Re: 904 or 727 - 04/01/10 04:05 PM
what years were the 904 non lock in production? can anyone recommend a builder close to MS?