hybrid 727

Posted By: emarine01

hybrid 727 - 09/15/09 06:17 PM

Is it possible to build a 904 in a 727 case? or use the best parts from a 904 in a 727, this is for a 4x4 application and I don't want to shift any weight forward switching from a 727 to a 904 and I cant move the engine any further back, are there any options here

Posted By: Garceau

Re: hybrid 727 - 09/15/09 08:08 PM

Yes there is....but not sure how. I thought I remember people putting 904 stuff into the 727 because the 904 is faster do to less rotating mass.

Posted By: Hemiroid

Re: hybrid 727 - 09/15/09 08:11 PM

It's been done forever. Stockers and SSers use them today. Talk to Smith at Pro-Trans. Not sure one would live in a 4x4 though

Posted By: emarine01

Re: hybrid 727 - 09/15/09 08:50 PM

Cool, I wasn't sure if it was a totally retarded question

If I can put most of a 904 in a 727 will it still free up some power & weight?

Posted By: JohnRR

Re: hybrid 727 - 09/16/09 01:06 AM

Quote:

Cool, I wasn't sure if it was a totally retarded question If I can put most of a 904 in a 727 will it still free up some power & weight?

Yes it will but it's NOT CHEAP , and you'll have to go thru it often .

Posted By: emarine01

Re: hybrid 727 - 09/16/09 01:14 PM

Well I don't know what sounds worse the not cheep in caps or go thru it often, One thing about my porkflite it has been very reliable at the power levels we run, the fact that a 904 frees up so much power is very appealing, is there a way to free up power in a 727 that would be more cost effective & stronger? We have become good at trashing drive line parts in the last few years, the cost of a 904 does not really bother me that much if it can make a season with out failure but the thought of building several of the them in a year wont cut it

Posted By: JohnRR

Re: hybrid 727 - 09/16/09 01:45 PM

Quote:

Well I don't know what sounds worse the not cheep in caps or go thru it often, One thing about my porkflite it has been very reliable at the power levels we run, the fact that a 904 frees up so much power is very appealing, is there a way to free up power in a 727 that would be more cost effective & stronger? We have become good at trashing drive line parts in the last few years, the cost of a 904 does not really bother me that much if it can make a season with out failure but the thought of building several of the them in a year wont cut it

Put lightweight parts in the 727 and fully rollerize it ? You'll have to keep up with band adjustments and fluid changes if you get an alum front drum, don't use a kelvar band on it, soild red lined, initial cost will be cheaper than one of those 727 with 904 internals, which I think cost 5k and/or more ...

Posted By: S/ST 3040

Re: hybrid 727 - 09/16/09 02:07 PM

I thought you were going to start drag racing?

Posted By: emarine01

Re: hybrid 727 - 09/16/09 02:39 PM

I cant make up my mind, we are so close to a light class record on dots that If I quit before I give my best shot , well you know what I mean, the record was set 9 years ago and I am 3/100s off, only problem is that I have slowed some this summer, truck never liked the heat, I am still huntin for a A body but it seems that I am more picky than I thought,the last time I drag raced was at englishtown on a 900 kawi 30 years ago so I will be startin from scratch, some of it is the economy also, dont want to get in too deep with 3 kids and the fact that we own horses< giant waste of major bucks> but the wife & kids like them, looks like this winter we will regroup and pick a direction

Posted By: John_Kunkel

Re: hybrid 727 - 09/16/09 09:50 PM

The stock class racers put 904 guts in the 727 case because the class rules specify the original case must be used; for non-stock racing, mating the 904 to a big block can be done with an Ultrabell housing. Lots cheaper than adapting the 904 guts.

Posted By: emarine01

Re: hybrid 727 - 09/16/09 11:46 PM

It looks like any investment into a good trans for a 4x4 will carry over to a drag car with a change in output shaft, How much power does a roller 727 free up?

Posted By: LA360

Re: hybrid 727 - 09/17/09 01:13 AM

You'll spend around $6K on a Pro Flite (727 with modded 904 internals). They can be ordered with one of the 20 or so gear ratios available for them. Don't think it would hold up too long in a 4x4, as they are a high maintenance item in a Comp car.
Speak to someone like John Cope or Rick Allison about your options
AL....

Posted By: 70AARcuda

Re: hybrid 727 - 09/17/09 03:03 AM

I know a 68 340 barracuda that run F/SA in nhra and he uses a 904......the trans was bought from protrans, I asked about the 727, he said they could now run 904s.

that trans with the 904 liteweight parts and low drag was around 6k.

Posted By: S/ST 3040

Re: hybrid 727 - 09/17/09 03:35 AM

2009 NHRA Rule Book (pg. 107) Stock

TRANSMISSION, Automatic
Any model transmission (Must be same make as car) having same number
of forward speeds. (OD gear not required) and reverse permitted.
Transmission case must be OEM from a standard automotive application
as found in the Official NHRA Stock Car Classification Guide.
NHRA-accepted adapter plates permitted............

I looked up that Classification Guide and didn't find anything that specified applicable transmissions.

Posted By: emarine01

Re: hybrid 727 - 09/17/09 01:42 PM

Well 6k is not in the trans budget this year, I was hopin to come in under 2k so time to go another way, In mud racing we don't torque up on parts like drag racing,just not enough bite on the hit, so a 904 my live longer in this application, does anyone know how much shorter a 904 case is from the bell to the back of the case where the sprag is? I may be able to move the fire wall back where the dist is a few inches and set the engine further back, this is a good option for me as we are way to front heavy now and it would save me from making up 2 new drive shafts and a transfer case mount

Posted By: S/ST 3040

Re: hybrid 727 - 09/17/09 01:57 PM

I can't give you the difference, since I don't have any 727s handy
but, from the mating surface of the bell housing to where the tailshaft
housing bolts on, is 15.875" on a 904.

Transmission mount is in the same location as 727 but, OAL is 3.9" shorter.

Posted By: emarine01

Re: hybrid 727 - 09/17/09 02:11 PM

Thankx Vic, my porkflite is 17" I will have to find a adapter housing from a 904 to the trans case and measure there also, I am assuming that the tail shaft housing has a different bolt pattern?

Posted By: S/ST 3040

Re: hybrid 727 - 09/17/09 02:16 PM

Most likely.....I think the KD levers, speedometer assemblies, valve bodies
and filters are the only interchangable pieces between them.

Posted By: emarine01

Re: hybrid 727 - 09/17/09 02:25 PM

Well at least I have a couple of spare filters to offset the cost some

I picked up 3 727 cores so I can dissect them and start to figure out whats goin on, Looks like some 904s are in order, I will post on the truck form and see if I can learn some more on the output shaft side for 4x4s

Posted By: Anonymous

Post deleted by Defbob - 09/17/09 02:32 PM

Posted By: emarine01

Re: hybrid 727 - 09/17/09 02:45 PM

If I were to go that far it would be a glide, I have been seeing a lot of 400 failures on the big inch stuff in the last couple of years, seems like most of the big power rigs run glides now