How strong is a 727

[2059]

stick with the 727 for the bolt up. allot less hassle and unless your building something exotic it's not worth it. Not an auto guy now but back in the day rebuilt a couple 727's, and with the right parts they can handle damn near anything you'll throw at them... kind of like unobtainium... the guys at A&A can help with parts or full piece. but as stated, strong=$ initially; but will pay off in the long run. IMO. good luck with your decision.

 

[Hemirunner]

If you stay around 1000hp or so at the flywheel you'll be ok. If you go over that in a heavy car, go with the TH400.

 

[ibsorgn]

If you stay around 1000hp or so at the flywheel you'll be ok. If you go over that in a heavy car, go with the TH400.

Astock 727 can handle 1000hp?

 

[HEMI-ITIS]

Not with traction:icon_hang:

 

[Hemirunner]

Astock 727 can handle 1000hp?

Not at all but what fool would put one behind a stroker engine? 1000hp is about the limit of a race built 727.

 

[451Mopar]

My 4,150# Charger ran mid 12's @ 110 MPH for years with a stock transmission with just a shift kit and the old 451 stroker. When I built the 500" stroker with over 100 more HP than the 451, I pulled the trans apart to freshen it, and the clutches still looked good, but some of the front planet gear splines fell out (good thing I pulled it apart.)
For safety and improved performance, I installed the super sprag (I think it has 16 rollers?), and a billet steel front drum. Because the new front drum takes an extra disc, the rear drum needs to be beveled for clearance, so I just ordered up the billet aluminum drum too, along with the billet steel front planetary gear. Those were most of the expensive replacement parts. I also used the red eagle frictions and kolene steels.
After I priced out what I paid for parts and shipping, I could have just about ordered a simular built trans from Cope Racing Transmissions for about the same money (around $3,000+.)

https://www.coperacingtrans.com/pro...id=33&osCsid=383b0f7ee1e60ea5e83b0103fda88adc

 

[ibsorgn]

This thread is getting to far removed from my original questions and is no longer helping me to make a decision. I think I will stay with the 727 and run it till it either breaks or proves that it is capable of handling my driving needs. Should it fail I will have it rebuilt to a level that will satisfy my demands plus a margine of strength. Appreciate your replies.

 

[HT413]

This thread is getting to far removed from my original questions and is no longer helping me to make a decision. I think I will stay with the 727 and run it till it either breaks or proves that it is capable of handling my driving needs. Should it fail I will have it rebuilt to a level that will satisfy my demands plus a margine of strength. Appreciate your replies.

Loosen up, bro. Your question was answered days ago, now the guys are teaching you how to make it stronger.

 

[SUPERSTOCKRACER]

This thread is getting to far removed from my original questions and is no longer helping me to make a decision. I think I will stay with the 727 and run it till it either breaks or proves that it is capable of handling my driving needs. Should it fail I will have it rebuilt to a level that will satisfy my demands plus a margine of strength. Appreciate your replies.

I didn't read the whole thread but:
Do you realize that when a transmission breaks, it usually takes out more than just the transmission.
Rearend pinions break as well.
I make 1246 hp and run a torqueflite and I have $6700.00 in it.
My other cars make a little over 1000hp and I have $5200.00 in those as well
First thing that will go is your front planetary, then sprag, at least buy a good rollerized planetary, front billet steel drum, and ultimate sprag with a good rear servo.
I've broke more transmissions over the years than most. It was a learning experience. An expensive one at that.

 

[bbcharger71]

If you decide to go for a 4 speed auto, look into a 4L65E. It's the tranny that is behind the LS motors. From the factory, I think they are rated for 500 ftlbs. With a mild build, you could easily get it up in the 600's. I'm putting a 4l60e (vortec tranny) in my charger. I have a 500+ hp big block it's bolted up to. With modern day transmissions, you have the best of both worlds. You have a low first gear for launches, overdrive for mileage, and full adjustablity of line pressures, shift points, torque converter lock up, etc. On top of all of that, they are almost the same size as a 727. So not cutting!!!

 

[ibsorgn]

Noted.

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If you decide to go for a 4 speed auto, look into a 4L65E. It's the tranny that is behind the LS motors. From the factory, I think they are rated for 500 ftlbs. With a mild build, you could easily get it up in the 600's. I'm putting a 4l60e (vortec tranny) in my charger. I have a 500+ hp big block it's bolted up to. With modern day transmissions, you have the best of both worlds. You have a low first gear for launches, overdrive for mileage, and full adjustablity of line pressures, shift points, torque converter lock up, etc. On top of all of that, they are almost the same size as a 727. So not cutting!!!

I take it that there are no modern mopar transmissions that are easily installed. How difficult was it to make the swap?

 

[bbcharger71]

What makes this swap so common is the removeable bellhousing. Quicktime makes a bellhousing for it to bolt right up. I had to build a crossmember and hammer back the body seam on the firewall for clearance. I have a thread started with my progress. http://www.forbbodiesonly.com/moparforum/showthread.php?48547-4L60E-to-a-Big-Block My biggest issue was Quicktime miss labeling the bellhousing which cause some issues with the torque converter. I have the engine running. I just have to finish building my brakes and rear end before I can test it out.

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And no, modern mopar transmissions will only bolt up to smalblocks.

 

[383man]

I know you have your answer on the stock 727 but I would like to say please do what Hemi-Itis said and consider running a trans shield. That way if you would blow the front drum apart you have some protection. Ron

 

[ibsorgn]

What makes this swap so common is the removeable bellhousing. Quicktime makes a bellhousing for it to bolt right up. I had to build a crossmember and hammer back the body seam on the firewall for clearance. I have a thread started with my progress. http://www.forbbodiesonly.com/moparforum/showthread.php?48547-4L60E-to-a-Big-Block My biggest issue was Quicktime miss labeling the bellhousing which cause some issues with the torque converter. I have the engine running. I just have to finish building my brakes and rear end before I can test it out.

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And no, modern mopar transmissions will only bolt up to smalblocks.

I will be running a Big Block

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I know you have your answer on the stock 727 but I would like to say please do what Hemi-Itis said and consider running a trans shield. That way if you would blow the front drum apart you have some protection. Ron

You recommend a safety shield for a street car?

 

[satman72]

I will be running a Big Block

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You recommend a safety shield for a street car?

Sure, why not. From your original post; "Car is mainly used for cruises, smoking tires and a little lite drag racing. The stroker will produce around 670FPT."

Put in the shield, be safe.

 

[ibsorgn]

Loosen up, bro. Your question was answered days ago, now the guys are teaching you how to make it stronger.

Sometimes these threads tend to wonder a bit. As I stated I appreciate all the replies, However I do get disquieted when someone talks down to me.
FYI, I'm quite loose Bubba, but you maybe wound a little tight.

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Sure, why not. From your original post; "Car is mainly used for cruises, smoking tires and a little lite drag racing. The stroker will produce around 670FPT."

Put in the shield, be safe.

I guess a roll bar wouldn't hurt either but when does it stop. Appreciate the suggestions.

 

[383man]

I will be running a Big Block

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You recommend a safety shield for a street car?

It can happen very easy on the street when someone is doing a burnout and dont realize that in normal low the L/R band is not applied and if they get off and then back on the gas it can cause problems when it breaks the overrunning clutch rollers and then things can blow up. Better to be safe then stupid ! Oh and I do have a rollbar in my street car. Ron

 

[ibsorgn]

It can happen very easy on the street when someone is doing a burnout and dont realize that in normal low the L/R band is not applied and if they get off and then back on the gas it can cause problems when it breaks the overrunning clutch rollers and then things can blow up. Better to be safe then stupid ! Oh and I do have a rollbar in my street car. Ron

Didn't know that. No more roll bars for me getting to old to be climbing around them. Hell, might even install A/C, setting in the staging lanes sometimes get very hot!

 

[383man]

Didn't know that. No more roll bars for me getting to old to be climbing around them. Hell, might even install A/C, setting in the staging lanes sometimes get very hot!

I understand what you are saying. I have to have atleast a 6 point rollbar which is what I have because I do race my car sometimes and I did not want anymore then the 6 point bar in my street car because as you mean its more bars to hit your head on driving on the street. But I love to race when I can so I put up with it. Ron

 

[PDFROGMAN]

I will throw my 2 cents in
built correctly a 727 will suit your needs
if you decide not to use a billet front drum I strongly suggest a shield
if you are doing a burn out in first gear and the tires hook up after they were spinning you will grenade the rear roller clutch and the front drum will be spining 2.42X engine RPM and have been know to explode just from centrifugal force.

i would not suggests a 4L65E, it is a weaker unit than a stock 727
besides the the hassle of finding a way to control it you will need to throw $ into beefing it up.
I like that unit because there are lots out there and I make money rebuilding them