727 vs PG

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68 barracuda 68

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hello,
Im getting build a new 408 engine, hopeffully around 550-600hp i have a tci 727 and dynamic 3800-4200 stall, thinking on changing to PG will that give me better ET or just wasted money?
 
I think one of the advantages of the PG are parts availability and prices on those parts.
 
How heavy is the car? I researched going to a power glide but decided against it.

From what I can tell if you are lighter than 3,000 lbs the PG will be quicker. Heavier than 3,000 and the 3 speed will be quicker.
 
Walker434 said:
How heavy is the car? I researched going to a power glide but decided against it.

From what I can tell if you are lighter than 3,000 lbs the PG will be quicker. Heavier than 3,000 and the 3 speed will be quicker.
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Thanks, the car is about 3000lbs.
 
Glide is usually lighter and less parasitic drag. I run with a guy who runs a chevy 2 at 3000lbs with a glide, in fact he just broke the case all the way around the bell area.
 
All else being equal in a street/strip car a properly built 904 or 999 will be quicker and safer, but track car only with deep gears go with an aftermarket powerglide. To quote Herb McCandless "A properly built 9 inch drag race Ford rearend is built with no parts actually made by Ford, a properly built drag race powerglide has no parts made by GM".
 
Good responses ! In order to take advantage of a Glide you must have a high horsepower motor . Which you have . This is because of the drop in rpm from only having 2 speeds . glides are also lighter . they are not any more consistant than a race prepped TF . the latest thing here in the East Coast is a Fred Smith Transmissions AOD4 with a tranny brake and lock up converter . We have gone high 10 s , 3200lbs., 100% street legal . Nice trans but super pricey .
 
I have yet to see the most pertinent information regarding the 2 speed to 3 speed comparison. Rear gear ratio. Also, dollar for dollar, the PG will take a lot more abuse. Here starts the argument. lol
 
Absolutely! Powerglides require much lower gearing to work properly, which is why low gear sets of 1.58 to 1.72 are popular in drag racing 'glides. Less rpm drop between shifts for something that is meant to make peak power at insanely high rpm levels. Of note is the new drag race two speed transmissions based on a turbo 400, as they actually usually utilize a second gear set with ratios of 1.53 to one 1.23 for a first gear set. Top dragster, super boosted, or nitrous pro modified type setup, far outside the realm of "normal" for most of us... Lenco territory!
 
are you ever gonna get to use the 3rd gear? wind second out until the traps?
 
If you want an expert opinion...Call Dave Smith at Pro Trans In Palmdale California...before he moves to Texas...LOL..

I see you are in Norway....but they build the best 904 aka ProFilte...they build a lot of PG too...
 
Some good powerglide info here, and some bad.
I switched over my at the time 2900 pound 1982 big block Dodge Charger around 25 years or so ago. It ran almost exactly the same with a stock 1.76 low gearset. It was about .07 quicker with the six cylinder 1.82 but that gearset only lasted 100-125 runs before it broke. The stock 1.76 gears knock on wood I never broke even running low 8.40's@160mph. Now behind the small block in my black Duster I now run an after market 1.98 and it 60 foots .07 quicker than the stock 1.76 but runs the 1/8 mile almost exactly the same 6.00 ET at 2860 pounds. I have 3 ATI Powerglide Super Cases now and tonight I will finish up the 1.69 gearset for my 572 heads-up car. Next one going together after that is a 1.80 gear-set one. The stock cases work great but I cracked one last year so I'm gun-shy.
 
My buddy who broke the case got it with the car which before he got it was a 9 second nitrous car. It was probably hurt before he got it. Its not like he SHOCKING the hell out of it on a f70-14 redline tire. Funny it only leaked because the trans rotated and pull the dipstick tube out! He’s still deciding whether to go glide or three speed. He likes the odd ball nature of the only glide in the class.
 
pishta said:
are you ever gonna get to use the 3rd gear? wind second out until the traps?
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If I am following your question correctly, second gear becomes the new low gear and direct/high "third" is the new second gear. I don't know what gets deleted to make first inoperable but I would think the gearset would still be there to enable reverse.
 
ive did reseach on this lots of times,most say pg good for a lite weight car which I agree,i have 2 lite weight darts wouldn't mind trying a pg,then your getting into deciding which gear ratio works best,then have to build another trans mount and driveshaft,also shifters,there are more shifters out there for pg than 727,more parts for pg,cheaper,dime a dozen,more people to work on them than 727,i had a 727 go off at the line onme,no fun,but there was signs it was coming,pg take less hp to turn than a 727,think the 727 goes off like a bomb more with transbrake than foot brake

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any time you break something in the driveline while the 727 is in low gear.....the 727 needs to be removed and the roller and springs in the rear sprag need to inspected or changed out....failure to do so can cause the trans to explode ....foot brake or transbrake.....it goes boom....
 
Some of the information online about the 904 in testing shows that the smaller clutch drums have been tested to over 26,000 rpm before failure. That is usually past what the gear cluster can spin the clutch drum in event of a sprag failure. The same testing also shows that the drum doesn’t grenade out like the heavier 727 does. Another advantage for the 904 is the availability of low gear sets made by Ma Mopar.
 
I’m betting 98% of 727 transmissions exploding is caused by improper tire heating and failure to inspect the transmission after a low gear parts failure
 
pittsburghracer said:
I’m betting 98% of 727 transmissions exploding is caused by improper tire heating and failure to inspect the transmission after a low gear parts failure
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Yes, improper tire heating... not getting the transmissions into high gear soon enough during a burnout or letting off the throttle during a burnout in first or second with a full race valve body with no compression braking in first or second. Always caused by the springs and rollers being folded over in the sprag and allows the front drum to be spun at an overdrive ratio of the first gear set at launch. There was a Chrysler Power (remember them?) article called “exploding torquflites” that covered it in great detail. Another argument to be made for the strength of the 904 was the super stock hemi class folks that were paying mega dollars for big block pattern 727s modified internally for 904 rotating assemblies. The 904 is also just simplerwith fewer internal parts as well...
 
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Garrett Ellison said:
All else being equal in a street/strip car a properly built 904 or 999 will be quicker and safer, but track car only with deep gears go with an aftermarket powerglide. To quote Herb McCandless "A properly built 9 inch drag race Ford rearend is built with no parts actually made by Ford, a properly built drag race powerglide has no parts made by GM".
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I got to hear Herb McCandless speak this summer at carlisle and he said in the 60's and 70's the only time Ford and Chevy stood a chance was when they used mopars trans and rear ends because everything else broke to much to be reliable
 
I am looking forward to doing transgo manual shift, may drop the hammer on a low gear set from A&A and a 5 disk set clutch pack kit...
Big Green Duster said:
I got to hear Herb McCandless speak this summer at carlisle and he said in the 60's and 70's the only time Ford and Chevy stood a chance was when they used mopars trans and rear ends because everything else broke to much to be reliable
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Wow! It was ‘98 in Bristol when I heard him at one of the performance seminars he was hosting and he was talking about 904 internals inside of a 727 case and the 9 inch ford... I still laugh at the quote “The most important thing to know about a 9 inch ford and reliability is that in when we build one, we use no parts that are actually made by ford, including the housing... it actually costs just as much if not more to build one instead of a Dana and the Dana has less frictional loss than the ford rearend” It still amazes me how much technology in our hobby has changed since back then... I especially remember an older gentleman venting about the new generation being raised by MTV and them believing the junk they had was worth a fortune... all I can think now is I really feel for him if he’s around now to witness our up and coming generation...
 
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