Switching from foot brake 727 to power glide with brake

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Phil hull

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Looking for suggestions. I’m thinking about putting a power glide in my car that has a trans brake and pulling the foot brake 727 out. I currently run a 1.56 60 ft leaving at 3500 off the foot brake and I realize the power glide has a 1.76 gear but if l leave off the brake at 4600 or so rpm should I expect the 60 ft to still slow down? Running a 270/280 620/625 roller cam in a 3000 lbs race weight car. Any help or suggestions is appreciated thanks!
 
I’ve seen this type swap on many cars that I would call marginal !! What I mean by that is a car that may or may not have enough horsepower to pull the power glide!! Generally speaking the cars I’ve seen with the numbers you have given actually slowed down in ET.. The cars just didn’t have the power to pull the power glide !! The higher horsepower cars seem to do really well with the swap !!
 
Rmoore said:
I’ve seen this type swap on many cars that I would call marginal !! What I mean by that is a car that may or may not have enough horsepower to pull the power glide!! Generally speaking the cars I’ve seen with the numbers you have given actually slowed down in ET.. The cars just didn’t have the power to pull the power glide !! The higher horsepower cars seem to do really well with the swap !!
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Thanks for the info that’s kind of what I was thinking as well. Car has a 383 making about 525 hp best ET is 10.86@124 but I do plan on putting a 451 in it next year which hopefully should make enough power to pull through it.
 
Phil hull said:
Thanks for the info that’s kind of what I was thinking as well. Car has a 383 making about 525 hp best ET is 10.86@124 but I do plan on putting a 451 in it next year which hopefully should make enough power to pull through it.
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I just hate to see anyone go through the motion and spend the money And could possibly slow down ! To me you are on the fence !! You may be ok !! Or you may not !! Your close either way
 
Rmoore said:
I just hate to see anyone go through the motion and spend the money And could possibly slow down ! To me you are on the fence !! You may be ok !! Or you may not !! Your close either way
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I have had the glide for a while now and everything to put it in I was going to wait till I put a bigger motor in the car but think I’m going to put it in right now. I’m having issues turning it red off the foot brake I have to split the bottom bulb to turn it green. I have put the biggest front tires on the car that I can with the fenderwell headers I’m running and figured why not put the glide in with a brake and if I need it I also have an adjustable trans brake switch I can put in the car. Ya it would suck to have my ET slow down but if I can’t turn it green every round then I can’t win races.
 
Phil hull said:
Thanks for the info that’s kind of what I was thinking as well. Car has a 383 making about 525 hp best ET is 10.86@124 but I do plan on putting a 451 in it next year which hopefully should make enough power to pull through it.
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you need to work on why the car is 60 footing poorly at the weight it is, and the ET it runs.
Would need to see what cam, convertor, gears, Heads, suspension etc you are currently using.
My car, for example( nothing special) typically runs 11.40’s in normal summer air around here at 3300 pounds. Goes 1.52-1.55 60 foot, and its maybe 10 to 1 compression smallblock. So lots heavier, less power.
Going to a 2 speed makes convertor selection and other factors more critical, or else the car will definately slow down, assuming its sticking now.Three speed has more room for error in it to enable a better 60 foot unless you have big power you are dealing with. A high 10 sec, light car doesn't have big power, so ironing things out should be pretty straightforward
 
B3422w5 said:
you need to work on why the car is 60 footing poorly at the weight it is, and the ET it runs.
Would need to see what cam, convertor, gears, Heads, suspension etc you are currently using.
My car, for example( nothing special) typically runs 11.40’s in normal summer air around here at 3300 pounds. Goes 1.52-1.55 60 foot, and its maybe 10 to 1 compression smallblock. So lots heavier, less power.
Going to a 2 speed makes convertor selection and other factors more critical, or else the car will definately slow down, assuming its sticking now.Three speed has more room for error in it to enable a better 60 foot unless you have big power you are dealing with. A high 10 sec, light car doesn't have big power, so ironing things out should be pretty straightforward
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I agree with you the best 60 ft the car has ever done is a 1.52 but it has gone away over the last year or so maybe the converter I’m currently running? 8 inch tci stock leaf springs with caltracs 12:1 compression with edlebrock performer rpm heads and the cam is 270/280 620/625 solid roller on a 108 I believe it’s to much cam for a foot brake since the rpm range is from 4500-7300 but hopefully it may work better with a trans brake leaving at about 4600-4700 running 4.10 gears currently but will put 4.56 in i when the glide goes in the car
 
Phil hull said:
Thanks for the info that’s kind of what I was thinking as well. Car has a 383 making about 525 hp best ET is 10.86@124 but I do plan on putting a 451 in it next year which hopefully should make enough power to pull through it.
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the 3500 stall convertor is not doing your 60 ft good with a 383. 4800 at a minimum. prefer 5000
 
fishmens67 said:
the 3500 stall convertor is not doing your 60 ft good with a 383. 4800 at a minimum. prefer 5000
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Wish I could get more out of it but being a foot brake that’s about all I could get. And at that the suspension is about all the way flexed out already when I leave the line
 
I think a 5000 stall and 4.56 gear would do wonders for your combo.
 
Phil hull said:
I agree with you the best 60 ft the car has ever done is a 1.52 but it has gone away over the last year or so maybe the converter I’m currently running? 8 inch tci stock leaf springs with caltracs 12:1 compression with edlebrock performer rpm heads and the cam is 270/280 620/625 solid roller on a 108 I believe it’s to much cam for a foot brake since the rpm range is from 4500-7300 but hopefully it may work better with a trans brake leaving at about 4600-4700 running 4.10 gears currently but will put 4.56 in i when the glide goes in the car
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If the convertor is well matched to the combo it should 60 foot the same,or awfully darn close either way.
I have posted this before. Had a high 9’s Smallblock stroker. I raced it 7 or 8 times a year in a points series that had a .400 pro tree 10 flat index race, and on those same nights, a footbrake bracket race.
Car went 1.35-1.36 either way i launched it, off foot, or at different Chip settings off the brake. Same exact ET either way, wheels up, or not so much in the air off the foot.
I will go a step further and say, regards footbraking, in any car i have ever had, whether i leave off idle, 1500, 2000, or as much as i can physically load it up and not have it creep, the 60 foot doesnt vary. Its still immediately headed to the flashpoint, like side stepping a clutch, before it accelerates from there
The reaction time will, of course change,but not the 60 foot.Further from the flash you footbrake it from, slower your reaction time will be, compared to leaving closer to the flash... not a ton... but some... useful in getting dialed in to the tree
Those results are having used super stock springs and ladder bars in different combos.

what does your convertor flash at? That does seem a huge cam. What gear?

edit... 3500 TCI convertor... from the sounds of it, likely you have a super street fighter type 10 incher. If so, that is 99% likely your problem.
A ten inch 3500 convertor and 270@ 50 cam equals... not good
 
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I would keep the torqueflight and get a custom stall convertor in the range of 5000.
4.10 is not enough gear for your combo.
Keep in mind a transbrake puts other parts at risk
 
B3422w5 said:
If the convertor is well matched to the combo it should 60 foot the same,or awfully darn close either way.
I have posted this before. Had a high 9’s Smallblock stroker. I raced it 7 or 8 times a year in a points series that had a .400 pro tree 10 flat index race, and on those same nights, a footbrake bracket race.
Car went 1.35-1.36 either way i launched it, off foot, or at different Chip settings off the brake.
I will go a step further and say, regards footbraking, in any car i have ever had, whether i leave off idle, 1500, 2000, or as much as i can physically load it up and not have it creep, and the 60 foot doesnt vary.
The reaction time will, of course, but not the 60 foot.
Those results are having used super stock springs and ladder bars in different combos.

what does your convertor flash at? That does seem a huge cam.
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Converter flashes about 4200ish it was a used converter when I put it in and have never sent it off to have it gone through. It may be nothing close to what I need for a converter it was just something I had lying around from a swap meet.
 
Phil hull said:
We will soon find out! I have about 3 weeks till my next race so I guess I’ll throw the glide in and see what it stalls at and hopefully it still sticks the tire!
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if it sticks now, you will have zero problems with the glide. If it was me i would fix what you have.
Car will run WAY better if you do.
Throw that convertor in the trash, buy something 500-5200 and hang on
 
The converter is going to stall what the converter is going to stall with or without a trans brake !! Engine horsepower has a lot to do with what the converter stalls !! You can put a 5000 stall 8 inch in a mini van ! You will be real lucky to get 2800 stall out of it tho!! Cause the mini van makes no horsepower !! Just saying !!
 
B3422w5 said:
that isnt killing you.
Switching to a 4.30 would probably make it trap 250 rpm higher.
Convertor is by far what i would pay attention to first.
It will spin more rpm if you get the car to pick up elsewhere with a good convertor
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I agree with everybody- more gear and higher stall converter, your 60 fts. should be in the 1.40s for that E.T. my small block Dart goes 1.49-1.51 60ft. going 11.50 on the stop.
 
That converter may have to much slip at the top end as well. A higher stall 5000 esh may make a lower rpm at the end of the track with the new converter, do to less slippage, aka more efficient

My new converter raised my stall from 3000 to 4200 and my trap mph was 2 mph slower but et and 60' much better.

In other words you may need to go to the 4.56 after a converter change.

I know your itching to put the 2 speed in but remember, you just added a new "class of learning" how to leave the line, how it reacts to leaving the line............exc
as far as punching red lights leave the line at lower rpm with slow your reactions, and you can keep leaving the line the say way and making it turn green.

i don't have a 2 step or a low rpm rev limiter.
but i do have a 2 step that does nothing but turn on a light. when i'm at 1500 rpm the light turns on in my dash and i know i'm ready to launch.

These are the kind of thing that you need to adj not a converter, or a 2sp.

A new converter will give you a better 60' but is not going to help you in your red lights at all.............Launch! RPM WILL. Just saying.
 

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