Race prepped c6 verse race prepped Powerglide

When is the last time someone really took the time to weigh a race prepped c6 and a race prepped  power glide that has the bbf bell added to a stock case and then weigh a aftermarket power glide case that has been race prepped ?  I think you all would be surprised at how little amount of difference there really is.

Also when is the last time anyone has some true back to back testing Dyno time to see the real power losses ?
I haven't heard or read anywhere  that anyone has take the time to dial a race prepped c6 with time slips and then swapped in a race prepped dialed in power glide and document the difference.  This would be time consuming and money being rear gear ratio and torque converter tuning !

Most swap from a wore out c4 to a glide or a stock c6 with a shift kit to a glide. There are those that just swap for a race prepped c4 to a glide and see some difference.
This is not a c4 verse power glide topic it is c6 versus power glide !

I do understand the laws of physics that two shifts are suppose to be faster than three .



I also understand  that torque and the starting line and trans gear ratios make a difference.

Now let the facts and true hands on debate and info start no Wikipedia or copy and paste or second cousins brothers uncle s girlfriends dads B.S .

I don't believe all those old figures thrown around re HP use of the different transmissions

This could be interesting

We did some testing here awhile back but never with the C6 to P/G swap

So not much help but I will throw it out there if it's ok.

P/G vs t5 vs c4 vs race built AOD

Gregaust wrote:I don't believe all those old figures thrown around re HP use of the different transmissions

This could be interesting

I went from a TH400 to a TH350 hoping for a tenth or two in the eight mile and picked up nothing. It did not last long either on the nitrous, but I could not brake the 400 and it was not from lack of trying.

I think it's hard to get accurate comparitive data because you have to change the converter with a C6 to Glide swap and a lot of people changes gears out to. The variables make the comparison unreliable and flawed. On the 350 to 400 deal I used the same converter, but different track/weather conditions ect. ect. you know the deal.

supervel45 wrote:I think it's hard to get accurate comparitive data because you have to change the converter with a C6 to Glide swap and a lot of people changes gears out to. The variables make the comparison unreliable and flawed. On the 350 to 400 deal I used the same converter, but different track/weather conditions ect. ect. you know the deal.

In our testing it was a 89 mustang coupe
306 with 175hp worth of nitrous
4.10 gear 28x10.5 slick

AOD--11.7
T5--11.5
C4--10.98
P/G--11.2

Change nothing but converters as we did swaps kept the stall the same where these deals optimum prolly not but we wanted to see what would work and change nothing but trans stuff... the car finally went it's fastest time with a c4 and more nitrous

That AOD number does not surprize me at all, they always were pigs.

supervel45 wrote:I think it's hard to get accurate comparitive data because you have to change the converter with a C6 to Glide swap and a lot of people changes gears out to. The variables make the comparison unreliable and flawed. On the 350 to 400 deal I used the same converter, but different track/weather conditions ect. ect. you know the deal.

That is the point The data is flawed and un reliable now .What I feel is the best comparison is race prepped both transmissions with the correct rear gear ratio and correct stall speed for each transmission . With both race prepped !

I understand what you are saying trac temps weather tire psi ect would be a factor to be accounted for at test time and it may take several outings with same trans to get a good comparison .

Also don't for get the level of HP and the level of competition some of these guys are at. For most of us the difference is semantics and we would be better off not worrying about it and concentrate on other area's of the vehicle if you have a good working transmission. I know I would have been when I swapped, especially if you don't like freshening of replacing parts on the weaker unit's or having to do much vehicle modification for the swap. The other thing about a glide being faster in a 3,000 pound car or lighter is not absolute either apparently if you make enough horsepower for a heavier car. It's like anything else, we can debate it till we are blue in the face with everyone's personal experience and 2+2 still may not equal 4 if big brother says it doesn't.

gmsmkr wrote:

supervel45 wrote:I think it's hard to get accurate comparitive data because you have to change the converter with a C6 to Glide swap and a lot of people changes gears out to. The variables make the comparison unreliable and flawed. On the 350 to 400 deal I used the same converter, but different track/weather conditions ect. ect. you know the deal.

In our testing it was a 89 mustang coupe
306 with 175hp worth of nitrous
4.10 gear 28x10.5 slick

AOD--11.7
T5--11.5
C4--10.98
P/G--11.2

Change nothing but converters as we did swaps kept the stall the same where these deals optimum prolly not but we wanted to see what would work and change nothing but trans stuff... the car finally went it's fastest time with a c4 and more nitrous

This is what I am looking for ,but the c6 versus the Powerglide !

supervel45 wrote:Also don't for get the level of HP and the level of competition some of these guys are at. For most of us the difference is semantics and we would be better off not worrying about it and concentrate on other area's of the vehicle if you have a good working transmission. I know I would have been when I swapped, especially if you don't like freshening of replacing parts on the weaker unit's or having to do much vehicle modification for the swap. The other thing about a glide being faster in a 3,000 pound car or lighter is not absolute either apparently if you make enough horsepower for a heavier car. It's like anything else, we can debate it till we are blue in the face with everyone's personal experience and 2+2 still may not equal 4 if big brother says it doesn't.

Not a debate just the facts !

Went from a full tilt roller c4 to a glide in my old sbf car and the glide was quicker and faster, that deal made no torque whatsoever. The glide will last a hell of a lot longer in that car and take more power down the road also.

I went from a stock c6 with a shift kit to a $$ c4 and used the same converter with NO other changes and didn't gain $hit! After a few years and motor swaps as well as several converters I went PG and had the same results! The Sfi case is a heavy piece but it is SFI and sets beside you with little to no protection. Most of the debate comes down to what the combo wants and lots and lots of variables.

richter69 wrote:Went from a full tilt roller c4 to a glide in my old sbf car and the glide was quicker and faster, that deal made no torque whatsoever. The glide will last a hell of a lot longer in that car and take more power down the road also.

Rear gear ratio with c4 and rear gear ratio with Powerglide ? Stall speed for c4 stall speed for glide ?

Tech information and time slips ?

I really would like a some c6 and glide comparison and info.

Hey HeRo:

The man said: "This is not a c4 verse power glide topic it is c6 versus power glide !"

Just the facts ma'am.

I posted facts about my experience, if a low torque sbf car will go faster w a glide when it already had a killer low power robbing c4 just imagine what a difference it would make going from a school bus transmission to a glide.

Carry on.....

Oh, it gained .005 in et and 2 mph. Tbe c4 convter would go 4300 and the glide 2900..... Glide converter was way tight i suspect if it were looser the et gain would have been a good deal more. Rear gear the same.

Car would would wheelie harder w the glide also. Remember this is a 3.00" stroke combination..... No torque.


A lot of it boils down to those who will never own a glide cuz it a "chevy" part. None of my engine, trans or rearend parts are ford or chevy made.... All aftermarket...

I could care less what others do only my program matters to me. I'll share my experiences when i can or choose to, if you want to better your own program or not with that info I could give a damn....

See ya in the lanes....

Combination of your car and engine, heavy car, peaky big block, small inch 500 or less and big heads, I think the three speed C6 would be where one would want to be. narrow tq peak to hp peak the three speed would fall back on the peak tq better.

Big inch, light car, wide tq curve, Glide will be the ticket.

Some where in the middle, well I would say it would end up being a wash...........

No concrete info or time slips, just my 2 cents worth..........

richter69 wrote:Oh, it gained .005 in et and 2 mph. Tbe c4 convter would go 4300 and the glide 2900..... Glide converter was way tight i suspect if it were looser the et gain would have been a good deal more. Rear gear the same.

Car would would wheelie harder w the glide also. Remember this is a 3.00" stroke combination..... No torque.


A lot of it boils down to those who will never own a glide cuz it a "chevy" part. None of my engine, trans or rearend parts are ford or chevy made.... All aftermarket...

I could care less what others do only my program matters to me. I'll share my experiences when i can or choose to, if you want to better your own program or not with that info I could give a damn....

See ya in the lanes....

Really in my opinion it has nothing to do weather it is a Chevy part or not ! I just wanted to see What ET and hp along with weight difference and if anyone had done a real world comparison with c6 versus glide !

It has nothing to do with my program and it is a forum you are free to post or not post !

IDT-572 wrote:Combination of your car and engine, heavy car, peaky big block, small inch 500 or less and big heads, I think the three speed C6 would be where one would want to be. narrow tq peak to hp peak the three speed would fall back on the peak tq better.

Big inch, light car, wide tq curve, Glide will be the ticket.

Some where in the middle, well I would say it would end up being a wash...........

No concrete info or time slips, just my 2 cents worth..........

Thank you sir !

The argument is a moot point on a car fast enough where you might want/need a beefier/stronger/safer SFI legal trans case since a SFI C-6 case isn't an option at this time. A SFI C-6 case might be available someday if someone decides there's enough demand for one.

In this situation you could get kinda close to having a SFI C-6. Just buy a LencoDrive trans with a C-6 input shaft & use a C-6 converter.

You can always use a SFI blanket. That's what I have.

738drvr wrote:You can always use a SFI blanket. That's what I have.

That might be fine for a car with an unmolested/sealed factory floor. But on a belly pan car if the OEM case fails that blanket might catch some of the shrapnel, but won't keep the hot trans oil/oil fire off you. OEM case + SFI blanket does not equal the safety of a beefy SFI case, or the SFI case + liner.

DILLIGASDAVE wrote:

738drvr wrote:You can always use a SFI blanket. That's what I have.

That might be fine for a car with an unmolested/sealed factory floor. But on a belly pan car if the OEM case fails that blanket might catch some of the shrapnel, but won't keep the hot trans oil/oil fire off you. OEM case + SFI blanket does not equal the safety of a beefy SFI case, or the SFI case + liner.

J.W. offers a shield and I am sure you can run the blanket with it .
SFI 4.1 Certified.

I know that is not the same as having a good case !

This still has nothing to do with hp and tq lose or gain between the two transmissions.

Even with an SFI case there has to be a significant weight difference between the 2. In my case my smaller C6 converter takes weight out but the deep aluminum pan add's weight. I can't help you with this one, chevy parts or not I just can't bring myself to put a glide in my Ford...Maybe someday when I'm grasping for an ET drop I'll swallow my pride and buy a glide but I don't see that day coming anytime soon..LOL...2 shifts is just fine with me.