Horse Power

[oldbee]

Like PR says, I've laughed more than once at YouTube videos of some of the "power shifts" that are shown. Ronnie Sox and others are awful hard to match in that regard and able to do it consistently.

 

[HEMI-ITIS]

PR correct me if I'm wrong,but even with a shitty pass if you run it out the back door you can still figure HP with MPH & weight.

 

[PRHeads]

If there are subtle changes from one run to another the ET will change more than the speed.

When the numbers are way way off(as is the case with Al’s car), it’s because the average rate of acceleration for the entire pass is lower than it should be(way lower).
In these situations, IMO, the numbers really aren’t telling you anything except the combo isn’t working.

Sometimes a little common sense must be applied to the results.

I have seen people improve their ET’s and trap speeds dramatically without changing the power output of the motor or the weight of the car.
I’ve seen converter swaps pick up 3mph+.
In a 3800lb car in the 120mph range, that shows a 30hp gain, yet nothing was changed in the motor.
The 3mph came from wasting less, not making more.
The “combination” improved.

That’s part of the value of reliable dyno results.
If you know what the motor makes, and the track numbers are way way off........ you know not to spend a bunch of time and $$$ looking for more power.
In that scenario....... the power isn’t the problem.

 

[Cranky]

To me it’s obvious when you watch a car like that.
It’s harder to get the car to a point where you can side step the clutch on the line at around 5k and have that yield a positive result....... one that rivals what a car with an auto and a good converter would put up for a number.
Then, there are 3 shifts to make going down the track....... at high rpm, with a trans that’s often set up less than optimally for power shifting.
And then on top of that, there is a certain amount of skill involved to quickly and efficiently making those 3 shifts....... and it seems that not everyone can do it like Ronnie Sox.

So, the auto car is more or less fool proof.
Stick it in “D” for drag........ mash the throttle and enjoy the ride.

I’m not saying the streeter stick car can’t run the number it “should”...... I’m just saying my observations are that they rarely ever do.

Again, not picking on Al here....... but so far at least, his car falls right into that category(for all 3 of the reasons I mentioned).

Of the runs of his car I’ve seen(and I’m acknowledging there may have been other trips to the track where better results were achieved. I’m basing this off about 1/2 a dozen passes on one day)..... assuming a race weight of around 4000lbs, using the Moroso calculator, the best one I saw shows a number about 150hp lower than 10% off what I’d expect to see for STP power on an engine dyno for his motor combo.

The on track performance is a reflection of the complete package....... not just the engine output.

In this particular application, compared to how the car was being run on the video I saw, there is no doubt in my mind that if you swapped the 4 speed for a nice 727 and a good 9.5” converter the numbers would make it look like the motor picked up 100hp+.

With a history that goes back a long ways as a stick guy, I had got lots of practice on the street before actually getting behind the wheel of a 10 second drag car with a stick that was properly set up. Man, it was a sweet running car too but one thing we NEVER did was side step the clutch pedal. Yeah, even though a slight amount of slip will usually be helpful in many cases with a competition clutch, side stepping isn't the best way to launch a consistent drag car and imo isn't something that's needed doing anyways. With a street car, it usually means broken parts too. And yes, Mr Sox could shift but did he mention side stepping? Never heard it unless he was cracking a joke. Have I ever done it? Yup. It surprised me that it shocked the car so severely (street car) and was somewhat glad that my rpm wasn't very high lol. It might be ok if you have a setup to keep a very slight drag on the drive train to take out all the slack before dumping but...well, why even bother doing that on a street car? The clutch wouldn't last for very long on the street.

 

[Cranky]

PR correct me if I'm wrong,but even with a shitty pass if you run it out the back door you can still figure HP with MPH & weight.

Doesn't running out the back door mean staying in it beyond the finish line? There are no timing lights past the finish line anymore that I know of....

 

[PRHeads]

“Side stepping”.....”popping”..... just semantics.

No one I’ve talked to running a Stocker with a stick does anything except release the clutch as fast as they possibly can.



And this car runs good enough that the hp numbers on the calculators are quite a bit higher than the actual hp the motor makes.
(Went 10.37@128.68@3300lbs last weekend)

 

[HEMI-ITIS]

Doesn't running out the back door mean staying in it beyond the finish line? There are no timing lights past the finish line anymore that I know of....

Your wording would be correct,,,,,to the stripe.If my tires spin off the line the MPH only varies maybe 4 or 5 MPH.

 

[Cranky]

“Side stepping”.....”popping”..... just semantics.

No one I’ve talked to running a Stocker with a stick does anything except release the clutch as fast as they possibly can.

View attachment 921386 View attachment 921387

Ask them how they 'release' please. I'm serious. No one I know that runs a fast stick car side steps the pedal. They release it by letting up as fast as they can. I'll be the first to admit that side stepping does let the clutch engage faster/quicker but it also requires you to bring your foot back over the pedal for the 1-2 shift....unless you are running a clutchless set up......

 

[PRHeads]

There’s a guy on moparts with a very street driven RR with an Ede headed 493 in it.
Runs high tens....... leaves at 5k......833 trans.

One of the better running examples of that type of true street combo.

Just go back to my earlier post and replace the words “side step” with “pop”.
For the average poorly sorted out stick shifted street car, the difference in the result will be negligible at best.
The gist of what I was getting at is, it doesn’t appear the typical street driven stick car is set up to be able to take advantage of an aggressive starting line technique.
It usually results in spinning, or broken parts, or both.
If you’re manually “slipping” the clutch, you’re leaving some 60’/ET on the table....... which will also make the power numbers look worse.

Or, perhaps someone can give a better explanation of how a 600hp motor looks like it’s down 200hp when looking at the track results.
I’m comfortable with my assessment of why the numbers often look like they do........ but others may have some differing insights on the matter.

 

[33 IMP]

If there are subtle changes from one run to another the ET will change more than the speed.

When the numbers are way way off(as is the case with Al’s car), it’s because the average rate of acceleration for the entire pass is lower than it should be(way lower).
In these situations, IMO, the numbers really aren’t telling you anything except the combo isn’t working.

Sometimes a little common sense must be applied to the results.

I have seen people improve their ET’s and trap speeds dramatically without changing the power output of the motor or the weight of the car.
I’ve seen converter swaps pick up 3mph+.
In a 3800lb car in the 120mph range, that shows a 30hp gain, yet nothing was changed in the motor.
The 3mph came from wasting less, not making more.
The “combination” improved.

That’s part of the value of reliable dyno results.
If you know what the motor makes, and the track numbers are way way off........ you know not to spend a bunch of time and $$$ looking for more power.
In that scenario....... the power isn’t the problem.

I agree with Dwayne. When I replaced this converter, I picked up two tenths and two mph in the eighth, compared to when it wasn't broke, obviously .

 

[PRHeads]

IMO, Al’s motor/car combo should be able to easily run in the lower mid-11’s, and 60’ in the lower to mid 1.50’s, somewhere in the 117-120mph range.... with a 727 and a suitable 9.5” converter and 3.91/4.10 gearing.

I have no idea what the 60’ times were at the track rental with the 4 speed, but I’m guessing over .50 slower in just that short distance.

Al..... what was your best 60’ that day?
Have you been to the track since?
Any better performance to report?

 

[biomedtechguy]

I absolutely respect the vast experience you all have.
I enjoy rowing the gears so much that I'm willing to concede that I may go faster with an automatic transmission vs the manual transmission, and that goes for both of our classic muscle cars.
Both my wife and I are ADAMANT about having the 3rd pedal, it adds a degree of additional skill and pleasure, and as we both get better at shifting we can look at those improvements with a sense of accomplishment.
On top of that, the Pistol Grip is correct for my car, I always looked through the side window of cars I liked to see if if was auto or stick, my wife is worse with that than I am, and won't give an auto transmission car a second look, no matter how nice the rest may be.
So it's a different kind of thing for us, and I still think the HitMaster is going to bring some impressive results for me to post here, so much so that I just ordered a Hydramax hydraulic throwout bearing for her car which is about to get the TKO600 sitting in a box put in place of the Muncie in the GTO. That way if I get the kind of results I expect, that many others have from a properly adjusted HitMaster or Clutch Tamer, I can get one for her car, set it up, and tell her to bring the engine up to the x,*** RPM range, and at the launch, release the clutch completely and floor it. The HitMaster does the rest for the launch.
Once the 540 cu in beast is in my Roadrunner, the HitMaster has a 2nd stage that can be setup to help keep additional gear changes from breaking the tires loose.

 

[oldbee]

Gotta agree with Dwayne, sticks are violent to every part of a car when launched correctly.

 

[Cranky]

Gotta agree with Dwayne, sticks are violent to every part of a car when launched correctly.

It's even worse when done incorrectly lol

 

[BSB67]

Converters will eat power (mph). So a good one verses a not so good one will show up in the mph. I've seen 3 mph in a 400 hp application. But a manual transmissions doesn't. I've made a lot of passes with a manual, and as long as the shifts are reasonable, mph is always close. The et might change a full second or more due to the launch.

Same with my automatic. I've run back to back runs with the et being different by over one second, but run the exact same mph. Change tire, gear, suspension (not converter) way better et, same mph (maybe less).

I've always been amazed how if nothing is "wrong", make consistent shifts, and you don't mess with the rotational weight, how consistent mph is.

Mopar use to have P/W and W/P tables and showed the manual cars with higher mph than the autos for the same power, but certainly presumed the theoretical best. That was long ago, and autos have gotten better.

I think when SS magazine did the A12 4 speed car tests with Ronnie driving it went almost 111, but 110. and change with an amateur driver.

Just my experience and observation.

 

[oldbee]

Converters will eat power (mph). So a good one verses a not so good one will show up in the mph. I've seen 3 mph in a 400 hp application. But a manual transmissions doesn't. I've made a lot of passes with a manual, and as long as the shifts are reasonable, mph is always close. The et might change a full second or more due to the launch.

Same with my automatic. I've run back to back runs with the et being different by over one second, but run the exact same mph. Change tire, gear, suspension (not converter) way better et, same mph (maybe less).

I've always been amazed how if nothing is "wrong", make consistent shifts, and you don't mess with the rotational weight, how consistent mph is.

Mopar use to have P/W and W/P tables and showed the manual cars with higher mph than the autos for the same power, but certainly presumed the theoretical best. That was long ago, and autos have gotten better.

I think when SS magazine did the A12 4 speed car tests with Ronnie driving it went almost 111, but 110. and change with an amateur driver.

Just my experience and observation.

Not so much the autos, but the converters way better!

 

[BSB67]

Not so much the autos, but the converters way better!

You are correct. I misspoke.

 

[PRHeads]

Russ, would you expect the trap speed to remain very close if one run was made with a hard launch resulting in a good 60’ time and then have quick power shifts down track......... and another was made with a very soft “walk it out” launch and granny shifts down track?

I wouldn’t, but that’s just my gut feeling.
Be fun to have someone do the test.

 

[BSB67]

Russ, would you expect the trap speed to remain very close if one run was made with a hard launch resulting in a good 60’ time and then have quick power shifts down track......... and another was made with a very soft “walk it out” launch and granny shifts down track?

I wouldn’t, but that’s just my gut feeling.
Be fun to have someone do the test.

My opinion would be the launch would not change the mph, in a consistent and meaningful way. The granny shifts would, but not by a bunch. For the granny shifts, I think it would be like shorting the track the same distance the car travels between shifts not under power.

It would be fun. Heck, maybe getting one of these cars out of the garage and back to the track would be fun.

 

[PRHeads]

For the granny shifts, I think it would be like shorting the track the same distance the car travels between shifts not under power.

That’s pretty much my take on it as well, only maybe even more detrimental than the loss of “length”, since on the granny shifts you are(can be) slightly decelerating during that time, and you have to overcome that when you’re finally back on the gas.

You know how it is during the in car camera footage...... where the upper body is seen swaying for and aft during the shifts.