For bracket racing you want high slip ratio in the 1/8th, period. It isn't a pro mod, or 275 radial car that won't repeat from one run to the next. All out performance isn't what wins bracket races.

10% in the quarter is decent, but I would think that most are at, or above that level a few percent.

I asked Jason Lynch, who has won quite a few races, this same question and he told me a few percent doesn't change the MPH much, but can make the car less consistent.

quote:

Originally posted by Don Higgins Crew Chief Pro Software:
For bracket racing you want high slip ratio in the 1/8th, period. It isn't a pro mod, or 275 radial car that won't repeat from one run to the next. All out performance isn't what wins bracket races.

10% in the quarter is decent, but I would think that most are at, or above that level a few percent.

I asked Jason Lynch, who has won quite a few races, this same question and he told me a few percent doesn't change the MPH much, but can make the car less consistent.

I've won a few Super Pro bracket races myself. More than anyone in the history of Sunshine Dragstrip Clearwater Fl. by a bunch.

I'm gonna try and speak automotive performance fundamentals with you, they're not subjective.

I already know all this stuff and it benefits me zero to share it with you, especially when you make false claims and put a period on the end of a sentence like somehow that makes the claim fact ,when you obviously don't know yourself how it works, only going on second hand info.

I know Jason, excellent racer, one of my favorites, I've raced him in money rounds. Name dropping his name doesn't change automotive performance fundamentals either.

Fact of the matter is this, The only reason your torque converter is slipping 20% 1/8 mile, is because the car works good 1/4 mile too, with the starting line ratio and stall in play.

If I had a dragster, I'd have 1/8 gearing to cross with the converter slipping less than 10%, with the same starting line ratio and stall I'd have for 1/4 mile racing. If you and I had similar combo's, I'd be quite a bit quicker and faster than you after the shift 1/8 mile, and you'd be scratching your head why.

But then again I know how all this works, and you only know what you're told, second hand.

Plus I have nothing but a couple hours to lose, Because I can do all the work to make the adjustments in the transmission and rear end for 1/8 or 1/4 mile racing.

This message has been edited. Last edited by: Mike Rietow,

sometimes the rear gear will have an effect on slip %. I found out that switching from 4.56 to 4.86 on mine reduced converter slip % a little bit. Similar to boat props, when you get one "right", "slip" will reduce. On my little rig, I'm at 3% (the boat). The car is at 14% but I think it could use a little more rear gear.

Almost all engine builders will agree that on a naturally aspirated engine, the less load you put on the engine, the faster will be in the car. In turn, that makes them more consistent. In the power adder world, you keep adding power until you get the drive train happy, then figure out a way to tighten it back down, and add more power.

I'm not your typical bracket racer, but running Top Sportsman it's pretty important to be consistent. I run a Coan Super Mega converter and I see 0% slip at the 1/4 mile finish line. depending on the track i'm usually in the .99-1.02 60 ft range and the car has been surprisingly consistent for how wrong/tight the converter is.

quote:

Originally posted by 86BigBlockBird:
I'm not your typical bracket racer, but running Top Sportsman it's pretty important to be consistent. I run a Coan Super Mega converter and I see 0% slip at the 1/4 mile finish line. depending on the track i'm usually in the .99-1.02 60 ft range and the car has been surprisingly consistent for how wrong/tight the converter is.

Im assuming you have a power adder?

quote:

Originally posted by 329L:
Almost all engine builders will agree that on a naturally aspirated engine, the less load you put on the engine, the faster will be in the car. In turn, that makes them more consistent. In the power adder world, you keep adding power until you get the drive train happy, then figure out a way to tighten it back down, and add more power.

You're confusing the effect of stall early in the run and efficiency late in the run.

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by 329L:
Almost all engine builders will agree that on a naturally aspirated engine, the less load you put on the engine, the faster will be in the car. In turn, that makes them more consistent. In the power adder world, you keep adding power until you get the drive train happy, then figure out a way to tighten it back down, and add more power.

You're confusing the effect of stall early in the run and efficiency late in the run.

Negative, an engine has to be able to accelerate. If the engine doesnt accelerate, it wont run, until shaft speed can catch up. Laying an engine on the converter most the way down the track is NOT the fastest down the track in real bracket racing. It is also not as consistent.

quote:

Originally posted by 329L:

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by 329L:
Almost all engine builders will agree that on a naturally aspirated engine, the less load you put on the engine, the faster will be in the car. In turn, that makes them more consistent. In the power adder world, you keep adding power until you get the drive train happy, then figure out a way to tighten it back down, and add more power.

You're confusing the effect of stall early in the run and efficiency late in the run.

Negative, an engine has to be able to accelerate. If the engine doesnt accelerate, it wont run, until shaft speed can catch up. Laying an engine on the converter most the way down the track is NOT the fastest down the track in real bracket racing. It is also not as consistent.

Ok so according to you, a car with converter slipping 10% 1/4 mile is consistent, but a converter slipping 10% 1/8 mile isn't.

That makes zero sense. It's just what you see in your data that makes you assume it's the only way.

Because you don't know any other way. When I do.

It doesn't matter what distance you go. An inefficient converter early and efficient converter late, is consistent. Look at your 1/4 mile racepak data for evidence. You just don't know how to do it 1/8 mile, when on the other hand I do.

Im assuming you have a power adder?[/QUOTE]

if you count nitrous as a power adder, yes. It's a 650 inch Ford with a couple kits and a powerglide. Consistent enough like that to win a couple divisionals.

quote:

Originally posted by 86BigBlockBird:
Im assuming you have a power adder?

if you count nitrous as a power adder, yes. It's a 650 inch Ford with a couple kits and a powerglide. Consistent enough like that to win a couple divisionals.[/QUOTE]

What is the stall doing with all kits blazing? IM assuming that converter is going north of 6300 with all kits blazing. Also, power adders handle engine load, naturally aspirated stuff does not.

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by Don Higgins Crew Chief Pro Software:
For bracket racing you want high slip ratio in the 1/8th, period. It isn't a pro mod, or 275 radial car that won't repeat from one run to the next. All out performance isn't what wins bracket races.

10% in the quarter is decent, but I would think that most are at, or above that level a few percent.

I asked Jason Lynch, who has won quite a few races, this same question and he told me a few percent doesn't change the MPH much, but can make the car less consistent.

I've won a few Super Pro bracket races myself. More than anyone in the history of Sunshine Dragstrip Clearwater Fl. by a bunch.

Not that night you hit the cone!!!!!!!!!!

quote:

Originally posted by 329L:

quote:

Originally posted by 86BigBlockBird:
Im assuming you have a power adder?

if you count nitrous as a power adder, yes. It's a 650 inch Ford with a couple kits and a powerglide. Consistent enough like that to win a couple divisionals.

What is the stall doing with all kits blazing? IM assuming that converter is going north of 6300 with all kits blazing. Also, power adders handle engine load, naturally aspirated stuff does not.

6700-6800 stall, his converter isn't tight.

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by 329L:

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by 329L:
Almost all engine builders will agree that on a naturally aspirated engine, the less load you put on the engine, the faster will be in the car. In turn, that makes them more consistent. In the power adder world, you keep adding power until you get the drive train happy, then figure out a way to tighten it back down, and add more power.

You're confusing the effect of stall early in the run and efficiency late in the run.

Negative, an engine has to be able to accelerate. If the engine doesnt accelerate, it wont run, until shaft speed can catch up. Laying an engine on the converter most the way down the track is NOT the fastest down the track in real bracket racing. It is also not as consistent.

Ok so according to you, a car with converter slipping 10% 1/4 mile is consistent, but a converter slipping 10% 1/8 mile isn't.

That makes zero sense. It's just what you see in your data that makes you assume it's the only way.

Because you don't know any other way. When I do.

It doesn't matter what distance you go. An inefficient converter early and efficient converter late, is consistent. Look at your 1/4 mile racepak data for evidence. You just don't know how to do it 1/8 mile, when on the other hand I do.

Ive tried many ways sir. Just going off what my customers have said actually works. The way i set stuff up, might be .01-.02 slow from a tighter converter, in mine shaft air. But i promise its faster 90% of the season than by trying to run a tighter converter. Most my customers before buying a spec'd converter from me would see .1-.15 et swing in the 660, after i spec a converter they are seeing .1 at the absolute most. And i am talking about et swing over the entire season! Maybe i just have a different way of skinning a cat boss!

quote:

Originally posted by 329L:
What is the stall doing with all kits blazing? IM assuming that converter is going north of 6300 with all kits blazing. Also, power adders handle engine load, naturally aspirated stuff does not.

It flashes to around 6500-6700. Falls back 900-1000 rpm at the shift.

quote:

Originally posted by 86BigBlockBird:

quote:

Originally posted by 329L:
What is the stall doing with all kits blazing? IM assuming that converter is going north of 6300 with all kits blazing. Also, power adders handle engine load, naturally aspirated stuff does not.

It flashes to around 6500-6700. Falls back 900-1000 rpm at the shift.

The reason it is consistent is because 6500-6700 is getting on the loose side, just like bracket racers like. Yes your converter is going to lock up better on the big end, being built for the power your is making. But that converter is a good bracket converter with the kits blazing.

quote:

Originally posted by 329L:

quote:

Originally posted by 86BigBlockBird:

quote:

Originally posted by 329L:
What is the stall doing with all kits blazing? IM assuming that converter is going north of 6300 with all kits blazing. Also, power adders handle engine load, naturally aspirated stuff does not.

It flashes to around 6500-6700. Falls back 900-1000 rpm at the shift.

The reason it is consistent is because 6500-6700 is getting on the loose side, just like bracket racers like. Yes your converter is going to lock up on the big end because of the driveshaft rpm 1/4 mile. But that converter is a good bracket converter with the kits blazing.

Fixed that for ya boss. To be helpful

It's "tight" at the finish line though, isn't that what we were talking about? my Engine Rpm and Drive shaft RPM are actually the same, 0% slippage (I have the racepak graphs to prove it)

It's basically exactly like Mike said, Loose on the starting line and tight at the finish line...

quote:

Originally posted by 86BigBlockBird:
It's "tight" at the finish line though, isn't that what we were talking about? my Engine Rpm and Drive shaft RPM are actually the same, 0% slippage (I have the racepak graphs to prove it)

It's basically exactly like Mike said, Loose on the starting line and tight at the finish line...

It is, but you have a power adder, and have the power to keep accelerating that converter. Most naturally aspirated stuff does not have the **** your engine has.
There is 2 ways most converter companies build converters, they either use a high stall pump and a higher angle stator in it, or they put a low stall pump and a lower degree stator. The high stall pump and higher degree stator hits harder on the line, couples quicker, but will slip more on big end. The low stall pump/lower degree stator will be loose off the line, and usually is not aggressive off the line, but couples better with driveshaft speed. With all that being said, its 100% based on combination, and the way the customer wants to run an engine.

Hypothetically, if you took a 155mph 1/8 mile dragster with a 3.90 gear and a 34" tire crossing 7000 rpm with the converter slipping 14% which means the drive shaft rpm is 6072 rpm's.

You're saying if you put a 4.30 gear in the same car crossing 7200 with the converter slipping 8%, the car would be slower and more inconsistent 1/8 mile? Or just more inconsistent? Why?