not guess the hp but guess the ET??

[289nate]

What rings on the pistons? Did I miss that? The rings will make all the difference in how much power the vacuum pump in worth. Have run an Aerospace pump with thick old school rings. Not worth it due to the drag of the pump and the rings not needing help. It will keep your oil cleaner for a longer period. I just suggest testing without it IF your rings were not picked with a vacuum pump in mind.

Picking a killer ring set based on a vacuum pump will be worth real power. Friction thing.

There are also much better vacuum pumps than the Aerospace. Star Machine and a purpose built piston and ring set is my next choice. GZ motorsports is also in the running.

[86_regal]

I just don't understand why the "more torque" or "peak torque" rhetoric persists when talking about drag racing...?

If torque BY ITSELF were so important, why isn't every track and sanctioned race class in the country FLOODED with cars with Cats, Cummins & Detroit diesels with 1000lb 16 speed transmissions and two speed dump truck rear ends?

Why did everyone in drag racing go in the opposite direction, with the revitalization of the powerglide, HIGHER stall speed converters and MORE RPM?

Only the guys that caught on did.. Apparently some here still have no idea. You don't see 2500 rpm formula 1 cars

Apologies for the delay

Certainly, application is of paramount importance.

Regarding TC selection for a street/strip car, there's a bit of subjectivity involved. The converters I put in cars I've driven on the street were/would be intolerable to others BUT we're amazed I could get my "junkyard" big block car 10.80s (which compared to most on this site isn't very impressive). Others' street/strip cars who thought their car was fast that I've driven I KNEW I could get at LEAST .6-.7 lower with a converter change ALONE. It's important to mention this IF we're talking about that type of application. But this thread is NOT what we're talking about. This IS a class sanctioned RACING APPLICATION.

I'm just an enthusiast who lurks here most of the time just to learn as there some very bright people on this site, but I find it amazing there is STILL such fervor over the torque vs. HP debate (which is largely what the debate over TC selection in this thread comes down to).

Anyone who's spent 10-15 mins at class race event will, or at least should, QUICKLY recognize there isn't going to be a single car there running less than (dare I even go this low) 5K RPM during a pass IF they're competitive.

The debate has been settled, and certainly not by me... HP WINS RACES. That said, gear and converter your car around HP... NOT torque.

To the OP,
This might seem off topic to you, but I assure you it's relevant. Posts about specing a convertor for your car to utilize more low end torque is counterproductive.

[86_regal]

I just don't understand why the "more torque" or "peak torque" rhetoric persists when talking about drag racing...?

If torque BY ITSELF were so important, why isn't every track and sanctioned race class in the country FLOODED with cars with Cats, Cummins & Detroit diesels with 1000lb 16 speed transmissions and two speed dump truck rear ends?

Why did everyone in drag racing go in the opposite direction, with the revitalization of the powerglide, HIGHER stall speed converters and MORE RPM?

On a well developed engine you will have good ft/lb per cube numbers even if the engine operates well about peak tq, the better the average is a above peak then the better the shift recovery will be.

Trans and rear ends or a balance between weight, efficiency and ratio to keep it in the rpm range needed not to mention cost, most fast power adder drag cars make to much tq so more gear or gears do not help, prostock on the other hand are running 6 speeds now I believe and would run 7 if possible but they are operating well above peak and trying to target about a 1500 rpm curve so the engine doesn't bog.

The pro turbo diesel cars run more gears to keep the rpm down, maybe Linco's?

In most classes that allow turbo diesel there are competitive examples as well as dominant ones, in the Daytona 24 hour Proto Type Class I think it was Audi that dominated it a cpl years with one that was only turning around 4700 rpm if I recall, since then others have tryed.

There are not a lot of people in the industry with the knowledge or pocket book to pursue it.

The "Top Diesel" class at the NHRDA World Finals is the absolute fastest and most powerful diesel powered racecars on Earth! These guys show up prepared to never lift until they cross the finish line...typically at over 200MPH. https://www.youtube.com/watch?v=ygbVUEn_mHc

Mazda's SKYACTIV Technology helped its all-new Clean Diesel-powered sports racing prototype go wheel-to-wheel with some of the world's fastest sports cars at Daytona International Speedway, as they tackled the grueling demands of the 52nd Rolex 24 at Daytona. https://www.youtube.com/watch?v=NylmcEoFtos

Your response has me confused...

At a glance, it would seem you're trying to build a case to disagree. Reading your post more thoroughly, multiple times gives me a completely different message. Such as, one of the examples has nothing to do with drag racing and the other, which does, are highly boosted, turbocharged diesels (the FASTEST diesels in the WORLD) running 6's?

Which is it? You do agree that generally MORE HP, RPM and therefore higher stall convertors lower ET or not?

I've read a few of your posts on here and there's no question you're a bright person with what appears to be more racing/engine building experience than I have along with a strong fervor for motor sports. With all due respect, many of your posts could interpreted as adversarial and argumentative.

I'm not sure where that comes from as a don't spend a ton of time on ST, particularly as of late because it's become a bit "cliquey" and adversarial in general. I am hoping things will start going in the other direction as there is still much valuable information on this site.

[user-17438]

I just don't understand why the "more torque" or "peak torque" rhetoric persists when talking about drag racing...?

If torque BY ITSELF were so important, why isn't every track and sanctioned race class in the country FLOODED with cars with Cats, Cummins & Detroit diesels with 1000lb 16 speed transmissions and two speed dump truck rear ends?

Why did everyone in drag racing go in the opposite direction, with the revitalization of the powerglide, HIGHER stall speed converters and MORE RPM?

Only the guys that caught on did.. Apparently some here still have no idea. You don't see 2500 rpm formula 1 cars

Apologies for the delay

Certainly, application is of paramount importance.

Regarding TC selection for a street/strip car, there's a bit of subjectivity involved. The converters I put in cars I've driven on the street were/would be intolerable to others BUT we're amazed I could get my "junkyard" big block car 10.80s (which compared to most on this site isn't very impressive). Others' street/strip cars who thought their car was fast that I've driven I KNEW I could get at LEAST .6-.7 lower with a converter change ALONE. It's important to mention this IF we're talking about that type of application. But this thread is NOT what we're talking about. This IS a class sanctioned RACING APPLICATION.

I'm just an enthusiast who lurks here most of the time just to learn as there some very bright people on this site, but I find it amazing there is STILL such fervor over the torque vs. HP debate (which is largely what the debate over TC selection in this thread comes down to).

Anyone who's spent 10-15 mins at class race event will, or at least should, QUICKLY recognize there isn't going to be a single car there running less than (dare I even go this low) 5K RPM during a pass IF they're competitive.

The debate has been settled, and certainly not by me... HP WINS RACES. That said, gear and converter your car around HP... NOT torque.

To the OP,
This might seem off topic to you, but I assure you it's relevant. Posts about specing a convertor for your car to utilize more low end torque is counterproductive.

I have a stock eliminator customer. I built engines for his super gas, and top dragster before he decided to try stock eliminator. I built the engine and it was a turd because he chose the wrong converter. Just because the engine made peak power low, he chose a damn near street converter. I ordered him up a converter that was 400rpm lower than peak horsepower, and now he's over a second under index. When he had a hard time running just below.

Why was it so much faster even though it blows past peak torque?

[6.50camaro]

Because the engine stays in such a narrow rpm range just below and just above peak HP you have input more average HP to the converter over the run . Then if the converter is designed right it will aply more average horsepower to the rest of the drivetrain. Just my thoughts on it. Dan

[GARY C]

I just don't understand why the "more torque" or "peak torque" rhetoric persists when talking about drag racing...?

If torque BY ITSELF were so important, why isn't every track and sanctioned race class in the country FLOODED with cars with Cats, Cummins & Detroit diesels with 1000lb 16 speed transmissions and two speed dump truck rear ends?

Why did everyone in drag racing go in the opposite direction, with the revitalization of the powerglide, HIGHER stall speed converters and MORE RPM?

On a well developed engine you will have good ft/lb per cube numbers even if the engine operates well about peak tq, the better the average is a above peak then the better the shift recovery will be.

Trans and rear ends or a balance between weight, efficiency and ratio to keep it in the rpm range needed not to mention cost, most fast power adder drag cars make to much tq so more gear or gears do not help, prostock on the other hand are running 6 speeds now I believe and would run 7 if possible but they are operating well above peak and trying to target about a 1500 rpm curve so the engine doesn't bog.

The pro turbo diesel cars run more gears to keep the rpm down, maybe Linco's?

In most classes that allow turbo diesel there are competitive examples as well as dominant ones, in the Daytona 24 hour Proto Type Class I think it was Audi that dominated it a cpl years with one that was only turning around 4700 rpm if I recall, since then others have tryed.

There are not a lot of people in the industry with the knowledge or pocket book to pursue it.

The "Top Diesel" class at the NHRDA World Finals is the absolute fastest and most powerful diesel powered racecars on Earth! These guys show up prepared to never lift until they cross the finish line...typically at over 200MPH. https://www.youtube.com/watch?v=ygbVUEn_mHc

Mazda's SKYACTIV Technology helped its all-new Clean Diesel-powered sports racing prototype go wheel-to-wheel with some of the world's fastest sports cars at Daytona International Speedway, as they tackled the grueling demands of the 52nd Rolex 24 at Daytona. https://www.youtube.com/watch?v=NylmcEoFtos

Your response has me confused...

At a glance, it would seem you're trying to build a case to disagree. Reading your post more thoroughly, multiple times gives me a completely different message. Such as, one of the examples has nothing to do with drag racing and the other, which does, are highly boosted, turbocharged diesels (the FASTEST diesels in the WORLD) running 6's?

Which is it? You do agree that generally MORE HP, RPM and therefore higher stall convertors lower ET or not?

I've read a few of your posts on here and there's no question you're a bright person with what appears to be more racing/engine building experience than I have along with a strong fervor for motor sports. With all due respect, many of your posts could interpreted as adversarial and argumentative.

I'm not sure where that comes from as a don't spend a ton of time on ST, particularly as of late because it's become a bit "cliquey" and adversarial in general. I am hoping things will start going in the other direction as there is still much valuable information on this site.

Just a response to your post, sorry if I offended you.

[AMXstocker1]

What rings on the pistons? Did I miss that? The rings will make all the difference in how much power the vacuum pump in worth. Have run an Aerospace pump with thick old school rings. Not worth it due to the drag of the pump and the rings not needing help. It will keep your oil cleaner for a longer period. I just suggest testing without it IF your rings were not picked with a vacuum pump in mind.

Picking a killer ring set based on a vacuum pump will be worth real power. Friction thing.

There are also much better vacuum pumps than the Aerospace. Star Machine and a purpose built piston and ring set is my next choice. GZ motorsports is also in the running.

rings are low tension 3mm .043 .043

[AMXstocker1]

I wouldn't worry about excessive exhaust duration just yet. The less lift on the exhaust makes sense and the split in duration makes sense compared to what a few cam grinders are doing now. Opening and closing events are important to pull it off. I'd sort it out before changing a thing.

Why would I be working on a "gas" engine for the strip when I could just build my Duramax hauler? Turbo on methonal? Top fuel on nitro? The beauty of diesel in an endurance race is the ability to make the same power using less fuel. Not all out acceleration.

were not changing anything its getting new head gaskets and were going through the fuel system to see if theres a reason it was lean carb builder said it should've been more than enought fuel. but anyway we have a connection at a shop with a hub dyno and 02 so were going to take it and make a couple pulls and make sure everything is ok and then we have a race on october 6th if we don't find a test and tune before then.