Dr.Buick
09-08-2011, 07:34 AM
Talked to Kenny Duttweiler last night to start another engine build for my wifes car a TA performance Aluminum Block And heads build. Everytime I talk to him I learn more and more. I brought up Murray's Lotus and we taked about imports and what's out now! he sent me a artical that he wrote a couple years ago I thought I would post. ENJOY
First Person - Kenny Dutt Weiler
Turbo Tuning Pioneer, Engine Builder Extraordinaire
From the July, 2005 issue of Turbo & High-Tech Performance
|
http://static.turbomagazine.com/_SiteConfigs/_global/images/no_photo_100px.gif (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/photo_01.html)
It was a good timing thing. I opened the doors here in 1984 and I was in one of the early issues of Turbo. The car was an 1986 Buick and we did a back half exhaust, we got 13 horsepower and at the time I didn't think about of it. It was more noise but it definitely picked up some power. That spawned all the 2.5-inch conventional muffler stuff. It became an industry. Borla was the first one to come out with a back half setup.
After that we were generating a lot of information on the Buick. There weren't a whole lot of turbo cars (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) out in 1986 that had a magazine based around them. Turbo magazine worked out really good for me because we ran an ad in the back of the magazine for several years and that little ad did its job. We swapped out the text and stuff featuring our intercooler necks and gaskets and so on. We had guys calling to order 40 gaskets at a time.
I remember worrying that we made more cast necks than there were intercoolers out there. Ten years ago I thought I better not order anymore of those. It's probably going to be a dead duck and I would end up with 100 intercooler necks laying around. The Buick thing just keeps going on and on. The neck is 30 hp and a pound and half difference in boost; nothing to sneeze at for sure.
Break Through Technologies
The single biggest advancement without a doubt was factory electronic fuel injection. From that point on injection has been an integral part of turbocharging. The diesel industry spawned better turbos because when we came into it in the mid 1980s we were dealing with 20-year old turbo technology-T04Bs and the like; pretty crude by today's standards. But believe it or not, diesel trucks (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) then the small car industry and motorsports drove the quality of the product to the next level.
Aftermarket stand-alone engine management has come a long way from the early days when a tuning computer had two knobs; one for spark control and one for fuel.
Now high-end Motecs have so much technology that they can surpass your ability to even figure what you can do with what you have; a way more powerful tool than you can use. This, however, is much better than having expectations that go beyond the technology of the unit. There were times in the early days when in your mind you had what you needed but in the computer's mind it wasn't going to play the game. We were able to tune in our heads where the computer could not get to. It was frustrating at times but that's the cost of being right on the leading edge of something. Pushing the boundaries of technology leaves a lot of broken parts in your wake.
Everything you know about race engines applies to turbo engines. We started off with expecting the turbo to the bulk of the work. Build the engine as good as possible and have the turbo feed that engine. The power levels have escalated. We started off our first big number was 600 hp. We hit it with a nitrous set up, dynoed it at 600 horsepower and thought that was a real big deal. Today I have customers out there running 1,600 horsepower, 191 mph through a '87 Regal.
The key to tuning is evolution; making things better; bigger camshafts, bigger bore, some times more compression. And we have gotten a little bit smarter about it too. There are some really interesting things that happen when you play with bore and stroke, rod ratio and that sort of thing. It's relevant to how you build a turbo engine. Going from three hp per cubic inch to six, seven, eight hp per inch is saying a lot. The reliability today is far greater than we had when we were making half the horsepower.
Gasket technology is something that most people would look right past but gaskets are key when it comes to reliability. We could do no better than the components available to us to use. Back then there were no "turbo pistons" we had to change the design to make it work in our world.
Connecting rods were never strong enough but they were made stronger, stronger and stronger until they would not bend when we threw boost at them.
Ring technology today is quite good, the oils we run through the engines are superior, valvetrain components are spinning faster. Yep, evolution of hardware and, today, evolution of software as well makes it all possible.
Best First Mods
Without changing anything on the engine I would definitely start on the exhaust. Backpressure is the enemy of any turbo engine. So anything you can do downstream of the turbo is going be an improvement. Downpipe, cat and exhaust system should all be looked at. Increasing the intake efficiency should be next. After that, a reasonable bump in boost.
This all goes back to how we approached the Buick but the issues we addressed are transferable to most any turbo engine. It was almost as if we sat down and wrote out a script.
In like 1987 we put a 62-1 turbo on Ron Fruchey's Buick, a really large turbo in those days. We put bigger injectors on it; 62 lb/hr or whatever it was. Built a huge intercooler by taking an HKS core and fabbing up some end tanks. We went out to Palmdale and went 128 mph and thought man we hit a home run. Like it was the end of the world.
But it was all about evolving. Every time we evolved the turbo, decreased backpressure, increased the air coming into the engine we were winning. The key was addressing the fuel side, which was easy on the Turbo 6.
With today's cars you need the ability to get inside the ECU to realize any substantial power gains. It's harder to jack up the fuel pressure because of the ECU as well as the deadhead fuel systems they are running today. So when you change injectors you now have to be able to recalibrate the ECU.
Rookie Mistakes
Believing that boost is power. It can be the most misleading thing you can look at because boost is gauge pressure. Gauge pressure is 90 psi of air in a truck (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) tire, 90 psi of air in a bicycle tire. The differences in the amount of air between the two is huge, however the "pressure' is the same. It is the amount, or volume, of air that opens the door to more power not the pressure of the air or the number on the gauge.
Camshafts can be problematic. Enthusiasts can make mistakes in cam timing, especially in a lightly modified street-driven vehicles that don't require much of a cam change. Also overlap is much different in naturally aspirated engines compared to turbo engines.
The biggest single mistake enthusiasts make period is trying to run too much boost on pump gas. The single easiest improvement they can make when they start to overboost is to up the quality of the fuel. We had an engine that just touched 600 hp on pump gas, it made high 700s on 100-octane and 900 on race gas.
In a rush to make more power, many forget that fuel is a huge variable; and it can vary from tank to tank. Even pump gas can have an anti-knock value of 88 octane on one tank and 91 on the next.
You can make a naturally aspirated engine detonate to a degree and it hurts nothing. But you pass the detonation threshold with a turbo engine and you can kill it quick. High cylinder pressures and detonation won't mix for long.
Turbos are great devices for screwing things up because a little is good and little bit more is better and pretty soon you're in trouble. Alcohol injection is a good cheat when approaching the detonation threshold and it can make a lot of sense for street cars.
On Imports
It's a neat deal in a lot of ways. Those four-valve engines are better suited to turbochargers than your conventional two-valve head stuff. They make more horsepower per cubic inch and the impressive thing is that they are all small displacement.
Small-displacement engines make more power per inch than big engines. Getting 1,600 hp out of a 3.0-liter is straightforward but to expect to do that out of a 500-inch V8 (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) isn't going to happen. You run out of breathing capacity, you run out of friction, you have none of the inherent gifts of DOHC engines.
I am working on a 3.5-liter inline six right now. It's an FJ Land Cruiser 1FZE block that is going to Titan Motorsports. It's a physically large hulk and were going short stroke, big bore and aiming for 1,700 or so.
The challenge here is fuel. This thing has an appetite that goes beyond my comprehension but we're going to prove we can feed it more fuel than it can burn. Considering it takes 2.5 times as much alcohol to make the same power as gasoline we had to re-fit how we measure the fuel on the dyno.
We have a nice manifold to try with it. It comes down to unconventionally conventional thinking. We tried some exotic 2JZ stuff but are using the industrial-looking truck-like FJ head. It's been ported of course, but the valves are 3 to 4mm larger than a 2JZ and the ports are bigger than a 2JZ and that's going to be big. The camshafts are massive, huge lobes just plain big. We had to have the cams made from scratch-not many 1,700-horse FJs out there.
There's no difference in thinking or my approach when it comes to import vs. domestic engines because the end goal is always the same: burn as much a fuel as the engine can physically withstand.
I do extensive calculations on combustion pressure because there are some rules of physics you have adhere to. One of the biggies is how much cylinder pressure can you make before things start to scatter.
Of course, the ability to control exhaust temperatures and taking into account the type of fuel are considerations. Alcohol is a little more forgiving than gasoline, especially in the exhaust gas temperature area. Alcohol is good for and extra 400 to 500 degrees which gives you a little breathing room.
Centrally located spark plugs means you can run less timing lead. A DOHC engine flows a lot more air at low lift so how you cam those engine is a little bit different than a two-valve. Also, the fact that imports make more power per cylinder affects the header design; you want larger diameter runners to expedite flow.
I have been looking at some of the stuff I am doing on the four-valvers and applying it to the two-valve stuff and it seems to be working well. So there is more crossover than one may expect.
The interesting thing on the sport compact stuff is they are using castings that are every compromising because they were built with light weight not necessarily strength in mind. The Focus engine is a 1,200cc engine pushed too far, poor crankshaft, worse rods no over-engineering.
On the opposite side the Supra engine is incredibly stout, true it is a more serious engine; more of a Chevy (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) small-block mentality. They are making 1500 plus on a stock crank swinging aftermarket rods and pistons. Do some headwork and get the tune right and you're off. It is extremely impressive. Also, the Subaru and Mitsubishi Evo engines are really good.
The Future
We need a hard-hitting "common denominator" engine. A really good engine that will have a good life span; it can't disappear after three or four years. It has to be accessible and receptive to modification. And most of all, the aftermarket has to hop on the bandwagon. Right now I am playing with the LS1 V8 and I am getting a factory blown Ecotec Cobalt SS engine to play with and things look quite promising on paper.
Read more: http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#ixzz1XMbTVKH4
First Person - Kenny Dutt Weiler
Turbo Tuning Pioneer, Engine Builder Extraordinaire
From the July, 2005 issue of Turbo & High-Tech Performance
|
http://static.turbomagazine.com/_SiteConfigs/_global/images/no_photo_100px.gif (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/photo_01.html)
It was a good timing thing. I opened the doors here in 1984 and I was in one of the early issues of Turbo. The car was an 1986 Buick and we did a back half exhaust, we got 13 horsepower and at the time I didn't think about of it. It was more noise but it definitely picked up some power. That spawned all the 2.5-inch conventional muffler stuff. It became an industry. Borla was the first one to come out with a back half setup.
After that we were generating a lot of information on the Buick. There weren't a whole lot of turbo cars (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) out in 1986 that had a magazine based around them. Turbo magazine worked out really good for me because we ran an ad in the back of the magazine for several years and that little ad did its job. We swapped out the text and stuff featuring our intercooler necks and gaskets and so on. We had guys calling to order 40 gaskets at a time.
I remember worrying that we made more cast necks than there were intercoolers out there. Ten years ago I thought I better not order anymore of those. It's probably going to be a dead duck and I would end up with 100 intercooler necks laying around. The Buick thing just keeps going on and on. The neck is 30 hp and a pound and half difference in boost; nothing to sneeze at for sure.
Break Through Technologies
The single biggest advancement without a doubt was factory electronic fuel injection. From that point on injection has been an integral part of turbocharging. The diesel industry spawned better turbos because when we came into it in the mid 1980s we were dealing with 20-year old turbo technology-T04Bs and the like; pretty crude by today's standards. But believe it or not, diesel trucks (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) then the small car industry and motorsports drove the quality of the product to the next level.
Aftermarket stand-alone engine management has come a long way from the early days when a tuning computer had two knobs; one for spark control and one for fuel.
Now high-end Motecs have so much technology that they can surpass your ability to even figure what you can do with what you have; a way more powerful tool than you can use. This, however, is much better than having expectations that go beyond the technology of the unit. There were times in the early days when in your mind you had what you needed but in the computer's mind it wasn't going to play the game. We were able to tune in our heads where the computer could not get to. It was frustrating at times but that's the cost of being right on the leading edge of something. Pushing the boundaries of technology leaves a lot of broken parts in your wake.
Everything you know about race engines applies to turbo engines. We started off with expecting the turbo to the bulk of the work. Build the engine as good as possible and have the turbo feed that engine. The power levels have escalated. We started off our first big number was 600 hp. We hit it with a nitrous set up, dynoed it at 600 horsepower and thought that was a real big deal. Today I have customers out there running 1,600 horsepower, 191 mph through a '87 Regal.
The key to tuning is evolution; making things better; bigger camshafts, bigger bore, some times more compression. And we have gotten a little bit smarter about it too. There are some really interesting things that happen when you play with bore and stroke, rod ratio and that sort of thing. It's relevant to how you build a turbo engine. Going from three hp per cubic inch to six, seven, eight hp per inch is saying a lot. The reliability today is far greater than we had when we were making half the horsepower.
Gasket technology is something that most people would look right past but gaskets are key when it comes to reliability. We could do no better than the components available to us to use. Back then there were no "turbo pistons" we had to change the design to make it work in our world.
Connecting rods were never strong enough but they were made stronger, stronger and stronger until they would not bend when we threw boost at them.
Ring technology today is quite good, the oils we run through the engines are superior, valvetrain components are spinning faster. Yep, evolution of hardware and, today, evolution of software as well makes it all possible.
Best First Mods
Without changing anything on the engine I would definitely start on the exhaust. Backpressure is the enemy of any turbo engine. So anything you can do downstream of the turbo is going be an improvement. Downpipe, cat and exhaust system should all be looked at. Increasing the intake efficiency should be next. After that, a reasonable bump in boost.
This all goes back to how we approached the Buick but the issues we addressed are transferable to most any turbo engine. It was almost as if we sat down and wrote out a script.
In like 1987 we put a 62-1 turbo on Ron Fruchey's Buick, a really large turbo in those days. We put bigger injectors on it; 62 lb/hr or whatever it was. Built a huge intercooler by taking an HKS core and fabbing up some end tanks. We went out to Palmdale and went 128 mph and thought man we hit a home run. Like it was the end of the world.
But it was all about evolving. Every time we evolved the turbo, decreased backpressure, increased the air coming into the engine we were winning. The key was addressing the fuel side, which was easy on the Turbo 6.
With today's cars you need the ability to get inside the ECU to realize any substantial power gains. It's harder to jack up the fuel pressure because of the ECU as well as the deadhead fuel systems they are running today. So when you change injectors you now have to be able to recalibrate the ECU.
Rookie Mistakes
Believing that boost is power. It can be the most misleading thing you can look at because boost is gauge pressure. Gauge pressure is 90 psi of air in a truck (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) tire, 90 psi of air in a bicycle tire. The differences in the amount of air between the two is huge, however the "pressure' is the same. It is the amount, or volume, of air that opens the door to more power not the pressure of the air or the number on the gauge.
Camshafts can be problematic. Enthusiasts can make mistakes in cam timing, especially in a lightly modified street-driven vehicles that don't require much of a cam change. Also overlap is much different in naturally aspirated engines compared to turbo engines.
The biggest single mistake enthusiasts make period is trying to run too much boost on pump gas. The single easiest improvement they can make when they start to overboost is to up the quality of the fuel. We had an engine that just touched 600 hp on pump gas, it made high 700s on 100-octane and 900 on race gas.
In a rush to make more power, many forget that fuel is a huge variable; and it can vary from tank to tank. Even pump gas can have an anti-knock value of 88 octane on one tank and 91 on the next.
You can make a naturally aspirated engine detonate to a degree and it hurts nothing. But you pass the detonation threshold with a turbo engine and you can kill it quick. High cylinder pressures and detonation won't mix for long.
Turbos are great devices for screwing things up because a little is good and little bit more is better and pretty soon you're in trouble. Alcohol injection is a good cheat when approaching the detonation threshold and it can make a lot of sense for street cars.
On Imports
It's a neat deal in a lot of ways. Those four-valve engines are better suited to turbochargers than your conventional two-valve head stuff. They make more horsepower per cubic inch and the impressive thing is that they are all small displacement.
Small-displacement engines make more power per inch than big engines. Getting 1,600 hp out of a 3.0-liter is straightforward but to expect to do that out of a 500-inch V8 (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) isn't going to happen. You run out of breathing capacity, you run out of friction, you have none of the inherent gifts of DOHC engines.
I am working on a 3.5-liter inline six right now. It's an FJ Land Cruiser 1FZE block that is going to Titan Motorsports. It's a physically large hulk and were going short stroke, big bore and aiming for 1,700 or so.
The challenge here is fuel. This thing has an appetite that goes beyond my comprehension but we're going to prove we can feed it more fuel than it can burn. Considering it takes 2.5 times as much alcohol to make the same power as gasoline we had to re-fit how we measure the fuel on the dyno.
We have a nice manifold to try with it. It comes down to unconventionally conventional thinking. We tried some exotic 2JZ stuff but are using the industrial-looking truck-like FJ head. It's been ported of course, but the valves are 3 to 4mm larger than a 2JZ and the ports are bigger than a 2JZ and that's going to be big. The camshafts are massive, huge lobes just plain big. We had to have the cams made from scratch-not many 1,700-horse FJs out there.
There's no difference in thinking or my approach when it comes to import vs. domestic engines because the end goal is always the same: burn as much a fuel as the engine can physically withstand.
I do extensive calculations on combustion pressure because there are some rules of physics you have adhere to. One of the biggies is how much cylinder pressure can you make before things start to scatter.
Of course, the ability to control exhaust temperatures and taking into account the type of fuel are considerations. Alcohol is a little more forgiving than gasoline, especially in the exhaust gas temperature area. Alcohol is good for and extra 400 to 500 degrees which gives you a little breathing room.
Centrally located spark plugs means you can run less timing lead. A DOHC engine flows a lot more air at low lift so how you cam those engine is a little bit different than a two-valve. Also, the fact that imports make more power per cylinder affects the header design; you want larger diameter runners to expedite flow.
I have been looking at some of the stuff I am doing on the four-valvers and applying it to the two-valve stuff and it seems to be working well. So there is more crossover than one may expect.
The interesting thing on the sport compact stuff is they are using castings that are every compromising because they were built with light weight not necessarily strength in mind. The Focus engine is a 1,200cc engine pushed too far, poor crankshaft, worse rods no over-engineering.
On the opposite side the Supra engine is incredibly stout, true it is a more serious engine; more of a Chevy (http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#) small-block mentality. They are making 1500 plus on a stock crank swinging aftermarket rods and pistons. Do some headwork and get the tune right and you're off. It is extremely impressive. Also, the Subaru and Mitsubishi Evo engines are really good.
The Future
We need a hard-hitting "common denominator" engine. A really good engine that will have a good life span; it can't disappear after three or four years. It has to be accessible and receptive to modification. And most of all, the aftermarket has to hop on the bandwagon. Right now I am playing with the LS1 V8 and I am getting a factory blown Ecotec Cobalt SS engine to play with and things look quite promising on paper.
Read more: http://www.turbomagazine.com/includes/turp_0507_kenny_dutt_weiler_turbo_tuner/viewall.html#ixzz1XMbTVKH4