NX Dragster new pistons

torqueofthetown said:
Actually, the most accurate answer would be "it depends"

If both trucks are the same weight and both vehicles have gearing that "optimizes" the power curve of each engine..... the race would be very close if not a dead heat.

the difference being as noted above is that the power curve for diesel engines is a lot closer to "optimum" with street gearing than compared to a gasser that requires a lot of RPM to make good power. A gasser would require a higher stall converter, lower gears, etc. Then a gasser with the same HP would be competitive with a diesel at the track, it just would not have the same good manners on the street that a diesel has.

For example, if you hang a turbo on an otherwise stock gas truck to get 500hp, the gasser would lose in a quarter mile race, swap out the R&P for 4.88 gears and a 3.5k converter and its a whole new ball game.

But thats the beauty of diesel is that you not only can have your cake and eat it too, you can have ice cream on the side... Power, good street manners & better mileage :)
Click to expand...

GM did it with the dmax(310/605) and the 8.1 vortec(340hp/455lb) both ran 5 speed allison and TC to match both motors... yet the diesel was faster at the stripe in stock form..

even with 4.10 gears option for the 8.1 it still isnt faster then diesel.. but you say since the 8.1 has 30 HP more it "should" be faster it even make power at a higher rpm hp peak is 4200rpm on the 8.1

edmunds results from full test of a 01 8.1 2500hd 2wd CCLB
01 2500hd 8.1 340/455
0 - 60 (sec.) 9.2
1/4 mile (sec. @ mph) 17.0 @ 83.9
my 02 lb7 310/520 ran 16.5 @ 85 mph in stock configure at cal speedway in 07
4x4 dmax trucks would dip into the 15s stock..

yet you say the oposite is true.. :what:


greg.. i see your point about shift and the short side not falling into peak torque range... wouldnt increase camshaft duration move everything to the right?
 
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malibu795 said:
GM did it with the dmax(310/605) and the 8.1 vortec(340hp/455lb) both ran 5 speed allison and TC to match both motors... yet the diesel was faster at the stripe in stock form..

even with 4.10 gears option for the 8.1 it still isnt faster then diesel.. but you say since the 8.1 has 30 HP more it "should" be faster it even make power at a higher rpm hp peak is 4200rpm on the 8.1

edmunds results from full test of a 01 8.1 2500hd 2wd CCLB
01 2500hd 8.1 340/455
0 - 60 (sec.) 9.2
1/4 mile (sec. @ mph) 17.0 @ 83.9
my 02 lb7 310/520 ran 16.5 @ 85 mph in stock configure at cal speedway in 07
4x4 dmax trucks would dip into the 15s stock..

yet you say the oposite is true.. :what:


greg.. i see your point about shift and the short side not falling into peak torque range... wouldnt increase camshaft duration move everything to the right?
Click to expand...

We are working hard to improve airflow even more . Greg at ZZ is is making a lot of gains .The cam I did for the Mustang is another huge movement in the right direction . For the dragster we are going to go down that path even farther .

Tommy is getting quite a lot of Dmax’s engine development under his belt now and a shop filling up with diesel work. . The higher we can buzz these motors the less we will burn them up. The only place you can hurt them is to lug them.
John has the ability to tune the torque curve flat making sure not to make more torque then the engine , piston or drive train can take.
In any form of racing from NASCAR to Top fuel , if you lug the engine , you will do damage.


Watch NASCAR drivers who will spin the tires coming out of the pits ,to get up in the power curve , so as not to get a piston from lugging. Tommy Can tell you more about top fuel then any one on the site , after spending many years on Eddie Hills program, if a Fuel motor is ever tugged down below a certain RPM , they toss the short block. As having been over unit loaded
 
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JOHNBOY said:
:hehe::hehe:

The reason the Nitrous was not working or should say not working to the full potentional was the fact that N20 pressure was used to run the shift soleniod. Shifts where programmed into a controller that supplied N20 pressure to the soleniod to shift the trans. The trouble was this setup when enegerized leaked badily. I know. I helped remove it Monday of Dragweek. We thought well know where getting more N20 to the engine that it would run faster. Funny thing was it slowed down. I can remeber the look on Gregs face when I told him more N20 made it slower.:what: The datalog showed clearly the EGTs went down. Ran a back up pass just to see if it would repeat. It did. So I backed the N20 tune up off. Ran another pass and it went quicker.
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All you have just said here is just what I've said all along. The old combination was never tuned with the NOS working! Then you come on here and try to make yourself feel good by saying a new piston design and new combination made more power than the old setup. :hehe::hehe:

You have no idea what worked and what didn't with the old combination just as you have no idea of how to compare the two setups other than the :cheer: and BS your spreading. To say the new is better than the old when you clearly admit things were wrong and then want people to believe the new piston design made more power, and made the car run better. Do you truly thinking people are dumb enough to buy this BS? :badidea:
 
COMP461 said:
Watch NASCAR drivers who will spin the tires coming out of the pits ,to get up in the power curve ,
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Greg

Now you know better than that. The Nascar boys spin the tires as the motors make no power below 4500 RPM. Hell most all of them idle at 2200 - 2500! Try and pull a ~3800 lb car away from a stop and it will stall the motor and they typically have a hard time restarting them. So they Rev them up to make sure as to not stall the motor. It's not going to hurt the piston/rod at all at low speeds as the motors are designed for 8000 - 9000 RPM operation and that's where they make all the power. Since the peak power is up that high the peak torque on them is about 6000 RPM and that is where you would hurt things if the parts are under designed.
 
COMP461 said:
We are working hard to improve airflow even more . Greg at ZZ is is making a lot of gains .The cam I did for the Mustang is another huge movement in the right direction . For the dragster we are going to go down that path even farther .

Tommy is getting quite a lot of Dmax’s engine development under his belt now and a shop filling up with diesel work. . The higher we can buzz these motors the less we will burn them up. The only place you can hurt them is to lug them.
John has the ability to tune the torque curve flat making sure not to make more torque then the engine , piston or drive train can take.
In any form of racing from NASCAR to Top fuel , if you lug the engine , you will do damage.


Watch NASCAR drivers who will spin the tires coming out of the pits ,to get up in the power curve , so as not to get a piston from lugging. Tommy Can tell you more about top fuel then any one on the site , after spending many years on Eddie Hills program, if a Fuel motor is ever tugged down below a certain RPM , they toss the short block. As having been over unit loaded
Click to expand...

i understand how one can hurt an engine by being under or over its said power band with a full load....

cutting power/torque for parts serviability i understand stand as well....

but to say torque means nothing.... i havent firgured out.
 
Diesel Tech said:
Now back onto the pistons. I have a customer that ran a set of cut and coated LBZ cast pistons for 2 1/2 seasons. Made over 100+ hooks on them and pulled it apart and only replace one cause it was dropped during disassemble. He is one of the TOP if not the TOP 2.8" trucks in the country. So they didn't have an easy life and there still going.

Would I do it NO but it's his motor and he chose to do it. So why would a forged piston not last much longer than a season............. none unless the tuning isn't done right! We are not seeing any ring gland collapsing but maybe all of ours are just lucky. The issue is the ring wearing the gland out that we worry about and that is going to happen and we know it.
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What do those boys know about pulling? LOL I remember him whining and bellyaching about having to buy more stock pistons.
 
malibu795 said:
GM did it with the dmax(310/605) and the 8.1 vortec(340hp/455lb) both ran 5 speed allison and TC to match both motors... yet the diesel was faster at the stripe in stock form..

even with 4.10 gears option for the 8.1 it still isnt faster then diesel.. but you say since the 8.1 has 30 HP more it "should" be faster it even make power at a higher rpm hp peak is 4200rpm on the 8.1

edmunds results from full test of a 01 8.1 2500hd 2wd CCLB
01 2500hd 8.1 340/455
0 - 60 (sec.) 9.2
1/4 mile (sec. @ mph) 17.0 @ 83.9
my 02 lb7 310/520 ran 16.5 @ 85 mph in stock configure at cal speedway in 07
4x4 dmax trucks would dip into the 15s stock..

yet you say the oposite is true.. :what:
Click to expand...

You have selective reading skills :D

Of course comparing bone stock diesel to bone stock gas, the diesel would win over the gasser, even Stevie Wonder can see that. My point was that a gasser with the drivetrain optimized for the power curve, it is possible for the gas truck to put up similar numbers to a diesel truck of the same HP.
I'd be willing to bet in your example that if the gasser had 4.88 gears and a looser converter it would more than make up that half a second +/- difference.

:Cheer:

sorry to be off topic.... back to the pistons

its an interesting read
:pop:
 
Gas vs Diesel

I have a 8.1 6 speed man. that runs 15.9 to 16.0. It's bone stock. Traps 88 shifting(easy) like I would like to drive it home. Stock for stock I would take the 8.1 no questions over the early Dmax. If I could get better than a 2.3 60' I think the 8.1 would run mid 15's. It's a EC/LB always full on fuel with everything in it.
 
COMP461 said:
its a little higher then that , but it also depends on which hole its in , they put different compression pistons in each one

the boost is around 45 to 60 psi with 100 to 150 GPM pumps .

the unlimited diesel sled pullers have run aluminum rods for years ,
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No unlimited diesel sledd puller that I know of runs billet aluminum rods. The alcohol tractors do but much lower compression and much less boost than a multiple chargered diesel tractor. They also change the rods after so many pulls. But good luck with it I have toyed with it but I'm very unsure about the aluminum and the compression ratios we run and boost pressures would make some extreme cylinder pressure plus the hammer of combustion it might make for a high maitenance item.
 
The aluminum rod will work in low boost high rpm application , I do not plan on loading the engine below 4500 rpm’s and boost with nitrous will be around 40 psi or less.
The advantage is that a aluminum rod can be made one set at a time , out of billet stock and to a dedicated forging. . I expect 75 to 100 runs on a set of rods , and that is more then a season and at less then a $1000 a set that just part of maintenance .

I have went to great lenghts to get all the weight inside the crank, and get rid of the heavy balancer and flywheel
On a diesel drag racing engine if we are going to go head to head in some of the Gas category’s , especially ones with Pro trees , and auto start . Then the engine will have to get up in a short amount of time , between .5 and 1.5 seconds and leave , cutting a light in the .005 range then low boost and low rotating mass is critical.
I’m building this project , not only to become the fastest , but to also race. I miss going to 12 to 15 races a year and going rounds.
We are also building a program where a Super racers can have a power plant to race with , that will not care about barometric pressure changes , and a turbo diesel engine dose this very well.
.

Curtis has assured me that his rod will match the specs of the aluminum rods with a few hundred grams more weight , so that rod will go in to the production engines
 
I could set up my pressure rig on that engine and tell you exactly how much chamber pressure your making.
 
Stingpuller said:
I have a 8.1 6 speed man. that runs 15.9 to 16.0. It's bone stock. Traps 88 shifting(easy) like I would like to drive it home. Stock for stock I would take the 8.1 no questions over the early Dmax. If I could get better than a 2.3 60' I think the 8.1 would run mid 15's. It's a EC/LB always full on fuel with everything in it.
Click to expand...

4x4 run faster on treaded tires then a compare able 2wd truck of roughly same power :poke:
 
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