NX Dragster new pistons

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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I think every one can appreciate the quest for a lighter bob weight, but those tiny pins freak me out.
 
Joesixpack said:
I think every one can appreciate the quest for a lighter bob weight, but those tiny pins freak me out.
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I know what you mean, but the pins are holding up so far.
They are a 100 grams lighter then a stock pin. Another aspect of the smaller pin is a stronger piston. This is what the piston engineers asked for to make the piston stronger.
These pistons are heavy now , and this weight will come down as we get farther in to the program.
The crank is lighter because of the reduced throw diameter. as well. .
The goal is two fold ,
first stabilizing the rotating assembly , the weight that is hung on the front and rear of the crank causes a lot of stress on the front and rear main web. I wound not even think about doing this to a street truck. Second, in a drag race application, the motor needs to accelerate “REV GAIN “ the first gear ramp will be in the 1000 rpm per second range .
This is one of the reasons that power in a 7000 lbs truck doesn’t always work the same as power in a 1900 lbs dragster. The rate of acceleration is so great that the load runs away from the motor.
To answer a question on gas vs. diesel, a 500 hp engine will run just as fast at the same weight if both set ups are optimized. The reason is that to optimize a gas engine of 500 hp to run correctly in a 7000 truck, the gearing , and converter requirements would make it unlivable on the street.

The CR engine , not just the Dmax is going to go thru a lot of advancements in the next year or so. People like us and others are going to push the enlovope in direction we know have worked in the past on other engine programs,. It is not I mportant whether it’s a gas or diesel power plant , its all the same. Some of what we do will not work as well as we expect, but here is a saying

If you do what you’ve always done ,
You’ll get what you’ve always got.
 
torqueofthetown said:
JFC..... its just a reference to one of the funniest and most popular sitcoms ever.... don't get your lederhosen in such a knot

http://www.youtube.com/watch?v=lgC7z_vR78U&feature=related
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Thanks. I dont watch much TV. I have watched maybe two complete episodes of that show.
Soup Nazi said:
Yeah, I was given the name. LOL. Im proud of it and it fits somewhat.

Just try and get the top secret parts and products out of us. Your results will most likely be very similar to the poor guy who had his soup taken back.
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Don I apoligze for my rant. I misunderstood the meaning behind it the name. Still do not care for it.
nwpadmax said:
How about this....can you please explain this to me more?

What do you mean by "less timing" to "make it run"?

Are we talking a few degrees? Because that could be explained by engine-to-engine differences...you know...pin locations, gear accuracy, absolute cam timing, etc., all that.

Or are we talking more?

What other factors could be contributing to that? How about injectors?
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Good question. You and I both now that build tlorance can cause Actual TDC to differ from computed TDC. That is very real. But in that case you can add or subtract the entire table to correct for this. That is not the case with the Mustang vs. Z28. The Z28 needs more timing in the higher RPMs to run. The difference between the two is more than I have ever seen as a build tolerance issue. Secondly thev Z28 likes less timing down low. When you look at idle per say. The Z28 likes a stock timing at warm idle. Happiest at about -1. The Mustang does not not like that at all. Much happier at +3. Some of that I beleive is the difference between the pistons. The idle timing is interesting. The stuff I have read about the re- entrant talks about how they work in a low speed emissions scenrio. Just using the data I have I thing that the re-enterant design deffinately is idles and is happeir below 2000 rpm because the better siwerl ad slow piston speeds. But we dont run the Mustang anywhere near there at the track. That is why the the different bowl design was chosen. Tommy did not look at this as a diesel he looked at as a race engine. Used what he knew worked on the high boost race engines he has built. I honestly went in skeptical and came out with a different point of veiw.

The injectors at the time where the same according to Brady at II. The pulsewidths back that up. The Z28 now has larger injectors to combat the extra timing.

Diesel Tech said:
This is all great BS as anyone trying to compare a part that it's only purpose in life is to last for about 3 minutes total use, is not going to be for the average diesel owner. There is a real good reason the Top Fuel people ALL toss the pistons, pins and rods in the trash after 10 passes event when they still look good. Most of the time they do not make it that long! The Top Alcoholic racers run them about 25 passes then they go in the trash.

If Greg plans to rebuild this motor just as a top fuel car does it might work. The base material chosen for a top fuel application isn't something I would event worry about in a street driven diesel application. What Greg has to worry about is that his application is much heavier (internal engine) than a Top Fuel application so it just may jump up and bite him in the a$$ if he tries to run them time and time again.
As for the Mustang it has not done one thing better than it did last year with a set of stock cut pistons in it! Those are the facts as the car runs the same times as before and until it does much better than before this is just more wishful thinking. So if your going to change the tires and the car setup it had better be a whole bunch quicker and faster than it was before otherwise it's just more of the same.
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Reply to the part in blue. He is not asuming an infinate life of the parts. The pistons and rods will only be in the engine for so many passes then removed. This is a race engine and race parts. I may have missed it but I dont think Greg ever said these where Street truck parts. So that banter is pointless. The dragster will be towed to the lane and back from the topend to the pits. Only under its own power on the track. No street use there.


As for the facts in Red

Facts straight of Hot Rod Magazines website

2008
Mike Wood 1994 Mustang

Best ET and MPH at DragWeek 08
9.9100 138.2200

Average at Dragweek 08
10.3264 132.05

2009
Mike Wood 1994 Red Mustang

Best ET and MPH at DragWeek 09
9.7170 147.8800

Average at Dragweek 08
10.0845 141.0880

So the difference from Dragweek 2008 to 2009 is nothing?:hehe:

It went faster at the Texas Mile to in 09. :woohoo:
 
Small pins are good for short burst of power as long as they get changed often. I do not believe the smaller pin make the piston or rod area any stronger as it's smaller diameter puts more load in a smaller area, than the larger pin does. So all you have done is moved the issue. For durability the larger pin is the way to go but if you plan to rebuild and replace every 20 runs or so then lot's can and should change.

How many of you are willing to rebuild and replace your engine every 20 passes or so?

Johnboy

So you are trying to tell use that after having the car together for over a year and learning from the first year that it ran a best of

Best ET and MPH at DragWeek 09
9.7170 147.8800

versus

Best ET and MPH at DragWeek 08
9.9100 138.2200

As for the rest of your numbers you left off the very important part that the owner of the car and owner of NX Nitrous Systems could not event figure out that in a week of driving and racing the NOS did not work until the last race! Kind of screws up all the BS numbers that were from one year to the next doesn't it! LOL

Better to include all of the facts just not some of them to support the BS being spread here.
 
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Diesel Tech said:
Small pins are good for short burst of power as long as they get changed often. I do not believe the smaller pin make the piston or rod area any stronger as it's smaller diameter puts more load in a smaller area, than the larger pin does. So all you have done is moved the issue. For durability the larger pin is the way to go but if you plan to rebuild and replace every 20 runs or so then lot's can and should change.

How many of you are willing to rebuild and replace your engine every 20 passes or so?
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Even with big Pins the pistons are the weak point. As things are now your best to replace your pistons after every season.

I doubt they will stay in a full season in the dragster. Dyno passes will eat up a lot of there life span. I bet Tommy will have to remove and replace them at least two times in 2010.
 
Forrest Nearing said:
are we talking about gas vs. diesel here? :confused:

or are we talking about getting a diesel down the track as quick as possible? :confused:
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im talking about comps "torque means nothing" statement

a 500rwhp gas has about ~500-600lb
a 500rwhp diesel has about ~900-1100lb

hence why the diesel truck WILL BE faster then a gas truck.. of same weight.

but as comp said torque means nothing... right???

more TQ you have the faster you can get something done.

i dont know why you wouldnt want torque...
 
JOHNBOY said:
Even with big Pins the pistons are the weak point. As things are now your best to replace your pistons after every season.

I doubt they will stay in a full season in the dragster. Dyno passes will eat up a lot of there life span. I bet Tommy will have to remove and replace them at least two times in 2010.
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Well I have never had nor heard of a piston failure in a Duramax that was caused by the pin area of the piston so it cannot be very weak. The fact that were running low 9's in a 6000 lb truck with the larger pin and piston assemble without issue is one of the reasons just to leave it alone.
 
malibu795 said:
im talking about comps "torque means nothing" statement

a 500rwhp gas has about ~500-600lb
a 500rwhp diesel has about ~900-1100lb

hence why the diesel truck WILL BE faster then a gas truck.. of same weight.

but as comp said torque means nothing... right???

more TQ you have the faster you can get something done.

i dont know why you wouldnt want torque...
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the more HORSEPOWER you have, the faster you can get something done... horsepower is a measure of torque vs. speed.

the point is, we're not talking about gassers... we're talking about diesels... a diesel is going to make more torque than you need, so who cares about torque in a diesel if you're trying to drag race!??!?!? :confused:

horsepower wins drag races... if torque was king, then my old 12v that did 535/1196 would surely outrun an 800hp Duramax that only makes 1100ftlbs, right? :rolleyes:
 
Diesel Tech said:
Well I have never had nor heard of a piston failure in a Duramax that was caused by the pin area of the piston so it cannot be very weak. The fact that were running low 9's in a 6000 lb truck with the larger pin and piston assemble without issue is one of the reasons just to leave it alone.
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Then if you have never had a pin area failure there might be some margin there strenght wise you can use. Would I put a small pin piston in a 6000 lbs truck that during a pass drops see rpm as low as 3000 after a shift? No I would not. But in a car that ways less then half that and during a pass never drops below 4000rpm. Would I? Yes. It has worked in the Mustang so far with out issue.

The main reason to replace a forged piston after ever season in they get weak. The ring grooves start to collapse and the crown starts.

The pistons in my truck look fine after the 09 season. They will not be used in 2010.
 
malibu795 said:
im talking about comps "torque means nothing" statement

a 500rwhp gas has about ~500-600lb
a 500rwhp diesel has about ~900-1100lb

hence why the diesel truck WILL BE faster then a gas truck.. of same weight.

but as comp said torque means nothing... right???

more TQ you have the faster you can get something done.

i dont know why you wouldnt want torque...
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its not that we don't want it , we just run the engine so far above peak torque. The engine will leave the live at around 4500 to 4700 and never dip below that rpm.

i
 
Diesel Tech said:
Johnboy

So you are trying to tell use that after having the car together for over a year and learning from the first year that it ran a best of

Best ET and MPH at DragWeek 09
9.7170 147.8800

versus

Best ET and MPH at DragWeek 08
9.9100 138.2200

As for the rest of your numbers you left off the very important part that the owner of the car and owner of NX Nitrous Systems could not event figure out that in a week of driving and racing the NOS did not work until the last race! Kind of screws up all the BS numbers that were from one year to the next doesn't it! LOL

Better to include all of the facts just not some of them to support the BS being spread here.
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Engine wise completely different setup. Remember those feable Bosch electronics we use. Chassis setup was the same. Same tires. Race weight was almost 200lbs heavier.


The Nitrous not working is a funny story. Depends on who you talk to on that one. Mike tells a different story about it.

So we where just spraying the heck out of it then? Far from the truth.

But you cant explain away the FACT it went quicker and faster in 09.:owned:

You could call Mike and ask him if he wants to switch back .
 
All You need to do is read the articles about the car in 08 challenge and MIKE was quoted on the fact the NOS did not work until the last race! If you look around the internet you will find where he has said the same thing, so who's telling a story now! :owned: The facts are real simple here the car had a year + of development, with NOS that works and it didn't do any better than the year before unless you call a first NOS pass of 9.91 against a year of development and NOS tuning to a 9.71 a gain.:owned:

The car runs fine but there is and was no real gains made from switching out the old combination to the new one but if you believe the BS and :cheer: trying to be spread here you would think it was a major improvement but the facts just do not support that! LOL

As for asking Mike about switching back that's not an option, since he burned up the old combination and never offered to pay for it then took the engine to Tommy and disassembled it to see what was in it. Then had the balls to ship it back in pieces without all the pieces being there! That's is someone I'm glad I never dealt with and will be very careful with if I ever did.
 
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malibu795 said:
im talking about comps "torque means nothing" statement

a 500rwhp gas has about ~500-600lb
a 500rwhp diesel has about ~900-1100lb

hence why the diesel truck WILL BE faster then a gas truck.. of same weight.

but as comp said torque means nothing... right???

more TQ you have the faster you can get something done.

i dont know why you wouldnt want torque...
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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 :)
 
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.
 
Just a couple of observations:

I think whatever happened to the '08 motor and who did what and what got shipped to who in however many pieces is not really relevant to this piston discussion (although it may be appropriate for douchebag awards in a different forum).

OK, if we say ET has much to do with traction and whatnot that I really don't care about, then we should be talking MPH.

MPH went from 138 to 148. I'm sure it feels faster and I'm not downing anything but the math says it's 6.5% faster / has 6.5% more power. Like if you were at 800 HP before, it's 852 HP now.

To attribute that to the bowl alone is tough but may be true.

I guess where I struggle the most with the bowl design is that in a gasser you have a mostly homogeneous charge lit off by the plug. That seems to me, to be a million miles away from the stratified charge coming from our injector into the hot, dense air in the diesel bowl.

So I am keeping my mind open on the bowl thing. On the one hand we would give a lot for 6.5% more mojo. On the other hand maybe that can be made up elsewhere. Dunno!
 
Diesel Tech said:
All You need to do is read the articles about the car in 08 challenge and MIKE was quoted on the fact the NOS did not work until the last race! If you look around the internet you will find where he has said the same thing, so who's telling a story now! :owned: The facts are real simple here the car had a year + of development, with NOS that works and it didn't do any better than the year before unless you call a first NOS pass of 9.91 against a year of development and NOS tuning to a 9.71 a gain.:owned:

The car runs fine but there is and was no real gains made from switching out the old combination to the new one but if you believe the BS and :cheer: trying to be spread here you would think it was a major improvement but the facts just do not support that! LOL

As for asking Mike about switching back that's not an option, since he burned up the old combination and never offered to pay for it then took the engine to Tommy and disassembled it to see what was in it. Then had the balls to ship it back in pieces without all the pieces being there! That's is someone I'm glad I never dealt with and will be very careful with if I ever did.
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I HIGHLY doubt that Mike called nitrous oxide "NOS" like some dumbass ricer :rolleyes:
 
nwpadmax said:
MPH went from 138 to 148. I'm sure it feels faster and I'm not downing anything but the math says it's 6.5% faster / has 6.5% more power. Like if you were at 800 HP before, it's 852 HP now.

To attribute that to the bowl alone is tough but may be true.
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While the car did run more MPH one will never know what the old combination was good for since it never got the :nos: setup working and dialed in. So trying to compare the 2 is just trying to make oneself feel good about what was done.
 
Diesel Tech said:
All You need to do is read the articles about the car in 08 challenge and MIKE was quoted on the fact the NOS did not work until the last race! If you look around the internet you will find where he has said the same thing, so who's telling a story now! :owned: The facts are real simple here the car had a year + of development, with NOS that works and it didn't do any better than the year before unless you call a first NOS pass of 9.91 against a year of development and NOS tuning to a 9.71 a gain.:owned:
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: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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