Billet Aluminum Cylinder head

Top fuel TQ and HP can only be estimated, no engine or chasis dyno has ever recorded accual #'s that i know or heard of.

Estimates i've seen were between 6000-8000lbs of TQ And same with HP
If they run in the RPM band of 8000-8500 then TQ would be lower i would think.

According to the math these engines eather make more HP than stated, or they make less TQ than stated, or the RPM peak is off quite a bit, honestly i think it's the RPM peak that's off.

Nitromethan is a hard fuel to light and it's a long burning fuel(like diesel), so IMO it would have to have a lower Peak RPM to work properly.

I think that 7000-7500 rpm @ peak HP is about as close to accurate as you can get.
 
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yeah the 7500 rpm peak was a complete guess but i know they dont run near the cam a prostock does and 8500 supposed to be a common shift point so i figured peak would be close to 1000 below.

if they are making peak at 7500 and making 8000 hp they would be around 5600 ftlbs. I would venture to say the diesel super semis are making or exceding that.
 
gotta12v said:
yeah the 7500 rpm peak was a complete guess but i know they dont run near the cam a prostock does and 8500 supposed to be a common shift point so i figured peak would be close to 1000 below.

if they are making peak at 7500 and making 8000 hp they would be around 5600 ftlbs. I would venture to say the diesel super semis are making or exceding that.
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It's possible, but im not so sure. according to the math the diesels make much less TQ at a 5500-6000 peak RPM HP. Those diesels get several runs out of a set of bearings, Top fuel dont hardly get one run on a set of bearings, Cylinder psi is so high it boggles the mind.

When you can after one run smash the best bearings money can buy your doing something! :lolly:
 
talk to any diesel superstock guy they are smashing the wrist pin bushings flat on a rod with a 1.625 pinbushing in only a couple pulls. 4 charger 3 stage will make some cylinder pressure.

also they are operating in a much lower rpm range so the hp is not there but the tq most certainly is. an 1150ci k series cummins engine with 4 chargers running under 4500 is gonna make some torque
 
gotta12v said:
talk to any diesel superstock guy they are smashing the wrist pin bushings flat on a rod with a 1.625 pinbushing in only a couple pulls. 4 charger 3 stage will make some cylinder pressure.

also they are operating in a much lower rpm range so the hp is not there but the tq most certainly is. an 1150ci k series cummins engine with 4 chargers running under 4500 is gonna make some torque
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Understandable, Those engines (diesel) last for 30 seconds each pull they make 3-4 pulls(30 seconds each) then rebuild that's 2 minutes of run time.

Top fuel makes exactly 4.5 seconds under full power and HAS to rebuild.

The diesel engine last's 26.6 times longer than the Top fuel engine....before rebuild is needed.

Sure those diesel's are impressive, but lets face it. Not much of a comparison there. IMO

Not to mention the diesel has three times the size/weight in parts and a ton more boost, so in reality it should be breaking down more. but it's not.
Reason is that the cylinder psi's are not close to what Top fuel is period!

Top fuel has been recorded to 16,000 psi

Diesel Have never exceded 9,000psi To my knowledge. personally i have seen mid to upper 5k's but never more!
 
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Interesting discussion. I have an aluminum rod from a Top Fuel dragster I picked up at Nationals two years ago or so that was marked "7 runs" on it and you can see where the rod started to mushroom out under the wristpin.

Now if I could just get 5 more, do alittle machining, and viola have a nice set of aluminum rods for my puller for about $300...

I wonder how close the measurements are? (hmmmmm)
 
snedge should be able to give us the rod journal od on a k series cummins

diesel supers run main girdles and deckplates that have bolts to tie the whole block together if not they will blow in half. they smash the best wrist pins available flat using a much larger od pin than a fuel car. they turn slow and make huge torque compared to a spark engine. the piston is compressing 300 psi manifold pressure on the 4 charger setups.
 
imagine what a top fuel engine would do if they were allowed to run more than 45 psi boost?

300psi would be sick!

one other thing to consider is the materials used in the availible cummins size bearings and the V series top fuel stuff. Strength to weight ratio favors the top fuel engine by a pretty nice margine about 50%, cummins bearings will be bigger yes, but the material is about half as strong, so we are back to square one, with how many runs one can make before rebuild. i've been told that the backing plate of the new berings is made from a tool steel strength material...but was not told exactly what it was.
 
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whats the current allowable nitro percentage 80%? theres alot of limits on what they can do, so im sure alot more hp could be made but would the components handle any more and could the cars hook anymore hp thats the question
 
gotta12v said:
whats the current allowable nitro percentage 80%? theres alot of limits on what they can do, so im sure alot more hp could be made but would the components handle any more and could the cars hook anymore hp thats the question
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Very true, another thing i thought of is "What if" You were allowed to use nitrous ....:rockwoot:

That would be interesting for both the top diesels and the top fuel cars...


80-90% nitro% i believe is the limit.
 
DIESEL_POWER said:
...but the material is about half as strong, so we are back to square one, with how many runs one can make before rebuild. i've been told that the backing plate of the new berings is made from a tool steel strength material...but was not told exactly what it was.
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Wade, what is the latest and greatest main bearing material?

At the street/strip level you hear a lot of guys talking about King aluminum bearings but I've never seen anyone comment on TF bearing materials.
 
nwpadmax said:
Wade, what is the latest and greatest main bearing material?

At the street/strip level you hear a lot of guys talking about King aluminum bearings but I've never seen anyone comment on TF bearing materials.
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Im not sure about the aluminum, honestly i have never used them, nore have i seen them used.

TF bearings i know are not aluminum, they are some hard type of steel bearing, just not sure exactly what type.

i'll visit Samakow in a few weeks and i'll find out more then.
 
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if top fuel pressures are so high, what are they doing to keep the pressure in?
and why do we have such a hard time at lower pressures. (gasket failure)
just a question
 
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