ok now, seanvicious I found a place that does dynos and I think thats around the same price. I have $280 in my bank account and my rent is $200. i have empty tanks and waiting to hear if I got the job tomorrow, so there is my dilemma and the fact that headers will be a grandma Christmas present, BUT!!!!!!P.S. i live in Spokane, WA

GET THIS! I found that Friday night Spokane Speedway is holding Streetracing Drags. Since this is the last night of the season they aren't doing the hands as flags like the old days fridays, but are doing the Christmas tree with time slips and all. GET THIS! it only cost $5 to either go or watch. (it's a get kids off the street kinda price)

everyone pray that it doesn't rain and I will take my truck this Friday. I will try to get 2-3 runs in and maybe 4, but no more than that unless the numbers get lower and lower. I have raced before so I should get consistant times. I will only run off Chevron Diesel since its kindof an average diesel, not the best, but not the worst. I will run it regular. No trying to get anything free. Just running bone stock. Then I will go and get the truck weighed and we can compute some numbers. If i get the headers as a gift or something then we can all see how good they are with real 1/4 mile times and maybe some dyno runs.

again please pray that it doesn't rain.

 

Sounds like a plan there 2New2Fords. Kinda' what I planned on doing myself.

Dave7.3, I don't know if your comment was made tongue-in-cheek or not, but assuming it wasn't, let me explain. Nothing mechanical can achieve a 100% perfect transfer of energy or motion. Bearings may roll smoothly, but they still have some friction. When one gear turns another a little bit of the energy of the force turning the driving gear is lost to friction of the teeth of the two gears rubbing against each other as they mesh and unmesh (and therefore that energy doesn't get transferred to the driven gear). This is especially true when the shafts of the gears are a 90* angles to each other - like in your differentials.

When a shaft spins inside a seal there is a little bit of friction between the seal and the shaft. Even when a shaft spins in oil - especially thick gear oil - the oil itself creates a little bit of drag that opposes the spinning motion of the shaft. All of these are examples of the drivetrain loss we're talking about. Add up the little bit of friction loss at each point, then realize that all these frictional losses exist in the tranny, in the differential, and the axles, and it adds up to use up around 15%-30% of your engine's total power just to keep things turning.

That is the drivetrain loss we're discussing. It has to be taken into consideration when using vehicle mass and acceleration to try to calculate HP output of the engine at the flywheel - as opposed to HP output at the wheels.

 

CheeperJeeper, that comment was made with good intentions. I do know that you cannot achieve perfect effiencicy in a drivetrain system. I know of all the friction and power loss as descibed but I do not agree with a 25-30% loss as mentioned earlier. Maybe under certain conditions, say with a Transfer case and an auxilary overdrive. Stock drive train loss in theory should be around 15% to 20% depending on 2wd or 4wd systems. Alot also depends on the transmission type. There is a difference in automatic and manual transmission drivetrain loss, 4speed and 4speed OD loss, and the rear gearing etc. I am basically stating that trying to slap a general drivetrain loss of 25% is incorrect. The factors that make up the drive system should determine the drivetrain loss. I also hope that your comment was made with good intentions CheeperJeeper. I ask that you do not make such a comment implying that I am oblivious to the system and construction of a working vehicle. Thank you.

 

I am also aware that no vehicle is indestructable. Ford has their quirks and so do chevy, dodge, etc. I just tend to stick to Ford as I have seen alot of their vehicles last many years. My family has also owned alot of different vehicles but the Ford was always the one that took a beating and came back for more. Our Fords were still running like a top even after 10-12 years. I know there are alot of other brands out there that have been holding their own but I still like my old Ford...

 

Sorry Dave, I didn't notice your "Senior User" tag. I read your comment to be questioning what drivetrain loss was. Obviously I misread you. No need to get upset. I wasn't trying to call you out - quite the opposite - I was trying to be helpful.

Although you obviously understand, there may be users on the forum who may not have, and hopefully one or more will read my long-winded explanation and gain something from it.

If you read my earlier posts in the thread I said essentially the same thing you just did. I even pointed out that the calculator seanvicious linked STATED an assumed 18% loss - which may or may not be valid. Though it is right in the ballpark of your estimate of 15%-20%. The actual assumed DL factor wasn't stated for the calculator that KJLYPW posted a link for. The previous number of 25% you mentioned isn't my number - it is a calculation seanvicious did based on 260 flywheel HP & 196 rear wheel HP as quoted in an article he read about a particular turbo kit. Assuming that the flywheel and rear wheel HP numbers in the article were accurate, then that would be the approximate DL for that truck - though not necessarily for any other truck.

Like you, I also said that an assumed DL factor may or may not be correct for a given vehicle. I even went a little further to say that if it is off, it renders a single calculation worthless. It will still work as a guage for how much you get out of a mod - but only if you do both before & after calcs. Even then it only shows the degree of improvement - the actual calculated number can't be relied upon. I imagine you would also agree, eh?

 

CheeperJeeper, I agree with ya. Sorry if I started off a little heated but after reading back through the posts I realized you and I were on the same page the whole time . The calculator that was posted is not completely accurate but it is a good estimate of hp at the rear wheels as ya said. Might be a great tool to monitor performance by one upgrade at a time instead of all at once.

 

That's my plan man! Though I'll probably use the one seanvicious posted since it's DL factor is stated up front and falls within the range of your expert estimate

Actually I'll probably punch my numbers into both of them - just to compare the results. I'm especially interested in punching my first set of stock numbers into the one seanvicious posted and see how close it gets to nailing the original factory flywheel HP rating. That should give us a pretty good indication of how accurate the 18% assumed DL really is.......

As for the misunderstanding, no hard feelings here - nor there from the sound of it. 'Sall good.....

 

Hey guys, just to keep things in perspective. The specs for HP/Torque numbers listed on the engine are generated from a fresh new engine. Not ones that has 150k+ miles on them. Even though this is nothing for a diesel, there is still wear and tear on them not to mention all the other parts that go along for the ride. If you really want to know the effectiveness of your money and sweat, the baseline dyno test as to where the truck is now in 2006 is a great place to start if you really want to know what your truck is putting out, just don't be surprised if the numbers come out lower than brand new out of the box.

 

Yup, or for those of us too cheap to spend the $ to put it on a dyno, doing a baseline 1/4 mile run & calculation on the unmodified stock truck, then doing it again after each of the mods should be about the next-best thing.

Another thing to consider is that since the original dyno numbers were most likely developed from an average of results done on a bunch of "tight" new engines, you may very well will still get just as good of numbers (possibly even better) after 150k - because the frictional losses in the rings, bearings, cam lobes, rocker arms, etc. will be less on an engine that is well broken in and "looser". Assuming that your compression is good, your fuel system is clean & up to snuff, and it is running correctly, of course.

Just a thought.....

 

You guys spend to much time theorizing and not enough doing- get er done- have some fun, lifes to short- just do what makes you happy!!! PS I love my truck and tinkering, and I love all the BS on this web site too.

 

Guess you missed the threads where I explained that

1) I bought my truck without my wife's knowledge and it is currently stashed at a buddy's house. I already had 9 rigs and agreed not to buy another until I sold one. Then I found a deal on this one I just couldn't pass up. Fortunately it looks like my old Chevy is sold so I will get to bring the Ford home soon. So far I've only managed to sneak off to go over there and work on it twice - so up to this point hanging out here and learning about it is about all I've been able to do.

2) I'm an engineer and a cheap SOB so I analyze things every which way before doing anything in order to maximize the bang for my buck. Good thing too - otherwise I would have already replaced a $400 IP and still have a truck that doesn't run worth a damn. Instead, by investing the time to learn every possible thing that could cause my problem - from you guys - I figured out (with youe guys help) that I could simply change the timing of my IP 180* - in about the same amount of time it would take to replace a pump - and have a truck that runs pretty decent.

Besides, I AM having fun and doing what makes me happy - learning tons about something I know nothing about (diesels) and applying it to get something good out of it - a better performing truck! Looks like I get to spend at least a few hours with my new baby tomorrow. No performance mods yet - but I'll wager it will be running better 24 hours from now. THAT'S what I call fun!

 

update on the drag races.

bad news and good news.

bad news is that I wont be able to go tomorrow to the races since I just got hired to work friday nights, sat, and sunday. I got a job here in spokane finally and it should pay pretty well for a part timer.

good news is, that when I start making some dough and make sure next years tuition and rent is payed for I might dyno and or race before and after headers(if I can afford them)

sorry, but no race. unless the tow truck I will be driving doesnt get done being painted till saturday, then just maybe.
more bad news though is that my truck doesnt want to start as easy every time. fixing it is in the works...

back to the headers subject!

 

Well just for laughs, I've had these headers on for 2 weeks now, and though I drive it every day, I dont put on a lot of milage. So far it looks like in my normal driving around town milage, its increased from about 15.5 to around 17.4, but thats roughly speaking with only about 1/2 tank worth of driving.