I've been pouring over threads here for over a week now trying to decide what vehicle I want to buy and there's something I just don't get.

Looking at the tuning results from the sponsor of this section, 5 Star Tuning, the dyno graphs posted on his website show two '05 V10 auto's, before and after.

One looks to make around 255rwhp and 325rwtq
The other makes around 248rwhp and 300rwtq

The 255/325 has an aftermarket intake and exhaust.

These are 93octane tunes.

I don't know the nice way to say this, but that's it???

And I say that because I see 4.6 Mustangs get N/A tunes with minor bolt-ons and make almost the same amount of power.

MPH just tuned one and made 256/294. It was an '03 Mustang GT
Another '01 GT made 267/303.

I could go on but you see what I'm talking about. These 4.6 2V V8 cars made about the same power as the 6.8 3V V10 trucks. Sure, these cars had CAI's, exhaust, or maybe some other minor bolt-ons, but no heads/cams, or anything major. Only thing I can think of is the auto tranny in the V10 vs. the manual in the V8. Is that the difference? Does it eat that much damn power? Is there any tuning results of MANUAL V10's out there? The truck is rated at 362hp/457tq from the factory and these are making 250hp/300-325tq at the rear WITH a tune?

I'm beginning to think I could get an F150 with a 4.6 and tow my car as well as an F250 with a V10. Can someone tell me what I'm missing?

2.2 more liters, two more cylinders, and that's it???

Sorry, I'm not bashing the V10, I see too many people on here raving about it, I'm sure I'm overlookoing something or whatever. Someone want to enlighten me

Thanks

Ken

 

Well the biggest thing I can tell you that makes a difference between the V8s and the V10 is that the big ten makes its power down low whereas the eights have to rev to make their power. So in terms of easy towing the ten is better because you don't have to rev the **** out of it to make the torque you need.

 

I just traded in a 2004 F150 5.4L for my V10. The F150 had electric fans, U/D pullies, CAI, cat-back exhaust, and a tuner. It was making over 250rwhp before the pullies and fans. Still no comparison to the stock V10 when towing. I think it was the tranny just sucking all the life out of the engine. I hate automatics.

 

What you're forgetting is quite a bit of inertial mass.

MUCH heavier transmission. Driveshaft. Rear gears. Axles. Tires/rims.

That leads to a much higher degree of parasitic power loss, as well as the way a rear-wheel dyno reads "power", all leads to much lower numbers are the rear wheels than you are accustomed to.

 

There's got to be something else. 361hp/457tq rated at the engine from the factory, add a custom tune, and you end up with 250hp/300tq at the rear wheels. It looks like he picked up 30-40 tq/hp with tuning. That makes it close to 400hp/500tq, but it's only showing 250hp/300tq.

That would mean it's taking close to 200tq and 150hp to turn the drivetrain/wheels. That just doesn't sound right. We're talking 35+% drivetrain loss.

Are my numbers wrong? I haven't been drinking today...lol

Maybe 5 Star Tuning or someone else has some numbers from a 6-speed manual that's been dyno'd and/or tuned.

 

I have the 3 valve V10 backed by a hand shaker, I too would like to see some dyno numbers from 5 Star with that combo!

From what I read a year or so back, the Ford auto tranny has a bit more parsitic loss than a GM or Dodge auto tranny.

Enjoy,
RustyFuryIII

 

Agreed. Every aspect of the rest of the driveline is going to have more loss than a mustang or F150. Transmission is way more heavy duty, transfer case, driveshaft (I bet ya my driveshaft in my new 350 has to be 3X the weight of my 150), huge 10.5" axles... and dont forget the larger trucks are naturally tuned a bit lower peak more broader and more power down lower. Thats why the peak numbers dont mean a whole lot.

Its also not that accurate to compare exact numbers between different dynos on different days...

There were some years the 460 big block was rated down to 200hp and 350#at the flywheel mind you... and that was fords strongest motor at the time...

 

It is not a race car engine, it is for hauling big heavy loads and pulling a 3.5 ton truck around. It sure feels good driving it.

 

Drivetrain loss is well over 30%. A beefy drivetrain will suck more power than a light duty drivetrain. You also got to remember while their are gains in HP and tq with tuning a good bit of power to the wheels comes from just tuning the trans. Locking up the TQ in the right areas can do a lot for putting power to the ground which makes it seem like the engine is putting out quite a bit more power.

 

Most (all?) rear-wheel dynos in use today use a fixed weight drum, and calculate HP based on how fast the vehicle can spin up that drum.

Anything that limits the acceleration of that drum will show as a lower HP number. So ANY weight in the drivetrain WILL show up as a "loss" of HP on a rear-wheel-dyno.

An aluminum driveshaft in a Mustang will show up as a HP "gain" on the dyno. Does it effect the actualy flywheel numbers? Heck no. But it shows up on the dyno.

After HP is calculated, torque is calculated using the engines RPM at any given point. The "torque" on a rear-wheel dyno is doubly interpolated.

Also, the V10 has a heavy crankshaft, which also makes that "HP" number low on the rear-wheel-dyno. Again, does it effect how much torque is coming out the back of the crankshaft? Heck no.

AND - the V10 is setup for "torque" not it's ability to spin up fast. Timing has a lot to do with that, and you'll see the dyno numbers increase a lot just by a timing tweak. Doesn't really increase the flywheel torque a lot, but it makes those dyno numbers look VERY good in comparison.

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The above explanation of the rear-wheel-dyno numbers also shows why people think electric fans save them some power. They don't. They just make the dyno numbers look better. Do they actually save any power? Nope, there's no such thing as a free lunch. However, it allows the engine to spin up slightly faster, making the dyno numbers look a little better.

Of course, the real-world test is in the pudding. Mike's 87 octane tune got me from 10 second 0-60 down to 9.02-9.04 second 0-60. A 10% reduction in time. That's HUGE. (a combination of power AND shifting).

 

I'm not exactly sure what your trying to teach me about howrsepower and torque, but power is power. Anything you can do to reduce the amount of power it takes to move your car and/or anything you can do to increase power AT the rear wheels is a good thing.

A simple example...the rear wheels. When I went from (on my Mustang) 17X8 wheels with 245/45 tires to 17X10.5 wheels and 315/35 tires, I noticed the difference. The wheels were heavier, the tires were heavier, thus it took more power to turn them. If I were to make back to back dyno runs, a pull with the lighter wheels and then a pull with the heavier wheels the power numbers would've been less with the heavier wheels. It took more power to turn the heavier wheels, leaving less power to turn spin the wheel on the dyno.

Same thing applies to water pumps, electric fans, aluminum flywheels/driveshafts, etc. While I'm not a big believer in all these things being massive power savers like the adds always boast, the do save a little power. And the less the engine has to work to turn everything on the car, the more power it has to move the car.

You ever drove some little four banger and "felt" the A/C kick on? That's horsepower been zapped by the A/C compresser. A/C compressor kicks on, engine has to start turning it, it takes power to do this, less power now at the wheels.

I don't know why you mention the crankshaft, being part of the engine, I would assume the HP/TQ rating given by Ford would include the power it takes to turn the crankshaft.

Back to these V10's, I still find it hard to believe that it takes that much power to move the rear wheels. But if it is, it is, I'm far from an expert on any of this, expecially these big trucks and V10's.

I keep thinking to myself though...people are towing 15,000 pounds around, on top of the 7000 pounds the vehicle itself weighs, that's 20,000+pounds, with around 250rwhp and 300rwtq,...BUT...it takes 150rwhp and 200rwtq just to turn the drivetrain

This next statement may be way off but, in my way of thinking (which can be quite illogical sometimes) that's like saying spinning the drivetrain on these trucks is the equivelant of moving around 8,000 pounds. Make sense?

I think I'll just buy another 4.6 Mustang, weld on a class4 hitch, throw some airbags in the rear coil cprings, put a 4.10 gear in the rearend, and pull my Mustang with a Mustang

 

You know, in theory, the instant a light bulb is switched on, it draws an infinite amount of power, although it draws it for an infinitisamally small amount of time. But anyway, the "infinite power" business gets your attention, at least until you notice that the household power meter doesn't even hicup when the light is turned on.....

Evidently the number one selling "truck" for the last thirty or forty years is the Ford F-series , and of course the superduties with their beefed up chassis and brakes, etc., are rated for the greatest loads.

The thing is, you can put a 5.4l Triton in either an F-150, or an F-350, just depending upon what feels right to you. If you want to pull a mustang with a mustang, go for it.

Personally, comparing what you can do in theory, with what is done in practice, the "practice" approach typically works better.

 

Compared to my '02 F150 5.4l, towing our 7k TT with my V10 is...well there is no comparison Towing experience is better in every situation I can imagine, including power. I couldn't imagine that truck with a 4.6l - would have been awful trying to town our TT. Bear in mind I am referring to the older gen of motors - no experience with the 3v 5.4 and 4.6. I love this truck and its V10 powertrain.

I don't have Mike's tuner (yet) but there is always Xmas coming up in 5 months!!!!

-CC

 

Your truck is similar to one I'm very interested in. Basic XL supercab, V10, 6-speed, 2WD, regular bed. No bells and whistles, I don't need them. I'd like power windows and locks but I can't find a truck in my price range that includes them, is still 2WD, and a 6-speed. They become XLT's and 4WD's with auto tranny's or they are $50K It's got A/C and C/C, that's good enough.

I'll still get one of these big guys, as I said, I'm not bashing it, I'm just amazed that that it takes that much power to get one of them moving. No wonder the MPG's are terrible in them.

I'm not sure how the light bulb thing pertains to this topic, but I didn't know that about the light bulb, so thanks for sharing that

 

BTW, the shop that tunes my Mustang is having a dyno day in August. I should have a V10 by then, a 6-speed manual version, and I'll get him to put it on the dyno and see what it does. I'm sure he could actually tune it also and I'll see if he's running a special during that weekend and how much it would cost. Probably around $200-$250. The Mustang get's all my "mod money" and it might get jealous if I spend any on the F250 but we'll see
Hopefully not too many N/A 4.6 2V Mustangs will put up better numbers than me