I hope it checks out. I might even use the aluminum block with the nv4500. I think that gearing would be much better, and it would let me do the towing if I wanted to. I think a cammed 5.3 would be good enough to tow with, and It would take most of that block weight difference and put it slightly lower and farther back. I think I'm in the minority on here for people who like to be able to take turns faster more than straight lines.

 

Expecting 100# off the front to make any discernible difference in corning is silly and I think you know this.

For a heavy vehicle, especially one that will tow, more cubes is always the better choice.

IMO, sell the alum 5.3 block and invest that in money in other aspects of your project. If the block checks out, you can sell it for some good coin

 

 

Ok ok ok ok, internet you crack me up. Go home, you're drunk

This EXACT argument got me banned from the Corvette forum, lmao. Lets see if I can help you guys out, without suffering a similar fate

A) reducing weight to improve handling is somewhat a myth
B) 100lbs off the front axle of a truck that is already traction limited in the rear will be negligible, but its a free country and your money! Live your best life
C) Stick around and find out why
D) Im an *******, but this is not a personal attack on anyone, if someone gets offended here..... well science > opinion

A) "Handling" is often a term used to describe peak grip, or peak cornering G forces generated. This is actually a function of the tires, but the tires have a second element to them; weight. Traction comes from weight pressing the tires into the ground. This is why air pressure is so important, it changes the contact patch and also why lighter cars run lower pressures to keep the tire conformal to the surface. "BuT wHaT aBoUt RaCe CaRs?!?!" you ask? Great question! What race cars lack in static weight they make up for in downforce. Which has the function of......... YOU GUESSED IT!!! ADDING WEIGHT. So lets get to the real meat and potatoes here; reducing weight to improve handling is actually supposed to be "reducing weight to improve transfer and transition response" Because the vehicle/suspension/tires have to work less to move that weight

So lets close that point with saying the truck in question will generate greater traction with the iron motor because it will have more weight pressing the tires into the ground and therefore more traction

Now, another point; reducing the weight on the front axle will allow the truck to transition quicker from left to right and has the function of effectively stiffening the suspension and roll bar rate. Have I lost any students yet?


B) 100lbs, while not insignificant is also not very significant when talking about a vehicle that already scales at 4000lbs. But anyone reading this can go out and test this for themselves. Get your biggest buddy. Get your buddy's wife. Hire the biggest person you can find; roll them into your passenger seat if you have to. Go whip on it. Beat the every living **** out of your truck. You will find that 1) you feel no difference in ultimate G generation 2) you will still be out driving your tires

C) The book "Race Car Vehicle Dynamics" and automotive engineering courses are great resources if you're ever bored or sentenced to life in prison and need something to do

D) I have 2 cars that will out corner anything in this thread. Both run on 4 cylinders, but only 1 is supposed too Both have iron block, aluminum head engines. One in the front, the other has it in the rear

Any questions?

PS: closing point- I think the OP should build the engine he is happy with, both are an upgrade to what he hates about his truck, but without tire/suspension/brake upgrades its silly to say the reason for the aluminum motor is to improve handling. It wont. It will actually be worse (according to the agreed upon understanding of the term "handling"), mathematically; but the difference is negligible in this case

 

Great post, but I'm a little disappointed

You mentioned the weight is over the front wheels but not how HIGH the weight is. This isn't a corvette where the weight is touching the ground, it is significantly higher which would change his roll center

I still agree with what I said and what you said, I just expect you to put a little more emphasis on the location of the weight

 

The CG of the motor should be ~ the height of the cam center line. Comparing a truck to a Corvette, yes; huge delta. Absolutely yuuuuuge

But comparing the CG delta of an iron motor to an aluminum motor while still in a truck chassis, I am putting money on it being a <1% change, but we would have to do the math to determine that. I would like to explore that however, so I am not just spouting drivel and fake news

 

Let's do our due diligence and we'll circle back

 

I have an aluminum block I can weigh. I need to source an iron one. Real numbers are worth it, if we are going to the effort. All the peripherals truck to truck weight the same, so its just block/ piston/ rod we need to weigh

And I need to crack open some text books that are covered in dust

 

Work with me on this. I'm not trying to prove myself right to myself, I'm trying to push this side of the argument so that I can hear the counterpoint I may be missing. I'm trying to debate it to hear it out, not to win.

Mine's a reg cab, 2wd with a 5spd; I think I am the lightest out of the bunch, and are more likely to notice a smaller change, because its a higher percentage for me than it is for everyone else. I have had several vehicles that were much faster and quicker than my pickup: a couple M5s, a m3, a trans am. We would lighten a 3K-3500 pound car by 15-20 pounds and you would feel it. I think I also notice any response more because of the manual trans. Taking 100 pounds (google search weight difference) off the front will most certainly help it stop better. It won't take any weight off the rear end, that is already too light unless I have a full tank, and it will be less weight to push and turn. Its not going to be substantial, but it WILL slightly help.

I think another reason the 6.0 generally wins over the 5.3 is because most everyone is automatic, and I'm not. YES, The 6.0 has about 40-50 tq lb ft and hp more than the 5.3, and that torque curve kicks in around 1500 vs the 5.3 at a little over 2K. The lower starting torque curve is nearly negligible with a manual. Its a question of the power vs weight. Its about 10-15% more power, vs losing ~2.5% weight (100/4000). (This may have just answered why the 6.0 is better, but I'm going to nitpick and keep going).

I think almost all of you guys are wanting to improve at the drag strip, and I'm driving like I'm at an auto cross. I don't race street lights, I don't lay rubber because tires are expensive, I don't go to the track. I take right turn yields accelerating in second between 40-50. I take hard right turns at 20-30mph depending on how full my tank is. I already keep speed up better than most, and that helps me cover ground. My pickup is not a weekend warrior, its my only vehicle, and I almost all of my driving is highway or through traffic.

In 10 years of owning, I have only towed once, and it was a small uhaul cargo trailer that weighed less than 2k pounds. I'm not planning on towing often. It may be once in the next 5-10 years. Having that option is just a huge bonus to me. Plus the nv3500 gears seem like they are basically set up for the higher revving 4.8L. Once that engine is gone that transmission would be horrible. I'm not trying to go from 0-100 shifting through four gears, I'm trying to put it in second and be able to go from 30-55 through a yield. I'm wanting to put it in third and not have to shift when passing a semi on a single lane back road highway.

How is a iron block going to create more traction when its mounted over the front axle? My steering in is just fine even at stock height. If I go lower it will be 2" at max, probably 1". If anything, making the front lighter will move the overall center to the rear.

If you all think 100 pounds doesn't matter, can you really not tell the difference between an empty tank and half or half and full? I sure can.

 

this is the point i was about to make: if you shed weight up front, it only shifts your front:rear weight distribution rearward, which really helps in a pickup. yeah, it won't be a ton, but it's something.

as for gearing - the 3500, while less than ideal (especially on 2-3 upshift), will still do alright with the 6.0
towing's even fine so long as you ain't trying to pull 7k in 5th at 75 for 14hrs. i'd pulled 6k almost a dozen times at 65 or less (often times in 4th), and been just fine.