Losing Weight Off Your Engine <Write Up>

Matthew Starr

Matthew Starr

Banned
Ok, so I've been meaning to do this write up for a while and I keep forgetting so here it is. Side note (the following has not be tested on a dynamometer so all that is said is of my experience and opinion)

So using some common physics I came up with this idea that taking weight off of your engine is not only going to give you better performance but will allow you to feel the difference and increase in power adding modifications. Since I don
 
Register to hide this ad
right, i can see this thread is going to be one about peoples own opinion and all, but after spending all that time and money, why not buy a sports car?

EDIT i read that you are trying to make yours a "one of a kind" race car, yes all those things will help by adding power back into making your rig fast

there are many more things you could do, basically endless ideas, striping the car, replacing body parts, engine swaps, forced induction, synthetic fluids, rebuilt kits, re-gearing, smaller tires. but anyways good luck!
 
Last edited:
So these are the mods you have done? Any others?

If I am correct the pulley and the shaft are close to $600. For that price you could buy or almost buy a supercharger, I think.
 
In my opinion I really think everyone should, at least, do the electric fan conversion. This thread is simply an idea that doing these modifications first will give you better results with future hp increasing modifications, and this thread is for anyone who would like to get more power out of their 4runners. So if you're just gonna be negative about making any modifications, voice your opinion somewhere else.
 
While I don't dispute your increased performance, I do think your math is a little fuzzy. I don't just think you can say your crank has to turn 10lbs and call it a day. Its a bit more complicated than that. I'm pretty sure you would need to calculate the moment of inertia of each part you remove, then see how much torque the crank uses to rotate the part. For the example, rotating a pulley from the outside requires less force or torque than rotating a bearing from the center.

Besides that, most of these parts are moving at all times the engine is on, so they have some momentum. Therefore, they wont strain your engine much. In my mind, the biggest advantage of the electric fan and crank shaft pulley would be making your engine start easier, the effect when it is moving may be minimal. The lighter drive shaft I think would show the most improvement in low speed acceleration.

Anyway, those are just some thoughts from my slightly scientific mind.
 
benormous said:
While I don't dispute your increased performance, I do think your math is a little fuzzy. I don't just think you can say your crank has to turn 10lbs and call it a day. Its a bit more complicated than that. I'm pretty sure you would need to calculate the moment of inertia of each part you remove, then see how much torque the crank uses to rotate the part. For the example, rotating a pulley from the outside requires less force or torque than rotating a bearing from the center.

Besides that, most of these parts are moving at all times the engine is on, so they have some momentum. Therefore, they wont strain your engine much. In my mind, the biggest advantage of the electric fan and crank shaft pulley would be making your engine start easier, the effect when it is moving may be minimal. The lighter drive shaft I think would show the most improvement in low speed acceleration.

Anyway, those are just some thoughts from my slightly scientific mind.
Click to expand...
You are right that the constantly moving components do have momentum but trying to turn spin 3 pounds is still easier than trying to spin 10 pounds. And yes the driveshaft did show the most gain in low speed low rpm acceleration, the fan is massive in size and takes more to spin it, not to mention its also moving air which adds even more resistance and the fan clutch is massive in weight in my personal feeling of lateral g's during acceleration through all rpm's getting rid of the belt driven fan made the biggest difference. Very good points though, thanks.
 
Matthew Starr said:
You are right that the constantly moving components do have momentum but trying to turn spin 3 pounds is still easier than trying to spin 10 pounds. And yes the driveshaft did show the most gain in low speed low rpm acceleration, the fan is massive in size and takes more to spin it, not to mention its also moving air which adds even more resistance and the fan clutch is massive in weight in my personal feeling of lateral g's during acceleration through all rpm's getting rid of the belt driven fan made the biggest difference. Very good points though, thanks.
Click to expand...

why arent you watching the superbowl??!?!
 
I'm watching the super bowl, right behind my laptop screen... Can you believe that crap, the ball was across!!! :bash:
 
Last edited:
benormous said:
I'm pretty sure you would need to calculate the moment of inertia of each part you remove, then see how much torque the crank uses to rotate the part. For the example, rotating a pulley from the outside requires less force or torque than rotating a bearing from the center.
Click to expand...

I was about to bring this up but i guess you beat me to it, i wont get to deep into the dynamics behind rigid body rotation but like you said 3lbs is better than ten
 
You must log in or register to reply here.

Members online

No members online now.
Total: 213 (members: 1, guests: 212)

Forum statistics

Threads
278,306
Messages
3,554,045
Members
248,016
Latest member
Advally Service

Share this page

Trending content

Back
Top