An uninspiring build - Page 5

never monday · 08-11-2009, 04:42 PM

Quote:

Originally Posted by Greg_Volkman

I love to see those 37" tires smoking with that 4 cyl!

too bad they didn't use a Ferd 8.8

did some updates to the build in the first post.

**wrangler2007** · 08-11-2009, 05:02 PM

What all are you going to strip off the jeep to reach 2500lbs?

never monday · 08-11-2009, 05:09 PM

Quote:

Originally Posted by wrangler2007

What all are you going to strip off the jeep to reach 2500lbs?

from
http://www.allpar.com/model/cj/specs.html

Curb weight: 3,092 lb (1,403) with four-cylinder, 3,229 lb (1,465 kg) with I-6

it won't take much.

**wrangler2007** · 08-11-2009, 05:19 PM

Quote:

Originally Posted by adam728

Which is possible with a turbo if setup that way.

On a supercharger you could be making boost at 1K, but using more hp to drive the supercharger than it is adding to the engine. This creates a situation where being supercharged will actually yeild less power than stock!

If it were my Jeep and I wanted forced induction I'd go turbo, personally. Especially since you can rob well engineered factory parts to make it happen.

Think about that...a supercharger pushes more air andthus uses more fuel for more power even driven off the motor's pullies...I'm sure no one would buy a supercharger if what you said were true no companies making a supercharger could stay in business. Even with the 2.4l there is a power increase. Te increase isn't as big as with say a v-8 but it's still noticeable and still a viable option

**wrangler2007** · 08-11-2009, 05:20 PM

Can't wait to see the build.

adam728 · 08-11-2009, 08:37 PM

Quote:

Originally Posted by wrangler2007

Think about that...a supercharger pushes more air andthus uses more fuel for more power even driven off the motor's pullies...I'm sure no one would buy a supercharger if what you said were true no companies making a supercharger could stay in business. Even with the 2.4l there is a power increase. Te increase isn't as big as with say a v-8 but it's still noticeable and still a viable option

Sorry, I didn't really mean to further this thread off track. I amvery interested in what Never Monday does with this build (I'm a fan of the LCG builds).

I just jumped in because I hate the generalizations made about turbo vs superchargers.
Turbo lag
Turbos only make power at high rpm
Superchargers make tons more torque
Etc etc

Most of these sterotypes became well seeded in the automotive enthusiest communities because they held very true, 25 years ago. Carbureted blow-thru systems and very basic EFI systems severily limited boost/timing/fuel control, and turbo car often had tons of lag. Now variable vane turbos, direct injection, and nearly limitless fuel/timing/boost control has transformed what turbos are capable of.

Superchargers take power to make power. I didn't claim that they don't increase power, I just claimed that there is a threashold that must be reached before they start making power. It's entirely possible for a supercharger to be making boost near idle, but take 10 hp to spin it while only building 7 hp over stock. Net gain? -3 hp. Bring the rpm up a bit and you'll quickly cross that threashold and start making much more power. Not all systems will act this way, but the "superchargers = torque" is just another generalization that doesn't always hold true. Plus, since a supercharger takes power to make power it can never have the usable power potential of a turbo. In general (there's that stupid word again) it takes 1psi more boost from a supercharger than from a turbo to get the same usable hp.

Turbos can spool at quite low rpm. I loosely follow some VW boards because there is a turbo'd Passat sitting in our driveway. Some of these cars will reach max boost (10-12 psi) by 1800 rpm, and be pushing a fair amount of boost (2-3 psi) by 1200 rpm. Some of the nearly stock cars can lay down over 200 ftlbs at the wheels from 2300 rpm to over 5000 rpm in a very flat fashion.

Anyway, I'm about to fall off my soap box. I just wanted to put in my 2 cents against the turbo vs supercharger stereotypes.

On with the build, in whatever direction you chose to take it!!!!!

never monday · 08-11-2009, 08:41 PM

Quote:

Originally Posted by adam728

Some of these cars will reach max boost (10-12 psi) by 1800 rpm, and be pushing a fair amount of boost (2-3 psi) by 1200 rpm. Some of the nearly stock cars can lay down over 200 ftlbs at the wheels from 2300 rpm to over 5000 rpm in a very flat fashion.

those are impressive numbers.
But what good is 5000 RPM with 100:1 reduction?

**Wheelin98TJ** · 08-11-2009, 09:09 PM

2,500 lbs seems a bit optimistic to me.

How are you going to lose all the weight while still adding all the necessary parts?

never monday · 08-11-2009, 09:18 PM

curb weight is with all the street stuff
doors, windshield, wiper motor and linkage, tail gate, dash, HVAC...etc

2500 is optimistic, 2700 is doable with my weights from the black truck

**jforse** · 08-11-2009, 09:33 PM

great project!

adam728 · 08-11-2009, 09:34 PM

Even their curb weights seem quite optimistic. Luckily you are starting off with a much lighter rig than me.

01 Sport, 4.0L, auto, AC
Full steel doors, soft top, no rear seat, 2" bb, 33x10.50's, stock aluminum wheels, no extra skids or anything.

Less than 1/2 tank of gas, pretty much exactly 300 lbs worth of people inside (me and a skinny girl). Tipped the scales within spitting distance of 4000 pounds. Remove people and gas and I was still well over 3600 lbs.

never monday · 08-11-2009, 09:47 PM

my 02 was almost 3200 even, comp ready

**wrangler2007** · 08-11-2009, 10:38 PM

You run a fuel cell with this build? I assume that an aluminum fuel cell will save some weight instead of adding a skid to your stock gas tank?

never monday · 08-12-2009, 06:35 AM

Quote:

Originally Posted by wrangler2007

You run a fuel cell with this build? I assume that an aluminum fuel cell will save some weight instead of adding a skid to your stock gas tank?

not enough for me to justify loosing part of the bed. I think there is a more Savvy solution available.

EvilM0nkey · 08-12-2009, 08:46 AM

Quote:

Originally Posted by never monday

not enough for me to justify loosing part of the bed. I think there is a more Savvy solution available.

Seriously.
Lets replace a darn near unbreakable plastic gas tank with a fuel cell and take up a bunch of space in the bed that could be used for useful things, all the while creating a gigantic hole under the jeep on which to get hung up with rocks. OH unless you run a skid plate there!

I don't mean to pick very much, but this kind of stuff is crazy.

Lets use our brains here before we start spouting ideas.

Light weight + strong skid plates covering an already light as possible tank is the best way to go. There aren't very many circumstances where a fuel cell is required in a Jeep.