Aero-Modding the 4Runner

[jeff88]

Oh OK, I see what you're saying. I think my plan for the roof rack is the same as what you're saying. The rack will run the full length of the roof. The front will match the windshield and from there will match the template. I will then have a removable kamm that can attach to the rear end of the rack to extend the template even further behind the truck.

EDIT: I think based on this template with an imaginary roof rack, it might be better to angle the front of the rack backwards just a little bit more than the windshield. I think that might help keep airflow attached around the "corner" of the windshield/roof angle. Although, at the same time, the windshield seems to be pretty close to the template anyway.

[jeff88]

Well, another tank is in the books. Once again it was right at 20MPG. All week felt warmer, but according to my weather site, it was actually colder. So I'm thinking I might put the airfoil and crossbars back on for a little ABA testing while it is cold(ish).

[jeff88]

Well I had a minor set back this week. On the way to school, about a mile up the road from home, I heard a nasty sound. I thought it was my timing belt, but the truck was driveable. It turns out I was close as my UltraGauge had a P0305 code: misfire on cylinder 5 (my UG is in my Corolla, so I couldn't check until I got home). Generally you would think with new spark plugs the culprit would be the ignition coil and/or wire. Well when I took the coil off, I decided to pull the plug, just in case. I'm glad I did! The node (or center electrode) completely broke off! Now I'm nervous about replacing the plug. Where is that node? I don't want to cause further damage to the cylinder/piston.

Here's the broken plug:


Anyway, non-aerodynamic issues, but aerodynamics obviously don't matter if the truck isn't going anywhere.

[CFECO]

It's best to use the factory or "Quality" Name brand plug. I have NEVER seen fancy spark plugs pay for themselves. Is the truck running some "Lean-burn" set-up or what. It really takes very little to, ignite the A/F on a "standard" ICE, assuming the A/F ratio, and compression is adequate. The MOST stressful engines in use, Top Fuel Dragsters...use standard type spark-plugs.

[jeff88]

As far as I know, the truck is not running any sort of lean burn outside of factory specs. I haven't done any mods to this yet. The plugs are supposed to be OEM replacement. I didn't get anything fancy and I didn't get the cheapest ones I could find.

I just happened to be with my friend (and mechanic) tonight, so obviously I talked to him. He said it is probably just a defective plug and the piece that broke off will be burnt up and long gone by now.

[jeff88]

I haven't really updated this recently. The truck has been at the mechanic since late december. The owner wrote it off and bought a new vehicle (Escape Hybrid) and said that if I pay off the work to diagnose, the truck would be mine. So today, we finally got it home. When my friend's garage is finished getting rebuilt, he is going to help me put it all back together (and figure out what went wrong in the first place).

I can then start doing some ecomods. I want to put in an electric fan for sure, not sure about any other engine mods yet (If anybody has any ideas, I'm all ears ). I will also end up putting some aerodynamic mods on. Definitely going to some sort of air dam, probably an extended belly pan (the front has a wannabe one) and then eventually the roof rack kammback that I originally wanted to do.

[SoobieOut]

Here's a mystery of the 1997 4Runner. My girlfriend just traded in her 1997 4Runner for a new 2014 4Runner Trail.

The old 4Runner got between 22-25 MPG highway, which I witnessed more than once. The new 4Runner gets 18 if your drive very carefully. I know the new 2014 has a larger engine, but this is a giant step backwards for Toyota in terms off FE.

There must have been something special about the 1997 year for the 4Runner.

[elhigh]

That '97 'Runner was available with a 4-pot engine, the biggish 2.7l 3RZ. I'm not familiar with them but one would imagine it's going to be a bit thriftier than any comparably- or larger-sized V6. I see 2014s can be had with a four as well but I know even less about those than the 3RZ.

I see the Trail package is available only with the 4.0 V6, so right there she's picked up about 12% more engine displacement. That'll take a hit at the pump.

The new Runners weigh in at a solid 4400 lbs, the '97 is listed at just under 4000. That would make a big difference too.

Also, the new 4Runner is about a foot longer and as much as five inches wider than the old one. It's just a bigger hole to punch in the air. Extra mass, more cylinders, more drag...I guess that would do it.

[Xist]

The 4.0-liter V6 adds Dual VVT-i which improves horsepower, torque and fuel economy

Toyota 4Runner - Wikipedia, the free encyclopedia

According to that page, the fifth-generation 4Runner only had the 2.7-liter in 2,010, which had 157 horsepower, while the third-generation had 150. The 1,997 was rated 18/22, while the 2,010 was rated 18/23, so yes, the engines were both more powerful and more efficient, albeit slightly, but the 4L has 270 horsepower! With slightly more horsepower per liter, they might have traded economy for power.