S10 Zr2 project thread

[ksguy]

Hey all -
I got started aeromodding my S10 this weekend. I'm adding an aero cap and underbody pan.

Starting vehicle is an 02 S10 pickup, Zr2 off road package, manual transmission. My total round trip commute is around 60 miles per day - 50 highway, and 10 city. I'm averaging around 17.3 mpg now (depending on A/C usage). Highest tank is 17.9 w/o A/C. I'm hoping for at least 20 with these mods.

I'm starting with the cap. My design will be fairly simple - I'm using 5mm plywood and a boat building method called stitch and glue. There are no complex frames to build - I'm putting in place basic framework that will be a starting point for the initial panel - the remainder of the panels will be placed by bending, tracing to the first panel, cutting, then "stitching" to the first panel. The 5mm ply should be flexible enough to handle the compound curves. In the end, structural stiffness will come from the joints and the use of biaxial fiberglass tape. The remaining surface of the panels will be covered in fiberglass cloth.

I have fiberglass and epoxy on hand as leftovers from a boat project, so my materials budget for this build is around $50 - about 6 to 8 weeks worth of savings I'd expect with a 15% mpg gain.

I started by building a frame around the bed of the truck made of 1x8 pine on the sides and a 1x6 ripped in half for the front and back. I created an overlapping joint at the corners, held together by epoxy putty. Once it cured, I fastened it to the truck using turnbuckles connected to the tie-down points in the bed.

The vertical frames at the front will be used as the starting point of the main arched panel. I'll temporarily fasten the leading edge of the top panel to the top of those, then flex it down in the desired curve to meet the edge of the rear frame.

Here's pics of this weekend's progress.

[Joris]

Looking good! While you're at it, get rid of the mudflaps!

[MetroMPG]

Subscribed for the stitch 'n' glue aerocap!

[grins2go_brett]

I used to own a ZR2. Great truck! Kept up with, and did better than some jeeps and Tacoma's I used to run around with on the Arizona rocks. Good luck with the build!

Originally Posted by Joris

Looking good! While you're at it, get rid of the mudflaps!

Check your local/state laws before removing the mudflaps. Some states, like AZ, require certain vehicles (Pickups) to have rear mudflaps. Some of the guys around here make removable mudflaps, so they can take them off on the trails, but be legal on the highways. Many of them learned about the law the hard way...

[Smurf]

17.4MPG on your ZR2 is pretty good, considering the factory lift kit, 4x4 dragging you down, 4" wider rear axle, knobby tires, etc.

Ever thought about an all-wheel drive conversion?

[ksguy]

Originally Posted by Joris

Looking good! While you're at it, get rid of the mudflaps!

Hm...not sure on that one. As grins2go_brett mentioned I'm not sure if I have to have them or not. I could look in to it.

Originally Posted by grins2go_brett

Great truck!

I'm a fan. It has 175K on it and it hasn't given me any serious problems. It's my third S10 so I know how to handle it if it does get finicky on me.

Originally Posted by Smurf

17.4MPG on your ZR2 is pretty good, considering the factory lift kit, 4x4 dragging you down, 4" wider rear axle, knobby tires, etc.

Ever thought about an all-wheel drive conversion?

I am actually impressed with 17.4 also. I thought I'd top out at 16 before making mods. I read up on the 4x4 dragging this truck down, and the possibility of adding locking hubs. Turns out the front differential disengages from the cv shafts in addition to the transfer case disengaging the front drive shaft, so the front wheels aren't turning as much extra weight as I thought.

The Bravada awd conversion isn't really appealing to me - other than not wanting to spend the money, I'm not really sure why, though. What are the potential benefits?

[2000mc]

I know you're not looking to put more money into it right now, but I noticed the manual is only rated 12/14/16 while the auto is 14/15/18. I would suggest looking into the differences in gearing of the trans and differentials, if it's not already geared too low, with the aerocap and smooth underbody, it could probably make use of higher gearing. If it's geared too low already, you might see smaller than expected gains from the aerodynamic improvements. Hopefully there is a fifth gear swap available.

[Smurf]

In Kansas, the Bravada/Astro AWD swap doesn't make as much sense as it does here in Wisconsin. If my S10 was 4WD, I'd probably do it, as I've priced parts locally to get it done for under $400.