(...continued)

Disclaimer: I'm much more interested in the mechanicals of cars than how clean they are. My Insight hasn't been washed in many months, maybe years. Sorry.

Here is the stance before:

(before)

(before)

Here is the stance after:
(after)

(after)

I only had time for a short but pretty comprehensive (e.g. bumpy, hilly & curvy) test drive in the rain tonight but so far, no rubbing at all and I didn't trim a thing from the fender skirts. If you want to install 185/60-14's, you'd probably want to go with a smaller spacer--they're a close fit w/the stock 165/65-14's but that's all I currently care about. Handling wise, it's hard to say but I WANT there to be a big difference so I'm hesitant to say what the big changes, if any, are without more of a test drive. When I get some more miles on the setup including rutted I-90 concrete, which tossed the car around a lot when stock, I'll report back.

Joel

 

Here are a few more random pics from the install:

(before - wheel to fender skirt gap -- all the way to my knuckle)

(after - wheel to fender skirt gap -- about an inch less)

PRO TIP: a 15 month old child strapped to your chest CAN sleep through the sound of an impact wrench


(before - hub/brake drum)

(after - spacer bolted on)

Joel

 

Does anyone have an opinion about what might happen to the rear wheel bearings when the load is displaced 25 mm. out from stock? The rear is pretty light, so maybe the bearings will do just fine. When I was young, I installed wide wheels on a Chevrolet. The additional width was all toward the outside; i.e., the additional width wasn't distributed equally, so the wheel load was displaced to the outside. The outside front wheel bearings wore out. This might have been coincidental.

 

Cantilever problem



This is a very real problem with wheel adapters and is mostly not considered or is just ignored. Front wheel spacers really goof up the front end geometry and even careful re-alignment is never very satisfactory. With the torsion rear beam suspension used on the Insight, this may not be a problem as far as the geometry is concerned.

The cantilevering of the load on the bearings that Art suggests probably will effect bearing life. The "correct" way to work around that bearing wear issue might be to install appropriate spacers between the mounting surfaces of the axle beam and the brake backing plate/wheel spindle instead of between the brake drum and wheel. This is a more complex and seldom used method but should deal with the bearing wear Art brings up but may create some other problems such as those with the lengths and locations of brake lines, etc..

Considering the trade-offs, the wheel adapters may not be the worse choice on a rear axle setup.

 

Skirt clearance

Currently, one of my projects involves adding drive sprocket adapters on the inside of the rear wheels for rear wheel belt drive. I had planned on about a one inch offset which is what you have. My main concern has been with the clearance at the REAR of the skirt and the wheel because the shape of the body narrows back there.

It is encouraging to see that there appears to be adequate clearance. I will be following your progress and comments with great interest and hope you will continue to report success.

 

Currently, one of my projects involves adding drive sprocket adapters on the inside of the rear wheels for rear wheel belt drive.

Care to start a new thread for this sounds intriguing

 

Wow

Joel,

You are a real trooper for having your child strapped to your chest and working on your car plus taking pics! My hat is off to you sir!

It's amazing that you didn't have to trim any material from your side skirts. I am looking forward to updates on this endeavor.

 

You have a lift in your garage?

Insanely jealous.

Let us know how it goes though. Very intrigued. I don't imagine this should impact MPG at all, so if it increases handling performance it may be worth it.

 

lol, I'm jealous too!

I would think it is possible to increase mileage because now you can cover more underbody area, and tighter tolerances always give better aerodynamics

 

@Hugh-Falls In my case, the adapter-type spacers were suggested by a reputable alignment shop who recently provided an "aggressive street alignment" and was responding to my request to further improve handling. In his "professional" opinion, the narrower rear track was a limiting factor and could be remedied somewhat with quality spacers. I could have achieved a similar effect with lower offset wheels but I like the stock wheels.

If my bearings wear more quickly, I'm prepared to deal with that as a side effect, similar to knowing that adding a turbocharger can increase the stress on and thus reduce the life of an engine as a trade-off for more power.

@Blue-Civic-Hybrid - Surprisingly, having a 20lb kid strapped to my chest enables me to spend a lot more time in my shop than I could otherwise. It turns goofing off in the shop into a worthwhile, wife appeasing activity.

@the non-lift-equipped masses--I set a life goal long ago to one day have place to work on cars that's out of the elements and has a lift. Our tax return one year was lift-sized and I realized that dream, complete with wife endorsement. Every time I hit that magic "up" button, I do feel very fortunate. Does that make me at least an OK person?

 

Haters gonna hate!



As one of the "non-lift equipped", I still hate you... but only on a jealousy level! Is that a Bendpak or another model? I'm jealous that you have it in your home garage! ( or is this some sort of out building/ barn/ detached garage?)

Nonetheless, you are an OK person for showing us your sweet lift.

 

Reasonable choice

JoelR: When I decided to add the sprocket adapters to the rear axle, I made the same choices you did and decided to go ahead anyhow. I am prepared to live with the consequences of increased bearing wear but was unsure about the tire/skirt clearances problems. Hopefully you will have that information available for us as you go along. I look forward to your future comments.

Retep: The rear drive battery trailer thread exists and describes what I had in mind for the rear belt drive sprocket adapters. These adapters are in the process of being machined right now and when they are completed and assembled, I will post the pictures there. It is good to know that I am not alone with increasing the rear tread width of the Insight. I had not anticipated any improvement in handling but thought that they might provide some understeer.

 

I've always dreamed of having a lift at my house, but have come to terms with taking my car to a 2 man service shop that said they will let me use their lift when its not in use. I'm not sure if they'll want me to pay to use the shop space or tools though but if I run into a snag and need help with something out of my league like tearing apart an engine, their hourly rate is reasonable compared to what I've seem other shops charge.

 

What was the weight of the spacer assemblies? Also, how much rear camber are you running? Looks like a lot, 2-3 degrees, but this may be an optical illusion. I am wondering if there would still be adequate clearance near the top of the tire with less camber. Are you still running the RE92s? Tires are the easiest way to improve handling, so I'm guessing you have some reason you're sticking with stock tires for a reason...just trying to figure out what your priorities are.

Bryce

 

Stock tires will give the best mileage hands down. So it looks like a balance of keeping the mileage while increasing handling.

 

@Blue-Civic-Hybrid: When we bought our house, it came with a 1200sq ft detached shop in addition to the attached 2 car garage. I tried to ignore that amenity as we toured the house which for many other reasons was a great deal and a good fit for us. After deciding we wanted it, I strolled out to the shop and gazed up at the 14ft ceilings and thought "a lift could sure go in here!" A full price offer was made that night. I've since added insulation, drywall, a heat pump, some tools and a lot of half-finished projects. I wish I had more time to actually take advantage but as you can see w/the baby foot in one of my pics, I'm taking every opportunity I can get these days.

Update on the 25mm spacers: my wife drove the car to work yesterday and described the change like this: "It's more stable on the freeway. It feels like when turn the steering wheel, there's more slack, like it doesn't turn as suddenly." I'll definitely have to confirm it myself but I think she could be describing an increase in understeer which makes total sense. My longer term plan is to add a rear sway bar and perhaps a stiffer front sway bar so ultimately, I think the understeer can be counteracted by these bars. Hopefully the end result is more stability, higher cornering limits, better transient response (e.g. it goes where you steer it with less body roll) and a tad less understeer than stock.

That's the theory anyhow.

Joel

 

Variable rate springs

"........... there's more slack, like it doesn't turn as suddenly." I'll definitely have to confirm it myself but I think she could be describing an increase in understeer which makes total sense. My longer term plan is to add a rear sway bar and perhaps a stiffer front sway bar so ultimately, I think the understeer can be counteracted by these bars. Hopefully the end result is more stability, higher cornering limits, better transient response (e.g. it goes where you steer it with less body roll) and a tad less understeer than stock.

That's the theory anyhow.

Joel

First, you may want to consider replacing the OEM springs with a pair of after market variable rate "performance" springs at the REAR axle to limit roll; certainly preferable to adding an after market sway bar with all its generic pivot and isolator bushings and connecting links.

 

@Nashco: As Bryce said, my goal to see how far I can improve the handling while keeping the stock tires since anything else reduces the mileage. I'm not trying to save money by saving fuel, I'm just trying to maintain my current ~60mpg mileage while making the car more fun to drive.

My alignment settings (called "semi-aggressive street use") are currently:
Front: -1 degree camber, 2.1 degree caster, 1.5mm toe in
Rear: -1.1 degree camber, 3.5mm toe in

I can increase negative front camber to about -1.5 degrees using the narrower bolts the shop installed. The above setup has been a nice improvement over how the car was before (+.19 degree camber, 3.7mm toe out in front). Rear camber can be adjusted using special spacers behind the brake/hub assembly where it bolts to the axle but I'm going to hold off on that until after sway bars. What I'm saying is my rear camber is essentially stock and probably the same as yours.

Joel

 

Just a side note....

No matter how you offset the tire, be it via a different rim or the spacers, any time the tire is displaced from the axis of the wheel bearings, there will be more torque loading (side-loading) of the bearings.

_______________________

I really do like the idea of moving the rear wheels out as well.

Obviously cornering stability is a big factor....

Driving in the winter snow is another. I notice the back end moving around quite a bit since the rear wheel track is not in the same road surface as the front. Moving the rear tires out slightly might help this.

Jim.

 

I've never even heard of an Insight wheel bearing failing. They seem pretty robust. I doubt it will be a big deal. But something to watch out for.

 

@Huge Falls: Actually I'm currently trying to organize a group buy for a set of 4 matched sport springs I'm working with Swift Springs to build. For the rear sway bar, I'm looking into a design similar to the Shine Racing bars for VW rear torsion beams (fits into to rear beam, very tidy) that Guillermo on this board customized & installed. In his case, the stiffness seemed too extreme for daily driver use; enough that he removes it for winter. I want to go less extreme in the rear and possibly to match it with a slightly larger front bar too.

 

Update: I've had the spacers on for about a week. I wish I could say that the car handles great now but in truth, it doesn't feel that great with spacers alone. A guy at a local speed shop offered a theory: if you think the car needs a stiffer rear beam to begin with, adding spacers gives you increased leverage and thus makes the rear feel even softer. Add to that the additional understeer and I can't recommend that others do this mod without doing other stuff first.

I will try taking the spacers off one of these days for an A : B and back to A comparison. I'm very curious how things would feel with a stiffer rear beam so I'm still working on that plan as time allows in addition to seeking damping, springs and bushings solutions.

Joel

 

....A guy at a local speed shop offered a theory: if you think the car needs a stiffer rear beam to begin with, adding spacers gives you increased leverage and thus makes the rear feel even softer. Add to that the additional understeer and I can't recommend that others do this mod without doing other stuff first....Joel

Yes, it's true that the slightly narrower rear end without spacers will be slightly stiffer when looking at the stiffness of the torsion bar alone.

However, rear end stiffness of the beam is also affected by the slightly greater mechanical advantage of the car chassis "leveraging" the torsion beam of the trailing arm suspension.

When you add the spacers, the torque reaction of cornering is actually slightly lessened by addition of the spacers, since the rear tires now track on a wider stance.

Think of how much torque the chassis would have over a trailing arm if the tire width spacing was only 12 inches per side. It would bend the stiffer trailing arm just as easily because there is more torque to accomplish the task, even though the trailing arm is stiffer due to it's short length.

So in summary the "tipping" of the car when cornering should be the same with or without the spacers, considering that the torsional stiffness remains the same in both examples.

The only way to stiffen it, would be to either stiffen the existing torsion arm, or replace it with another.

Jim

 

Thanks Joel for your feedback and your daring into this foray for an upgraded suspension system. That rear sway bar you speak of is very interesting, I'm thinking it's like my Progress bar for my Fit. Once I put that on, it made the Fit handle so much better.

 

Sorry Mark, I hope I didn't mislead you. I do plan to make it up to you and others one of these days with some solutions to the funky Insight handling and I fully intend to make use of the spacers. I'm starting to think my car might have some sort of handling "problem", something I asked the alignment shop to look into. They said all of my bushings looked tight but when I drive, I do not feel a solid, compliant, well-controlled ride. It feels like parts that are supposed to be isolated in rubber are now moving around, all sloppy-like. When I drive my 2010 Fit Sport, it feels nice and tight. The Insight by comparison feels harsh, like small bumps are easily felt, like it's unsettled on rough surfaces, etc. Tire pressure is less than 40psi right now. I replaced all 4 dampers w/new OEM parts about 2 years ago. Car has 140k miles so I think its rubber bits need a refresh.

 

I don't feel mislead at all, in fact I like the improved ride, but that is mostly due to the heavier springs that I installed a few years ago. As far a definitive answer on the handling, only time will tell, but so far I haven't noticed any negatives.

 

32mm Spacers

I installed 32mm spacers a couple days ago. I heated the fender skirts and bowed them out a little to provide needed clearance. I have had no rubbing even over big bumps at speed. The car seems more stable on the gravel. The camber increased a bit so I will shim the axle shafts more to neutralize it. So far I like the way it drives.

 

Wow, that's pushing the envelope!

I'm surprised by the camber change you mention since it's a beam and unless the beam is sagging from having its endpoints (e.g. the wheels) moved out, camber change seems like it would be effectively zero.

As for the driving experience, when I did 25mm spacers, I think the overall driving experience got worse and highlighted the need for a stiffer rear beam and/or firmer springs/damping. I don't drive much on gravel so can't comment on the change there but it makes sense that it would be more stable.

 

32mm Spacers

Moving the wheel our significantly increases the torsion loading. As long as it stays in the elastic range and the fatigue limits, I am not to concerned. I like the way it looks with the wheels moved out. I bought the car in January and when I brought it home on snowy unpaved roads, The car seemed to be very shifty. It has been shifty on a freshly bladed gravel road as well. If this minimizes its twitching, I will be pleased.

 

When are you planning to get stiff springs on their Joel?

I guess it does improve the 'stance' of the car when viewed from behind. I think I may weight until i get something sorted with the bushes. The UK breaking day should give me access to the right bits to develop something!

My concern is too much movement with 25mm might see fender covers going flying!

I'd like to try 15 then maybe tape some foam inside the covers to see if we get move movement from parkes position but for that we'd need to get longer wheel studs. Something from the other Honda tuners or even just an OEM Honda stud could prove appropriate for that.

 

When are you planning to get stiff springs on their Joel?

I've already got stiffer Chevy Aveo springs on mine (not a great mod). The stiffness I'm after is in the torsion beam but I haven't had time to pursue how I want to achieve that. I definitely want a more year-round appropriate setup than Guillermo went with when he added the VW Jetta race bar to his.

You know, there are some curious holes in the corners of the rear axle beam and a tab w/2 holes in the center that attaches to nothing -- you think there was a sway bar on there at some point during development of the car?

 

I now have 1500 miles on with the 32mm hubcentric spacers. So far I am very pleased with it. There are no signs of rubbing. I aligned the rear so I have about 1/32" tow in -.3 degree camber. This should give good tire wear and handling on loose gravel seems to have improved significantly.

 

Did you ever weigh the spacer assemblies? If you have easy access to a scale, I'd really appreciate the info.

Bryce

 

@Nashco - No, I didn't weigh them yet but I'll throw 'em on the wife's kitchen scale and see what it says this weekend. How about a trade for a bit more info/pics on those lovely Koni's?