Full EGT Suspension Swap.

[Jimmy]

Here are some more measurements getting closer to seeing exactly how hard it's going to be to swap the IRS. Obviously it's going to require a lot of fabrication, but I wan't really sure how much until tonight.


This is the measurement from the face where the wheel bolts up to the outside face the trailing arm. This is important because if this were off by too much either the trailing arm would not be parallel to the centerline of the car (which would do funny things with the alignment as the suspension compressed) OR that the stock mounting points would not be usable (meaning more fabrication).

On the stock Festiva suspension that measuments is approximately 5.25"



This is the same measurement on the EGT suspesion. The EGT trailing arm is narrower than the Festiva, so the stock Festiva mounting bracket has some room to play with.

It's close enough that it will work fine.



The EGT trailing arm is about 9 inches too long. It can be sectioned easily enough. Or a pair could easily be fabricated to use spherical rod end / be adjustable if you really wanted to tweak the geometry.



This is the EGT rear crossmember with sway bar.



This is the EGT crossmember with 1 transverse link stuck on for reference. As you can see the crossmember is almost as wide as the entire Festy rear axle. Either the crossmember is going to have to be narrowed or the transverse links are going to have to be shortened. Or both. I need to make some CAD models and play with the geometry and see what's going to work best. Neither option is too bad, the transverse links should be made adjustable anyway, narrowing won't be any added work.

I also measure the difference in height from the center of the wheel to the top the fully extended strut. I didn't get any pictures, but the difference is that the EGT is about 1" longer than the Festiva and a little less damper travel. Not necessarily bad, the upper mount could be designed to restore some of that distance.


The big question is still whether the EGT rear struts will have the right angle when stuck in the Festiva towers. It's a big if.

So right now it looks like it going to require fabrication/modification of:
6 links
Festiva trailing arm mounting brackets
Upper shock mount
Crossmember/builing sub-frame
Removing spare tire well/filling hole in floor
Reinforcing shock towers/bracing
Mounting crossmember
Rerouting exhaust
Coil-over sleeves
Sway bar.

I'm probably overlooking something.

[glacius182]

Man, that's some nice work you're doing. Don't give up!

[Jimmy]

First test fit on the car.


The knuckle is being held in up by the jack. There is a few inches of extension in the damper, only maybe 2-2.5" of compression travel with that much wheel gap.

No comments on the fart cannon. It was cheap and I really needed a muffler.

There is about 3 degrees of negative camber on the wheel the way it was sitting. That's pretty good considering it was just thrown in there. I think if you set up the geometry to give you 0 degrees you'd end up with more wheel clearance at the fender than the stock Festiva stuff has.

The beam that crosses horizontally across this picture is the EGT trailing am. The bracket above it is the stock Festiva trailing arm bracket. They line up nicely. Shortening the EGT trailing arm to work will be easy enough.

The EGT transverse links will have plenty of room, once the exhaust is gone... And if you look at the trailing arm pic again, you'll see why the spare tire well is probably going to have to go too.

There is a bushing under the big washer. I used a polyurethane sway bar endlink bushing that I enlarged the certer hole in. It works just about perfectly.






So far I haven't run into any really difficult hurdles. I would rather not have to cut out the spare tire well, but it may be unavoidable.

Tomorrow, if all goes well, I'm going to start fabbing up a prototype crossmember and try to figure out the best way to mount it. And then maybe shorten the trailing arms...

[Jimmy]

Couldn't leave well enough alone for one day. I went ahead and pulled the muffler, heat shield, and rear bumper cover to get a little better look at what's ahead.



Yep, no way around it. That spare tire well has to go.



At least there are boxed "frame" sections on three sides of the area I have to construct the inner suspension mounts inside of. Should make things fairly easy. I was going to try to narrow the EGT crossmember, but now that I get a look at things, I think I'm just going to build my own.





That is the shiniest, most rust free spare tire well I've even had on any car... Bye bye...


Center rear exit exhaust or in front of the passenger side rear wheel?

[htchbck]

all I can say is wow :!: I've been watching this buildup and rooting for ya the whole way, but I honestly didn't expect it to get this far without some major major difficulties... I'm looking forward to the finished product, as I'm sure everyone else here is as well.

P.S. what size tires are those on the tracer wheels? I have to get tires for my new escort wheels soon, and I'm still debating whether to go with 175/65/14s or 185/60/14s

[Jimmy]

all I can say is wow :!: I've been watching this buildup and rooting for ya the whole way, but I honestly didn't expect it to get this far without some major major difficulties... I'm looking forward to the finished product, as I'm sure everyone else here is as well.

P.S. what size tires are those on the tracer wheels? I have to get tires for my new escort wheels soon, and I'm still debating whether to go with 175/65/14s or 185/60/14s

The tires on the Tracer wheels are 185/60-14.

I'm really surprised I haven't hit any bigger hurdles yet too. Now that I've said that, I've probably jinxed myself.

Autocross starts three weeks from today. Lot's to do.

[Silv3rBull3t]

What class do you plan to run in? Very interested in your progress. -Kyle

[Safety Guy]

GO JIMMY!!

Too bad about that shiny spare tire well.

Karl

[Jimmy]

What class do you plan to run in? Very interested in your progress. -Kyle

I was expecting to run in Street Modified, but that would require some creative interpretation of the rules.

SM rules say "Suspension is free as long as the stock mounting points are used. I'm using the stock mounting points - the trailing arm pivots and the tops of the struts are the only mounting points in the stock car. I'm just adding a couple of mounting points too. Adding mounting points is alright if you are just adding a Panhard bar, but that's about it. This is far from a panhard bar.

SM also has a minimum weight (1800lbs) that I'm not sure I'm going to meet.

I imagine it will take at least most of the first season to get the car sorted enough to even be noticed, so I'll probably just run SM or SM2 for a while unless someone protests. SM2 is probably one of the most hottly contested classes in my region - a lot of really fast RX7s and Miatas.

Should be fun.

[Safety Guy]

Jimmy wrote:

"This is far from a panhard bar."

That's an understatement!

As for the cut out spare tire well, perhaps you could make some furniture out of it? Hate to see such a nice hunk of painted steel go to waste!

Karl

[Jimmy]

Jimmy wrote:

"This is far from a panhard bar."

That's an understatement!

As for the cut out spare tire well, perhaps you could make some furniture out of it? Hate to see such a nice hunk of painted steel go to waste!

Karl

Lol. Yeah I thought for a second that it would make a nice bathroom sink.

[Silv3rBull3t]

Cool I run in SM as well... There is tons of competition in my area (STi's, EVO's, M3's, Civic's, etc) I do pretty well considering the odds but this season may change. I am getting my hands on some 13x8's as we speak and going to get Kuhmo V710 215/50's for them.. Should be pretty competitive. -Kyle

[Jimmy]

Here are a few things I got done today. Nothing exciting I'm afraid.

This is the suspension at full compression - bottoming out the damper. Not a very good pic, but the significant thing is that the damper bottoms out before wheel begins to tuck behind the bodywork. I'd like a little more damper travel than that. I'll have to think about that one.


This is the shortened EGT trailing arm bolted into place.

So I started thinking about the cost/benefit ratio of this project, along with the desire to keep the car legal for certain racing classes.

It occured to me that it would be possible to use the EGT rear knuckles as the basis for a beam axle similar to what the Festiva has stock, except that the alignment would be adjustable, it would use a Panhard bar for latteral location and setting the rear roll center. It could also be designed with the use of an off the shelf swaybar off of another production car, allowing some tuning in that regard too.

Basically all of the benefits of the multi-link except that it wouldn't be a truly independent suspension.

It would also be easier to integrate into the Festiva chassis.

I don't know...

[Jimmy]

This is the part of the project where I start to question what I am seeing.



No spare tire well. Half way through cutting it out, I accidentally let the magic smoke out of my 12 year old grinder. Had to finish it up with the Sawzall. I need to go back and clean the edge up - plus fabircate a new floor piece to fill the hole.

OK, I can believe that I see that.



Passenger side rear tire with the trailing link hooked up.



Driver side rear tire with the trailing link hooked up.

Both of those are easy to believe.



What I cannot believe is that the rear stock EGT rear crossmember, without being narrowed, is almost the perfect width. I stuck it in upside down because if it were right side up the ends pieces would interfere with the stock Festiva subframe before it was up close enough to the floor to have the right geometry, but other than that it looks like it will work with just the ends cut off, new mounting system fabricated.

I like to use as much factory stuff as possible. It gives a little peace of mind to know that there are thousands of cars out there with the same parts that haven't broken.

This is good. This is very good.

Back to work... More later...

[muscle_Car1]

Very good work. You are a festiva pioneer.