extending the wheel base of a corolla

[landslideATX]

ok, someone told me you could extend the wheel base of the corolla if you have adj 4-links and pick up a sr5 drive shaft and something els. i can't remember what all they said. does anyone know anything about this?

[dr.occa]

tension arms will also help.

you can use the longer back half of the sr5 shaft w/ adjustable 4-links. you'll need to make sure to keep your pinion angle correct when doing so. i'm not sure though if you'll need to go with slightly longer 4 link sleeves to do so. keep in mind you have a panhard that has a static chassis mounting point that you can exceed either or you'll have to relocate that mounting point for the panhard.

[landslideATX]

how much of a difference is there in the length?

[Prime123321]

This could be done but to what expense/availability of parts and reasoning? What type of driving are you building the car for IE. drifting, grip, track, time attack, rally/offroad? Is it going to be a daily/toy or a single purpose only car? This sounds like a novel idea but to what end? Sorry to sound critical but I would like to help you with this if possible.

The route I used to extend my 86's wheelbase includes: Ground Control Camber/Caster plates on the front suspension and run max negative caster on the stock tension rod with poly bushings and max positive caster on the plates and extended the track length by about 2". Will measure it when I get a chance stock is 94.5" now my wheelbase is about 96.5".

You could extend the rear of the Corolla like you were thinking but only to a point. Past that you would need to either add to the driveshaft or have a spacer made to make up for that. If you don't I believe there would be too much stress on the differntial if you didn't do the aforementioned. Thus bringing up many new problems to deal with like an extended rear soft brake line, and clearance issues with the rear portion of the wheel wells.

Extending the wheelbase of the AE86 Corollas definately helps improves handling. By moving the Heavy end of the vehicle further apart from the Light end which slows down and reduces the body roll.

This is also highly sensitive to ride height, spring rate and suspension dampening along with other more complex dynamic supension geometry like center of gravity, roll axis, suspension natural frequency along with others.

1) While drifting you would feel the car transition more smoothly and kick out at a more precise rate. This will be most noticeable and useful on highly prepared vehicles.

2) While grip driving at wide track widths and softer compound tires you would feel a better progression to the point at which traction is lost.

I am using the car strickly for autocross with the occasional track day in the future. This setup I am running is actually working out very well as the Ground Control Camber/Caster plates are by far the most advanced design created for the consumer market for the AE86 chassis. They didn't advertise them on their site but they are available.

The placement of the stock rear Panhard Bar mounts will work well with rear springs between 8.5" and 9". Beyond that moving the mounts to keep the bar horizontal to level ground is needed for drift/grip driving. The rear wheelbase with a stock panhard setup can be extended about 2" without issue. A watts linkage taking the panhards place would be just about the best for all driving types.

I am also using a manual steering rack with 275/35/15 hoosier race tires and now l can keep up steering these sticky tires now because of the decrease in negative caster from the plates. The only problem is I cannot get full lock to lock out of the steering rack but there is only about 1" left though which isn't really used in autocross or track driving. This problem is due to the 10" wide wheels and 4" backspacing seen below.



-David

PS: I would suggest to all who wish to get the most out of their suspension switch all parts/bushings in the suspension to utilize spherical bearings/bushings. No matter what type of performance driving you plan on using your vehicle for this will keep the suspensions geometry as precise and predictable as possible. Not to mention alot easier to adjust and longer lasting to boot.

PPS: Sorry for the confusion in the original post I guess I was in lala land.

[Force_Fed]

What are we talking about here?

The post above I believe is referring to track width. I thought this was supposed to be about wheebase which is the distance between axles?

[landslideATX]

What are we talking about here?

The post above I believe is referring to track width. I thought this was supposed to be about wheebase which is the distance between axles?

yes. that is what i posted about. has anyone done this yet? does it make much of a difference in the way the car handles?

[Prime123321]

Updated my first post.

-David

[85levin]

it helps a lot. i am running maxed out t3 tc rods at 3.8 degrees caster. my front bumper had to be trimmed all around and my rear axel is also further back, rear bumper was slightly trimmed when i did the equal 4-link. i will be installing adjustable links soon and modifying my tc rods to extend wheel base further. i will post up if handling continues to improve or it starts to degrade. haven't measures my wheel base yet.

[Prime123321]

85levin + 1 for the equal length rear really helps out a ton adding more is almost always better to a certian point. While you are extending the cars wheelbase you can widen the F & R track a bit to help plant the car.

What type of driving are you doing?

If you are looking for a near optimum rear the Watts or Mumford linkage would be the best for laterally locating the axle. We hope to design a proper watts linkage for our Corolla as the one designed by SS Works albeit light years ahead of the panhard bar the center of gravity can be generously lowered by using a welded type at the lower rear portion of the axle instead. Not to mention the high price tag.

Also re-building/re-working the rear axle to have even the slightest negative camber would work wonders for in-turn rear traction. There are a few ways to do this on a solid axle and all will need research as I don't believe its for the faint of heart or daily driven cars. (Watch the wheel bearings)

Good Tuning,
David

[landslideATX]

it helps a lot. i am running maxed out t3 tc rods at 3.8 degrees caster. my front bumper had to be trimmed all around and my rear axel is also further back, rear bumper was slightly trimmed when i did the equal 4-link. i will be installing adjustable links soon and modifying my tc rods to extend wheel base further. i will post up if handling continues to improve or it starts to degrade. haven't measures my wheel base yet.

how far did you extend the rear end? what mods did you have to do to the pan hard bar? i have adjustable 4-links and pan hard already.

[85levin]

viewtopic.php?f=8&t=1972&start=15

my wheel base is 97.5 and hope to get it to 98 with the links. also, plan to add more caster in the near future.

i started road racing with the local pca club not long ago.

[landslideATX]

viewtopic.php?f=8&t=1972&start=15

my wheel base is 97.5 and hope to get it to 98 with the links. also, plan to add more caster in the near future.

i started road racing with the local pca club not long ago.

how did you end up getting around the panhard bar location?

[85levin]

i'm not sure i understand the question. i reinforced the stock pan rod mounting location on the body and lowered the diff mounting point. though, if i would have done it as a race car i would have lowered both.

[cdixon311]

I had spacers at one point to help with rubbing issues. It gave an extra inch on each side and felt pretty good actually.

[daveskatesallday]

I had spacers at one point to help with rubbing issues. It gave an extra inch on each side and felt pretty good actually.

that's what she said

lol sorry couldn't help myself on that one