Suspension:

07-11-02 - I went to my favorite junk yard and found a Toyota Corolla GTS (AE86). I pulled the struts off to upgrade my Starlet.

- Installed rear shocks from a AE86. They are used and I think they are stock shocks. They looked new when I pulled the ae86 rear so I got them. I drives much better but that is probably due to the original shocks being shot. As a note the shock is about 2" shorter fully extended. After a few really tight circles the shocks didn't top off so I figure the set up is ok.

There are 2 approaches to doing this swap

1. The KP61 steering arm attachment holes are to close together for an AE86 strut. So a a thick adapter that allows a KP61 steering arm to bolt to a AE86 strut is needed. Someone was making and selling these on Toyota Starlet Racing Group. Another aspect of this adapter is that since it's thick it will act as a roll center adjuster (realigns suspension geometry on lowered cars).
2. The AE86 steering arm's lower ball joint hole is too large for a KP61 lower ball joint. So a tapered bushing needs to be machined to take up the slack.

The second approach is what I am trying. I've dropped off my parts at a local machine shop and I'll post my results when finished.

01-03-03 - AE86 struts on my KP61:

- Prepared Struts : Cleaned and painted parts. Repacked wheel bearings. Assembled AE86 Strut with Stock KP61 springs.

- Installed Struts: AE86 steering arm with tapered adapter bushing on KP61 suspension. Removed sway bar to lubricate bushings and droop the suspension to aid in installing the struts. Bellow I a picture of a stock KP61 steering arm (top left), an AE86 arm with bushing installed (bottom left), AE86 arm without bushing (bottom right), and one of the brushings on it's own (top right).

- Bleed brakes, adjusted alignment as best I could, and test drove.

Results :

- There's more dampening up front. Since the stock springs were used it still handles pretty much stock. The chassis height is confusingly the same or possibly lower. I measured from lower suspension arm chassis mount to ground as per Toyota Service Manual and it's about 8½ inches (stock is about 9 inches). Also I cannot fit my floor jack with a wood block jack pad under the cross member anymore. The AE86's spring perch measured about 3/8 of an inch higher then the stock starlets so my only explanation for the lower ride height is the camber.

- You can compare the last 2 pictures bellow and see a difference in camber and even a difference in track. The last one is stock and the others are with AE86 struts. The front track seams to be about 2 inches wider then the rear. If the camber is adjust at the strut top this wider track would be a match to the 2 inch wider AE86 rear end.

- The Starlet center caps don't fit anymore but the wheels are only temporary.

- I am still using the KP61 Master Cylinder to run the front AE86 brakes. There is more pedal travel and it's hard to tell if it stops faster.

01-11-02 - The current AE86 struts with KP61 springs don't work well. I'm hitting the bump stops. I think it's because the AE86 strut has more case above the spring perch. I've ordered new suspension components. Tokico shocks all around, Ground control coil overs with camber plates and battle version roll center adjusters up front. I still need to figure out what to do with the rear springs.

01-21-03 - Well, parts are still slowly coming in. Bellow measurements are from mount to mount as shown in the pictures.

Front : The AE86 case is longer then the KP61's so it will have to be shortend just to get stock suspension travel at stock height with stock spring rates. They will need to be shortened beyond the starlets struts length to get a decent amount of suspension travel. I can also shorten the bump stops for some more travel. I need to make sure to not let the strut inserts bottom out. I want maximum suspension travel at about a 2 inch lower ride height so I can run lower spring rates and soak up some ruff roads as well. Just waiting for all the peices to be in front of me to do the final calculations.

Front Strut Insert	Maximum		Minimum		Travel		Static
KP61	22_5/8"	575mm	15_7/8"	403mm	6_3/4"	172mm	19_1/4"	489mm
AE86
BZ3099*	20_7/8"	530mm	13_15/16"	354mm	6_15/16"	176mm	17_13/32"	442mm
*Tokico Illumina part number for 88-89 MR2 supercharged rear strut insert application. Note - "Static" is strut length at 1/2 travel; the length of the strut as it should be installed.

Rear : I figure a 2 inch lower ride height is what I'm going for. The AE86 shocks would have been perfect but I could not find a shock I liked for the rear of the AE86. Seams allot of shocks have been discontinued for the back of the AE86. I was also considering shocks from a Camaro but I was concerned they would be to stiff and even if adjustable the adjustment would most likely be only increased stiffness. My decision came down to RX7 rear shocks said to work well with the MR2 struts witch are said to be a bit to soft. I figure getting the Illuminas that adjust compression and rebound would allow me to turn up the stiffness if I did agree they were to soft. One compromise with the Illuminas is that the compression and rebound adjustment cannot be adjusted separately. The limited applications and price of independently adjustable shocks were key factors in my decision.

Rear Shocks	Maximum		Minimum		Travel		Static
KP61	25_1/4"	641mm	16"	406mm	9_1/4"	235mm	20_5/8"	524mm
AE86	23"	584mm	14_1/8"	360mm	8_7/8"	224mm	18_9/16"	472mm
BE2317*	21_3/4 "	552mm	14"	356mm	7_3/4"	196mm	17_7/8"	454mm
*Tokico Illumina part number for First Generation RX7 rear shock application. Note - "Static" is shock length at 1/2 travel; the length of the shock as it should be installed.

General Suspension Comments : Some people swear by Koni. However, from trusted and honest sources I learned Konis are great... ...on the track with an experienced driver behind the wheel. To a novice (witch is me) Konis would be a hand full since there valveing is for ultimate grip but causes violent and surprising loses of traction (to the novice anyway). Other shocks TRD, tokico, and some others are said to have valveing that allows predictable loss of traction hence my decision. For my application, unsupported by aftermarket, mixing and matching parts, needing some adjustability because of the unknown results, being a novice racer, driving mostly on the street and occasional autocrossing I came to my choice. For more shock measurments visit Garage Dori's tech section Shock Guide page.

01-26-03 - Suspension work.

I modified the shock tower to accept Ground Control camber caster plates and adjusted to less that 1 degree of camber and no caster change. Ground control included a template to make the car for cutting and drilling. I cut the adjustment space differently then the template and installed the slider mount backwards in order to move the strut 1 inch outwards (removeing camber gained from AE86 struts). To note it is much easier and more accurate to cut the lip off the strut hole first then tape down the template for marking.

So the current set up is:

Front: 300lb/in (about 5.3 kg/mm), stock AE86 shocks and ½ AE86 bumpstops.

Rear: Starlet springs with 1¼ coils cut, stock AE86 shocks, ½ Starlet bumpstops. I cut the coils from the bottom of the spring. This caused the spring to slip off the bottom perch. I welded a tab across the front of the spring perch to prevent this (I was itching to use my new welder anyway).

Results: It rides 2 inches lower front and rear. It's difficult to see the drop in the bellow pic (left side stock right side lowered). However the move towards stock camber in the right pic is noticable (gain by installing camber plates previously discussed). In the right picture you can see more tread showing at the top of the tire. The front track is 2 inches wider, a perfect match for the t283 rear end to be installed later.

The rear cut springs seam to soft. At the 2 inch lower ride any spirited driving makes the rear suspension bottom out. The front however seam to be stiff enough to prevent any bottoming but soft enough for my personal comfort. As I explain before about Koni shocks not being the best choice for a novice, really stiff springs are not the best choice for a novice. While stiff springs allow a lower ride height and flatter cornering to a novice softer springs are better becuase they make weight transfer seam much more obvious. I think the 300lb/in rate are a good match for my novice racing abilities.

I also modified the Tokico Illumina RX7 shocks I plan to install later. I drilled out the RX7 rubber mount and installed rubber mounts from my old Starlet shocks.

01-30-03 - Installed Battle Version roll center adjusters (RCAs) also known as bump steer reducers. They go in between the steering arm and the strut. The point of this parts is to angle the steering rod back to stock. Without this you'll get an unwanted turn when going over a bump (suspension compresses). This is bump steer. It is not good.

03-07-03 - Nothing really done but I am looking into rear springs. I already have rear shocks that I like. I don't like the idea of clamping or welding perches to them. It leaves be to either make some sort of bracket that could weld to the eyelet and not the pressurized oil filled tube or just get custom springs. I've ordered springs intended for dirt track/ circle track cars that are very close to the spec I want. They should fit on the perch, be very close to being captive and are available in many rates. Hope to get these next week.

03-11-03 - Got some spring in made for dirt track cars. They physically fit on the perches but due to a miscalculation the car is not low enough. I used the entire weight of the rear of the car to calculate the compression of one spring. I should have divided the rear weight by 2. Not a big worry as shorter springs are available that should give me what the ride height I want. The picture on the left shows how the springs fit on the rubber insulator. The picture on the right shows how the springs fit on the lower perch.

03-13-03 - MR2 rear strut inserts into AE86 front strut housings.

Disassembly - Getting a 15 year old gland nut off can be difficult. But nothing a big wrench can't handle. Once gland nut is off taking the "O" ring in the picture bellow needs to be removed in order to pull the stock shock guts. By the way they are filled with oil so it can get messy.

Installation - I shimmed the strut insert up so the gland nut would tighten it in place.

Gland nut woes - The gland nut that came with the MR2 strut inserts are a different thread then the AE86 thread. So I figured I'd just use the AE86 nut. After removing the seal from the factory gland nut I found out it didn't fit the new strut insert. So I bored out the inside of the nut and tapered the edge with a die grinder and bit. 22,000 rpms of flying metal fun later it fit the new strut insert.

05-08-03 - Shortened struts during the past 2 days. The ground control adjustable perch bolt seized and the allen rounded off. I had to drill it out and use an easy out to take out what's left. The head of the bolt is so snug in the collars cavities any small amount of corrosion seizes it up. I bored the whole out a bit and used some anti seize on the bolt on the other collar. I still need to get a new bolt and adjust ride height. In the picture bellow it is sitting 3 1/2" (89mm) lower then stock in the front and 2" (51mm) lower in the back. I just had to see how low it would go.

05-09-03 - Got new hardware for the ground control adjustable perches. Adjusted to 2 inches lower up front.

08-XX-03 - Coilover and shims and springs. Oh my.

Installed T3 rear coilovers. (pics and details to come later)

Made coilover shims from old Chinese food containers. Why? to prevent metal to metal contact of the spring to aluminum perches. Plus the plastic provides a slicker surface when adjusting the perch.

The picture bellow is of a briefly used QA1 spring (silver) compared to a used Eibach spring (maroon). After a few test drives the QA1 spring rubbed on the threaded potion of the coilover and is now curved. I have yet to run into this problem with Eibach springs. Also the QA1 is 10_1/4" tall and the Eibach is 10" exactly. As a side note the QA1 springs only come in 50lb incremenets. Eibachs come in 25lb increments. The QA1's from a local speed shop cost about $15 less a pair.

08-22-03 - The TRD Starlet cup cars ran equal spring rates front and rear but had added a rear sway bar. I Installed 175in/lb springs front and 200in/lb springs rear. I have a higher rate in the rear to make up for not having a sway bar back there. Also front ride height is set to 1_3/4 lower and rear to 2_1/4 lower. After test driving the car feels more balanced. Still not quite right.

10-17-03 - More suspension tuning.

Alignment: Finally got an alignment. After getting the bill I decided to develop tools to check it on my own. I hope to develop tools to reproduce the alignment shops measurements.

Front: I Installed longer threaded coilover sleeves. The strut is threaded all the way down to the brake bracket now. I can now fit 10" springs and helpers to keep everything aligned and captive during jacking.

Rear: I've removed the rear coilovers due to interference problems. Once the AE86 differential is installed there will be more room because the shock mounts are outboard of the Starlet's. I have temporarily installed stock cut springs.

Driving impressions: about -1°camber, stock toe and caster. Front 200lbs/in, 1.5" lower, shocks at 1/5. Rear cut springs (softer than 200lbs/in) 2.5" lower, shocks at 2/8. Grips well and is solid but comfortable. Haven't really pushed it but feels balanced during spirited driving.

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