The Toyota Strut King Pin Angle Database

[takai]

After going through all the threads and getting conflicting information abotu a whole bunch of KPIs for various cars ive cracked it completely and just starting again to measure my own. In a similar way to Wilbos method here im using a digital inclinometer like this one:


in order to measure the king pin angle of the strut.

Now i am making a couple of assumptions. One that the hub mounting face is essentially at 90° to the stub axle, and two that the impossibility of being exactly parallel to the angle of the mounting face (by virtue of the tubular nature of the strut) wont be a significant issue with the measurements. As such though all measurements in this thread might be out by say +-0.2° Keep that in mind.

So onto the measurements. This is how i do it:

Step 1

Place inclinometer onto the hub mounting face

Step 2

Zero the inclinometer

Step 3

Place inclinometer onto strut tube, try to get it roughly parallel to the mounting face, but in my testing a few degrees circularly off wont matter too much.

Step 4
Take a photo, use the macro mode on your camera, and try to take it off angle from the LCD. In that case i stuffed up.

Step 5
Post your result in here for everyone to be able to use. Try and use the formula below to inform your posts.

Onto the database
MX83

Inclination angle: 13.1deg

RA40

Inclination angle: 7.6deg

XT130

Inclination angle: 8.7deg

MA61

Inclination angle 10.6deg

TA22

Inclination angle: 8.5deg

Another thing to note, im measuring essentially the difference between the hub face and the strut tube. However, some people prefer to know the difference between the strut tube and the stub axle. In that case, just add 90deg to the angle given.

For those playing along at home
If you want to do some of your own to add to this thread, then follow the instructions above. In addition ensure that you know exactly what strut you are measuring. Its no good thinking you have a RA60 strut when its an RA65 strut. That sort of thing will just spread FUD (Fear Uncertainty and Doubt). Secondly, to play along, just go out and buy an inclinometer. I bought mine for $40 from ebay, but im told you can get them as cheaply as $25 from Bunnings (that same style), apparently they are in the chalkline and string section.

Good luck, and happy hunting.

[twentyEight]

Fantastic work Chris!

This will come in very handy for many... +rep.

[The Witzl]

Chris - post me your inclinometer and i'll measure my KE70 struts

also - it might be an idea to MS paint your database pics with the text that goes with them. It will make for easier future reference should the associated text be lost for each pic!

Like the example below:

[The Witzl]

also..... the lower the inclination angle, the greater the negative camber - yes?

[takai]

Yes, lower the inclination angle the greater the negative camber IF its the only thing changed in the system.

[The Witzl]

well when you are like me, looking for a cheap brake upgrade for your KE70/AE86 by just slapping in some struts... its handy to know what effect you are going to have on camber by swapping struts, and if you will need adjustable tops to correct any major changes.

[takai]

Yup, not doubting it at all. Just emphasising that you can only guarantee the numbers when its the only element changed in the system. Start swapping LCAs around too and everything goes wacked out. I know you know that Witz, but not sure if some of the newbies do.

[The Witzl]

Indubitably.

Perhaps you should also add to this thread a basic triganometric formula for calculating final CHANGE in negative camber based on the change in strut king pin angle and change in lower control arm length?

I'd do it myself now, but im at work and i get in trouble by my boss when i start jotting down maths formulas on scrap paper.

You work in marketing and product management, not engineering!

[takai]

Yeah, thats coming. Just need to find a good lineart drawing of the strut.

[The Witzl]

MS paint.

10char

[The Witzl]

Farkit..... i got tired of waiting, and was bored on teh weekend - so i took myself to Bunnings and bought a digital angle measurer (inclanometer) for the measley sum of $15.00

... and measured up my KE70 strut.

KE70 = 8.4 degrees

[takai]

Nice, i left my inclinometer at home today when i went to Upullit. Ooops.

[stahlz_ae86]

*subscribes*

May find myself at bunnings today, if so I'll grab one of those angle doobies and post up some AE86 and T-18 results.

[oldeskewltoy]

nice...........

Question.... none of these are known NOT to be bent...

I'm looking at the 3 that are very close(8.5, 8.7, and now 8.4) Are they actually the same????

Just a thought... having others duplicate your #s will help... say, knowing one = measured, knowing 2 = confirmed... or something like that.......

Great thread.... keep the info coming

[The Witzl]

could always just measure both sides and give both results?