Advice on Spring rates for 1UZ AE70 Corolla

[qagzie]

Hello Friends!

i just completed my 1uz ae70 swap (after 3 years)...heheh... Car is insane!!

i would like some advice on what spring rates are appropriate for my setup. engine is a stock 1996 1UZFE with a W57 and a hilux diff and 195/50 r15s. I intend to use the car mainly for street (racing)/ weekend driver.

Thanks

Max.

[Konakid]

I would start with something around the 5kg Fr and 3.5Kg rear and get a feel for it from there. 7 and 5 is normally good for drifting so the softer rates will be good for the street with bumps and also some squat for extra grip with the power level you now have.

[qagzie]

I would start with something around the 5kg Fr and 3.5Kg rear and get a feel for it from there. 7 and 5 is normally good for drifting so the softer rates will be good for the street with bumps and also some squat for extra grip with the power level you now have.


Thanks for your reply!

Considering the added weight of the 1uz, i was of the view
(guesswork) that perhaps i needed a slightly higher rate in the front...so i was leaning towards 7/5.... turns out it's more of a drift setup than street. Unfortunately, i had already acquired 5kg eibach springs for the rear.... was still saving up for the fronts...

So now I'll put them back in the box and try your recommended setup for starters..

How does a 6/4 setup compare?

Cheers.

[Konakid]

Dont overthink it. Run the 5kgs in the rear and see what you think. Get some 7kg for the front. with the heavier diff, gearbox and motor they will probably be ok, similar to a 6 and 4 setup. Will probably still be on the stiffer side for the street though. The 1uz is all alloy block too so it isnt as heavy as you would think. I had 6 and 4.5 in my corolla years ago and this was a good street setup, not too stiff but definitely on the limit for the street.. i then went to 8 and 6 and it was very stiff mainly good for drifting. it didnt like the bumps in the hills roads too much.

Make sure you get some good shocks to dampen the springs too

[qagzie]

Turns out that 5kg in the rear is waaay too stiff for any reasonable/enjoyable driving on street roads. Car is bouncy allover the place and has limited grip.

I'm thinking 3kg springs would calm things down pretty well.

Max.

[qagzie]

Turns out that 5kg in the rear is waaay too stiff for any reasonable/enjoyable driving on street roads. Car is bouncy allover the place and has limited grip.

I'm thinking 3kg springs would calm things down pretty well.

Max.

UPDATE

So, yesterday I installed a pair of 175lb hypercoils in the rear, (~ 3.1kg/mm) and instantly the car felt more balanced and also had better grip after taking it for a drive. What's left is just fine tuning the rebound on the coilover adjuster.

Cheers

Max.

[Konakid]

Nice! good to trial and error sometimes, even though it costs more at least you know now.

[qagzie]

Update:

So 3.1kg springs offer good grip and comfort on street roads, but only if I'm alone in the car. If I have someone in the passenger seat, the rear tyres scrub like hell especially when I'm turning. Not very good.

So... 4.5kg would be better all round.

Konakid you were right!

����

[Konakid]

Haha good to hear. Maybe just go a 4kg? an extra 1kg should be all it needs.

[qagzie]

Haha good to hear. Maybe just go a 4kg? an extra 1kg should be all it needs.

For real, i should do 4.5kg/mm just to rule out buying another set. :yeah: Is there a big difference in feel between 4 and 4.5?

[Sam-Q]

If the rear springs have too high a spring rate in proportion to the front then it will be more prone to oversteer. By fitting the 4 or 4.5Kg rears you may find that you will loose that balance you have now. I personally suggest fixing the actual tyre scrub issue instead of just trying to avoid it. I do find it odd that there is such a difference from having a passenger alone, well unless they really need to loose some weight.

You are running 4.5Kg in the front right now?

In the past on my AE86 I tried running 6kg front springs but the stiffness drove me crazy. I ended up choosing 4.9Kg / 275 Lb which I loved. But as you said the higher weight over the front end would have an effect on this, as for how much I have no idea.

[qagzie]

If the rear springs have too high a spring rate in proportion to the front then it will be more prone to oversteer. By fitting the 4 or 4.5Kg rears you may find that you will loose that balance you have now. I personally suggest fixing the actual tyre scrub issue instead of just trying to avoid it. I do find it odd that there is such a difference from having a passenger alone, well unless they really need to loose some weight. You are running 4.5Kg in the front right now?In the past on my AE86 I tried running 6kg front springs but the stiffness drove me crazy. I ended up choosing 4.9Kg / 275 Lb which I loved. But as you said the higher weight over the front end would have an effect on this, as for how much I have no idea.Thank you Sam-Q for your reply.

So I removed the 3.1kg springs and put back the 5kg ones for the meantime to stop the scrubbing. But to my surprise, the car feels so much firmer to drive. Even better than before.

Well, I've had some mods done...eg equal length 4 links, fitted pillow ball bushes on both ends of the panhard rod, coilovers [brand names faded off~ don't know who made them] etc. I admit I prefer how she feels now... but I'm still saving up for the 4.5kgs.

Unfortunately I don't know what rate the front springs have, but there's no scrubbing at all [car sits low] my guess is 7~9kg

Here's how she sits

38169

[davew7]

Max
That is one nice ride. You nailed it!!!!
Davew7

[qagzie]

Max
That is one nice ride. You nailed it!!!!
Davew7


:jdmsmile::jdmsmile: thanks Davew7.