How much does offset affect alignment?

Wheels, Suspension, Brakes & Tyres questions and answers

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Sheck
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How much does offset affect alignment?

Postby Sheck » Mon Apr 24, 2006 9:47 am

I just got some bolt on spacers on my car recently, they are 25mm and the wheel is a +40 which makes it a +15 (sits relly flush and looks great!)

I put them on cause i figured the increase in track would give me better front end grip, but at the recent drift day i was getting massive understeer. :cry: And no i didnt bother pulling them off to see if it was them, cause i just wanted more track time :mrgreen:

So i was just wondering if this could be due to the increased track, or if its my tyres or if i just need to drive it harder to keep the tail out?

So if any of the race guys or anyone with an answer could help me that'd be great!!

Thanks
Last edited by Sheck on Mon Apr 24, 2006 10:15 pm, edited 1 time in total.

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Matty
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Postby Matty » Mon Apr 24, 2006 10:41 am

They don't affect the alignment per se, but they will affect things like scrub radiuses, weight transfer, steering feel, etc.

Without back to back comparison (as you say) it's hard to tell what the cause is...

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CT
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Postby CT » Mon Apr 24, 2006 8:53 pm

We have found that there is an increase in grip when widening the track using spacers. You might have increased rear grip more than front grip if it induced understeer.
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Postby Babalouie » Mon Apr 24, 2006 9:22 pm

I run +15 wheels and yes it does dull the turn-in, the mid-corner grip is stronger from the wider track (but as CT said).

Try running a smidge of front toe-out, in my case that brought it all back to normal.
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Sheck
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Postby Sheck » Mon Apr 24, 2006 10:15 pm

i've only put the spacers in the front, so i figured it would of been awesome front grip compared to the back, turn in wasnt affected too bad i found that after initiating the drift into the turn, at about half way into or just before, i would still have positive lock on and the front would just lose traction and send me into the dirt very very frustrating!
And yea i run 1mm toe out on both sides.

My power steering pump is pretty much stuffed too, and the whole time i wouldn't have any assist so i was fighting the fluid and the tyre to turn the wheel, so that did dull my steering reaction a bit.

Thanks for your answers guys, hopefully it'll feel better on sunday (drift practice day) with some more practice.
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Postby devolutio » Fri May 26, 2006 11:43 am

I have found that when changing the offset of front wheels, the thing that is affected the most is the self-centering of the steering. This might not be as noticable with your power steering, but with my ae86 it meant that i had to try and dial in the right front wheel angle entirely with my hands, whereas before with stock offset wheels I would just let go of the steering wheel and then catch it again (or on long handbreak entries wind opposite lock in slowly, but it almost drives itself).

What is your castor set to? If you are into drifting it might already be maxed out... but if it isn't I would recommend it.

In an underpowered car (comparing to turbo nissans) castor is the most important aspect in my opinion. The next time I went out with castor wound right up I had a ball!

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Sheck
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Postby Sheck » Sat May 27, 2006 8:56 pm

hey yea, it ended up being a missing bolt on one of the brackets holding down the steering rack, when i turned the rack would lift and hten turn the wheels. Fixed that, and now all that is causing my understeer is the soft (to soft for drift) suspension, it'll nose dive and roll at the worst times and casue a bunch of under wich forces me to put positive lock on and just as i catch the under in time it lifts and i spin if i dont catch the lift in time - if you get me

Pretty annoying either way, plus i need a new clutch as mine can't handle 12psi - gave it some curry in 4th today and from about 4.5-5k it started slipping - not cool.

As for castor i can only get 5-5.5 with my current setting of -1.5 camber, but that will change when i get some new bushes (offset bushes to give max camber and set castor to 7-8deg prefferebly).

Didn't find self steering a problem because i'm constantly moving the wheel in most slides and in the big manji's i dont really have a problem with the car correcting it's self. Plus i've pulled my power steer pump off now so it's feeling alot better than before.

Cheers!

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Re:

Postby Moggy » Fri Jun 23, 2006 11:28 am

Sheck wrote:As for castor i can only get 5-5.5 with my current setting of -1.5 camber, but that will change when i get some new bushes (offset bushes to give max camber and set castor to 7-8deg prefferebly).


Hey Sheck, where do you get those bushes you are talking about as I need a new set of rear bushes to bring the camber in a little. The stock ones don't come in enough as my car is a bit lower than standard, and I wasn't sure if aftermarket ones were available.


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