grant
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Post by grant »

I have the RSR coilovers, so I'm pretty much locked in at 4.5.
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Post by kevin »

Grant, not been funny here but go buy a set of semi slicks. they are cheaper than your normal road tyres. You will be amazed what your car can do, its day and night. Just try it. i know you will say its bandage application but its another animal out there with different characteristics. I have stopped playing with suspension on my cars at this stage and now working on driving skills(or lack of) Get your castor to 6 as suggested.
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Post by grant »

Hey, is a semi-slick like a Toyo RA1, or R888? If so, I think we call them R-compounds in the states.

Anyhow, like I said, my caster is locked in at 4.5. I can't change it until I make a new UCA, which probably won't be for a while.

R-comps are definitely more expensive than my street tires, but they are next on the agenda. I'm hoping that once I have some income, I'll look into buying a set of light 15 inch wheels and perhaps 225/45/15 R888 if it is out in time or just the RA1's.

People have been telling me to upgrade tires for a long time, but I felt that until the suspension is optimal, I didn't want to waste tires or waste money that could go into developing the suspension more. Now, I'm pretty happy with the suspension (rolls a bit more than I'd like still) so I'm looking into tires.

UCA mod's should fnish up my development with the front suspension. If nothing will give me more camber gain, I'll just move on to the back of the car.

Thanks for your input.
PS, your track monster with a 24V and no interior will be much more of a handful than my 183bhp 2900lb sled. I'd be working on driver improvement too!
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Post by MR2 Zig »

What is the limitation imposed by the RSR setup? Are you having the UCA hit the coilover spring?

If I remember right Kevin had a RSR coilover setup on his car and had to open the hole in the UCA for appropriate clearance (he also did a bit of reinforcing around the opening). You may need to do the same to get the 6deg of castor.

hth,
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Post by grant »

I've removed a fair amount of material from the UCA to fit the RSR coilovers, but that was just to get it to fit. Because I have modified spindles, it doesn't fit as well as it would on the stock setup. Therefore, clearances are even tighter than normal.

Doesn't matter though, I just want more camber gain - I'll figure out how to rake the camber back when I go autocrossing again. Thanks!

I'll get a picture up of the front setup eventually.
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Post by Micke »

Do you really need more camber gain? How does your tire wear look?
How much do you have. With "dropped spindles" it is already improved a lot.
IMHO, if you don't have enought neg camber with that you'd be better off reducing roll. Then you don't fuck up the braking performance.
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Post by grant »

Tire wear seems to be on the out side edges, especially the rear tires (0 camber).

But, I'm getting the feeling knuckle risers have a definite trade off, where as dropped spindles do not.

105 guys were saying knuckle risers increased bump steer. Can anyone explain that to me? Is that just because the camber of the wheel is changing more?

If Barry or someone can produce knuckle risers for the 116 for cheap, I'd like to experiment with it. If not, I'll move on to other items (like paint and general maintenance :shock: )
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Post by Duk »

Hey Grant, after modifying my other 2 cars for more caster I noticed good improvements with almost zero negatives.
I know you wrote that you are caster limited, but I think that running a heap more any way you can will help enormously without reducing braking effectiveness. It worked very well on my Toyota MR2.
Alfa's lack caster, and lack camber gain. Lot's of rear wheel drive cars since the late 90's have bean using large caster angles. 6 degrees and more.
Last edited by Duk on Tue Nov 17, 2009 4:58 pm, edited 1 time in total.
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Post by Barry »

Sorry guys..one of those topics I completely missed...
Ill check today about the knuckle risers but agree with Carel,lengthen the bottom of the upright..

I believe RZ is sending me his SZ uprights ...hehe...! :D
French cars are shit and shit expensive to service and bloody awful and unreliable and expensive and friends don't let friends drive french cars and you wait years for parts.
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Post by Barry »

Grant,Bump steer is miles away from what knuckle risers are all about..I see no relation here..
Perhaps AFTER installing risers they then dropped the ride height..now this may cause bump steer problems...but that's also easy to overcome...
The best bet IMO here is the old thought of the upside down ball joint..
French cars are shit and shit expensive to service and bloody awful and unreliable and expensive and friends don't let friends drive french cars and you wait years for parts.
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Post by grant »

Barry, let me know about those knuckle risers!

I already have a 1 and 1/16th" inch dropped spindle and *under damped* front coilovers.

Barry, could you also measure the amount of drop on the SZ units, and see if there's any change to ackerman or anything else cool???
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Barry
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Post by Barry »

Ackerman is fixed,no change there...If I remember the SZ was 25mm longer..
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Re: Upper control arm angle mods

Post by PietereQ »

Ok spamming post today, but need to exploit that little free time I have. I guess I'll be running knuckles raisers. Sure not as good as drop spindles, but cost wise much more available for me atm and still better than nothing. Found the pics of autodelta knuckle raisers for 105 chassis. Now how much would you "raise" over the stock spindle?


Second question is, provided that I'll have the raiser installed, will I need to do any mods for the caster rod? The upper control arm will be way above the level, where caster arm is mounted into the inner fender, I thought of bending it downwards any other ideas?
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Duk
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Re: Upper control arm angle mods

Post by Duk »

PietereQ wrote:Second question is, provided that I'll have the raiser installed, will I need to do any mods for the caster rod? The upper control arm will be way above the level, where caster arm is mounted into the inner fender, I thought of bending it downwards any other ideas?
I have knuckle risers in my 75 (road car).

1st thing I will say is that I (personally) wouldn't use them over correctly made drop spindles if your car is lowered significantly.
I raised the front of my car up from the lowered state I bought her in. I'm guessing that she is lower than a standard 75, but far from the slammed 'drift slead wanna be' that the previous owner had her set to.
My LCAs are pretty close to horizontal when she is fully dressed (in pieces ATM).

I raised the front of my car more because of ground clearance issues than any other reason, but I do believe that for a significantly lowered car, well made drop spindles would be better suited.

I bought my KR from Vince Sharp here in Australia. He provides spacers, so that while the top ball joint is raised from standard (about 35mm I believe) the actual top control arm angle looks to be close to original for the ride height of the car.
My guess is that Vince added these spacers so that the front suspension doesn't end up with large amounts of static negative camber. The wheel alignment guy had to add a large number of shims just to get 1 degree of static negative camber.
I haven't had any issues with caster arms. But I also don't thnk that you would even if the spacers weren't fitted, and the top control arm was more in line with the 'actual top inner suspension pivot/top ball joint relationship'.

Hope that helps :D
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Re: Upper control arm angle mods

Post by PietereQ »

Hey thanks, but i cannot really see the knuckle rakser to be just 3,5 cm tall, more like 6 cm at least (just to allow some space for pivot nut)
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