RWD rear end and pinion angle q's

**Mr DOHC** · 13-05-2007, 03:31 PM

i just read that thread and hove no freaking idea what u just said

**chris davey** · 13-05-2007, 04:56 PM

Lucky you have IRS then

**Sam_Q** · 13-05-2007, 11:59 PM

sounds good, any chance of a picture of this neat tool you have to measure the angle?

**30psi 4agte** · 14-05-2007, 12:13 AM

I think its just your common school yard protractor.
They are not 100% accurate to use but can be with in a degree when used properly.

**-==L=a=N=c=E==-** · 14-05-2007, 07:06 AM

a protractor with a plumbbob on it at a guess.

**chris davey** · 14-05-2007, 08:50 AM

yeah I will get a pic. It is a magnetic thing with a circle on it with 360deg marked. Then it just has the plastic thing inside that can swing around and will always point to ground so you just line it up with whatever deg that is

**30psi 4agte** · 16-05-2007, 09:27 PM

Slightly off topic but.......

Is there any disadvantage / advantage to running longer upper control arms than you have at the bottom ???

Or will it make no difference as long as i work put the fore mentioned angles ??

The reason i ask is ....... I am currently also in the process of setting up my new diff and it is looking like my upper control arms will be longer than the bottom ones as it will provide a stronger mounting point this way.

**chris davey** · 24-05-2007, 08:27 AM

Sorry, missed this last question.

From my reading, there was one of those sites talking about that but they were talking about 7 second cars so I doubt it is going to be the same for you. Maybe talk to an engineer who has half a clue.

**stansr** · 24-05-2007, 07:28 PM

hey there,also correct me if i am wrong,but would different tyre sizes have some effects on the geometry on this these types of setups?

**chris davey** · 24-05-2007, 07:45 PM

well, for the program I was using it would as you have to input tyre diameter. Mine was 26" so it knows that the axle is half of that. Therefore if the lower mount is 11" from the ground it is 2" lower than the axle.

If I was to put a 22" tyre on my car from what I can tell it would then make the angles go up futher again. It depends how much the body moves when you change tyres. I know for certain that lowering or raising the body will definitely change geometry dramatically.

**stansr** · 24-05-2007, 08:09 PM

ok,had the feeling it may alter some geometry!. so does anyone know the best way or where to get adjustable control arms/materials,that allow adjustability and for you to retain the factory control arms,so that it is a bit more comfortable for street application.Can you just buy the threaded rod or tube and weld onto your control arms,just not sure which way to go about it,any ideas would be great,thanks

**RobertoX** · 24-05-2007, 09:34 PM

If you put on bigger wheels you wont really change the geometry but you will raise the cg slightly (you just raise everything by half the increase in wheel diameter) which will increase weight transfer to the rear which will be good for launching.

For adjustable control arms do a search around for "4 link kits" or similar, there are plenty of places that make these off the shelf for various applications. also for changing the angles of the arms look for "traction brackets" for more off the shelf stuff. Otherwise you can do it cheaply yourself if your handy with making things... although they might not be red anodised