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school me on lifts and geometry

Posted: Tue May 11, 2010 6:15 pm
by jbates58
hi all.

well the time has finely come to lift my faithful gq.

i am going to be going for a 3" kit, but i have a few questions and nothing in the search has really answered the question.

first off, i know that i will need coils, shocks, pan-hards, drag link (already have; superior) Castor correction (unsure whether im going to use bushes or dropped arms), extended brake-lines, and trailing arms.
But, Do i need upper controls as-well as the lowers? in order to correct the drive line angle.

also, what about the flexi kits, i know that you can run longer shocks, and have increased down travel, but does that mean i will need different length pan-hards, trailing arms, or brake lines?

and for the front, will i need longer arms to suit 3" or a different length if i go the flexi kit? will i need to use something like the flex arm?


cheers

jbates58

Posted: Tue May 11, 2010 6:33 pm
by Struth
You should post this in Gen Tech, you will get better answers.

Cheers

Posted: Tue May 11, 2010 6:33 pm
by oldmate
You only need the lower or the upper, not both to correct the driveshaft/pinion angle. Go with the lower arms as it will also re-center the wheel in the arch, when standing on a flat ground

you won't need anything extra for the flexy kits, if you have already got the longer panhards, and brake lines. The idea of the flexi coils as i understand it is to create a coil that is longer when unloaded to stop it falling out with big flex. THe adjustable superior links are suitable for any length from stock to about 6 inch of lift.

as for the front, if you're going to buy dropped arms, then you really are better off spending the coin on the superior flex arms just to get the big flex. Otherwise if you want to cheap out I would actually use drop boxes over castor bushes or plates as it will correct an aspect of the front suspension geometry that even dropped radius arms do not correct.

Posted: Tue May 11, 2010 6:38 pm
by DamTriton
Moving to Nissan tech where the knowledgeable will answer...

Posted: Tue May 11, 2010 6:50 pm
by jbates58
oops. OK. thanks damkia.


with the flex arms or even the drop arms, arn't they surposed to correct the same geometry as the drop-boxes, as-well as solve the issue with Castor? that is my understanding of them. and what are the flex arms like on road? as this is my daily aswell. i still have both sway-bars in, but as im airing down, i simply unbolt them before i hit the tracks so they don't limit wheel travel, and im able to fab up some extensions for them no probs.


cheers

jbates58

Posted: Tue May 11, 2010 10:19 pm
by coxy321
Front end castor solutions have been covered a billion times - my vote is for boxes, not arms, and definately NOT bushes.

Posted: Tue May 11, 2010 10:23 pm
by jbates58
also, i have a offroad camptrailer. a mate told me that the flexi's shouldnt be used for towing as they are not a load carying spring. whats the go with that?

and also, how about running polyairs in the lift? people are telling me that they will get pinched and bust.

and what are the componants from snake racing like? also, what other 4x4 offread suspension specialists are there?

cheers

jbates58

Posted: Tue May 11, 2010 10:39 pm
by jbates58
delete post

Posted: Tue May 11, 2010 10:42 pm
by coxy321
I can't answer the flexi-coil/towing question, but i know someone who can. Shane from suspension stuff can hook you up with any part from the "normal" major aftermarket suppliers. He could also sort something out with some rear flex and towing ability too.

Posted: Tue May 11, 2010 11:30 pm
by jbates58
will call suspension stuff tomorrow and see what i can arrange.

but, from my research, how does this sound?

front 3" flexis paired with superior super flex dropped radius arms, rear 3" HD standard (so i can run my polyairs) unsure of shocks at the moment. upper adjustable control arms, fixed length lower arms, adjustable panhards, and an extended brake line for the rear(i read that the rear one can be moved to the front).

how does this sound?

i figured that f i go normals in the rear, and flexies in the front, it might get the front to move a bit better. what do you think. after experienced opiniond, as i figured that a business will just try 2 sell it to me. could be wrong though.

cheers

jbates58

Posted: Wed May 12, 2010 9:10 am
by coxy321
jbates58 wrote:but, from my research, how does this sound?

front 3" flexis paired with superior super flex dropped radius arms, rear 3" HD standard (so i can run my polyairs) unsure of shocks at the moment. upper adjustable control arms, fixed length lower arms, adjustable panhards, and an extended brake line for the rear(i read that the rear one can be moved to the front).

how does this sound?

i figured that f i go normals in the rear, and flexies in the front, it might get the front to move a bit better. what do you think. after experienced opiniond, as i figured that a business will just try 2 sell it to me. could be wrong though.
Make sure the rear lowers are HD, and also lengthened to suit the lift (maybe 10-15mm?). Everything else looks good though.

Do you have, or are you keeping sway bars? If you're keeping them, you may need extension links with a quick release. I'm looking at getting swaybars on my car now cause its too rolly.

Posted: Wed May 12, 2010 10:12 am
by jbates58
yeah. I will b keeping the sway bars in 4 more stability on the tarmac, and ill just fab up some extentions with disconects 4 them.

And the lowers will deff be heavy duty.

Cheers

jbates58

Posted: Wed May 12, 2010 10:12 am
by 5inchgq
I run a 3" lift in my GQ LWB and have superior adjustable lower rears, draglink and super flex arms the main drama I have is the radius arms have no sway bar option (superior will now drill and tap these holes at customers request). So I run a rear sway bar and on road it seems to be a bit boat like (no real dramas just the difference is noticable after running standard arms and castor bushes). The other thing to be aware of is to get the spring rates right I'm on my second set of dobinson front coils as the last set I had were too stiff and and the front end flexed less than standard!! Sounds like you are on the right track ......enjoy!

Posted: Wed May 12, 2010 1:07 pm
by gu town
i have the 3in flexy kit with drop boxes and normal springs in the front. i really like it. going from a 6in with drop arms. i have a big heavy steel tray and canopy also and the extra heavy duty rear flexy coils handle it well.

the only thing i could possibly knock about the kit is that my front springs have settled slightly lower than i'd like them to have.

definatley call shane from suspension stuff. had alot of time for myself and made sure you've got the right gear, not just getting sales.

b

Posted: Wed May 12, 2010 4:32 pm
by Clanky
To get around your flexi spring / towing issue, you can have two different sets of rear springs.
One for your normal work and another set of HD ones for the towing trips away when you are loaded up. Just swap them over.

GQ coils are easy to change over, and if you dont want to do it, any garage can have it done in about 15mins (probably less) on a hoist

Re: b

Posted: Wed May 12, 2010 4:49 pm
by jbates58
Clanky wrote:To get around your flexi spring / towing issue, you can have two different sets of rear springs.
One for your normal work and another set of HD ones for the towing trips away when you are loaded up. Just swap them over.

GQ coils are easy to change over, and if you dont want to do it, any garage can have it done in about 15mins (probably less) on a hoist

lol, so that idea isnt as crazy as it sounds;i had thought of that. lol. but when im towing, its to go away 4wding. i dont own a boat or trailer, just my offroad camper. i dont imagine that it would be to easy to do on the ground, at a 4wd park. or the driveway at home.

and yes, i know that the topic of drop boxes vs drop arms has been discussed a million times, but there seems to be no definitive answer as to which one is better. i personaly like the idea of the arms, from what i can gather, they do the exact same thing my standard arms ar doing, but they are suited to the lift. my understanding is that drop boxes just lower the mount point to keep the geometry the same, and then you use neutral bushes for the castor, where my understanding of the arms is that they have the castor and the drop inbuilt. so it seems a little senceless to go for the boxes over the arms (funds permitting) as they just sit below the chassis, and they are easier to notice for the DOT and others.

please, correct me if im wrong.

cheers

jbates58

Posted: Thu May 13, 2010 8:18 am
by gu town
while dropped arms are good they still don't completely restore the geometry. (on compression your front wheels still have to go slightly forward to go up. where as drop boxes with the arms flat your wheels go up and back) but, as mentioned drop boxes may (not that they have for me) attract the wrong attention.

having two sets of springs would be useless unless you changed shocks as well. the idea of the flexy springs is to run longer shocks. the normal springs would just fall out and being stiffer springs for towing, if you went up a gutter or steeper driveway wrong with the van or whatever un hitched you'd find yourself chasing a coil down the road.

Posted: Thu May 13, 2010 11:03 am
by jbates58
thats true. Ive had 2 put springs back in a mates after it popped out at the glasshouse. Not an easy job, even with that side at full extention. I dont even wana think how hard itl b with a jack on the road. Lol.

And i spose that makes more sense. What are the radius arm spacers for? What do they do besides space the arm forward? Are they similar to using extended arms?

Cheers

jbates58

Posted: Thu May 13, 2010 11:26 am
by gu town
spacers are to push your diff forward, people who use castor plates use them. most dropboxes and radius arms have it built in.

usually only 10-20mm, just to clear tyres from the back of your guards and, to an extent improve your approach angle.