Vitara 1.5" lift spacer kits

I've just highlighted some major issues with a well know supplier of lift kits, I do hope they pay attention as it's not the first spacer type kit I've had to rectify (which came from a lesser known supplier) - luckily the last one I fixed was ABS plastic spacers so easily machined to the correct length, but the ones I'm looking at are a Shore 90 grade PU so are difficult to machine (but not impossible).

The supplier of the ABS kit's response was "that's what everyone else sell" - well clearly, 2 or more wrongs do make a right then eh?

My message went something like this, I'm hoping it made sense and hope to educate potential buyers NOT to buy miss matched kits, it might not kill anyone but you're not getting the most out of what you ordered and it WILL smash itself to bits pretty quickly.

Anyway, here's the main fat of the theory:

"Have you considered that the design of the front suspension on a GV requires a shorter strut spacers and significantly shorter spring spacers than the rear live axle.

I'm not confident this has been considered, it looks to me like the spring spacers in the photo are all 38mm

This is fine for the rear axle as the springs are mounted almost at the axle center line - so measuring from the pivot point on the chassis, to the center line of the wheel, and then again from the pivot point to the centre of the spring and dividing the first by the last equals the ratio (lets say off the top of my head (1200mm/1200mm = a ratio of 1, so 38mm on the spring, equals 38mm on the lift)

The front suspension is very different. The shock is mounted inbound of the wheel, and the spring is even further inbound along the "arm" which is no longer a radius arm, and is now a wishbone - the same measurements apply, from the pivot point on the chassis, to the centre of the wheel, divided by the centre to centre (pivot point to damper center) lets say again off the top of my head I think the arm to wheel (center) is about 650mm?, and the arm to shock is about 550? (I'm guessing from visual memory) so the ratio is 1.18 given those numbers, so 38mm on the shock will be suitable for a 45mm lift at the wheel! (38 x 1.18)

The spring centre point is even further inbound - VERY inbound in fact, so 650, divided by 250 lets say? gives a ratio of 2.6!!!!!!!!!!!!!!!! so a 38mm spacer on the spring will lift the car nearly 100mm of lift at the wheel!!!!!!! (minus a small, small amount for sagging - maybe)

working those numbers backwards, to lift the car 38mm you'd want 38 divided by the spring ratio of 2.6 so it would be about 15mm spring spacer (add a mm or 2 for "sagging" but not much, trail and error here without doing some very complicated maths)

And the shock, would be 38/1.18 so about 32mm spacer would be correct."

This is roughly what a properly matched front kit should look like people of BigJimny - I don't think the suppliers will love me and they'll probably hate me for telling them but this is just how it is, its a matter of fact situation, there aren't to many ways to tell someone they're wrong without it sounding cocky :blink: (ok, and it does annoy me a bit, but only because I've had the sh!tty end the stick righting the wrongs )

Russ-41 wrote: I've just highlighted some major issues with a well know supplier of lift kits, I do hope they pay attention as it's not the first spacer type kit I've had to rectify (which came from a lesser known supplier) - luckily the last one I fixed was ABS plastic spacers so easily machined to the correct length, but the ones I'm looking at are a Shore 90 grade PU so are difficult to machine (but not impossible).

The supplier of the ABS kit's response was "that's what everyone else sell" - well clearly, 2 or more wrongs do make a right then eh?

My message went something like this, I'm hoping it made sense and hope to educate potential buyers NOT to buy miss matched kits, it might not kill anyone but you're not getting the most out of what you ordered and it WILL smash itself to bits pretty quickly.

Anyway, here's the main fat of the theory:

"Have you considered that the design of the front suspension on a GV requires a shorter strut spacers and significantly shorter spring spacers than the rear live axle.

I'm not confident this has been considered, it looks to me like the spring spacers in the photo are all 38mm

This is fine for the rear axle as the springs are mounted almost at the axle center line - so measuring from the pivot point on the chassis, to the center line of the wheel, and then again from the pivot point to the centre of the spring and dividing the first by the last equals the ratio (lets say off the top of my head (1200mm/1200mm = a ratio of 1, so 38mm on the spring, equals 38mm on the lift)

The front suspension is very different. The shock is mounted inbound of the wheel, and the spring is even further inbound along the "arm" which is no longer a radius arm, and is now a wishbone - the same measurements apply, from the pivot point on the chassis, to the centre of the wheel, divided by the centre to centre (pivot point to damper center) lets say again off the top of my head I think the arm to wheel (center) is about 650mm?, and the arm to shock is about 550? (I'm guessing from visual memory) so the ratio is 1.18 given those numbers, so 38mm on the shock will be suitable for a 45mm lift at the wheel! (38 x 1.18)

The spring centre point is even further inbound - VERY inbound in fact, so 650, divided by 250 lets say? gives a ratio of 2.6!!!!!!!!!!!!!!!! so a 38mm spacer on the spring will lift the car nearly 100mm of lift at the wheel!!!!!!! (minus a small, small amount for sagging - maybe)

working those numbers backwards, to lift the car 38mm you'd want 38 divided by the spring ratio of 2.6 so it would be about 15mm spring spacer (add a mm or 2 for "sagging" but not much, trail and error here without doing some very complicated maths)

And the shock, would be 38/1.18 so about 32mm spacer would be correct."

This is roughly what a properly matched front kit should look like people of BigJimny - I don't think the suppliers will love me and they'll probably hate me for telling them but this is just how it is, its a matter of fact situation, there aren't to many ways to tell someone they're wrong without it sounding cocky :blink: (ok, and it does annoy me a bit, but only because I've had the sh!tty end the stick righting the wrongs )

Basic trig. You'd think that sort of thing would be taken into consideration but well obviously not..

OllieNZ wrote: Basic trig. You'd think that sort of thing would be taken into consideration but well obviously not..

I'm really hoping that their photo's are just misleading and I end up with copious amounts of egg on my face!

- but the description suggests the spacers front and rear and the same size, so who knows

Most kits like this are going to be based on what I (Bits4Vits) developed eight years ago and originally sold...

I always pointed out that more lift would be achieved on the front due to the geometry of the suspension, and as you point out the front spacer is inserted onto the top of the front spring which indeed is 'half way' up the wishbone, and not at the end like on the trailing arm on the back...

BUT, Vitaras do normally sit front end down a little, and, there is more spring fatigue / sag on the front due to the extra weight of the engine at the front, and usually front driver and passenger, and not so much weight in the back...

SO, fitting equally sized spacers front and rear gives a Vitara / Grand Vitara a nicely even levelling lift, and the vehicle sits nicely like this...

I've sold literally thousands of these spacers, and have never had any complaints...

As I kicked off above, many of the spring spacers sold today are based on my 38mm design... as I (still) believe that if you want to get more lift than this you should be fitting lift springs and not spacers... 50mm spacers on a Vitara is defeating the object, it will just compress the spring and give no more lift, just solid suspension and very little articulation...

But then, I've only been messing with Vitaras for 22 tears, so what would I know...?

Dave, Bits4Vits

This is Bob the Vitara, an early plaything and development vehicle -



He just had a basic lift made of equal height spring spacers all round, front strut spacers and rear shock extensions...

See how he sits equal height front and rear, nice and level...



Good for offroading on a budget, back in the day...

Dave,

I appreciate your response, I think we had this discussion over a year ago privately (the kit in question I was working on was not yours, we were just casually discussing it, I don't recall when or where?)

As I said, I little trial and error required as the calculations are pretty extreme and to many errors would be accumulated trying to measure parts and estimate weights and leverages etc.

I tried fitting a 2" spacer kit and the extended shock topped out with 2.25" shock spacers, the lift was over 100mm, it was just silly, and extremely annoying. just to re-iterate, this was NOT one of your kits.

I'm just a design engineer working in R&D, contracting for the likes of BMW and others I can't mention.... what would I know? :silly: