Interested - can you live with one

[427James]

I have a z06 vette, after having a Cerb. I am fairly mechanical and I have a rough idea with push rod chevys, so naturally I am massively interested in Ultimas.

THe question is, can you get one over a speed hump without taking the nose off it?

James.

[Pb3]

No probs, providing the speed bump is within spec. Six months before completing my build the council installed "speed cushions" and a raised zebra crossing at the village boundary, I was well chuffed to say the least. But I soon found that they were not an issue nor are others.

[Steve_D]

Department of transport regulates speed bumps and they must not be higher than 100mm. Most councils don't exceed 75mm so people cannot complain as they are well in spec.
An Ultima set at factory ride height of 106mm under the front axcel will not have issues but could be set higher if you had issues in your local area.

Steve

[TuxMan]

Yep no problems as well as the 106mm ride height the short overhangs help too although the dropped flour can sometimes be a issue . simon

[actuary]

Telford council have some monster speed bumps - If the 100mm limit is a UK wide regulation I may fire off a letter or two (for what good that will do !).

Does anyone find that the speed bumps scrape off the head of the seat fixing bolts ? I guess that you don't want to approach one on the brakes as the front will "dive", the 6mm gap doesn't seem that much ! No doubt any contact at the front would cause huge damage to the front canopy !

Does anyone have any devices fitted at the front "just in case", say like a thin sheet of ally under the GRP that can take the brunt of any oversize bumps ? Also, has anyone been on a cross channel ferry with their Ultima ? Any scrapes or otherwise ?

Regards

Tony.

[Pb3]

Another thing to watch out for is undulating roads. I recently whacked the sh!te out of my chassis rail that sits under the sump, as I came off a peak at speed the suspension compressed just in time to hit the next rise in the road. Not a pleasent feeling at all. Looked underneath to see a lot of paint missing, heavy scoring and a dent to one side. To be fair the road I was on is very bad and most cars struggle with the bumps and some of the bends for that matter. Our local garage wrote my wifes car off, doing a 'test drive' down the same stretch!

[andygtt]

I had 93mm under my front clip (as I had 16in wheels front) and whilst I was always careful I only ever had problems with kerbs..... if you have one with 18in wheels it will have over 100mm+ so should be no problem if you are careful.

[TuxMan]

Been to le-mans in the can-am and had no problems with ferry ,the ferry guys were very good with extra planks etc . Simon

[ezakimak]

If you fitted 19’ wheels and tyres of appropriate size what would the ground clearance be.

I have been trying to calculate this allow with the circumference for gear calculations but seem to have my formula wrong – as I cant get the 18” wheels to match up to values posted hear previously either ?

Ryan

[Steve_D]

ezakimak said:

If you fitted 19’ wheels and tyres of appropriate size what would the ground clearance be.

I have been trying to calculate this allow with the circumference for gear calculations but seem to have my formula wrong – as I cant get the 18” wheels to match up to values posted hear previously either ?

Ryan

If you fitted 19" wheels and bigger tyres they would not fit the wheel arches.
If you fitted 19" wheels and lower profile tyres to keep the diameter the same then there would be no change at all to the ground clearance.

If you want more clearance then just adjust the spring seat on the shock absorbers.

Steve

[andygtt]

19inch rims with lower profile tyres to fit the ultima arches would ruin the ride and handling... you can't increase the rr of the wheels as the 18's are already on the limit especially on the front.

My car had 16's on the front and a smaller rr which meant a lower ride height at the front.