Jimny Fox suspension

That js adventure class. Have a lot of speed but also have heavy off road on some of stages...

Stock shock fwd are 4 " travel and rear 6" travel. When jnstall +3" lift kit that have to be as per calculation 7" forward and 9 " for rear shock if i am not wrong. What is your opinion?

What amount did you extend your bump stops? To get a shock with the most available travel on stock components, you would want a compressed length of about 12.5 inches for the front. It would be about 14 inches for the rear. If you have extended the bump stops by 2 inches, you would want something with approximately 14.5 inches compressed length in the front and 16.00 in the rear. From there you can look at6 what shocks have those compressed lengths and 8 and 10 inch travel. I am looking for the list I have.

Some stages have speed like on rally raid but some of them have heavy mud and sand. So i have to find solution what will be best setup to cover everything...

You and Lambert beat me to a reply. Bump stop extension length?

I have hydraulic bump stops 4" by Terrafirma.

4 inch stroke or 4 inches of extension when compressed?

4 inches stroke

Zukebob, I’m interested to know why you think poly bushes will allow more travel than standard rubber? I’ve always found the polybushes much stiffer than the standard rubber ones. The ones with the gaps are best and are always better with a bit of wear and best just before they fail. Cheers
John.

John:
Earlier on I would have stuck to the "normal" opinion that rubber bushes provide better flex while the poly bushes have longer life. There have been improvements in poly that would make me want to experiment.

When I say should help, it is literally should. It is theory only and I haven't found any good data. The suggestion would also be dependent on the bushes used. As an example, Superpro are designed to allow the bush at the chassis mount to rotate freely. The rubber will allow some rotation prior to their max deflection. Once that is reached they will prevent further rotation which allows downward travel. Obviously there is a lot more going on in the suspension components than just downward rotation of the radius arms. Typically, when one wheel raises, compressing the spring and shock, the opposing wheel will either remain neutral or drop. That causes a twisting motion of the radius arms at the chassis mount which will also restrict motion (flex).

My desire at some point would be to replace the bushes on the chassis end of the radius arms with Superpro while keeping the axle bushes rubber. My thinking is that the rubber will still accommodate some twisting while the poly will allow rotation. The rubber will also help with that old NVH (noise, vibration, harshness) issue. Someday I will see. Currently I use rubber for the same old flex argument.