12 Car front susp??

[doug969]

I have a 2 seat 12 car with 2.0 Fox 2 tube bypass and a 2.0 coil on the front and wanted to see if anyone has set up a car like this. After testing it feels a little harsh like I need to change the comp valving. Bothshocks still have the fact valving in them and Im thinking of taking some out of the coilover so I can ues the bypass shock for adjustments. what do you think???

[swiftracing5]

I have a postion sensitive and coil in front. But as a matter of fact, i was in barstow last night and was dialing in my bypass and c/o in the rear on my class 5. I have swayaway, but the rear was the right spring rate but it was bottoming out. So I tightened the allen on the compression tube and then it left and inch on the shaft unused, and it felt awesome.

[westtexasbaja]

I have a 2 seat 12 car with 2.0 Fox 2 tube bypass and a 2.0 coil on the front and wanted to see if anyone has set up a car like this. After testing it feels a little harsh like I need to change the comp valving. Bothshocks still have the fact valving in them and Im thinking of taking some out of the coilover so I can ues the bypass shock for adjustments. what do you think???

That would be the most adjustable if it won't overwork the BP...

Don't know if this will help but this is where I am: I have the exact same setup on the front of my single seat 12. Factory valving my CO is 40/60 and 90/50 on the BP. With both resi's @ 200 psi the ride is too hard (no droop at all) even with BP comp screws out all the way. I tested with 50 psi in both resi's and it was better but still stiff. Running without the BP with CO @ 200 psi it had droop but felt just a little too soft then.

Thought about taking some valving out of the CO but according to a Fox spec sheet the lowest comp valv is 30. So I'm going to leave the 40 so the BP won't get overworked.

I have all 2.0 on the rear with same valving as front, but it's too soft. So my plan was to switch the front BP 90 comp and the rear CO 40 comp. Resulting in a CO with 40/60 and BP with 40/50 on the front.

Another Q: Is there a way to compare pairs of valving working together to a single? Like 2 shocks with 40 each to 1 shock with 80?

[Fourstroker]

That would be the most adjustable if it won't overwork the BP...

Don't know if this will help but this is where I am: I have the exact same setup on the front of my single seat 12. Factory valving my CO is 40/60 and 90/50 on the BP. With both resi's @ 200 psi the ride is too hard (no droop at all) even with BP comp screws out all the way. I tested with 50 psi in both resi's and it was better but still stiff. Running without the BP with CO @ 200 psi it had droop but felt just a little too soft then.

Thought about taking some valving out of the CO but according to a Fox spec sheet the lowest comp valv is 30. So I'm going to leave the 40 so the BP won't get overworked.

I have all 2.0 on the rear with same valving as front, but it's too soft. So my plan was to switch the front BP 90 comp and the rear CO 40 comp. Resulting in a CO with 40/60 and BP with 40/50 on the front.

Another Q: Is there a way to compare pairs of valving working together to a single? Like 2 shocks with 40 each to 1 shock with 80?

Westtexasbaja - Sounds like you have too much spring. That would explain the "No Droop". I would try a softer spring and keep the compression where it is first.

[Fourstroker]

Doug,

Is your bypass 3-Tube or 2-Tube? Does it feel too stiff at slower speeds, faster speeds or both?

If 2-Tube and overall stiffness then lighter valving
If 2-Tube and Stiff at high speed open the bypass tube a little
If 2-Tube and Stiff at Low Speed then lighter valving and adjust bypass tube a little tighter
If 3-Tube adjust upper or lower tube depending on where it is stiff.

Hope that helps

[doug969]

The BP is a 2 tube and is real hard at slow speeds and is a little stiff or just right at high speeds. I niticed that I use all the shock shaft and both tubes are backed all the way out. ?????????

[westtexasbaja]

Westtexasbaja - Sounds like you have too much spring. That would explain the "No Droop". I would try a softer spring and keep the compression where it is first.

200 over 300 with zero pre-load too much? Car feels good and there is a little droop without the BP....

[Fourstroker]

The BP is a 2 tube and is real hard at slow speeds and is a little stiff or just right at high speeds. I niticed that I use all the shock shaft and both tubes are backed all the way out. ?????????

Then yes the valving is too stiff. I would lighten the valving and then mess with the bypass to your liking at the high speed. Unless the bypass tube was welded in a custom location that should help. On a 2-Tube shock they are usually welded to help you dial in the high speed compression.

[doug969]

am I right in changing the coil valving and keep the BP where it is??

[Fourstroker]

200 over 300 with zero pre-load too much? Car feels good and there is a little droop without the BP....

How much static suspension droop do you have? 20-40% of your total travel? For example if you have 10" of front travel you should have 2-4" of static droop with full nitrogen pressure. If you have less than that or zero droop then your springs are too stiff. Especially if you have no preload on them.

Are you running 2.5" longer arms or 4" longer arms? 250 over 300 seems to be the formula with 4" over arms for most applications. If you were to change anything I would change the top spring. Maybe 200 over 300 especially if the handling of the car is good at high speeds where the top spring will have already given way.

[Fourstroker]

am I right in changing the coil valving and keep the BP where it is?? Either way will work. Just make sure you keep the minimum required valving in both. I am not sure what Fox recommends. For our new car we are planning on running minimum valving in the C/O and the rest in the B/P. Takes one variable out of the equation. I just don't want to help you too much. That car is fast as hell as it is.

[doug969]

lol, I changed the coil from the last race because it was way stiff like driving a 9 car again. With the new coils it feels much better but still stiff, not the plush feeling that im looking for. It pops like a 16 right now and i want to get rid of most of that and let the susp do the work. The shocks would be cool after about 10 miles and that's telling me that their not working that much, both good and bad I guess.

[Fourstroker]

Sounds like you are on the right path. Will the car be ready for Dec 1st? If so be nice as you go by....I mean if you go by. Good luck with the car from what I hear you stole it.

[westtexasbaja]

lol, I changed the coil from the last race because it was way stiff like driving a 9 car again. With the new coils it feels much better but still stiff, not the plush feeling that im looking for. It pops like a 16 right now and i want to get rid of most of that and let the susp do the work. The shocks would be cool after about 10 miles and that's telling me that their not working that much, both good and bad I guess.

What rates did you end up with?

[doug969]

Who spreading bad rumors????? It should be ready, fixed some problems with the CV's yesterday and now shock time!!! Took it out this past Sat and ran it around Barstool for a bit with the new coils and to get some more seat time since Im new to the cars with wheel travel. I have about 1,000 miles now under my belt and still learning that damn trans. I have to stop and put in gear when I miss a shift, lol Thats the funny thing about the car is feeling like your 12 years old again learning how to drive a stick.

[doug969]

I think the first one was 250/300 and now 250/250


What rates did you end up with?

[westtexasbaja]

How much static suspension droop do you have? 20-40% of your total travel? For example if you have 10" of front travel you should have 2-4" of static droop with full nitrogen pressure. If you have less than that or zero droop then your springs are too stiff. Especially if you have no preload on them.

Are you running 2.5" longer arms or 4" longer arms? 250 over 300 seems to be the formula with 4" over arms for most applications. If you were to change anything I would change the top spring. Maybe 200 over 300 especially if the handling of the car is good at high speeds where the top spring will have already given way.

Not sure how much droop there was without the BP. Maybe 2". I'd have to pull the BP and measure.

4" arms. 200/300 is what I have now. Maybe try 150/300?

[Fourstroker]

Not sure how much droop there was without the BP. Maybe 2". I'd have to pull the BP and measure.

4" arms. 200/300 is what I have now. Maybe try 150/300?

Put 200 lbs pressure in all shocks and do the following. Jack the car up so that the tire are just touching the ground. Measure your ground clearance to the beam. Let the jack down and cycle your suspension a little until it settles into its natural position. Measure your ground clearance again. The difference is your droop and nitrogen pressure should have very little influence on that number.