Mastersbilt Gen X HELP!

[hucktyson]

The new ones appear to have an xr1 type underslung. Many people did that before as the gen x cars are crazy flexible. Push down on your back bumper and watch the roll cage when it’s on jack stands

[hucktyson]

Am I assume the new ones are docol

[RaceEngineer]

are the newer cars gilpin and casebolt are running a completely different style? alot of MB down here but i never liked how much they flex out

Unless gilpin got a new car very recently, both of those cars are not the newest design. Or so I was told.

[genx5]

That's way too soft of a spring on that car to not have a bump stop. You are completely de-wedging the car and should not expect any forward drive with that setup.

So the car is probably rolling too much on the RF? I race in WV and OH. The krpytonite guys dominate here and their cars stay pinned on the RF.

[hucktyson]

No , you have to be over on the right front but you need a bump stop towards the end of the travel. I’d put a 250 or 275 on there with an 850 bump spring and shim it to about 2200 at the 4” masters intended it to travel and make sure you have enough zero point to hold it there

[RaceEngineer]

Mostly sound advice above, but a bumpstop requires less aggressive zero point and low speed rebound.

[hucktyson]

Raceengineer I don’t like how they keep packing further and further down until you start bottoming out when the track is fast and you can really stay in the RF. I always used rubber bump stops but after using bump springs I can’t see ever switching back

[RaceEngineer]

I don't have that issue. But I do things differently than most. If you want to stop the suspension at a repeatable place, a progressive rate is best. A progressive rate also bleeds off load fast so the shock doesn't have to be as stiff on rebound. Over damping kills traction.

[hucktyson]

I guess you are running something harder than a Penske blue then

[hucktyson]

The bump spring does get progressive as it starts to coil bind ..

[RaceEngineer]

The bump spring does get progressive as it starts to coil bind ..

I don't like binding springs. I believe linear for ride and progressive to stop. It's just my philosophy. I don't use the cone, tree, whatever you want to call it style bumps.

[Matt49]

On the Penske black, we definitely had issues with it packing down and eventually causing us bottoming issues at a high banked place. Going to the blue fixed that for the most part. We're likely going to get away from bump rubbers and do some more work on dual-stage springs (stacked). It seems like there is more margin for error there than the bump spring in terms of travel allowance before it starts getting progressive.

[SmithGT]

What's the best spring option on the RF of a GenX if you can't run bump stops or stacked springs?

[TheJet-09]

I've heard and believe a 350#, maybe 325# is a good starting spot. I was wondering though, with all the talk about the RF, is everybody on the same page as far as what lower shock mount they are using (there are two on a Gen-X RF lower)?

I learned that lesson when I first got mine, and there is a fairly significant difference in the motion ratio between the two.

[hucktyson]

The softest spring that prevents the car from slamming off the ground ... sometimes that might be a 375 other times it could be a 275 depends on the track and conditions. I believe driving style plays a roll also some styles generate more RF load than others

[RaceEngineer]

The softest spring that prevents the car from slamming off the ground ... sometimes that might be a 375 other times it could be a 275 depends on the track and conditions. I believe driving style plays a roll also some styles generate more RF load than others

Don't forget shocks. 100# @ 10 in/sec compression and you bottom out with a 650# RF spring.

[Matt49]

I've heard and believe a 350#, maybe 325# is a good starting spot. I was wondering though, with all the talk about the RF, is everybody on the same page as far as what lower shock mount they are using (there are two on a Gen-X RF lower)?

I learned that lesson when I first got mine, and there is a fairly significant difference in the motion ratio between the two.

Inside hole. Moving to the outside hole stiffens the RF significantly.

[RaceEngineer]

I always use the outside because it is similar to the smack location.

[hucktyson]

Have you done anything to stiffen your gen x ? I plan to start working on mine in a few weeks. I just have to decide if I’m going to buy a crate or not before I decide what to do to it ...

[RaceEngineer]

Stiffened the front. Not the rear. I think doing the rear isn't a bad idea.