RR spring ?

[Drake Racing]

2012 Gen-x by stuckey, car currently has 200 LR and 225 RR per his setup sheet,
car is good when there is traction with base setup, but lacks sidebite and drive when
track starts to slick. Ive been told to try 250 or even 275 RR spring, but this goes against
everything I think I know....Any suggestions? (also car burns RR tires up, but LR lasts 3 or 4
times as long). I know some will want more info, so ...550 lf..300 rf...200 lr...225 rr
140# bite...53.5 left 53.5 rear. This is on D55s with IMCA spec engine.

Curt Drake
Late Model #55x

[MLR19]

Drop LR bite to 60 lbs with driver. Soften RF to 275.

[Matt49]

Way too much bite to expect the RR to hold you on entry. Poor entry = poor exit so fix that first.

[Drake Racing]

Thats what I was thinking, but Stuckey's set-up sheet says don't leave shop with less than 140# of bite.
I'm assuming that's for open motor with soft tires?

Curt Drake
Late Model #55x

[MasterSbilt_Racer]

Thats what I was thinking, but Stuckey's set-up sheet says don't leave shop with less than 140# of bite.
I'm assuming that's for open motor with soft tires?

Curt Drake
Late Model #55x

That's for old way of setting up the car. Drag race ideas.

[hunterracing]

What bout left side weight shouldn’t it be more 54 or so

[Basecircle]

Try a spring rubber in RR for the feature to see how it responds to a stiffer spring rate?

[15D]

2012 Gen-x by stuckey, car currently has 200 LR and 225 RR per his setup sheet,
car is good when there is traction with base setup, but lacks sidebite and drive when
track starts to slick. Ive been told to try 250 or even 275 RR spring, but this goes against
everything I think I know....Any suggestions? (also car burns RR tires up, but LR lasts 3 or 4
times as long). I know some will want more info, so ...550 lf..300 rf...200 lr...225 rr
140# bite...53.5 left 53.5 rear. This is on D55s with IMCA spec engine.

Curt Drake
Late Model #55x
we run IMCA as well and these are the exact problems we have been having. If the track has a little traction/moisture the driver can nearly flat-foot it around the track. As soon as the track dust's off we struggle with drive off and side-bite.

[Jking24]

The heavier rr spring will put more load on that tire assuming the car travels the same the added load equates to traction ie... Sidebite. It's sometimes hard to understand. Also typically changing just one spring on one corner will not gain all the desired effects of the change usually other changes are made to compensate for the things that more rr load (traction) will cause. And then theirs spring energy..... but were not their yet

[billetbirdcage]

*Note: I'm the worse Masterbuilt guy there is and very little experience with them but the times I messed with a few of them, they just confuse me and never reacted like other cars for some reason. SHRUGS

That being said, many of the gen-x guys around that time complained the cars where good on 20's or soft tires but as soon as you bolt on a 40 or hard tire they struggle.

[Jking24]

I also have messed with very few of them but the ones i have were smack down and early genx cars and they responded very well to rocking the car over staticly but nobody was checking deck heights back then

[a25rjr]

I also have messed with very few of them but the ones i have were smack down and early genx cars and they responded very well to rocking the car over staticly but nobody was checking deck heights back then

same here.......also they responded well to birdcage indexing and moving rr shock mounting location.

[latemodel22]

Since were talking about RR springs, what would be the difference in stopping that corner at say 18.0" vs 17.25"? same spring rate

[CCHIEF]

53.5 rear!! On hard tires. Work on that! Does the car have the same attitude when the track slicks off as it does when it's got grip. That is the ideal goal for success in the slick. Do you have a bump stop setup correctly on the RF? What amount of power does the engine make?? Steel block? How much are you off/on lap times from best cars. Heat and feature. ...or are you the fastest on a track with grip? You have to get ANY and ALL the push out of the car in and thru the center for success on a flat foot type track.Tight in will

[Drake Racing]

Steel block...limited HP..maybe 550, or even less when we run restrictors for different rules
car has bump stop in rf, and pogo in lr... attitude seems good, just isn't real good in the
slick. One more ? Track is 4/10 fairly high bank so I'm using the 16" right lower bar, should I be using the
14" bar in the shorter holes?

Curt Drake
Late Model #55x

[Matt49]

Shortening the right lower bar will typically tighten the car overall.

[a25rjr]

What spring do you have in the 5th coil? We always had to run a 350,in the slick, in the first hole, just like the supers!Also, we lowered the jbar into the lowest hole on pinion and indexed the lr top rod on the birdcage.

[CCHIEF]

Whats a "pogo" LR? Where are your lap times? This bump stop RF, dynamic load measured or just put a bump stop in it? I don't know MB car's droop range, but you may have too much droop in LR, the extra roll steer can really help you roll the center..or ruin you. "Burning up rr tires" either your too tight in and thru center and sliding the car to turn it ( what I'm suspecting ), or it is truly loose center out. Tough call without it all (accurate detailed info and video). HTH CC

[Drake Racing]

High compression/low rebound with a traction shock....all 4 shocks from Advanced valved for
that car 13" of droop which is what mb calls for.

Curt Drake
Late Model #55x

[CCHIEF]

So how do your laps compare. Track use transponders? If so what track? Some older cars don't have RF frame/crossmember ground clearance needed to run some of the later type setups. I don't know MB specifics. A 300 rf spring better have a properly setup bump stop . Lower HP cars like lighter LR springs, help to keep roll/hike in car when track slicks off. The knee jerk reaction is to tighten the car, because it is loose off, when usually too tight in/apex is the problem. Are other cars still flat footing in the slick?

[Drop Shock]

Put 5 gallons of gas in it, add about 1/2" of drop, and put a right rear tire on the left rear and go race