Mastersbilt Gen X HELP!

[Jim11h]

New chassis to old all parts swap over. Chassis difference is going to be bolt in 4 bar mounting plates, x brace in front of radiator, bar from top of of hoop ( where top stiffening bolt on bar attaches) back to drivers (not a nice word)(not a nice word)(not a nice word)(not a nice word)pit to stiffen front end. Right frame rail moved bends to give more clearance, moved bars around to give more j-bar angle on chassis. Bolt in underslung with more room. Can get up to 18" droop and have like 5" in rf. Also work done on rack mount for clearance. Driver (not a nice word)(not a nice word)(not a nice word)(not a nice word)pit enlarged and halo area bigger to contain driver better. Sounds like material will be regular steel or docol. Car in shop is docol. Seen car up close and spoke with them about it. Sharp looking for sure. Test car has way more 4 link adjustments than anyone needs but that's why this is r&d car

[garrett87]

Why don't they build those tail sections with an x like Ed Howe used so successfully with his dirt chassis? Seems it would take all that flex right out of the back end. Looking at those Pennsboro pix I posted in the "Wild West" section I'm reminded of the Whip Mulligan car Larry Moore drove in '83. Around 1600 lbs. maybe less. That car would flex out in 20 laps then come back for the next race/practice and run good for another 20 laps until it was junk again. I don't believe Moore ran that car in the World that year... he brought two cars as I recall.

Yes but that was one of those ultralite cars they built back in the day from what I have been told. That is possible. I was told Ronnie Johnson had an old 2x3 masters that he won a ton races in? Don O Neil was dominant in a masters too. We had one and it was a consistent car I will say that.

[TheJet-09]

Hay @Jim11h, are those numbers you put down accurate? 18" of droop?

I was wondering what kind of LR bar angles you'd have to start with to accommodate that much travel? Or what about the shocks (length or travel)? Just curious if that is even feasible...or needed.

[Krooser]

Yes but that was one of those ultralite cars they built back in the day from what I have been told. That is possible. I was told Ronnie Johnson had an old 2x3 masters that he won a ton races in? Don O Neil was dominant in a masters too. We had one and it was a consistent car I will say that.

IIRC that Mulligan car was built with one or 1 /4" tubing... looked like a sprint car with a body.

[hucktyson]

The original cars were set somewhere around 13” of drop , there are not shocks available that would
Be legal to get to 18” Unless the drop is being measured differntly maybe at the outside edge of the Lr wheel with the right rear compressed or something like that

[collateralDamage]

The Mastersbilt "R" series cars have a completely different rear clip than previous cars. 18" of measured droop might be excessive to some but the car is certainly capable of it.

[RaceEngineer]

The Mastersbilt "R" series cars have a completely different rear clip than previous cars. 18" of measured droop might be excessive to some but the car is certainly capable of it.

So the magic is partially in the measurement point? As Huck said, if you are very close to the shock, 8" of ride height, + 10" shock extension, would be impossible unless the front shock wasnt there or the stroke was 10".

[RaceEngineer]

I was happy getting a Gen X to 15" Huck. Lol.

[hucktyson]

The problem is actually the front shock indexing away from the mount as it hikes. You would probably need about 12 or 13” of travel to get a legit 10” of drop as it used to be measured. I imagine you could build a Lr shock that could do the job of both but it would have to be absurdly stiff. The other option would be to run the 9” traction shock on top of the tube and build a big box above the deck to cover the shock as that won’t fit between The tube and deck with how sloped the decks are now. Stiffening those chassis was the number 1 improvement needed.

[RaceEngineer]

Depends on how much dynamic birdcage rotation you have.

[hucktyson]

Unless your top and bottom links are the same length and same
Angle it’s going to be more than zero. With the amount of top rod angle people usually use it’s significantly more than zero

[collateralDamage]

I should clarify. The frame rail of the R Mastersbilts are roughly 3" higher than the previous car. So you would add that to the ride height or droop number. Total travel capability is unchanged and still limited by birdcage indexing as long as the under-rail is deep enough...

[Kromulous]

I noticed some shock companies are offering a 10” stroke now.

So 18” I assume measuring from tube to tube, what’s ride height? Around 10” or so?

Interesting, I can get 6” of droop travel, probably 7” if I tried and thought I was doing something lol.

[RaceEngineer]

10" isn't legal by some sanctions.

[hucktyson]

Penske only has a 10” for behind. For some reason they aren’t making a 10” for the front . It’s the front that’s really the limiting factor. I guess you could have that 10” double adjustable valved with compression only but that’s an expensive “ traction” shock