Class 7200 build with 8 a-arms and lots of cv's

[D.Mavis]

10.5 degrees top and bottom in the rear.

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[R&R FAB]

Ok it looks like more in the pics.How does rake in back effect handling?Im building a play buggy with aarms all around and have been thinking about how much rake it should have in back,it has 8* in front. thanks

[D.Mavis]

R&R-- thats the answer I'm looking for as well! I matched the front. the front I went with about 10.5 on the lower and more on the upper, that gave me a shorter side view swing arm length which should bring me to about zero anti dive in the front. I could have gone with more rake in the font but then I'd have to incline the upper front A arm even more which leads to castor gain in bump which I just guessed at as when it was too much. those two things work against each other. Then I just matched the rear with the front lower in side view. the rears are parallel in side view which gives about 30% anti squat. I dont know if thats a good number or not though.

[partybarge_pilot]

Ask Rob Mac about this, Mighty mouse has about the most rake of any desert racer ever built. The new Vildosola TT seems to have a fair amount also.

[R&R FAB]

Ive got a good idea about how it effects the front but I haven't seen much info on the rear.It seems that even more than 10* may be ok but I havent played with it so Im only guessing.It makes scene to have rake on back and it should almost act like trailing arms.?

[D.Mavis]

R&R--- it will be interesting to see how it affects the rear. theory is fine but you never know until its built and driving. I tried not to go too radical on any of the angles so that I'm reasonably sure it will be drivable. I tilted the rear arms so that like the front the wheel would move back as it moved up in a more natural path when it hit a bump. The byproduct is anti squat which seems like a good idea. Theoretically it seems like the more the better but that is definitely not what I hear from a practical side so I chose this geometry with looks like it will yield about 30% at ride height. There is a lot written about anti squat but not as it relates to off road. I'm sure googling the term would get you up to speed. There is a lot of contradicting ways of analyzing anti squat as well so I think its best to take it with a grain of salt and look more at the concept than trying to pinpoint a particular number. Also just finding your vehicles CG (especially before its built) is no easy task.

[R&R FAB]

It will be good to see how it turns out.So the more rake the more anti squat,so to find the prefect * it would take building it to find out.To bad a-arm mounts are not something thats easy to change around to play with the #'s.

[isdtbower]

If you look close, you will see that one of the front and one of the back A-arms are adjustable. They fully intend to play with the numbers. I,was very luckily, and got a first hand tour. They have incorporated a lot of "New Tech" with much of their own thinking and experience. Waiting on a Motor and the Mill has slowed their progress but probably not their thoughts. With that mill should come a big steel and aluminum rack, and progress! ! !

[D.Mavis]

quite a bit of progress. picked up the motor, 500hp which without a torque converter should move the race car pretty quick. we made the headers, plumbed the cooling system, rear engine cage etc...we are working on the uprights and hubs, the uprights are going to be billet aluminum. We are waiting on finalizing the design until we finalize our wheel choice. , here are some pics that are sort of recent

[mosebilt]

reminds me of my own car!...i like this thing..hopefully the rear arms upward kick doesnt cause alot of wheelspin/"hopping" through the rough stuff..Nye did this on a few cars (Nick Baldwins 4WD class 1, the bass boat i believe..maybe more-Phleugers new truck is the same too i think)...caused the rear to "hop" alot through the whoopps, plus excessive wheel spin since it moves away from the obstacle as you hit it..works great in the front (i run 10 degrees on all my cars in the front), but causes problems in the back, so i am told (they could never get the mentioned cars to ride well, minus phleugers)...i dont know, i run the a arms flat in the rear...bitchen truck!