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jack06
07-13-2014, 10:47 AM
Any info on 450 rr on mastersbilt smackdown?

hucktyson
07-13-2014, 11:02 AM
Did they move it to the back side
Of the axel ?? That causes the indexing
TO rotate away from the spring ... But a 450 is still really
Stiff even behind

TheJet-09
07-13-2014, 01:04 PM
You'd have to confirm the type of RR suspension being used (such as a swing arm). On a conventional 4-bar, I don't see how you'd ever use a rear spring that stiff. My 2008 does have a RR shock mount that is behind the axle. I believe some guys used to run a "wishbone" looking arm on the RR that connected to the chassis using only one point, which would've had the spring behind the axle, but that was a long time ago (late 90's?).

Matt49
07-13-2014, 01:14 PM
Jet, you're talking about the old "spear rod" for the RR and yes you had to run the spring behind but still 450 is WAY too stiff in my opinion.

Jack06,
What RR suspension is this? 4-bar, z-link, swing arm?

hpmaster
07-13-2014, 01:43 PM
Years ago I was experimenting with engine, ballast, battery and fuel cell heights on a 4-bar car. With all the components extremely high the stiffest spring we ever used was a 375 and that was too stiff. Can't really see how a 450 would work and if you did get it to "work" I bet your RR tire would give up very fast. JMHO

jack06
07-13-2014, 07:20 PM
4 bar. I've been hearing it was being run. Just trying to get some information about it.

drtrkr244
07-13-2014, 07:54 PM
Maybe its a setup when using lm40/55 on RR. It definitely would help it to build some heat in it, real fast.

Matt49
07-13-2014, 07:58 PM
4 bar. I've been hearing it was being run. Just trying to get some information about it.

I'd have to see it to believe it.
Are you sure that the people you're "hearing" talk about 450 RR aren't in swing arm cars. 450 on a 4-bar is WAY too stiff for any conditions. You'd never get any action in the car and it would just shear the RR tire contact patch. I think a car with this setup would find the fence faster than anything.

grt74
07-13-2014, 08:34 PM
Any info on 450 rr on mastersbilt smackdown?

thats sounds heavy but rr bar angles can and will change indexing, and if its slick enough???i wouldnt say its out of the question with the right setup,you would also want to build a shock for a set up like that,a standard spring is 200-275maybe300,so as you can see the shock will need more control to make it work

7uptruckracer
07-14-2014, 08:17 AM
My only thought would be its to keep the LF into the racetrack, and would help keep the LR from coming down too. (Sounds odd, but we do this on asphalt all the time and load up on wedge) I don't think it would work here but thats my only stab at what it could be for, unless its swingarm then

Matt49
07-14-2014, 03:19 PM
The only way I could see this working is if you had the lower shock mount moved significantly further out on the birdcage than normal and/or decreases the shock drop quite a bit from normal. Otherwise, I just think the wheel rate is way too high for the RR to work effectively regardless of shock valving. You'd either be bad tight from overloading the RR or bad loose from overloading it to the point of shearing the contact patch. I could be wrong but I don't think it would be driveable even with compensation made elsewhere.

jack06
07-14-2014, 05:15 PM
What works best on the right rear? What about stack right front?

grt74
07-14-2014, 06:59 PM
What works best on the right rear? What about stack right front?

what are your complants,and what are you trying to accomplish(what are you trying to fix)youll need to post your complete setup,pm if you dont want everyone knowing

grt74
07-14-2014, 07:02 PM
The only way I could see this working is if you had the lower shock mount moved significantly further out on the birdcage than normal and/or decreases the shock drop quite a bit from normal. Otherwise, I just think the wheel rate is way too high for the RR to work effectively regardless of shock valving. You'd either be bad tight from overloading the RR or bad loose from overloading it to the point of shearing the contact patch. I could be wrong but I don't think it would be driveable even with compensation made elsewhere.

it would run fine if you had very little to no indexing,just saying its not out of the question but it will take the whole setup and bar angles correct,ive seen 800-1000lbs on a swing arm setup,just saying with the right setup and track conditions it could be possible

jack06
07-14-2014, 08:09 PM
Lf 450 Rf 400 over 700 Lr225 Rr225 5th350 80 pounds of bit. J bar 8 1/2 frame 4 up 0n pinion. Car won't turn in on the throttle.

grt74
07-14-2014, 08:18 PM
Lf 450 Rf 400 over 700 Lr225 Rr225 5th350 80 pounds of bit. J bar 8 1/2 frame 4 up 0n pinion. Car won't turn in on the throttle.

400 over a 700 is an awful soft spring rate at 1st (254)i my self would work there first,or go up on the rr but thats a double edge sword,if your off the gas its going to be tighter getting in,but sitting here thinking,what about the lr bottom bar??? if it has the small adjustments go up a hole,that will free up the whole corner on the gas
,your scale #s can help some of that also
there a couple ways to skin that cat,1st bottom lr bar,if its to much put it back and work on the rf spring,i really wouldnt touch the rr,but thats me,just remember if you do go up on the rr and your not on the gas it will be tighter going in

grt74
07-14-2014, 08:32 PM
if you think it has too much drive,you can back of the rf lock nut(im guessing your using the dual stage setup)

jack06
07-14-2014, 08:32 PM
I think the right front is the problem. I ran better with a 10in 350 on it.

MasterSbilt_Racer
07-14-2014, 08:41 PM
I think the right front is the problem. I ran better with a 10in 350 on it.

It is hard to go softer than that without the correct package around it.

jack06
07-14-2014, 09:31 PM
What a good set up for steelhead motor weighing 2450 on a 4 10th miles track that gets a little dry?

grt74
07-14-2014, 10:11 PM
most smackdowns that i heard of really liked rf spring,with a steelheaded engine,i guessing here 425-400,masters may have a better answer than me on that,that will help in off the gas but will be tighter off than the 350,i know you have said that your going in on the gas but if its not a d shaped track or big sweeping corners ill bet your lifting,at least a little,good luck,but your on the right track,fix entry 1st then middle and exit
hope i helped some

jack06
07-15-2014, 06:33 PM
Stack or bump stop? Or just a standard 10 or 12 in sring? On right front.

fox1162002
07-15-2014, 09:12 PM
I heard a team using a pin down shock like 2\11 with 325lb RR spring. He is driving in super deep and the spring rate launches him off the turn. Idk that's the way I heard him tell it. But I'm sure its a whole package deal. I also believe its a long horn car.