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Author Topic:   Spring on top/swingarm
FASTLAP
Member
posted February 05, 2004 06:04 PM
from what i have seen and been told, the spring on top of housing helps create more bite as too spring being on swing arm.
We are going to try it on our car this year.


FASTLAP
Member
posted February 06, 2004 03:44 AM
we did the same last year with our swingarm car. at the end of the year we just locked the lrbirdcage and removed the rearward arm and it made a ton of difference. we are going to start this year with the same thing as the track we tried it at last year was more of a big sweeping type track where our normal track is a smaller 3/8 two dragstrips and two tight corners type. the only other change we are going to make is instead of a j-bar running from leftside over rearend to right side of housing, we want to put just a straight bar from left side of chassis to leftside of housing. Any suggestions on degree of angle, how many inches higher on the chassis than rearend etc. Any info would be appreciated. On a side note our car is a GRT and we cant change it to a 4bar on the left because on this one they moved the cage back 4inches so there wouldnt be enough room as its tight now between wheel and back of cage. we could move the rearend back a bit more but not sure if its still enough so well try what we have. this is the last year for this chassis anyway so well make due. thanks again if anyone has any ideas on the straight bar deal.


zeroracing
Member
posted February 06, 2004 07:28 AM
thanks for ideas guys. we run a 850 pullbar spring and havent had any bottoming out problems to speak of. were really hoping with a few small changes it will get us up there a bit closer. usually the car is good on tacky but really lacks on dryslick. we usually qualify 10-18th or so out of 40 cars weekly and 3-7 tenths off fast time. any small improvements will help our track position greatly and hopefully enough to move us up in th heats in order to transfer to feature more often.thanks again for the ideas.


maupin11
Member
posted February 09, 2004 07:56 PM
hmmmmmmmm, just curiousto of what spring rate you use with the top of the left rear axle? I drive lm's now, but i still like hearing about the changes in mods? thanks

[This message has been edited by maupin11 (edited February 09, 2004).]

Ego Racing
Member
posted February 09, 2004 08:02 PM
If the original was in front it would act softer as the chassis gained leverage on the spring. If it was behind it would act stiffer as the chassis lost leverage on the spring.
Also lowering the position of the spring helps the chassis get on the spring. Raising the top to put it on top of the axle would slow thw weight transfer to the spring.


Pa FastBoys
unregistered
posted February 11, 2004 04:47 PM           
On my Laser swing arm mod the base set up with both side spring on the forward bars with the LR being a 250 and the RR being a 275 with a 1000 pull bar spring. Now when claping the LR and taking the back bar off, running like a 3 link car, we would drop the LR spring to a 225 and the pull bar spring to a 700. Never tried a strait bar but I am going to this year. I run my J-bar at about 6 inches higher on the frame than pioion. Car is real drivable , no hicking, and the forwarb bite is awsome. But Im still open to a few ideas on my ride....anyone?...lol


Sidebite252
Member
posted February 16, 2004 06:09 PM
Here's something that will blow your mind. Pitted beside a guy last year that build his own cars and got to talking to him for help on my old Hoover chassis (short swing arms). Then he shows me whats under his car. I don't know details but he's running a short swing arm on the lr and a long swing arm on the rr (no z-lings) with the springs on top of the rear end and the shocks mounted on the swing arms. How did it work????? He won the freakin feature. I want to know more!!!!


zeroracing
Member
posted February 16, 2004 06:17 PM
if you have the springs mounted on the rearend, it will work like a 3 link with springs on top ofthe rearend.(since there are not any backward link parts, then it will just be a 3 link).
running a z link bar on the rr will get more bite.