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bjcrawfo
04-13-2013, 07:06 PM
Track is a very high banked 4/10mile dirt track. Its a bomber class.

LF 800 RF1250

LR 225 RR 200

Car handles good through the longer turns on the track which is 3 and 4, but in 1 and 2 the car is very tight and pushes up the track very bad. Running street tires BFG.

air pressures

LF 15 RF 18

LR 15 RR 16

I have been told to take 1/2 to 3/4 shims out of RR. Not sure. Any help would be appreciated.

mudeater18
04-13-2013, 08:49 PM
Make sure the RF spring is not bottoming out causing your push. 1250lbs sounds heavy but not necessarily for a metric front. A friend of mine use to run 1400 in the RF and 1200 in the LF of his bomber and he won about 40 features in 3 years with it. It was a 3000 lb weight rule class.

Dirt Knife
04-13-2013, 10:52 PM
950 LF 900RF

You are way to heavy RF its just like you put a solid bar there

Your nose Weight should be your spring weight /2

Make shure your shocks are not hitting or binding up.

what front end settings do you have

3250 total weight car with 1700 min nose weight I ran 900 and 850

Let it plant in the corners

JMO

Dirt Knife
04-13-2013, 10:56 PM
Bump the Rf up to 20 or 22 and the RR to 18

The side walls dont give you any benifit

Dont take the shims out of the RR
Dont trust the guy who told you that.

mudeater18
04-15-2013, 06:07 PM
950 LF 900RF

You are way to heavy RF its just like you put a solid bar there

Your nose Weight should be your spring weight /2

Make shure your shocks are not hitting or binding up.

what front end settings do you have

3250 total weight car with 1700 min nose weight I ran 900 and 850

Let it plant in the corners

JMONot trying to start anything, but that's just not correct info. Chevelle lowers have a 36% ratio. Metric lowers have a 23% ratio. If you have a 650 spring in a Chevelle you have 234# at the balljoint (650 x 36%= 234). So to get close to that with Metric lowers you'd have to run a 1000# spring (1000 x 23%= 230) to get 230# at the balljoint.. Modifieds with metric lowers run 1000-1200# front springs and they weigh 2400# and have 56 - 58% rear weight which has the fr wheel weights in the 500# range. Soft front spring setups are for 4 bar cars in which the birdcage can index and add LR when hiked up. Higher banked tracks also require stiffer front springs, because the car is pushed toward the track during cornering as opposed to rolling toward the RF. I'd make sure the RF isn't bottoming. Take the RF spring out. Jack up the RF wheel and see what will hit first (lower A arm to frame, shock travel, etc). Put a piece of duct tape where it will hit. Hotlap it and look at the tape. If it bottomed you'll see it on the tape. If yes, add more spring untill it doesn't bottom. I bet a 1400 or 1500# RF will fix it !

Dirt Knife
04-15-2013, 07:55 PM
http://www.youtube.com/watch?v=HvLawQqu2QQ

#50 car starting in 5th position it has the #31 on the hood for a sponsor

post says 950 lf 900 rf not 650 like in my mod

notice after the 2 yahoos in front finaly break clean with 3 laps to go to where I go around them
The 2 yahoos are 5th and 6th in points

3 laps to go by by notice how the r f stays pinned down not like a pogo stick

your nose weight shold be your front spring /2 aprox.

Dirt Knife
04-15-2013, 08:12 PM
shock travel indicators if your right rear has 4" compression
your R front should have the same. what ever the ### 3" comp. 2" comp ect.
ballance the chassis

if your Right rear has 4" comp. and your Right Front only 1/4"
or 2-1/4" with all the whole weight of the car on it ???? 3100#s

unless yor running 36* banking

just a thought

mudeater18
04-15-2013, 08:18 PM
post says 950 lf 900 rf not 650 like in my mod

Sorry I lost you. The 650 was an example to explain the ratios. I'm not arguing with you. Maybe the original poster will get what he needs from my answer. Have a nice day.

mudeater18
04-15-2013, 08:21 PM
unless yor running 36* banking

Poster said "Track is a very high banked 4/10mile dirt track". I watched your video, track is as flat as a parking lot. Look at any set up sheet for changes when going to a banked track. It will say "INCREASE front spring rates".

Dirt Knife
04-15-2013, 09:47 PM
You are correct.

He needs to look at his shock travel he pushes like a freight train in 1 and 2

When I took the my car same set up on a rain out date to another local track
30* 1/2 mile
it carried the left front
all thru the corner and passed 4 cars per turn had to sart in the back (visiting driver penalty)
they stoped the feature and kicked me off the track for good. no imca, or ump, wissota here

the corner with the stiffer spring will get the most weight and overloads the tire
if his caster and camber and toe are set right drop the spring rate
350+ lbs
do what your car needs ifit starts to push in 3-4 from bottoming out then bump up 50 lbs

my car ran 1" off of bottoming out I would guess he is 4" from that

mudeater18
04-16-2013, 06:10 PM
Adding more rf spring will make the rf bottom out more not less. .

Whaaat ? Happy racing to you guys. lol !

bjcrawfo
04-16-2013, 06:52 PM
First of all, thanks for all the input! I called medieval chassis today and told them my problem and what I had to work with and basically they told me that the problem was that I had to much split in the front springs. They said that I needed to keep the 1250 in the right front, but to ditch the 800 LF and put a 1100 in the LF. That was there .02. So I'm gonna try some things and see.

turner
04-16-2013, 06:57 PM
Make sure that if you are using a stock mount rf shock, that you space it down from the lower a frame atleast 3/8 " from my exp. I run stock car drivers setup, and it is the best thing ive ever done. Good luck.

bjcrawfo
04-16-2013, 07:08 PM
Make sure that if you are using a stock mount rf shock, that you space it down from the lower a frame atleast 3/8 " from my exp. I run stock car drivers setup, and it is the best thing ive ever done. Good luck.

We do have to run shocks in stock location. What are you referring to space it down 3/8"?

turner
04-16-2013, 07:41 PM
We do have to run shocks in stock location. What are you referring to space it down 3/8"?
When we ran the shock mounted to the lower A frame it would bottom out . You may need to put some washers between the lower a frame and the shock.( lower shock mount will be lower than a frame) We put 3/8 spacers in there and haven't bottomed it out since. Doesn't take alot , but it made a world of diff in the handling, because we were bottoming the shock out.

mudeater18
04-17-2013, 06:15 PM
First of all, thanks for all the input! I called medieval chassis today and told them my problem and what I had to work with and basically they told me that the problem was that I had to much split in the front springs. They said that I needed to keep the 1250 in the right front, but to ditch the 800 LF and put a 1100 in the LF. That was there .02. So I'm gonna try some things and see.I'd say that's definitely a step in the right direction ! Let us know the results.

Dirt Knife
04-17-2013, 08:15 PM
run sc driver and I's set up
still way to heavy

have you had the cars on the scales

just my .02

Dirt Knife
04-17-2013, 08:25 PM
take the top bushing off the stock mount shock Right Front
and run 2" bolts in the bottom mount with at least 3/8" spacers.
while you have the spring out runn the suspension full motion with shock bolted in
to make shure no binding.

on the left front take the bottom bushing off the top mount of the shock
and bolt right to the bottom of a arm

again runn thru full range up and down of motion with shock installed
no binds or rubs
install our spring rates and run up front

when you are done wasting time and money on springs
ect

remember this post

ss74
04-24-2013, 01:23 PM
1250 RF is WAY too stiff. I run a 850 on the RF of my 3200 lb metric street stock, whether I'm on a 1/4 or 1/2 mile track. No bottom out issues. I had 19 feature wins last year and am 3 for 3 so far this year. Listen to stock car driver. If you spring the front end like a tank then it's going to push like one as well. The fron and rear need to work together.

NDHobbyRacer
05-14-2013, 10:28 PM
take the top bushing off the stock mount shock Right Frontand run 2" bolts in the bottom mount with at least 3/8" spacers.while you have the spring out runn the suspension full motion with shock bolted in to make shure no binding.on the left front take the bottom bushing off the top mount of the shockand bolt right to the bottom of a armagain runn thru full range up and down of motion with shock installed no binds or rubsinstall our spring rates and run up front when you are done wasting time and money on springs ectremember this postJust wondering if it should be move the bottom bushing from the right top and move top bushing from the top left mounts of the shocks? Seems to me that you would want the right front to have more travel for compression and the left front to have more travel for the extension. Not trying to cause any arguments, just want to understand because we are gonna try this on our hobby stock. What springs do you recommend also? We are running a 1100RF and 1000LF.

racer67x
05-15-2013, 01:19 AM
Just wondering if it should be move the bottom bushing from the right top and move top bushing from the top left mounts of the shocks? Seems to me that you would want the right front to have more travel for compression and the left front to have more travel for the extension. Not trying to cause any arguments, just want to understand because we are gonna try this on our hobby stock. What springs do you recommend also? We are running a 1100RF and 1000LF.

go with a 1200 rf 1000 lf to start and increase the lr to a 275..if the car is still loose off add a couple shims/spacers lr till you hit the limit,then go to a 1300 and back the lr to a 250 and start working up again till you get it where you want.
want to to turn better go the other way..don't worry about the split just keep pushing the weight back..and remember opinions are like butholes,lol,keep playing with it and pretty soon they will all be in your way.
and put longer bolts with a spacer (old lugnuts) under the front shocks,cut the bottom hole a little for clearance.

mudeater18
05-22-2013, 06:21 PM
Any updates ????

bjcrawfo
06-29-2013, 05:36 PM
I have some updates. I finally got the car on the scales and it had negative cross in the car. Added cross to the car and won the feature race which was a bounty race. A plus plus! Since the win I have won one heat and have been broke previous two times to the track. Next race is next week. July 6th