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propit21
02-14-2012, 10:46 AM
helping a friend with his street stock. Car weights 3400lbs motor is in stock location and the way the car is right now its running lf 1050 Rf 1200 springs has hidden coil adjuster and stock mount front shocks, running pro 3 way adjustable shocks. Running a large 3/8 mile track that is tacky in the heats and some what slick during the main lots of momentum going into the corners. Does this seem to heavy or is it ok? Car is loose through the middle and exit.

Rear set up is stock 4 link with lr 225 13" and RR 200 11" with pro wb shocks lr 3/5 and rr 4. Been thinking of dropping the rr spring to 175lbs 13" and running either straight valve 3 or 4 valves across the back.

bite is around 200lbs
left 53 %
rear 52%

Front end parts are all stock except taller balljoints and 2.4 caster split.
Rear is all stock except for shocks and springs and coil spacers to adjust cross/bite

Should i drop spring rates in the front and RR or leave it alone, driver states loose in the middle when gettting on the gas and loose off exit. Tad tight going in but not bad.

dirt2
02-14-2012, 08:48 PM
Check your PM.

Thanks

rebel1mcelroy
02-15-2012, 07:06 AM
I would like to know also! I have the same prob and I'm running the same setup and weight.

Driver88
02-15-2012, 04:46 PM
http://www.4m.net/showthread.php?240778-metric-car-setup. There many threads on this subject.

turner
02-15-2012, 04:55 PM
Talk to stock car driver on here. You may not like what he has to say, but if you do what he tells you, your car will be capable of running in the front ( if you have a decent driver/engine) . He has helped me a lot and he will tell you like it is.Good luck.

rebel1mcelroy
02-15-2012, 07:02 PM
Thanks I'll give it a try!! I'll tell u how it goes !

stock car driver
02-15-2012, 07:13 PM
I give up..............

rebel1mcelroy
02-15-2012, 07:18 PM
I will do that ! Thanks

propit21
02-16-2012, 08:47 AM
stock car driver: not arguing with you setup just would like to know why it works maybe you can explain a few things. Why is it that all the chassis builder that build stockcars like harris, smiliys, jet, victory, and so on recommends s spring rate in the front somewhere like LF 1100 RF 1200? Just wonder why their base setup are so high in rate? Also on our prostock camaro clip car that weights 3000 lbs we don't run that low of spring rate in the front even and couldn't? Is thte roll center of a metric front end why you need to run softer springs? Also don't really know much about reverse spring setup to much maybe you can explain on why the left front needs to be heavier then the right front? Also why do you need to set the back higher then the front?

charlie11515
02-16-2012, 09:48 AM
i ran your set up on my modified last year about half way threw the season, i didnt tell my driver but he noticed right away and loved it, we went from a mid pac car to running up front every night. thanks for the info you put on here

3dinter
02-16-2012, 10:58 AM
We are about to start our season "Mid to Late March" here in Texas and i set my car up like he advised me and i wil post back and let you know, but from what he has told me in the past, i like his setups also. I also had the 1000 lb and higher springs in the front and went down to around 800 lf and 900 rf, im gonna try this first then switch them on practice day to to see what works the best for my car.

propit21
02-16-2012, 12:47 PM
sorry stock car racer for upsetting you and trying to learn nevermind i even asked questions.. As far a the word NEED your right i don't NEED to do anything someone tells me to do, you just seem very Knowledgeable about these type of cars and thats why I was just asking a few question. Thanks for the help.

propit21
02-16-2012, 01:33 PM
i do not know name of anyone who drives hobby stock or street stock type cars anywhere except my local track. I know from looking on those company web pages or catalogs that is the base set up printed or written. As for our pro stock we have tried a 925 rf spring and at the smaller tracks we race on it does work but we do get alot of shock travel. We have also ran reverse spring set up when we first got our pro stock but found that a heavier rf spring works better for us.

burnerdaddy
02-16-2012, 01:40 PM
I know for a fact if we tried to run a 900 rf spring the car would bottom out and about roll over... You must not run your roll center anywhere close to where i run mine. Thats why my car like 1200Lbs rf front. likes even more on big tracks with banking or i just move my roll center to take leverage out of the front end... seems like you soften your springs to get it too roll my car has tons of grip in the front and seems have better drive off with heavier springs. When I first started I ran 900s straight up in the front when i didnt know anything about front end geometry car still was tight.

burnerdaddy
02-16-2012, 02:04 PM
Because where is the roll center in a bone stock metric oem front end? 12 inches in the ground far right?? I can see it working on that front end but not one that can be modified.

burnerdaddy
02-16-2012, 02:47 PM
Yes I have plotted mine. Thats where my car started off as lol i dont know the exact numbers as its been a few years ago but it was way screwed. Im just stating that there is no way possible if i put a 900 the right front with the front end set the way it is now it would work. With the bite my front ends now i wouldnt even try it. Shocks play a key role in all of this too. I remember the first time I ever went to a big 1/2 mile went into one and thought the car was gonna roll over it was on the right side so hard. That was with a 900.

Dirtrunner35
02-16-2012, 08:49 PM
Put your scales together with 4 springs the same height with different lb springs on them, put the heavier lb spring on the left front scale, put a board on the 4 springs. Put a 100 lb in the middle of the board, which scale shows more weight????? I ran my clip stock car with the heavier spring in the left front, worked great.

gadirtracer
02-16-2012, 11:22 PM
Why will a softer spring cause the chassis to bottom out less than a stiffer spring?

billy5
02-16-2012, 11:58 PM
the softer spring already has more [stored energy] in at and resists more tranfer to it,yet yeilds greater transfer energy while accelerating the car in a forward direction thus provides more sprung weight transfer to the rear wheels....try it....if you dont like it then then change back..or dont try it and stay the same as you are now....i went from a 1000lf and 1200rf to a 900lf and 800rf..car turned way better but bottomed out rf at just about every entry on a high banked slick track using LOTS of brake...so for shizt and grinz i put a 11'' 1300 lf and a 12'' 900rf then i didnt have to use no where near as much brake on entry and the car seemed to [unload the left rear] and steer around the turns without abunch of sideways sliding and i could give it alot more throttle alot sooner coming out......on another note....why do people [ beat people up] after they ask for help and dont get answered what they want to hear?? if you dont agree..dont do it....if you know a better way and care to share your experience then great...i will probably read it ,and if it sounds logical,then i will probably try it....might work..might not...if you dont try it for yourself then you will never really know....i for 1 really appreciate being able to read all the different ideas...but i apply common sence to the situation im getting in

burnerdaddy
02-17-2012, 08:59 AM
Stock car so was my main problem when i tried the light springs set up is i didnt have enough spring split in the front to see the dif? Straight up 900 sucked!

propit21
02-17-2012, 10:21 AM
just to carry on the conversation, why do people run the rf heaiver setup?

stockcar5
02-17-2012, 11:14 AM
stock metric roll centers are below ground level but depending on what software you use when plotting it the numbers will not be accurate below ground level. the cheaper programs are not designed to calculate below the ground. all you need to know is if its below ground or not and fix it. and yes raising the roll center will allow for much softer springs.

propit21
02-17-2012, 12:16 PM
trying to learn...

LF heavy take away bite on entry so can run more bite in car correct?

heavy spring gets the weight, on entry most weight goes to LF which takes cross (bite) out of car and loosens entry, then wieght is transfer to RF spring which is softer and at that time allows more compression of weight onto the spring which in turn transfer more weight to the LR as you pick up the throttle, tighting the car correct?

RF heavy spring adds cross (bite) into the car on corner entry which keeps it tighter on entry.

softer LF spring help loosen car at entry known fact so yo can still run more cross (bite)

Heavy RF spring recieve more wight then LF which keeps Cross (bite) in car through out mid and exit. May not transfer wieght as well but keeps car tighter through mid and exit

just trying to learn so i know what am doing to the car not just putting a set up on the car.

keithbaker
02-17-2012, 01:25 PM
Late models always run a stiffer lf

stockcar5
02-17-2012, 02:18 PM
stiffening the lf spring tightens entry by reducing bite on entry. best thing about tuning with the lf spring is it has little effect on corner exit. there is also a slight aero advantage to pinning the rf on entry and letting the lr up in the air. of course its more prevelant on cars with decks and spoilers.

burnerdaddy
02-18-2012, 12:02 PM
Seems like lm and mods stopped picking up the lf years ago... Its hard to believe that running lighter springs in a metric front end in a stock than we do in a chevelle front stub on a modified works. Have to give it a try sometime this season i guess see what happens...

twizted
09-25-2012, 09:42 PM
Brought this back up top as it is similar to my car and hoping to get some more input on a 3400 metric pure stock setup. I am interested in the idea of the soft spring setup but cant find recomendations for spring rates front or rear from tha man? If you know the setup and not judge could you pm me the info please rates, length and shocks and any info possible. Thanks in advance

Ricky76
09-27-2012, 04:38 PM
I've seen on here that some people say run the rear lower control arms as close to the rear end housing as possible and some say run them as low as you can and with 10-15 degrees of angle ? I'm just wondering what the different ways will affect ? We're having a 2 night show next weekend and I was wanting some info on this before next week. I know it's trial and error, but I don't want to run bad in the heat and put me in the back for the feature without not knowing what this will effect !!! Thanks, Ricky

Dirt Knife
09-28-2012, 07:27 AM
http://www.printsextreme.com/Wilmot_Raceway_9.8.2_g271-Wilmot_Raceway_9.8.2012_Racing_p125254.html

Ran 750 LF 700 RF Car weight 1725 accross nose Ride height 7.5 to 8.5 ranges
No bottom out

Lower cont. arms the more up hill angle to the front the FASTER
the rear tires will hook up But not as long down the straight

The flatter the angle the longer it will stay hooked up yet not as fast

With the heavyer left front loosens going in (I ran less than 3/4" stagger)
AAnd 150 # Left rear bite

Dirt Knife
09-28-2012, 07:40 AM
Granted this is a B- Main

Yet the front 4 cars including me are all top 10 in points.

Just a live example The 53 car and the 13 car run the heavy front springs

http://www.youtube.com/watch?v=HvLawQqu2QQ

The softer springs along with the more left roll center Lets the
front susp work

I started 18 in the feature finnished 8th that night.