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i know this is a late model board,, but you guys are far more advanced than me,, so I thought you would have more knowledge to help me..Metric a frame location helpwe are building a new chassis, imca stock car, we are allowed to fabricate the upper a frame mount and relocate it. We must use stock lowers, stock spindles and imca upper a frames. My question is, what types of things should I measure to get the optimum placement.
I think in order for sombody to help you their gonna need a little more info on the rest of the car. i could imagine the preferred front end settings will be very different if you running one of the high role over (latemodel style) setups with a link removed in the back vs a more traditional tru factory 4 link setup.
Factory 4 link, with multiple hole lower trailing arm mounts, the lowest hole on the left rear is about 7" down from housing, we can relocate shocks, move springs in front, rear or on top of housing
There are a bunch of IMCA centered tech pages on FB... and Id crawl around the top cars in your area and ask a lot of questions.
I do not want to just copy someone, I want to do it, and I want to know why to do it
then do what krooser suggested , read and gather all the info you can and use this to come up with your own ideas ...
Optimum front end will depend mostly on driving style and what you want the back end to do. Think total combination.
Fast Ford, what do you think im doing? Trying to gather information, and it appears no one wants to share information.
thats because what you are needing is easily obtainable on the net , im to slow at typing....lol....BTW , there use to be several street stock guys , one was stockcardriver i think , that was pretty knowledgeable but they never posted in this section , you might try posting in the street stock section and they might see it , just a thought......
If its a metric why stock metric lowers? Is that a rule that the lowers must match? If just stock lower is the rule then I'd run the nova lowers or if any stock lower can be used I'd run ford crown vic lower on rf and caprice/impala on the left front?
Lots of options. In general the front upper location is based on the length you intend to run and the upper control arm angle you need to run to get the geometry correct at a ride height that will be determined by the lower control arm angle desired to make whatever setup work. Start with a track width desired, then determine a roll center location, and target everything else to get you there. Frankly, I'd copy something that has been done already.
locating upper A arm mounts is very complicated. what comes to mind real quick , but are very important , Camber Gain , Castor gain/loss , Anti-dive/Pro-dive. If you google those subjects , that would be a start , and then how each apples to dirt oval is another hole subject to argue. Then there's roll center location , or roll center travel. All of this relates directly to the mounting of the "lower" control arms. Are you allowed to move the lowers? Can you shorten the left lower?
sorry jto , didnt realize you had posted in the dirt stock section , i hardly ever look there , my bad......
I've read the articles online, but that only consists of reading, I cant ask anyone questions by just readingand article, or get other opinions, I wanted to have a discussion, of things people have tried, achieved, didnt like, what to look for, etc etcYes, we have to use the stock metric lower a frames and stock spindle, we can move the lower some, not a lot, which I intend to do.
Give how you intend to used the rear suspension, as the front must compliment what you are trying to do there.
Do you intend to use a lot of travel at the right front? Keeping the font tires at the correct attitude to maximize available traction is an important consideration .Dynamic conditions are most important when considering static starting points.
Start with a basic stratagy for the entire car, then ask direct questions.
The original posts were very vague, so you got vague answers.
I'm not sure what the correct terminology is, but we are going to be using a tall soft lr spring, preloaded, short stiff right rear spring, attempt to keep the rf down as much as possible and the lr up as much as possible. As well as attempting to play with a short shaft left front shock
Is the plan to try to coil bind rf to maintain attitude?
My advice is to set your frame at the attitude you wish to run. Probably need engine in car with headers, radiator, etc.
As I stated in other thread, the rules and required tubular a arm limit where you can put the mounts.
Tack weld the upper mounts in place where you feel you have correct caster and adequate camber to get the best traction at the rf while in that attitude. Do the same for the lf.
Look closely at where this puts the dynamic roll centers.
Set it back at ride height and determine if bumpsteer will work.
Compromise from there.
There's a reason why builders like Rocketman in Phoenix City charge 30k for a complete car!
You're right, there's a reason chassis builders get away with charging so much, but we're not rich, were not spoiled kids, I prefer to build our own, and know why something works or doesn't work, i do not want people holding our hands and telling us what to do,
as for holding the rf down, itll be a soft spring, probably 600 or 700, with an extreme tie down rf shock
After thinking about it, since most are running the new aftermarket frame, why dont you try to buy just the frame from Rocketman, and finish it yourself. You'll be wayyyyy ahead of the game!