Newb ? extreme handaling cornering.

Discussion in 'Race car chassis tech' started by Stubbe, Aug 15, 2007.

  1. Stubbe

    Stubbe Stubbe

    1965 Special, 73 455, th400, stock 8.2 posi or whatever. And almost forgot, its a 4 door. So doesn't have to look original at all. If I change the looks its how I like it, never gonna sell the car so who cares.

    So my car is now faster than all stock rice, excluding S200s and 3000s. Only problem is then they pull the, well you can't handel worth s333. Pretty true. What would be the best way to get great handeling out of my car. I was thinking as a big project in like 2 years of, and please no 100,000 options as I am 19, also known as POOR

    -setting the motor back
    -wide tires all around
    -new coils shocks, what ones? can I just go really stiff-ride quality isn't really a problem
    -Swaybars
    -What frame mods do I do, add braces anywhere, I have seen drag cars with tubing from the front frame to firewall, does thie help at all,
    -maybe 2 braces over the engine to tie it all together up there.
    -Does adding braces in the trunk or body for that matter of fact help.
    -And does anyone know how much weight is shifted when moving a 455 th400 alum intake back. Like 50lbs per inch back or something like that.
    -Also I heard mid 90s jeep steering boxes work good.
    -battery relocate to trunk.

    Would like the cheapest best parts I can get. If the best part is expensive I will buy it and bite the bullet, I don't want to build my way up and keep replacing parts. I'll just change it over correctly, but slower as income arrives.
    Thanks in advace, John
     
  2. bob k. mando

    bob k. mando Guest

    first, start googling "G Machine". and keep an eye out for articles on this in the major rod magazines. i'm pretty sure Hot Rod had one in the last year about an air suspension conversion that performed very well.



    stock 8.2 posi or whatever.

    this will affect maximum engine torque capability but as far as handling goes is pretty meaningless. your cars roll center couldn't care less how small the ring gear is.




    -setting the motor back

    well "Cheaaaa". are your engine mounts currently in the front pair of holes or the rear? if they're in the rear, swap them to the front. this will push the block back towards the firewall.

    you will now have issues with:
    a. drive shaft too long
    b. trans cross member
    c. trans linkages into the driver compartment




    -wide tires all around

    check. wider rubber and wider tires is always a good thing. lower profile ( <65 series) rubber will also have less sidewall flex, keeping the contact patch more securely on the ground.

    get 8" wide rims at a minimum preferably the maximum width rim that the tire guys recommend for whatever tire size you decide to go with. wider rims help to correct the shape of the contact patch as the tire is deformed by side loading. this is related to but seperate from the front suspension stuff i'll get to later.




    -new coils shocks, what ones? can I just go really stiff-ride quality isn't really a problem

    are you going to be autocrossing or just chasing rice burners on the street? maximum desired ride stiffness is a compromise between road roughness, minimum turn radius, car mass, etc. you make the suspension too stiff and the tires won't maintain contact with the road over rough patches.

    a car designed for Elkhart Lake is going to be WAY stiffer than would even be safe for a street car.



    -Swaybars

    definitely get a large rear bar. most of this early GM iron was designed to understeer from the factory. a big rear bar will both reduce body roll and and take out some of the push. a bigger front bar won't hurt ( it will also reduce body roll ) but it will tend to aggravate the push. make a bigger upgrade in the rear than you do in the front.

    along with this, you'll need to totally reset your front geometry. any car designed to turn has 1/16"-1/8" of toe out ( more toe out for tighter radius turns ). this is due to the physics of the turn. the outside front tire will draw a larger radius arc through any turn than the inside tire. this means that the inside tire must be turned/deflected more than the outside tire or it will fight the outside tire. any front end geometry set to straight ahead or the more normal factory toe in will scrub the inside tire and fight the outside tire.

    you will probably need to add caster to make the car track straighter.

    you will probably want a little camber but you won't be able to put in near as much as the circle track guys or bias it like they do.

    remember, suspension geometry changes are 'free'. buy or borrow the tools to measure these and it's a matter of how much you want to wrench on the car. any circle track guy or road racer worth his salt will have caster/camber/toe gauges.

    check the rear tires for zero toe. toe in/out on the rear indicates a bent axle housing.



    -What frame mods do I do, add braces anywhere, I have seen drag cars with tubing from the front frame to firewall, does thie help at all,
    -maybe 2 braces over the engine to tie it all together up there.
    -Does adding braces in the trunk or body for that matter of fact help.

    frame stiffness is always more gooder. the front and rear frame horns don't really do anything but hold up sheet metal though. frame bracing from the front X-member to the rear axle is worthwhile.

    box your frame and control arms ( weld em yourself ) where ever possible or upgrade to tubular control arm assemblies. you said ride quality was not a consideration so now would be a good time to mention neoprene or solid bushings.

    even if you don't get stiffer bushings you probably ought to put new bushings throughout the car. like it or not, 40 year old rubber just isn't going to perform very well.



    -And does anyone know how much weight is shifted when moving a 455 th400 alum intake back. Like 50lbs per inch back or something like that.

    find yourself a circle track racer. most of them either have electronic scales or they can point you to somebody who has a set. scale your car before you do anything and periodically take it back and rescale it so you can keep track of what you're doing to it.

    also, a circle track stock car guy can help you with set up. you just have to make all of your mods symmetrical left to right where he's going to prefer to bias it to turn left. no stagger for you!

    you can't make a blanket "lbs per inch" statement because the further away from the front cross member the engine/trans assembly gets the more effect it has per inch.



    -Also I heard mid 90s jeep steering boxes work good.

    dunno. never heard about anything but the fast Monte SS boxes mentioned over at Buick Performance. http://www.buickperformance.com/GSteering.htm



    -battery relocate to trunk.


    check. put it on the passenger side and as close to the rear seat as possible. i assume you're normally going to be running solo which is going to bias your car weight ~200lbs to the driver side. you mount it forward to reduce pendulum weight.

    speaking of weight, get everything out of the car that you can. insulation, sound deadener, spare tire, jack, etc. less weight makes everything your car does more gooder. accelleration, weight transfer, maximum cornering speed, etc. best would be a stripped interior with an aluminum racing seat. but that would kind of tip the rice boys off, don't you think? :laugh:


    something else you need to consider is taller front spindles and/or shortening the upper control arm mounts on the frame. the car came from the factory with more distance between the upper and lower frame control arm mounts than between the ball joints on the spindle.

    this means that, in any turn, as the suspension is loaded it subtracts camber ( leans the top of the tire out ) from the outside tire. it can't be overstated how bad this is for cornering.
     
  3. Stubbe

    Stubbe Stubbe

    Thanks, ill get crackin
     
  4. bob k. mando

    bob k. mando Guest

    you're welcome. :TU:

    if you haven't yet, you should check out www.SlingerSuperSpeedway.com most of the boys down there know what they're up too.
     
  5. Truzi

    Truzi Perpetual Student

    I'm not reading you... I'm not reading you...
     
  6. doc

    doc Well-Known Member

    Here is what I did to my car when I made that conversion.
    1. heavy duty shock absorbers all the way around.
    2. I put a 100 lb. truck battery in the right rear of the trunk, just as far back toward the rear bumper as it would go. [think leverage]
    3. install air lift air bags inside the rear springs.
    4. Get familiar with the cars new handeling charicteristcs. It is actually a different car with different manners since you did the swap. Make some runs, start ing out easy and gradually increasing speed untill you learn how it will handel.
     
  7. bob k. mando

    bob k. mando Guest

    I'm not reading you... I'm not reading you...

    what's that ground control? you seem to be brea*zap* *crackle* *pop* up.
     
  8. bob k. mando

    bob k. mando Guest

    GrassRootsMotorSports.com seems to have a fairly useful setup article in their October 2007 issue.

    glancing over the first couple of steps the only thing i noticed that really wouldn't apply to us was their comment about it being very difficult to get much negative camber. this is true for the strut cars that they normally deal with but on a 60's or 70's car you can easily shim yourself over 5 degrees.
     
  9. nekkidhillbilly

    nekkidhillbilly jeffreyrigged youtube channel owner

    i frequent on this forum too

    www.pro-touring.com not alot a buick but enough a bodies to help you out
     
  10. 70 gsconvt

    70 gsconvt Silver Level contributor

    I run Edelbrock IAS shocks on my car and oversize sway bars and stock springs with air bags in the back. My car handles great around the onramps and I've chased more than one 350Z getting on the highway and managed to keep up with them. Then blow by them once we're on the highway.

    If you really want the best of everything and can afford it, you need to bag the suspension. But I believe it's about a $4,000 deal, or more, for the whole car.
     
  11. Re: Newb ? extreme handling cornering.

    it's not possible to use the front motor mount holes in the block without MAJOR firewall mods. the engine wont even set down on the frame pads without hitting the firewall..
     
  12. bob k. mando

    bob k. mando Guest

    it's not possible to use the front motor mount holes in the block without MAJOR firewall mods.

    sledgehammer always worked fine for me.

    [ ooops, did i just say that out loud? :eek::Dou::eek: ]

    granted, i did that setback trick in an Electra. probably more room in there.
     
  13. Stubbe

    Stubbe Stubbe

    Sledge hammer, I had to do a little hammering to get the 455 in, but not much. Not that it was hitting anything when it was in, just the install was much easier with the trans tunnel front/firewall indented a little.
     
  14. RAMKAT2

    RAMKAT2 Randy

    Well, just because you can't afford a high dollar chassis doesn't mean that you can't learn something from them. While I was at the Goodguys meet at Kansas Speedway in early September with Mark Macoubie (GSXNUT here on the board) we stopped by the Roadster Shop booth and they had a new "G-Machine" chassis for the 64-72 "A" body GM cars that was unbelievable! They call their new division "RS Performance Concepts". You might never be able to afford a chassis like that one, but you can see the types of modifications that they made to get an "a" body car to handle like a SCCA racer. Check out their website at www.roadstershop.com. You know, 15K for a chassis is waaaaay out of reach for nearly all of us, but a guy can dream can't he?!!! By the way, I recommend www.pro-touring.com as well. It is great place for info on g-machines, even if it seems like it is overun with camaro's. Check it out!
     
  15. sailbrd

    sailbrd Well-Known Member

  16. tlivingd

    tlivingd BIG BLOCK, THE ANTI PRIUS

    I just bolted in the 94 Jeep Grand Cherokee box (all 4x4) and 85 chevy full size pickup rag joint (2wd models only) fits perfectly.

    only problem you may have is the metric o-ring fittings in the new box. (they sell converters for factory hoses.) oh and to change the orafice inside your stock pump. I need to find some GN hoses though (as I'm using a GN power steering pump.) I hope the GN uses the right size o-ring fittings
     
  17. gsxnut

    gsxnut Well-Known Member

    These are a few of the things that I used on my car and it handles well. I am going to go in a biggest bang for the buck order

    1. Educate yourself. This is free for the most part but if you are looking for a good start you can get the book "How to Make Your Car Handle" by Fred Puhn. this is an excellent book to help you understand suspensions, how they work and what can be done to make a car handle better.

    2. Remove all the excess weight you can think of. If you want to get crazy there are a lot places to take out weight but some items can make the car less comfortable on the street like removing all the sound deadening materal thorugh the car, removing air conditioning, the radio, even drilling holes in the window crank pieces. Also, remove your spare tire for autocrossing or on the street when you are staying close to home or have good buddies to pick you up.

    3. Modify your camber and caster. You want to get more agressive with it than the stock setting. The bad thing is the more aggressive you get the more wear you will see on the insides of your tires. The cost to take it to a shop to get this done is about $100.00

    4. Box the frame / install a roll bar. Both will help with the rigidity of the car and are realatively inexpensive if you can do the welding yourself. I think you can do this for about $300.00 total if you can do the welding yourself.

    5. Stiffer springs in the front are a must. I went 580 lb but that is middle of the road. If you are interested in cornering I would go with a 650+ spring. It will ride hard but it will help you with your front heavy car. I think you are looking at about $200 for the front pair of springs. The rears can be a little stiffer but if you make them to stiff you will loose articulation with the suspension and you will start picking up the rear wheels around corners. Not a good thing. I would also go with an inch lower in the front and 3/4" in the back. It is good to get the car lower but if you get it too much lower without changing the other suspension componants you will start to effect camber and caster.

    6. Larger Sway bar in the front sway bar. Hotchis makes a 1 3/8" hollow sway bar for about $250 that I used. It has two advantages. It is way stiffer than the stock sway bar and it weighs a lot less.

    7. Quick ratio steering gear. You can pick a a rebuilt unit with camaro internals for $225 from Lars Corp. http://cgi.ebay.com/ebaymotors/ws/e...STRK:MEWA:IT&viewitem=&item=280151022113&rd=1

    Lars was at the Year One Experience and they have nice stuff. The good thing is it a direct replacement and should not affect your bump steer. I have not made this change but it will be the next change I make. It is a real pain to do soloms with the orginal configuration.

    8. New bushings in all the control arms. I think this is around $250 too. I bought new control arms when I did the change but this will help tighten up the suspension so it is not slopping around on you. It will improve your handling.

    9. New wheels and tires. This is a big expense but will give you a huge bang for the buck. A couple things. Buy alloy wheels with larger diameter than stock and wider than stock. The tires should have thinner sidewalls and wider tread with a good handling rating. The wheels are typically lighter and stronger than the orginals meaning less rotating mass and overall weight. The wider wheels give you better contact patch and stickier tires hold the car to the road better. Check out a new corvette. The bad thing is they wear ratings are really bad so the tires do not last long especailly if you are doing hard cornering. If you are racing only get hoosiers but if you are on the street the biggest bank for the buck from what the SSCA guys say are Kumo's. I would go with 9.5" or 10" wide wheels with the wides tire that will fit without rubbing. I don't know what that is on your car but I am guessing you can be in the 275 range all the way around. Wheels and tires will most likely run you $1500.00 or more.

    10. New body Bushings. $150.00. This make the car more rigid which is one thing you want to do. Less body flex is a good deal.

    11. Adjustable shocks are also a good add at a descent price. I think you can get a set of billsteens or koni's for about $400.00. They add adjustability to your suspension setup.

    12. Boxed rear control arms, adjustable rear control arms and rear sway bar. I really like H&R PartsNStuff rear suspension because it ties directly to the frame and not the control arms but may not be neccessary. I think you can box the arms yourself to start. I think the H&R stuff is around $700 but not sure about that.

    13. Tubular front control arms, drop spindals, I bought the Global West negative roll system which will put you back about $1500 I think. I like it and it works as advertised. What I do not like is the ride height is higher than I would like but they say it needs to be that way to make the geometry work out. They are very knowledgable and can also help you pick out springs and other suspension componants. http://www.globalwest.net/

    14. Bigger brakes always help too. It won't make you turn any better or accelerate any faster but the way to be quicker on the track is to be able to slow down later so good brakes are always a good thing. This is very true if you have upped the power on your car. If you still have stock brakes you will see brake fade very fast. Use DOT 4 brake fluid to help prevent boiling the brakes if you are doing racing with lost of braking involved. A good set of brakes will run you anywhere from $1000 for 12" to $3000 for a 4 wheel disk with 15" fronts and 13" rears. I currently have 13" front on the GSX and they work very well and have helped make the car more comptative at autocross. They cost me about $1600.00.


    My current setup
    Global west front upper and lower control arms with negative roll system
    580 lb front springs, stock rated back springs
    Koni adjustable shocks on all 4 wheels
    Wilwood 13" disc brakes in the front, stock drum in the rear
    American TTII 17" x 8" with 245/45/17 Bridgestone Potenza SO3 tires (could have gone bigger front and back)
    Hotchiks 1 3/8" hollow front sway bar
    Metco Motorsports billet rear and adjustable upper rear control arms (Really like them, they are rock solid and look sweet too)
    Air bags in the back running 10-15 lb in the back
    No weight reduction

    Mark
     
  18. gsxnut

    gsxnut Well-Known Member

    Here are a couple pictures of my GSX in action. A couple of them were taken recently by Randy (RAMKATZ2). thanks for the pics Randy. I still owe you a CD.

    Mark
     

    Attached Files:

  19. gsxnut

    gsxnut Well-Known Member

  20. Stubbe

    Stubbe Stubbe

    Whats the conslusion on handleing and airbag setups. I am building a frame in a few weeks, so far the build is boxed frame, added crossmembers. Dump an weight I can off of it. Boxing the control arms. New bushings. Custom rear control arms, adjustable.

    So the real question is airbags, or coilovers?
     

Share This Page