Page 4 of 21 FirstFirst 1234567814 ... LastLast
Results 61 to 80 of 410

Thread: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

  1. #61
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by Vigo View Post
    As far as i can tell, what glh875 is describing is that the squat/rotation 'softens' the hit which can be helpful if you are on the edge of spinning your slicks. A car with no give in the rear suspension would be like a sidewall that doesn't wrinkle on the slick. Of course, if you have enough traction from the slicks, limiting that suspension movement should incrementally help right up to the point where you start spinning the slicks.


    I understand what he is saying.



    But lets say a vehicle is on a glass smooth surface with the proper traction the suspension becomes un-neccessary period. A vehicles power will only be able to overcome traction to a certain point.
    Example
    My son has a Razor-Ground-Force-Drifter-Electric-Go-Kart which does not have any suspension. If he is in it, it will spin the tires when he takes off. If my fata$$ is in it, it just takes off, hence more weight being over the tires causing them to build more traction. I realize it is faster once it gets moving with him in it(power to weight) but it launches much faster with me in it.


    here is a good read:
    "
    When people think of automobile performance, they normally think of horsepower, torque and zero-to-60 acceleration. But all of the power generated by a piston engine is useless if the driver can't control the car. That's why automobile engineers turned their attention to the suspension system almost as soon as they had mastered the four-stroke internal combustion engine. The job of a car suspension is to maximize the friction between the tires and the road surface, to provide steering stability with good handling and to ensure the comfort of the passengers. In this article, we'll explore how car suspensions work, how they've evolved over the years and where the design of suspensions is headed in the future.


    "If a road were perfectly flat, with no irregularities, suspensions wouldn't be necessary. But roads are far from flat. Even freshly paved highways have subtle imperfections that can interact with the wheels- of a car. It's these imperfections that apply forces to the wheels. According to Newton's laws of motion, all forces have both magnitude and direction. A bump in the road causes the wheel to move up and down perpendicular to the road surface. The magnitude, of course, depends on whether the wheel is striking a giant bump or a tiny speck. Either way, the car wheel experiences a vertical acceleration as it passes over an imperfection. Without an intervening structure, all of wheel's vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then, under the downward force of gravity, the wheels can slam back into the road surface. What you need is a system that will absorb the energy of the vertically accelerated wheel, allowing the frame and body to ride undisturbed while the wheels follow bumps in the road."


    With all this being said, I realize that some give can be helpful, but too much can also be detrimental.

  2. #62

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    I am also racing a first gen. G body, mine is a auto trans, I'm assuming yours is manual? and it would make some difference, But anyway I have found on my car the rear air shock/with rebound travel limiters work very well(air shocks, not bags) with soft front springs on coil-overs.
    Set the front spring as low as possible as to let the weight of the front rest on the jounce bumpers if that is possible with your set-up.
    I run my rear air shocks with 180psi, and I also remove the rear coil spring as they do nothing but take up space and add weight. Just make sure your travel limiters are very strong.
    And as has been pointed out, lower the whole car as much as you can.
    With this set-up, on a well prepped track I can do 1.58's -1.62's consistently. @2300lbs, 26"x7.5" Hoosiers.
    If you ever install a "wheelie bar" then I would want very soft springs in the rear to allow the car to instantly squat onto the bar, and then I would also stiffen up the front somewhat. Also I am still using the factory 84 lower control arms with poly bushings, and factory K member.

    Hope this helps, Warren
    Worlds fastest 8 Valve; best 1/8 ET-6.2 sec. best 1/8 speed-119.70 Best MPH 145.5, Best 1/4 ET 9.73 sec. @144.26mph. 8 valve NO NITROUS!!

  3. #63
    turbo addict
    Join Date
    Jan 2006
    Location
    Everett, WA
    Posts
    6,348

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by glhs875 View Post
    Actually, the stiffer the rear, the sooner the weight will be transferred to the rear (been there, done that). As long as there is movement (squat), no weight is actually shifted to the rear until the squat stops. Lower ride height and longer wheel base transfers less weight to the rear as well. I'm giving away some of my secrets that allowed me to cut 1.9 60's on 300 tread wear tires. I plan on 1.8's or better with the same type of tire whenever I get it going again!
    I understand what you are trying to get at.

    With the stiffness of the rear suspension, the wheelbase is what is critical here. You DO want a rear suspension that controls the squat of the car. Absolutely you want some squat to help reduce some shock to the entire system. However, consider this, that rotation happens around the CG and is also somewhat a function of the front suspension geometry as well. The rotation is wasted energy that could be transferred to forward motion. So, limiting the amount of rotation (squat) in theory should increase the efficiency of the car's motion upon launch and gear shifts.

    As for weight transfer not happening until the squat ends...this is false. The car is rotating around the CG. This means that some weight is being transferred to the rear of the car. This is basic physics and cannot be cheated. For example, to find the height of the CG of a car you jack up either the front or the back higher than the other end. All the wheels are on scales. You can then figure out the height of the CG as long as you know the initial weight bias of the car. This simulates the action of launching or even stopping the car. Now, if the rotational rate is so great that when the suspension bottoms out that the momentum can actually cause a rotation about the rear wheels, THIS is when you loose traction. Control the rate of squat and you can all but eliminate this issue.

    I agree that getting the nose down on the ground as much as possible is good not only for weight transfer, but also aerodynamics. Having a slight forward rake to the car is actually not a bad thing, however more than a few degrees has the potential of being detrimental. Land speed cars almost always have some sort of rake to them.

    I think we all agree that suspension setup is key to getting good launches.

  4. #64
    Moderator Turbo Mopar Staff Vigo's Avatar
    Join Date
    Feb 2006
    Location
    San Antonio,TX
    Posts
    10,789

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Well, today i learned you can air up air shocks to 180psi and not worry about losing control at 140mph when one pops and changes your front end alignment with massive rear sag. Woah.

    Dont push the red button.You hear me?

  5. #65
    turbo addict
    Join Date
    Dec 2005
    Location
    Woodville Ala.
    Posts
    1,710

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by Reaper1 View Post
    I understand what you are trying to get at.

    With the stiffness of the rear suspension, the wheelbase is what is critical here. You DO want a rear suspension that controls the squat of the car. Absolutely you want some squat to help reduce some shock to the entire system. However, consider this, that rotation happens around the CG and is also somewhat a function of the front suspension geometry as well. The rotation is wasted energy that could be transferred to forward motion. So, limiting the amount of rotation (squat) in theory should increase the efficiency of the car's motion upon launch and gear shifts.

    As for weight transfer not happening until the squat ends...this is false. The car is rotating around the CG. This means that some weight is being transferred to the rear of the car. This is basic physics and cannot be cheated. For example, to find the height of the CG of a car you jack up either the front or the back higher than the other end. All the wheels are on scales. You can then figure out the height of the CG as long as you know the initial weight bias of the car. This simulates the action of launching or even stopping the car. Now, if the rotational rate is so great that when the suspension bottoms out that the momentum can actually cause a rotation about the rear wheels, THIS is when you loose traction. Control the rate of squat and you can all but eliminate this issue.

    I agree that getting the nose down on the ground as much as possible is good not only for weight transfer, but also aerodynamics. Having a slight forward rake to the car is actually not a bad thing, however more than a few degrees has the potential of being detrimental. Land speed cars almost always have some sort of rake to them.

    I think we all agree that suspension setup is key to getting good launches.
    I have to agree with you that some of the weight is being transferred while suspension movement is taking place, the exact amount and how quickly will vary with different spring rates. although I still stand on not all of the weight transfer that is going to happen will be realized until the suspension stops moving, as the spring/suspension movement will be soaking up some of the weight.

  6. #66
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by Warren Stramer View Post
    I am also racing a first gen. G body, mine is a auto trans, I'm assuming yours is manual? and it would make some difference, But anyway I have found on my car the rear air shock/with rebound travel limiters work very well(air shocks, not bags) with soft front springs on coil-overs.
    Set the front spring as low as possible as to let the weight of the front rest on the jounce bumpers if that is possible with your set-up.
    I run my rear air shocks with 180psi, and I also remove the rear coil spring as they do nothing but take up space and add weight. Just make sure your travel limiters are very strong.
    And as has been pointed out, lower the whole car as much as you can.
    With this set-up, on a well prepped track I can do 1.58's -1.62's consistently. @2300lbs, 26"x7.5" Hoosiers.
    If you ever install a "wheelie bar" then I would want very soft springs in the rear to allow the car to instantly squat onto the bar, and then I would also stiffen up the front somewhat. Also I am still using the factory 84 lower control arms with poly bushings, and factory K member

    Hope this helps, Warren
    Warren that is some awesome information I really appreciate it I was wondering what the fastest G body out there was. are you at 2300 pounds with you in it or is that car weight

  7. #67
    Supporting Member Turbo Mopar Contributor Ondonti's Avatar
    Join Date
    Dec 2005
    Location
    Seattle
    Posts
    7,025

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Well to me that body rotation is just the energy of the engine going someplace besides accelerating. Once the car stops rotating (say you hit the bump stops) there is no more softening of the power being applied. With street tires this "jerk" will blow the tires off but with slicks they will grab again if your setup is right (not launching too hard for your traction) and we should know that some slip with your slicks is a good thing coming out of the hole. You don't want to be slipping down the track once you are in the powerband. If your car stays squated down in the back I can't see this being good for anything in a FWD. I know what side of the teeter totter the weight is concentrated on and therefore the traction potential. Same reason FWD cars put their weight bars for real race classes as far FWD as possible. The way I think of a teeter totter, you can make it tip one direction by throwing energy into it even if the side that will move down weighs much less. Obviously the weight does not all go into the rear so that means you have control! I violent ending of weight transfer is not the same cause of traction loss as is a lack of proper weight on the front end. The violent end of weight transfer could be compared to dumping your clutch, you get a torque spike and I am sure you could see that on the dyno (dumping clutch). This is not power that is freshly generated but the release of stored energy.

    Best setup for FWD cars is moving all weight FWD, we know that, to think the suspension would be better off letting the whole car tip backwards is wrong. Simply take that to the extreme and you have your proof. I think a lot of people avoid bogs with excessive weight transfer so they misinterpret their success for improved traction. People dead hooking or applying power too hard on a solid suspension setup also give credit to the wrong thing. Junk suspension is like the very poor mans slipper clutch. Makes your safer and more consistent but not optimal.
    Brent
    GREAT DEPRESSION RACING
    1992 Duster 3.0 The Junkyard- Now - Megasquirt II/Extra. OEM 10:1 3.0 + funny business
    - Old - 11.5@125 22psi $90 Stock 3.0 Junk Motor - 516whp 519wtq 20psi 91 oct built 3.0 stock n/a computer
    1994 Spirit 3.0 - 12.3@113 15 psi - Daily Holset He341 280whp 304ft/lb @10psi
    1994 Spirit 3.0 a670 - Wife's - Disassembled
    1990 Spirit 3.0 E.S. 41TE
    1993 Spirit 3.0 E.S. 41TE
    1994 Duster 3.0 A543
    1990 Lebaron Coupe 2.2 TII non IC, T1 31TH
    1981 Starlet KP61 Potential driver, 1981 Starlet KP61 Parts, 1983 Starlet KP61 Drag
    1998 Dodge 12v Cummins 47re 4x4 4dr longbed. No fuel plate. Mack plug, AFC & Spring mods. Boost elbow.

  8. #68

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by Vigo View Post
    Well, today i learned you can air up air shocks to 180psi and not worry about losing control at 140mph when one pops and changes your front end alignment with massive rear sag. Woah.
    Just as a test I let all the air out of one shock, the other remaining shock easily supports the rear as if they were both pressured up. Also I let all the air out of both, the back just falls down and bottoms out the shocks but the tires still do not rub.
    I fill them to the highest pressure my shop air compressor is set to somewhere around 170-180psi.

    - - - Updated - - -

    Quote Originally Posted by turboshelbys View Post
    Warren that is some awesome information I really appreciate it I was wondering what the fastest G body out there was. are you at 2300 pounds with you in it or is that car weight
    That is with me in the car.
    Worlds fastest 8 Valve; best 1/8 ET-6.2 sec. best 1/8 speed-119.70 Best MPH 145.5, Best 1/4 ET 9.73 sec. @144.26mph. 8 valve NO NITROUS!!

  9. #69

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by Ondonti View Post
    Well to me that body rotation is just the energy of the engine going someplace besides accelerating. Once the car stops rotating (say you hit the bump stops) there is no more softening of the power being applied. With street tires this "jerk" will blow the tires off but with slicks they will grab again if your setup is right (not launching too hard for your traction) and we should know that some slip with your slicks is a good thing coming out of the hole. You don't want to be slipping down the track once you are in the powerband. If your car stays squated down in the back I can't see this being good for anything in a FWD. I know what side of the teeter totter the weight is concentrated on and therefore the traction potential. Same reason FWD cars put their weight bars for real race classes as far FWD as possible. The way I think of a teeter totter, you can make it tip one direction by throwing energy into it even if the side that will move down weighs much less. Obviously the weight does not all go into the rear so that means you have control! I violent ending of weight transfer is not the same cause of traction loss as is a lack of proper weight on the front end. The violent end of weight transfer could be compared to dumping your clutch, you get a torque spike and I am sure you could see that on the dyno (dumping clutch). This is not power that is freshly generated but the release of stored energy.

    Best setup for FWD cars is moving all weight FWD, we know that, to think the suspension would be better off letting the whole car tip backwards is wrong. Simply take that to the extreme and you have your proof. I think a lot of people avoid bogs with excessive weight transfer so they misinterpret their success for improved traction. People dead hooking or applying power too hard on a solid suspension setup also give credit to the wrong thing. Junk suspension is like the very poor mans slipper clutch. Makes your safer and more consistent but not optimal.
    My car ET's the best when I can get just a little wheel speed on the first hit; It springs up "on the tire", then spins about a revolution, while the car catches up to the spin. If that makes any sense.
    Worlds fastest 8 Valve; best 1/8 ET-6.2 sec. best 1/8 speed-119.70 Best MPH 145.5, Best 1/4 ET 9.73 sec. @144.26mph. 8 valve NO NITROUS!!

  10. #70
    turbo addict
    Join Date
    Dec 2005
    Location
    Woodville Ala.
    Posts
    1,710

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Here is a website that hits on what I have been saying about weight transfer. www.turnfast.com in the articles topics go to handling and then go to weight transfer at the top of the page to read the article.

  11. #71
    Moderator Turbo Mopar Staff Vigo's Avatar
    Join Date
    Feb 2006
    Location
    San Antonio,TX
    Posts
    10,789

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Just as a test I let all the air out of one shock, the other remaining shock easily supports the rear as if they were both pressured up. Also I let all the air out of both, the back just falls down and bottoms out the shocks but the tires still do not rub.
    I fill them to the highest pressure my shop air compressor is set to somewhere around 170-180psi.
    Glad you did those tests! I guess for you it is a function of light weight and skinny tires being used purely on a flat surface making it workable as far as safety/reliability. Thanks for the additional info.

    Dont push the red button.You hear me?

  12. #72
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by glhs875 View Post
    Here is a website that hits on what I have been saying about weight transfer. www.turnfast.com in the articles topics go to handling and then go to weight transfer at the top of the page to read the article.
    That's a good read, thank you.

  13. #73
    turbo addict
    Join Date
    Jan 2006
    Location
    Everett, WA
    Posts
    6,348

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by glhs875 View Post
    I have to agree with you that some of the weight is being transferred while suspension movement is taking place, the exact amount and how quickly will vary with different spring rates. although I still stand on not all of the weight transfer that is going to happen will be realized until the suspension stops moving, as the spring/suspension movement will be soaking up some of the weight.
    Correct, not all of the possible weight transfer can happen until the suspension stops moving...be it that it is in equilibrium from opposing forces in its normal operating range, or that it bottoms out and the spring rate becomes infinite.

    The spring/suspension aren't soaking up "weight", they are soaking up force and energy. Ultimately, as the article you posted says, you want to set up the suspension such that it controls the rate of the transfer of energy such that it does not upset the balance of the vehicle at the edge of traction (in this case the launch). Some cars want that control rate super fast, others need it much slower. Certain set-ups will have a baseline approach as to how best to make it work, but for obvious reasons each one will be slightly unique, so there is no real "cookie cutter" answer as to how to best set up the car. In the end it's trial and error.

  14. #74
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    I appreciate every ones comments and information on the suspension topic, but can we move it to another thread? I would like to get back on topic of my build

  15. #75
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Painted the fiberglass hatch and cut the Lexan to fit. Have to install a middle support for the Lexan. Trimmed 2-3 lbs more off the rear bumper as well.

  16. #76
    boostaholic
    Join Date
    Oct 2008
    Location
    Palmerton PA
    Posts
    1,264

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Wow fiberglass hatch with lexan! Awesome! That had to cut a ton of weight out. Any idea on your race weight?

  17. #77
    turbo addict
    Join Date
    Apr 2009
    Location
    Detroit, MI
    Posts
    1,770

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    What are your goals quarter mile wise???
    [SIGPIC][/SIGPIC]

  18. #78
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    Quote Originally Posted by lengel View Post
    Wow fiberglass hatch with lexan! Awesome! That had to cut a ton of weight out. Any idea on your race weight?
    If memory serves old hatch was 85lbs(latch shocks brackets etc). Fiberglass hatch is 5lbs, lexan was 5lbs and brackets screws were another 3lbs, total 13lbs. I have not weighed the wing yet. going to be lightening that too.

    I am working on the hood now.


    Old hood was 55lbs(by itself), this one weighs 15lbs

    I will be weighing and setting up my suspension shortly, but best guess is sub 2000lbs.

    - - - Updated - - -

    Quote Originally Posted by 85boostbox View Post
    What are your goals quarter mile wise???
    as fast as it will take me

    seriously though, I was hoping for a 10.99 or better.

  19. #79
    Hybrid booster
    Join Date
    Jan 2007
    Location
    Merrimack, NH
    Posts
    869

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    one more shot


    I will be moving the 3gallon fuel cell to the front also

  20. #80

    Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance

    As I recall, the Hairy Glass parts were not intended for a stock sized car. How has it been to trim down to fit?

Page 4 of 21 FirstFirst 1234567814 ... LastLast

Similar Threads

  1. For Sale The Hoopty 1986 Dodge Omni GLH-T DOHC turbo
    By Ubmbass in forum Cars
    Replies: 0
    Last Post: 09-11-2013, 06:28 PM
  2. 1986 Dodge Daytona Turbo Z C/S
    By 86daytonat_top in forum Cars
    Replies: 2
    Last Post: 10-31-2006, 09:15 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •