Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
Interesting, So you believe there is more loss with a stiffer rear end in a FWD? I would think if a car squats 4-5inchs vs 1-2 inches, the 1-2 inches(less transfer) would run quicker, no?
I can't really comment on the difference in total weight from more or less movement. But a really stiff or locked down rear will transfer the weight immediately whereas the softer rear that allows some squat will allow the car to get moving before the squat stops and then at that point the weight will be transferred. I agree with more weight on the front and also balancing the weight using the scales you mentioned. I think a proper rear shock setting can really come into play as well. I gave up on the air shocks myself.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
glhs875
I can't really comment on the difference in total weight from more or less movement. But a really stiff or locked down rear will transfer the weight immediately whereas the softer rear that allows some squat will allow the car to get moving before the squat stops and then at that point the weight will be transferred. I agree with more weight on the front and also balancing the weight using the scales you mentioned. I think a proper rear shock setting can really come into play as well. I gave up on the air shocks myself.
I am confused a very stiff or lets say solid rear suspension, how does weight transfer? if there is very little to no movement in the rear how can weight transfer? I would think that the "weight" would have to reach a certain "tipping point" before it would affect anything
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
I am attributing some of my knowledge about this to the Mythbusters special on tipping a car:o
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
Interesting, So you believe there is more loss with a stiffer rear end in a FWD? I would think if a car squats 4-5inchs vs 1-2 inches, the 1-2 inches(less transfer) would run quicker, no? Aerodynamics would come into play as well correct? if the rear end dips down, front end comes up, more air under the car, more air forcing the rear end down(longer travel) creating more resistance? I would think and believe a stiffer suspension would provide better times.
I did mention lower ride height helping (aerodynamics, and less total travel). But travel in the rear still helps. Like I said, been there, done that on the stiff/locked rear end. I remember a FWD Chevy Lumina I seen launch at the track one night. It looked like the rear of the car squatted 5 or 6 inches but it left very hard! Got me to thinking/googleing/experimenting.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
I am with you, I will be trading in the old air shock system shortly
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By no means I am not saying that cars cannot launch and fly down the track like that, I would just have to believe that there is some loss there with a loose suspension.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
I am with you, I will be trading in the old air shock system shortly
You will have to tune on the suspension, but I feel the result will be lower 60's. Staging the boost (speed or gear based) helped me as well.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
I would also say this affects standards more than it would automatics, guess i should have started with that;)
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
I am with you, I will be trading in the old air shock system shortly
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By no means I am not saying that cars cannot launch and fly down the track like that, I would just have to believe that there is some loss there with a loose suspension.
The weight is going to be transferred regardless. Delaying/controlling the transfer from allowing some rear travel can help.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
glhs875
You will have to tune on the suspension, but I feel the result will be lower 60's. Staging the boost (speed or gear based) helped me as well.
For sure. Lower 60's means lower 1/4's:thumb: I am trying to save/shave every tenth I can everywhere I can.
My ems-4 has a 2 step, boost by rpm, and boost by gear. Have not been able to start setting that up yet though, hopefully this Sund. at IFO
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
I would also say this affects standards more than it would automatics, guess i should have started with that;)
A manual car is more touchy and much harder to launch. But the same laws of physics still apply.
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Quote:
Originally Posted by
turboshelbys
For sure. Lower 60's means lower 1/4's:thumb: I am trying to save/shave every tenth I can everywhere I can.
My ems-4 has a 2 step, boost by rpm, and boost by gear. Have not been able to start setting that up yet though, hopefully this Sund. at IFO
Use the boost by gear!!! That can do wonders for a 60' and will carry through the 1/4!
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
glhs875
The weight is going to be transferred regardless. Delaying/controlling the transfer from allowing some rear travel can help.
Some weight yes unless the car is totally rigid then nothing is going anywhere. I am just trying to minimize how much. I do realize that there is no stopping all of the transfer.
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Maybe the word I should have used is force and not weight? I guess both apply
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Quote:
Originally Posted by
glhs875
Use the boost by gear!!! That can do wonders for a 60' and will carry through the 1/4!
I'll be using all of them:nod:
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
turboshelbys
Some weight yes unless the car is totally rigid then nothing is going anywhere. I am just trying to minimize how much. I do realize that there is no stopping all of the transfer.
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Maybe the word I should have used is force and not weight? I guess both apply
I remember when I still had my Daytona (manual trans.). I put some rear travel limiters on this car. I would have traction until I felt the limiters come into play and then stop any further squat. At that exact point I would loose traction. Tried it many times to confirm.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
glhs875
I remember when I still had my Daytona (manual trans.). I put some rear travel limiters on this car. I would have traction until I felt the limiters come into play and then stop any further squat. At that exact point I would loose traction. Tried it many times to confirm.
Were you running slicks? what size? how much hp/trq were you making? Just for clarification my race car will always be running slicks. If I lose traction I will be getting wider slicks;)
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I kept it street legal, just so I could drive it to car shows/meets.
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Quote:
Originally Posted by
glhs875
I remember when I still had my Daytona (manual trans.). I put some rear travel limiters on this car. I would have traction until I felt the limiters come into play and then stop any further squat. At that exact point I would loose traction. Tried it many times to confirm.
to me that sounds more like power transfer.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
when you were searching google and such, did you run across any interesting reads on this?
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
I think what glhs875 is trying to say is that you want some sort of rotation come out of the car. Which I completely agree with. You don't want no rotation come out of the car, because then traction strictly comes from the tires, and if that were the case you wouldn't need suspension.
Suspension tuning is going to be key to getting low 60's. Rule of thumb is for every .1 you knock off the 60', is .2 off the e.t.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
85boostbox
I think what glhs875 is trying to say is that you want some sort of rotation come out of the car. Which I completely agree with. You don't want no rotation come out of the car, because then traction strictly comes from the tires, and if that were the case you wouldn't need suspension.
I agree to having some sort of suspension, but I can tell you I definitely want all my power and traction getting to the tires:thumb:
Quote:
Originally Posted by
85boostbox
Suspension tuning is going to be key to getting low 60's.
This is what I was trying to state in the beginning:hail:
The lockdown kit is going to help me do that:nod:
Again, I am not stating this is a fix all or that every body should do it or its for everyone. I was just showing my build and explaining why I did what I did. If it helps me save a tenth, then I am more than happy. My total cost on parts was $18.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
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.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
Reaper1
Ah...so you are using them as limiting straps because you are using air shocks that when filled extend the suspension to the point that it almost (and can) overextends.
I know a few of the "old school" tricks and have used and still use a few. You are right, there is very little wrong with them and they do still work. However, times and knowledge have come a long way and there are methods and parts that do as good, if not a better job. This has a few things going for it: it's simple, it's cheap, it's fairly light, it can work, and you seem to already have an understanding of what it does and how it does it.
I just didn't know the reasoning behind it because I haven't seen people do this in a while.
When I tried to limit the rear end height I kept using the lightest parts I could and they would freakin snap every time before I made a pass for odd reasons like I was forced to drive off a curb for parking reasons or whatever. My air shocks lift the car off the springs when pumped up so they don't really do their job. This ended up with massive squat on launch so the airshocks were not doing their job. I had much better function with simple air bags in the rear springs of my spirit. No need to have limiting straps.
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
Quote:
Originally Posted by
Ondonti
When I tried to limit the rear end height I kept using the lightest parts I could and they would freakin snap every time before I made a pass for odd reasons like I was forced to drive off a curb for parking reasons or whatever. My air shocks lift the car off the springs when pumped up so they don't really do their job. This ended up with massive squat on launch so the airshocks were not doing their job. I had much better function with simple air bags in the rear springs of my spirit. No need to have limiting straps.
Yes that what mine would do also. By no means this being done as a permanent fix. I just needed something better so i can make it to IFO this weekend
Re: 1986 Dodge Daytona Turbo Z T3 DOHC Tuned at FwdPerformance
I'll add my 2 cents to this thread. I've driven hundreds of cars equating to thousands of passes in cars ranging from 80whp to 800whp. When the suspension is tight, the motor mounts are rigid, and the car is properly strapped, except for noise and your own anticipation, they can feel and look like very similar passes. In most cases, I find dyno video's very boring :p That said, when I get in a car on the dyno that I expect to make some power I tend to grip the wheel a little tighter. :eyebrows: Stefan's car is a pleasure to tune on. It's rock solid on the Dyno just the way I like it. Because of the move our dyno has only recently become operational again. My home made above ground tie down apparatus was made from spare metal that was used to transport our new lifts. :) Stefan's car was the first to put the whole system to the test. I wish every car behaved that well. As for suspension, I like to get a car out of the air as much as possible. What's been done here limits (not eliminates) excessive travel in the rear which, should also limit travel of the nose up into the air. 60 foot is critical but, after the eighth, the amount of power it takes to accelerate against the force applied by 100mph+ head wind is incredible. Ideally you have the body as low in the air as possible while leaving the suspension with room to contribute in the fight for traction. As Stefan's setup sits, this mod accomplishes that within the budget allotted.