94eg!

iTrader: (2)

I'm thinking about going to the drag strip this Wednesday and I would like some quick tips to get the car a little better optimized for strip use. I don't know much about drag-racing setups, so any tips could help (shock-settings, disconnecting sway-bars, etc...)

Here is the setup:
- 94 Civic CX
- 97 B18C (type R) w/ velocity stack intake & 2.5" exhaust (2.25" cat)
- Koni Sport shocks (fronts set same as rears)
- GC coil-overs 400f/250r
- GC upper mounts in front
- 2.5" lowered (I don't think I'll be changing this because of alignment)
- 205/40/16 tires w/ OEM PSI f&r (I forget the exact numbers)
- 24mm front sway
- 14mm rear sway

I'm also thinking about advancing ignition timing to 18* BTDC (from 16*) and upping the fuel stability with a 100oct/91oct mix...

b18LS

hmmm, those soft rear and stiff front spring rates might hurt you. If you can, I'd raise the car up in the rear, to get the most weight over the front wheels. If its possible swap in a softer front spring, or a stiffer rear. I'd be hard to do anything that wont cause you to need another alignment. Drop your pressures to 18 PSI or so and run them at 40 in the rear. I dont think sway bars will effect your launch much, although drag racers might want to chime in.

dinko

are your springs the same length in the front and rear?

PIC Performance

Swaybars will have little to no effect in straight-line handling, assuming the road is reasonably smooth (like a dragstrip should be).

You could max out front rebound damping to slow down the rearward load transfter under launch but I'm not sure how much that really helps during drag racing. If you've only got rebound damping and no compression, that's pretty much the extent of what you can do with the dampers then.

Adding more front rake (raising the rear end) should also help keep load on the front. you probably know about tire pressures and camber.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b16gs &raquo;</TD></TR><TR><TD CLASS="quote">hmmm, those soft rear and stiff front spring rates might hurt you. If you can, I'd raise the car up in the rear, to get the most weight over the front wheels. If its possible swap in a softer front spring, or a stiffer rear. I'd be hard to do anything that wont cause you to need another alignment. Drop your pressures to 18 PSI or so and run them at 40 in the rear. I dont think sway bars will effect your launch much, although drag racers might want to chime in.</TD></TR></TABLE>

Thanks for the PSI recommendations. I don't have the option to switch springs or change heights right now. I understand that my setup is optimized for the streets. I just thought I would throw the question out there...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dinko &raquo;</TD></TR><TR><TD CLASS="quote">are your springs the same length in the front and rear? </TD></TR></TABLE>

No. The lengths are GC OTS front & rear. I have no idea why the rates are not OTS though since I ordered them & had 'em installed many years before I knew thing-1 about suspension...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PIC Performance &raquo;</TD></TR><TR><TD CLASS="quote">You could max out front rebound damping to slow down the rearward load transfter under launch but I'm not sure how much that really helps during drag racing. If you've only got rebound damping and no compression, that's pretty much the extent of what you can do with the dampers then. </TD></TR></TABLE>

Now I had thought it might be better to make the front rebound very soft to keep the tires in contact with the road surface when the weight shifts rearward. From what your saying this is not the case. Can you explain the reason a little more more please?

vtecvoodoo

Just turn your hat backwards.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtecvoodoo &raquo;</TD></TR><TR><TD CLASS="quote">Just turn your hat backwards. </TD></TR></TABLE>

PIC Performance

I wasn't thinking of it that way. Typically I only think of rebound damping as controlling the sprung weight of the car and not the unsprung. I only thought of the rebound damping functioning to resist the extension of the front suspension as the car tries to squat, thereby slowing the transfer of load off the fronts and onto the rears.

hayabusa160

i usually just turn the konis all the way up in the rear drop front tire pressure to like 18psi.

thats pretty much all u can do.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PIC Performance &raquo;</TD></TR><TR><TD CLASS="quote">I wasn't thinking of it that way. Typically I only think of rebound damping as controlling the sprung weight of the car and not the unsprung. I only thought of the rebound damping functioning to resist the extension of the front suspension as the car tries to squat, thereby slowing the transfer of load off the fronts and onto the rears. </TD></TR></TABLE>

Ahh, that makes good sense. Thanks

I was PM'ing with vtecvoodoo, and I found out about a part that might really make a difference at the drag strip. They are called "spring-rubbers". It's basically a hard rubber ring with grooves cut in the top & bottom. It's split so that you can feed it between the coils of a spring, and effectively render a single coil non-functional (the rubber does have some rate too). This can substantially stiffen the spring and also raise the ride height. I f I can locate a pair of these localy, I would like to try them out in the rear.

The rear has 250lb springs with 1-1/8" between coils, and 3.75 coils total. With one spring rubber on each side, I figure I could get a pretty substantial bump in spring rate, as well as rake. All I need to bring to the track is a jack, and some silicone spray lube so they'll pop easily into place. These are used pretty frequently in Nascar, and Motocross...

Anybody ever tried these (From searching I've found that this can a touchy subject )?

PIC Performance

I think those full rings are actually OK, and it's the smaller wedge-type things that people object to. if I remember correctly, someone said that the small ones could localize load on only small sections of the spring wherever they were put, hurting the coils. Those full rings look like they'd do a better job of spreading the load around. I wish I could remember who said it... I want to say CRX_Lee.

MyEG6

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94eg! &raquo;</TD></TR><TR><TD CLASS="quote">

</TD></TR></TABLE>

Looks cool. I can see the theory behind it. Looks dangerous to me but highly probable since you say it is used in other circuits.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MyEG6 &raquo;</TD></TR><TR><TD CLASS="quote">

Looks cool. I can see the theory behind it. Looks dangerous to me but highly probable since you say it is used in other circuits.</TD></TR></TABLE>

It would only be dangerous for prolonged use where one might break apart and fall out while the other remained in place. This would result in one stiff & one soft spring in the rear.

This would not be the case if your just poping em in for a few passes down the drag-strip...

TunerN00b

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94eg! &raquo;</TD></TR><TR><TD CLASS="quote">It would only be dangerous for prolonged use where one might break apart and fall out while the other remained in place. This would result in one stiff & one soft spring in the rear.

This would not be the case if your just poping em in for a few passes down the drag-strip...</TD></TR></TABLE>

Also, be careful about using them in the rear. Not sure about all Hondas, but my Integra seems to want to toe out when I raise the rear. Last thing I would want to try is taking a pass with toe out in the back.

I've searched for information on spring rubbers a couple of times now, however have never found anything that would imply that they would actually be helpful for my needs. They seem to be more useful as a slight rate change for fine tuning, than to radically alter spring rates for different needs. The one vendor I emailed said that his spring rubbers were only good for aprox. 25 lbs/in increments, and that I'd have to try to fit a bunch back there (he cautioned against trying more than 2) for the type of increase in rate I wanted.

I wanted to try using them to stiffen up the rear of my daily driver Integra for autocross / HPDE use, so I wouldn't have to run the high rear rates daily. Still looking for an acceptable solution...

dinko

I think they'd almost have to "feel" like plastic to give you anything over 25lbs/in increments. If its a full ring, wouldn't you have to take the whole spring out of the car to install these?

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dinko &raquo;</TD></TR><TR><TD CLASS="quote">If its a full ring, wouldn't you have to take the whole spring out of the car to install these? </TD></TR></TABLE>

The picture of the full ring is how they come, but your supposed to make a cut at one point so it will feed into the side of the coil like the installed picture...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TunerN00b &raquo;</TD></TR><TR><TD CLASS="quote">

Also, be careful about using them in the rear. Not sure about all Hondas, but my Integra seems to want to toe out when I raise the rear. Last thing I would want to try is taking a pass with toe out in the back.

I've searched for information on spring rubbers a couple of times now, however have never found anything that would imply that they would actually be helpful for my needs. They seem to be more useful as a slight rate change for fine tuning, than to radically alter spring rates for different needs. The one vendor I emailed said that his spring rubbers were only good for aprox. 25 lbs/in increments, and that I'd have to try to fit a bunch back there (he cautioned against trying more than 2) for the type of increase in rate I wanted.

I wanted to try using them to stiffen up the rear of my daily driver Integra for autocross / HPDE use, so I wouldn't have to run the high rear rates daily. Still looking for an acceptable solution...</TD></TR></TABLE>

Well, I would think the resulting rate-change would have more to do with the spring itself than the rubber part your installing. Obviously boosting a single coil on a 3.75 coil spring is gonna make a much bigger difference than boosting a single coil on a 8 coil spring. I've seen some for sale that have a durometer rating of up to 70. Unfortunately I have nothing to compare that to, so I don't really know how stiff that is.

Too much Toe-Out would definitely be a concern...

slammed_93_hatch

limit straps on the front suspension??? I am pretty sure i have seen them used before.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch &raquo;</TD></TR><TR><TD CLASS="quote">limit straps on the front suspension???</TD></TR></TABLE>

I'm not quite sure what your asking or why you brought this up. Limit straps keep the springs from expanding. Spring rubbers keep them from compressing. Exact opposite I guess...

slammed_93_hatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94eg! &raquo;</TD></TR><TR><TD CLASS="quote">

I'm not quite sure what your asking or why you brought this up. Limit straps keep the springs from expanding. Spring rubbers keep them from compressing. Exact opposite I guess...</TD></TR></TABLE>

You put limit straps on the front suspension is a different way of doing the spring rubber on the rear.

I think some one sells a kit for honda's.

either on is going to give you the same result same, result just a different way of getting there.

94eg!

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch &raquo;</TD></TR><TR><TD CLASS="quote">

You put limit straps on the front suspension is a different way of doing the spring rubber on the rear.

I think some one sells a kit for honda's.

either on is going to give you the same result same, result just a different way of getting there.</TD></TR></TABLE>

Ahhh, thanks for your insight. I kinda started thinking about that after I posted that last message. I'm sure the effects would still be a little different for both setups. The limiting straps would cause the car to squat in the back on launch, while the spring rubbers would produce lift in the front...

I guess it comes down to whatever is cheaper and/or easier to work with in the end...

slammed_93_hatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94eg! &raquo;</TD></TR><TR><TD CLASS="quote">Ahhh, thanks for your insight. I kinda started thinking about that after I posted that last message. I'm sure the effects would still be a little different for both setups. The limiting straps would cause the car to squat in the back on launch, while the spring rubbers would produce lift in the front...

I guess it comes down to whatever is cheaper and/or easier to work with in the end...</TD></TR></TABLE>

This is were i get confused because i haven't looked into it much. But weight transfers no matter the spring rate, its still transfering (i think).

I have heard of FF drag cars using limit straps though.

PIC Performance

the same amount of load will transfer unless you change your spring rates. you can change the rate at which it moves, that's about it.

TunerN00b

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PIC Performance &raquo;</TD></TR><TR><TD CLASS="quote">the same amount of load will transfer unless you change your spring rates. you can change the rate at which it moves, that's about it.</TD></TR></TABLE>

The same load will transfer for a given acceleration, regardless of the spring rates. How much the body squats to the transfer is determined by the rates.

Its similar to how you transfer the same amount of weight inside to outside in a corner regardless of the rates, but the amount of body roll is determined by the rates.

Since a drag car doesn't need droop travel in the back, why not use limit straps in the back to massively preload the spring? Thats about the only reliable way I know of to temporarily increase spring rate. What I mean by this is, crank down the spring with the limit strap, and then raise the spring perch to compensate height, until its so stiff that you essentially have little to no rear suspension. If you preload a spring with 500 lbs, it will take 500 lbs of weight before it starts to move. Preload 1000 lbs, and you might never use more than 1/4" of shock travel during the run. Just an idea, and probably an insane one too, so feel free to ignore me.

PIC Performance

i see i see.

aaah in the rears, you wouldn't even have to use limit straps would you? you could just raise those collars up super high and compress the spring that way. more or less the same thing it sounds like... ?

slammed_93_hatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TunerN00b &raquo;</TD></TR><TR><TD CLASS="quote"> If you preload a spring with 500 lbs, it will take 500 lbs of weight before it starts to move. Preload 1000 lbs, and you might never use more than 1/4" of shock travel during the run. Just an idea, and probably an insane one too, so feel free to ignore me.</TD></TR></TABLE>

The first part of that sounds right, but the quoted part is wrong.

if you have a 500lbs spring, for every inch it takes 500 lbs to compress it. even if it is compressed 2 inchs it only takes another 500 lbs to compress it another 1 inch.

If what you said were true then we would be dealing with progressive springs.

This is were the BIG confuse comes in from the whole 'preloading' thing.