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Discussion Starter · #1 ·
Thinking of running two stages in the race car this year, one for off the line and one for down track. Could I use two Mallory 685 boxes to control timing and activation? If so, how would one wire the systems? Maybe one on a wot switch and the other on a button? Time delay box between the two? I have all the parts, just curious on your opinions. Thanks in advance -Alex
 

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You'll need only one 685 box...

I'd activate the first kit right off the WOT switch and the second one with the WOT switch & window switch.

How much nitrous are you going to spray?
 

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Discussion Starter · #3 ·
I was thinking 75 in one kit and 100 in the second.so you're saying pull all the timing necessary for both shots with one box? And then run the 2nd kit only through the window switch? That sounds like a winner actually
 

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For a 175 shot I'd run it in a single stage.

Two stage would be perfect for something like 150+100 or 150+150.
 

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Knowing the details of your race car -- engine, suspension/traction enhancements, gearing, TC, weight, would help decide which of Guilliame's suggested options, or possibly another variation, might work best for you.

I agree it's unlikely you'll need full control (window sw + timing retard) for both stages that would dictate more than 1 box.
 

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Discussion Starter · #6 · (Edited)
It's not really a race car per say, more my "race car" in the fold. Stock bottom lt with heads and cam,3800 stall,and 4.11s. The reason I ask is I was debating pulling the kit out of the another car,as I rarely use it, and use it in the "race car",having 2 full kits at my disposal. It'll have stock style suspension and slicks,I was simply going to split the shot up to ensure good traction out of the hole.figured if you got it, use it! I figured 2 685's might make the timing more precise, but if you guys say it shouldn't matter, that sounds good to me.
 

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175 shot i'd spray from the third yellow bulb to the ambulance by the clocks
 

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With that converter, there's no risk in loading the motor at a low rpm with a small shot, so here's what I'd do for a stockish suspension:
Put the first (75) shot on a WOT switch only. Pull 3 degrees from the timing tables of your NA tune. If you find it's blowing the tires off, pull more timing below 5000 rpm till it holds.
Put the 2nd (100) shot on a time delay adjusted to bring it in immediately after the 1-2 shift, and use the Mallory box to pull the additional 4 degrees of timing, and, depending on the strength of your tranny, to cut the spray for the 2-3 and 3-4 shifts.
 

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Lol thanks normlz:) so you second one igniton box as well?
that's all I use and spray 150shot right from the green. granted the wagon as a bit more ballast in the rear to hook with. those wheels up shots are using a small 255 drag radial & 205's up front, stiff Monroe sever service shocks and airlift 1000's in the rear wit umi lca's.

these cars work well and even without trick parts get the job done
 

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that's all I use and spray 150shot right from the green. granted the wagon as a bit more ballast in the rear to hook with. those wheels up shots are using a small 255 drag radial & 205's up front, stiff Monroe sever service shocks and airlift 1000's in the rear wit umi lca's.

these cars work well and even without trick parts get the job done
+1 !!!!!

These cars hook up really well with nothing much done to them. I've been 1.50 with UMI arms and relocation brackets (to compensate for the 3" drop), stiff shocks, both swaybars on and 3.23 gears.

The only reason it hasn't been quicker is because I'd need more power off the line, not because it's traction limited.

One thing people don't usually think about is how the weight of our cars DESTROY the sidewalls on regular slicks. After just a few runs the sidewall on my slicks would be as solid as an old rag and it wouldn't hook. A new set of slicks fixed the problem but it wouldn't last. The slicks were no good even with plenty of thread left. Going to a stiff wall slicks fixed it for me. The difference in how it hooks drives down the track is unbelievable.

Norm, I'm pretty sure you probably would be doing as well are you are now with "real" drag slicks... at least, not for long. :) Our cars really love the stiff walls or radials.

That being said, I see no reason to split a 175 shot into two stages on these cars. With basic traction mods and a good set of tires it should hook.

When I was running nitrous I was spraying a 175 shot right off the line (no minimum RPM on the window switch). All I had were UMI LCA and a good set of tires, it went 1.54 on the 60' and 11.49 @ 117 mph.
 

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Guilliame, those were some mild gears! What converter and tire size were you running with that setup? OP is running a 3800 converter and 4.10's; if the motor has any nuts at all, I have my doubts about holding the full shot out of the hole
I don't have the luxury of not worrying about traction. Mine hits the tires hard enough to 60' in the low 1.4x's on motor only. Even with pulling extra timing at launch, I've never successfully hooked up on the 100 shot even with good track prep.
With my stock motor and hitting the 150 shot right out of the hole, it would 60' mid 1.4x's when it hooked, but it required a good starting line. Was running a SS3600, 4.88 gears and 30" tires then.
OP, it doesn't hurt to try as they suggest. If it blows the tires off, pull timing below 5000 in the table till it hooks up.
 

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Guilliame, those were some mild gears! What converter and tire size were you running with that setup? OP is running a 3800 converter and 4.10's; if the motor has any nuts at all, I have my doubts about holding the full shot out of the hole
I don't have the luxury of not worrying about traction. Mine hits the tires hard enough to 60' in the low 1.4x's on motor only. Even with pulling extra timing at launch, I've never successfully hooked up on the 100 shot even with good track prep.
With my stock motor and hitting the 150 shot right out of the hole, it would 60' mid 1.4x's when it hooked, but it required a good starting line. Was running a SS3600, 4.88 gears and 30" tires then.
OP, it doesn't hurt to try as they suggest. If it blows the tires off, pull timing below 5000 in the table till it hooks up.

When I was running nitrous, I had 4.10's a 3200 rpm stall converter and 28" slicks. It would 60' in the low 1.6x NA and low 1.5x on nitrous. Race weight was 4100 lbs. NA MPH was 108-110, and I would get a 8 MPH bump with a 150 shot.

The 3.23 gears are for the current turbo motor.

1.4x is very impressive especially NA, that's A LOT of power available and the 122 mph trap speed confirms this. I seriously doubt OP has the same power/weight ratio as you do, being a stock bottom end and a street car.

OP: What kind of MPH does the car get NA?
 

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my example was simply to show that with skinny radials, non drag suspension parts and heavy stock wheels. these cars can hook well with 150 shot from green. put another 2" of tire, big and littles and drag shocks/springs for transfer. it would take quite a bit of power to over work one of these cars.
 

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One thing people don't usually think about is how the weight of our cars DESTROY the sidewalls on regular slicks. After just a few runs the sidewall on my slicks would be as solid as an old rag and it wouldn't hook. A new set of slicks fixed the problem but it wouldn't last. The slicks were no good even with plenty of thread left. Going to a stiff wall slicks fixed it for me. The difference in how it hooks drives down the track is unbelievable.
I totally agree, and been there, done that! Unless you have a stiff sidewall you'll most likely be forced to run a lot of air pressure to keep from rolling the sidewall, which means that you have to work the suspension instead, which isn't easy and could be a lot more expensive.

I recommend a progressive controller instead. 175 is not so much that you'd need a 2 stage. I had asked whether or not I should run a 2 stage for up to a 400 shot, and the unanimous answer (from vendors too) was that a progressive control is the better approach. If you don't mind spending less money and having a less complicated setup, then you could have a simple system with more adjustability!
 

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Discussion Starter · #16 ·
Man, this thread took off!thanks to all of you who have contributed.In all honesty guillaume this is my first year running the car and it is a totally new setup. I had planned to use boxed stock arms with airlifts in the rear and a shimmed bar as Gish has suggested. My thought was that using two kits, I can tailor the learning curve of the car a bit as I get used to how it acts on the strip,and from time to time the street.Speaking of stiff sidewall slicks, could anyone lead me in the direction of a set that will fit 9c1 wheels? Also, could you guys glean any starting line techniques you use in the box to keep the trans happy? Thanks you guys -Alex
 
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