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Author Topic: Build Guide Car, Holes
JIM DANIELS
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Working on and documenting the build guide car.

Right now I'm selecting and tweaking peripherals which brings me to this crossroad.

The rules state:

quote:
All air entering the intake tract shall pass through the fuel injection air inlet.
To me that clearly means that cars with a restrictor plate should have all the intake orifices caped, blocked and/or externally vented less allowing air to bypass the RP. The inlet, as stated in the passage above, should be the sole entry and control point. Makes sense to me, what use is a RP if there are other openings that can be tweaked and cannot be teched?

However, the rule is not being enforced on any level as written. I suspect that under this rule, at any given event, a protest regarding the intake orifices would be well founded. Not being enforced and under the assumption that more than OEM can be achieved, makes this a hole and gray area.

From my perspective the rule needs to be clarified and enforced in a way that requires ALL air pass through the RP or be vented externally. My opinion is simply based on one notion, if we are going to use plates to control power via air flow we have to know the plate is operating in the same condition car to car (see how the WC cars are capped off).

From my builders perspective, an easily manipulated tweak area for adding air to a restricted air car.

I've had my fill for 2010 sending letters. I would rather see what the other owners think. Do I build the car with the orifices closed or open?

[group hug]

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You can leave them open if you want the car will run like crap.

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Keith in WA Verified Driver Made Donation to Website
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Interesting question. On a 1.8 the brass EGR hose sucks hot exhaust into the intake manifold. Plugging that hole would mean lower temp air reaching the combustion chamber. The rules don't say you can disable it but they do say all air must pass through the RP so I guess it is a loop hole.

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George Munson Verified Driver
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I would like more details.

Drago Verified Driver Made Donation to Website Series Champ
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The EGR is not open in hard acceleration. So hot air should never enter the intake through EGR during race conditions, well unless you spend a lot of time at idle [Big Grin]

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cintibob
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I heard one time about nascar guys bypassing the R.P. somehow to get more power I would think with a afm any air not going thru it would cause problems. I think making more holes in the bottom of the air box might not even help. Without some sort of vortex plate or addition to smooth air thru restrictor plate as jegs has that fits ontop of carbs I can not see any advantage to open lines behind the RP. That also is a attempt to bypass a rule to limit air entering thru the throttle body. Why not then alter the RP and recolor it to look unaltered? Since the tech guys just look at the color of the plate with maybe the exception of the runoffs. Jim your assumption I think is correct build it closed or vented as new.

Willie the Tard Verified Driver
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I would think that the PCV and brake booster would be the most logical ways to get non-RP air behind the RP. If it is like the 1.6 the PCV air would still go through the MAF. The PCV "air" would be diluted with blow by gases. And I do not know how to modify the brake booster to supply extra air and still work as a booster but I guess someone smart that me (and most are) could figure it out

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William Keeling a.k.a. Willie the Tard

JIM DANIELS
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"non-recirculating air" or something like that needs to be in there for what must pass through the inlet.

Drago, can the EGR be rigged to be open at WOT then draw fresh air? Would it make more power, how to tech it?

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Daniels
Can a fire bottle be filled with nitrous? [Wink] Anything "can" be done...

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JIM DANIELS
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NEW QUESTION

quote:
p. Electrical Equipment
1. The ECU and engine electrical harness must be as supplied
by Mazda. No modifications are permitted. The ECU maps
and inputs must not be modified.

Jimmy, Mike, Dave,

I assume that we can still remove the portions of the harness that feed items that are allowed to be removed? ABS, electric mirrors, radio, air bags etc?

I have no idea what you are talking about on the NoS [Wink]

Thanks!

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quote:
Originally posted by Drago:
Daniels
Can a fire bottle be filled with nitrous? [Wink] Anything "can" be done...

Now that is a good idea -- anybody know what kind of volumn I will need for a 45 minute race?

--------------------
William Keeling a.k.a. Willie the Tard

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Does an NB have an IAC valve? If it does, that's technically in violation of this rule since it bypasses the throttle.

-Kyle

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That wording was put in to specificly keep people from removing the wires for unused optional equipment.

JD, you know the rule: If it doesn't say you can, you can not.

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JIM DANIELS
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quote:
Originally posted by davew:
That wording was put in to specificly keep people from removing the wires for unused optional equipment.

JD, you know the rule: If it doesn't say you can, you can not.

I'm learning [Smile]

Gotcha, thanks!

Z-MAN Verified Driver
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Oh come on people haven't you all learned yet that JD only asks these questions in public forums when he knows there is a way to make it happen [yep]


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quote:
Originally posted by Willie the Tard:
quote:
Originally posted by Drago:
Daniels
Can a fire bottle be filled with nitrous? [Wink] Anything "can" be done...

Now that is a good idea -- anybody know what kind of volumn I will need for a 45 minute race?
Here you go William, though might stand out just a little.
Large NOS tank

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Blix Verified Driver
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quote:
Originally posted by davew:
That wording was put in to specificly keep people from removing the wires for unused optional equipment.

JD, you know the rule: If it doesn't say you can, you can not.

So what you're saying is that all of the people out there who removed the air bag wiring, radio wiring (including the antenna wire), or repaired a damaged wiring harness with a shorter than stock, or smaller than stock piece of wire either have to put the wires back or buy a new harness? have you seen the cost of those things?!?

What about all the people who bought a used car that had an aftermarket radio, alarm, etc. installed? They're all non-compliant as well.

Thats a lot of people I believe, a very lot of people...

E

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Keith in WA Verified Driver Made Donation to Website
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Note the rule though...The ECU and engine electrical harness must be as supplied by Mazda. No modifications are permitted.

Some stuff can explicitly be removed like the air bag system which has a separate harness that plugs into the main harness and the harness and sensors are part of the system. Other stuff, has a secondary harness that plugs into the main harness like the radio, antenna and electric windows. I'm reading it like you can't alter the main harness to do things like remove the AC or PS leads.

For repairs...All chassis/structural/electrical repairs, if performed, shall be in concurrence with factory procedures, specifications, and dimensions .

Seems to me, if you have to fix a broken wire (who hasn't), perfectly legal. I don't see wire lengths or guages in the shop manualbut if you put a little thin wire or coil a really long wire somewhere that acts as an inline resistor, not legal.

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Fair enough, good response. I wasnt thinking that all the way thru...correct me if i'm wrong (again), but the ECU doesnt plug right into the engine harness. I'd call the engine harness the thing that has, for example, the connections to the injectors. The ECU plugs into the main harness, that a bunch of other things plug into. SOOOOO...I feel like that should be clarified a bit...something about engine, main harness and ecu, allowed to remove wires used only by airbag system, radio, door buzzer, overhead light....i dunno, its a rats nest (the rule AND my wiring harness...)

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quote:
Originally posted by Blix:
Fair enough, good response. I wasnt thinking that all the way thru...correct me if i'm wrong (again), but the ECU doesnt plug right into the engine harness. I'd call the engine harness the thing that has, for example, the connections to the injectors. The ECU plugs into the main harness, that a bunch of other things plug into. SOOOOO...I feel like that should be clarified a bit...something about engine, main harness and ecu, allowed to remove wires used only by airbag system, radio, door buzzer, overhead light....i dunno, its a rats nest (the rule AND my wiring harness...)

As per the FSM and part list the engine harness is the one on the PPF, no such thing as an ECU harness ECU wiring is part of the "front harness". The harness on the engine is called the "injector harness". The air bag "harness" is part of the front harness. It is mostly in separate blue sheathing but is does not unplug from the front harness (2 wires must be cut). The Canada front harness does not have the airbag stuff and would be legal. Most of the radio wires are part of the "dash harness" that appears to be open. The radio antenna wire is not part of any harness. As I only have/working 1.6 cars all this only known to be true for it.

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William Keeling a.k.a. Willie the Tard

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quote:
Originally posted by Willie the Tard:
quote:
Originally posted by Drago:
Daniels
Can a fire bottle be filled with nitrous? [Wink] Anything "can" be done...

Now that is a good idea -- anybody know what kind of volumn I will need for a 45 minute race?
I need more input for this calculation. Where did you qualify, how many straights on the track in question, how many HP is your system set up for.....but based on what I have observed a 5 lb bottle should get you third place.

--------------------
Michael Ross

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quote:
Originally posted by Keith in WA:
Interesting question. On a 1.8 the brass EGR hose sucks hot exhaust into the intake manifold. Plugging that hole would mean lower temp air reaching the combustion chamber. The rules don't say you can disable it but they do say all air must pass through the RP so I guess it is a loop hole.

maybe i mis read your post, but EGR "air" has already gone throught the plate...

sam

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pat.ross
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Willie,

You should only use the Nitrous Oxide when you want to pass. That way it will last longer.

Pat

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quote:
Originally posted by springfielddyno:
quote:
Originally posted by Keith in WA:
Interesting question. On a 1.8 the brass EGR hose sucks hot exhaust into the intake manifold. Plugging that hole would mean lower temp air reaching the combustion chamber. The rules don't say you can disable it but they do say all air must pass through the RP so I guess it is a loop hole.

maybe i mis read your post, but EGR "air" has already gone throught the plate...

sam

I'm pretty ignorant about how the whole EGR system works I guess. I was thinking the EGR tube just dumps exhaust into the back of the intake manifold and don't know much about how the valve works. Been a while since I looked at it and not the best memory some days. [Smile]

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JIM DANIELS
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quote:
Originally posted by Keith in WA:
Note the rule though...The ECU and engine electrical harness must be as supplied by Mazda. No modifications are permitted.

Some stuff can explicitly be removed like the air bag system which has a separate harness that plugs into the main harness and the harness and sensors are part of the system. Other stuff, has a secondary harness that plugs into the main harness like the radio, antenna and electric windows. I'm reading it like you can't alter the main harness to do things like remove the AC or PS leads.

For repairs...All chassis/structural/electrical repairs, if performed, shall be in concurrence with factory procedures, specifications, and dimensions .

Seems to me, if you have to fix a broken wire (who hasn't), perfectly legal. I don't see wire lengths or guages in the shop manualbut if you put a little thin wire or coil a really long wire somewhere that acts as an inline resistor, not legal.

Was not always the rule, just was no bitching about it changing, see "polished" [Wink]

   

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