140 replies to this topic

[pfrichardson]

...are posted:

http://www.scca.com/.../cars-and-rules

[Bench Racer]

SM

 

1. #17222 (Eric Matoy) 1.6 L SM Intake Air Temperature Thank you for your request. 

 

The CRB thanks the below authors for their feedback on this topic:

David Dewhurst (17432, 17593, and 17727), Dave Wheeler (17548 and 17690), Charles Singletary (17557), Michael Babcock (17568), Jerry Rigoli (17571), Justin Casey (17596), Dennis Mathias (17689), Taylor Ferranti (17691), Tom Scheifler (17693), Steve Scheifler (17693), Jim Morris (17694 and 17734), Jim Drago (17695), Will Schrader (17697), Gary Bockman( 17702), Andrew Devoto (17706), Tom Fowler (17716), Callum Hay (17720), Charles Mathes (17722), Dennis Mathias (17728), Mark McCallister (17729), Patrick McFall, Sr. (17736), Mike Higgins (17739), Alan Cross (17742), Manny Platis (17742), Richard Powers (17751), Geoff Cochran (17787), Andrew Cremins (17948), Tom Fowler (17967). 

 

In order to establish parity for the 1.6L engines, the CRB recommends: 

 

Change 9.1.7.C.1.m.1:1. The exhaust manifold must be Mazda OEM, without any material added or removed. No coatings are permitted on the exterior or interior of the manifold. Heat wraps may not be used. 1.6L (1990-1993): The exhaust manifold internal factory welds may be ground from the interior of the OEM exhaust manifold up to 1" from the mounting surfaces of the cylinder head and the collector.  A bead of weld or braze may be added to the outside of the exhaust manifold inlet and outlet mounting flanges for the purposes of repair only. No coatings are permitted on the exterior or interior of the manifold. Heat wraps may not be used. 
All other years: The exhaust manifold must be Mazda OEM, without any material added or removed. No coatings are permitted on the exterior or interior of the manifold. Heat wraps may not be used. 

 

Change 9.1.7.C.1.k.1.a.:a. 1.6L (1990-1993) cars may replace the stock air box with a cone style air filter assembly. The air filter element is unrestricted. No ducting or baffling of air to the air filter is permitted., however, the forward-facing driver's side turn signal indicator may be removed.  The stock plastic air tubes between the AFM and the throttle body may be covered or wrapped. 

 

2. #17569 (Cameron Conover) Allow Removal of EVAP Components Add 9.1.7.C.1.l.2: 2. Fuel filler tube venting may be defeated (loop or block vent lines in trunk). 

 

3. #17931 (Ralph Provitz) Shifter and Linkage to Be OE Add 9.1.7.C.2.f.: f. Updating or backdating of transmissions (inclusive of shifters) from 90-05 is permitted; OE shifters must be retained.

[Dave D.]

Is a shift knob separate or included in "shifter"??

[38bfast]

The shift knob is open. 

[38bfast]

Spec Miata

1. #17818 (Ralph Provitz) Throttle Body/Restrictor Gaskets
In GCR Section 9.1.7.C.1.k.1.d., add the following language:
"....and must not be modified. An OE (or equivalent) gasket shall be used on both sides of the restrictor plate."

 

 

2. #17821 (Jim Drago) Compression and Carbon
In GCR section 9.1.7.C.1., remove section j. (compression ratio table) and re-letter the following sections.

In SM spec line, add "(without carbon)" to the Bore x Stroke column. 

[B(Kuch)Kucera45]

Oh snap the 1.6 just became an over dog overnight !

[Bench Racer]

 

Spec Miata

 

2. #17821 (Jim Drago) Compression and Carbon
In GCR section 9.1.7.C.1., remove section j. (compression ratio table) and re-letter the following sections.

In SM spec line, add "(without carbon)" to the Bore x Stroke column. 

 

Discussion:

 

How long does it take to build up 1 CC (= .062 inch cubed) of carbon?

 

This seems to be advantage to a head with carbon build up. A podium position could be gained with an over maximum compression ratio engine because of carbon build up, clean out the carbon and compression ratio is within allowed. Hmmmm..........................

[Jim Drago]

Discussion:
 
How long does it take to build up 1 CC (= .062 inch cubed) of carbon?
 
This seems to be advantage to a head with carbon build up. A podium position could be gained with an over maximum compression ratio engine because of carbon build up, clean out the carbon and compression ratio is within allowed. Hmmmm..........................

Maybe you should try it..

[Todd Lamb]

Pop quiz: Is "without carbon" a new rule?

[Bench Racer]

Maybe you should try it..

 

As an engine builder and author of the rule maybe you should support your request openly.

 

During past SM compression ratio issues when the head came off for CC and calculation was the carbon removed?

[davew]

If it does not say you can have carbon, you can not.

[Steve Scheifler]

Thanks for the efforts to this point.

So these are the CRB recommendations still open for feedback prior to board approval, correct? And I believe wording can still be tweak or even minor changes made.

I would like to know why the turn indicator delete recommendation did not include removal of that side headlamp bulb, the location of which likely limits the effectiveness of the new rule. Was it discussed? If yes, exactly what were the arguments against?

[Jim Drago]

As an engine builder and author of the rule maybe you should support your request openly.
 
During past SM compression ratio issues when the head came off for CC and calculation was the carbon removed?

Read the rule.. it has always said without carbon.. At the Runoffs the CCC stated ONLY FV was allowed to remove carbon, I wanted that cleared up. All engines are built very close to the max with new parts( no carbon). A competitor if over should be allowed to remove any carbon present. If over it is FAR more likely that there is an error in the measuring process far greater than any amount of carbon present. How many engines that are pulled apart at the Runoffs do you think have much if any carbon?
This is another one of those times where you are looking for something that doesnt exist. But what else do you have to do.

[38bfast]

Thanks for the efforts to this point.
So these are the CRB recommendations still open for feedback prior to board approval, correct? And I believe wording can still be tweak or even minor changes made.
I would like to know why the turn indicator delete recommendation did not include removal of that side headlamp bulb, the location of which likely limits the effectiveness of the new rule. Was it discussed? If yes, exactly what were the arguments against?

Steve all the testing showed that with the headlight in the performance gain was substantial.

[Steve Scheifler]

OK, but was it tested without? Was the point discussed? If so was it rejected simply because the SMAC decided that the results with it in were "enough"?

[Bench Racer]

Dave, following your logic, the engine would be illegal the moment the carbon was viewed, correct. 

 

 

 

 

 

[Jason J Ball]

Playing devils' advocate here, what's to prevent us from grinding down the weld until a crack develops and then just throwing a weld on the outside. Effectively removing 99% of the interior weld. 

 

I think it needs a little work on the wording to prevent ^

 

Also add specific language to describe how the 1" restriction is going to be measured  1" "depth" from face of mating flange (Inlet/Collector). And explicitly restrict or allow removal of material from the flanges. Keeping in mind the tooling that will be used to remove this material, some will use a bit on a die grinder, others may use a drill and a grinding stone bit. Meaning you have limited ability to control where the removal starts and stops as to the flanges.

[chris haldeman]

I know this..... Every 1.6 header I prep for customers will be cracked on every tube and require weld on the outside. The weld around the outside will be required in my opinion since we are removing the only weld holding them together. Not a rule problem and I'm sure this was the plan of the rules makers all along. Also too address the flange being ground there is not enough room depth wise too be a benefit. Free tip for all 1.6 guys.... If the header gasket isn't held properly during assemble it will fall down and block the exhaust port costing you power

[Jim Drago]

Spec Miata

#17818 (Ralph Provitz) Throttle Body/Restrictor Gaskets
In GCR Section 9.1.7.C.1.k.1.d., add the following language:
"....and must not be modified. [/size][/font]An OE (or equivalent) gasket shall be used on both sides of the restrictor plate.[/size]"[/size]

I hate to say this and be critical.. But this is SOOOO stupid!
There does not need to be any gasket there as the plate acts as a gasket.. worst case require one between the plate and intake as to not by pass the restrict or. I have been stall tested at least twice with no gasket at all and it stalled immediately and collapsed the rubber hose they used instantly. We are adding a rule that doesn't need to be there and serves no purpose.

[Mike Collins]

I know this..... Every 1.6 header I prep for customers will be cracked on every tube and require weld on the outside. The weld around the outside will be required in my opinion since we are removing the only weld holding them together. Not a rule problem and I'm sure this was the plan of the rules makers all along. Also too address the flange being ground there is not enough room depth wise too be a benefit. Free tip for all 1.6 guys.... If the header gasket isn't held properly during assemble it will fall down and block the exhaust port costing you power

oh, so I'm not the only one that dresses an engine on the stand with it rotated so everything goes on perfect...