32 replies to this topic

[Steve Scheifler]

Curious to hear what people assume/believe about fixing the common issue with cracks in the stock NA header, especially in the area of existing welds.

Is it allowed under the general repairs rule so long as you don't do any grinding inside the tubes, or is it a no-touch item? My memory of 4-5 years back is that no repairs to the tubes and welds were allowed, but certainly no such rule is spelled out.

Are you fixing them? Have you found that an external-only fix is pointless because it just fails again?

Related question, why not a rule that lets us clean up the ugly ones but explicitly excludes any change to tube diameter, length, configuration, etc? Is there really enough potential for abuse that we would be any worse off than we are now, trying to find a decent 25 year old fragile part that isn't cracked? Time to call this a no-brainer.

By the way, out of frustration I once paid the ridiculous price for a new one from Mazda, and it clearly had grinding marks inside where the sloppiest welds were cleaned up, rendering it non-compliant.

[38bfast]

Asking for the ability to do a repair and or clean up the variance on the collectors sounds very reasonable to me. On both the header and the down pipe. For the 1.6 and the 1.8. Alow a max I.D. and the ability to clean up the inside welds. Then you would not have to search for the holy grail exhaust manifold.

[ner88]

most often they crack because the exhaust mount on the tranmission has been left off.

dont know how you could weld the collectors in the middle where they all come together.

As to cleaning up the exhaust manifold ports, it would also require welding from the outside.

It would be much cheaper to allow an aftermarket header, EBay around $100.

The aftermarket header wont solve the parity issues as it offers very little performance gains.

[Steve Scheifler]

Well, we can debate new parts forever but that will require testing and a lengthy process. What I'm looking for right now are simple and "safe" trhings hat can still be approved for next season. Sadly, it appears that very little productive effort has been put into that during the three year lockdown so now we are at the deadline and will go yet another year without changes.

[Alberto]

I've just had a local welder fix them.  They seem to weld from the outside.  Not sure how you would weld them from the inside but I don't weld so....

[Steve Scheifler]

So nobody thinks a repair would make them non-compliant?

[Kyle Freiheit]

Non compliant but weenie protest. When is the last time a 1.6 had to pull off a manifold when running an SCCA race? 

 

Kyle

[38bfast]

Kyle illegal is ilegal. We have put many cracked manifolds in the dumpster. If you want to take the gamble that's up to you.

[Kyle Freiheit]

I am not pointing fingers Ralph. I have 2 cracked headers sitting on the shelf. Just saying this is club racing, lets use a little bit of common sense. 

 

Kyle

[Steve Scheifler]

No, let's change the rule to allow it without opening the door to significant other shenanigans. Combine it with an allowance to clean up ugly factory welds and things get closer and cheaper.

[B(Kuch)Kucera45]

I hope people are writing letters to the board about this or nothing will be done. I have seen plenty of 1.6 manifolds out there that are welded on the OD and there is no performance gain at all from doing so. So it should be easy to get this to pass as long as people summit a letter to the board.

[Ron Alan]

No, let's change the rule to allow it without opening the door to significant of shenanigans. Combine it with an allowance to clean up ugly factory welds and things get closer and cheaper.

For the life of me I have never understood why internal welds that restrict the flow by narrowing the pipe size  have to remain "as is" from the factory?? I pulled out a brand new 1.8 exhaust manifold  awhile back from Mazda that I had sitting on the shelf(maybe 4 years old). The welds are so overkill, each hole (4 at head and 1 at downpipe)are up to .250 less in diamater than the pipe size! I had an OEM 20 year old unit that was better but not perfect. So I took these and flowed them for fun. I forget the number we used on the volume of air(sucked into the single hole) but i remember it being just more than the amount of air a 1.8 can move at 7000rpm. The difference was close to 10%!! 305 cfm to 330 cfm.  

 

Why we should have to cherry pick through a pile of manifolds and downpipes to find ones that have welds no larger than the inside pipe size just seems silly. Kind of like castings and core shift...we remedied this for the most part...or did we 

 

The other irony as someone mentioned earler is the new manifold I have has grind marks in the welds. Not much but noticable...kind of like they were knocking off the real ugly parts(monday morning hangover welds!)

[38bfast]

Knocking down the welds to a max I.D. could be accomplished with a hand file. Seems like a easy fix to me. But then here I go thinking black and white again.

If I was the appointed tech Natzi this would be one item I would be randomly checking for compliance. External welds and internal modifications to down pipes and manifolds.

Although now the window may have been closed to get it in the 2015 rules. But a great opertunity to get it moving for 2016.

[chris haldeman]

You guys are kidding right??? Heads dq'd at runoffs for very very small deburing but you same people who called all those heads and drivers and builder cheaters now want too be able too grind welds on headers legal? You claim your reasoning too be so you don't need too find a cherry part?? Wtf do you think is happening with the heads?? If there was such a huge gain why would anybody sell it??? Please please tell me

[Steve Scheifler]

The difference is, we are asking for clarification of the current rules with regard to repairs, and ASKING for an explicit rule allowing cleanup of a rapidly dwindling supply of old parts, and avoid getting tossed for using one with grind marks from the factory.

If you don't see the difference, then it is little surprise that we ended up where we are today on heads, thank you very f'ing much!

[wheel]

"very very small deburing"  

Not even close to the truth.

[James York]

Steve,

 

I suspect the point may have been if you allow it to knock off the globs and such, you will have someone take it too far "into the grey".  Just another repeat of the head story.

 

Whether its right or wrong, smart or dumb to allow, I am not debating.  I just guess the point is that if allowed, some knee jerk reaction could happen when someone goes too far with it done the road.  And then of course, how would you measure this allowance?

[James York]

"very very small deburing"  

Not even close to the truth.

Perhaps the SCCA would like to enlighten the population with pics so we can see?  This seems to be a debated point repeatably.

[Brandon]

Jim,

I anticipate wheel either not being permitted nor willing to provide any further illumination on that particular subject.  I too have been informed off-hand that there was a wide-ranging variability of modifications to the STR of non-compliant heads - from merely deburring to outright "porting/smoothing" into the intake throat.  So the quote he used and responded to is appropriate vis a vis my own understanding (without pictures or further details outside of my trust & consideration of the source(s)).

 

Some modifications were so far BEYOND the referenced quote that even attempting to call it a 'gray area' makes it more like a cruel joke on the English language...

I hope that clarifies things for folks on the Runoffs head issues...

 

Now, regarding any current "repairs" on parts - as there is nothing specifically noted in the FSM for repair of a cracked header/manifold, I would suspect this would/could fall under the portion of the SM rules regarding "other repairs not specifically outlined" (if my memory is correct).  

 

That's just my $.02 in this case...

 

/rant

If I had one nit to pick about the SCCA it's this: the lack of forthcoming of data regarding violations (irrespective of this SM one).  Is it an effort to keep folks from further investigation on the potentially exploitable condition/variable?  Is it to save face on the aspect of 9 competitors being "DQ'ed" in this instance?

 

As others have noted, having pictures to reference, in terms of extremes in this case, would be a significant boon to builders and competitors.  For reviewing particular procedures (for the builders) and current status of parts (competitors) it would be immensely helpful to determining whether something could be considered compliant vs. not should a tech inspection be performed.

 

/rant

[ner88]

I have cleaned up a 1.6 exhaust manifold and tested it.

There is very little to be gained, in fact not even measurable.