825 replies to this topic

[Dave D.]

"I would remove every wire that has anything to do with an allowed removable system. That would be air bag, cruise control, A/C, stereo and anything else I can find. That takes about a day to accomplish. Saves about 10 pounds, most of it high, front end weight."

 

No way that would amount to 10 pounds,no way at all.................Have done it before and it weighed MAYBE 1.5 to 2 pounds. We're talking about 18 and 20ga wire.......angle hair, not battery cable.

 

I stand corrected.I got back to the shop and weighed the box of wire I still have from that car and it weighed 6.1 lbs. Now that is also before I added wire for the radio, data acc sensors, fan switches,and cool suit, so my net loss is negligible. The weight is also spread out over the entire car, not just high. I can honestly say I did not do this for any performance advantage, only making my life easier and routing the wires cleanly.

[dstevens]

Wheeler has built more SMs than many see in a run group at a regional race.  He knows what he's talking about.

 

In no particular order...

 

Reading the GCR.  It's a competitors responsibility to know the rules.  It's clunky, seemingly contradictory and a laborious read.  There is still stuff in it you need to know.  Printing it?  I print a few things, like the schematics or specific parts of the FSM that I happen to be wrenching at the time but not the GCR.  Our good friends in the state of Glenda will sell you one.  If it comes time to file a protest you'll absolutely want a GCR with more than just your class.

 

Six pounds is six pounds.  If you are over or near weight that could be six pounds of fuel.  Or a cool suit.  If you were 30 pounds over that's 20% of the weight right there.  It is high by a couple of feet.  One of the details of car building that separates the men from the boys is the attention to detail and stripping every last ounce of weight or being able to distribute it to be as low as possible.  At the pointy end of SM the difference is 100ths or 1000ths in some cases.  If the car isn't over weight that sprung six pounds is better spent on the floor of your car in lead or redistributed for that last bit of balance.  It's all about the detail.  And this is one of them.  Most racers won't be able to capitalize on that.  They aren't that good, or have poor prep and setup and are just there for the fun if it or most likely, all of the above.   Like I was.  It's a game of inches, each little bit helps.

 

I agree the rule doesn't make sense in a class where the performance dims are being teched to the .001 and the money involved now to run up front is outside the comfort zone for most hobby racers. Wiring should be open.  Things like the dash, heater core, blower, smog should be able to be removed.  The class started as a street car that was easily adaptable to the track.  Now for the most part it's a street car base that gets a tub up build to a race car.  But, the rules are the rules for everyone even those that are bent to cheat enterprising engineers that find a what to exploit any loophole.  It's easily the best thing going in club sports car racing and arguably one of the best, of not the best things in hobby racing in general in the US.

[Dave D.]

Understood. It's not like I am trying to get the rules so relaxed we end up with Prod racers. I still think we should never be allowed to remove the dash, heater and blower. The smog stuff? They don't bother me enough as messy wiring. However I still feel that this is an issue way less important than drive train legality.

[speedengineer]

Just realized that the camera I use for in-car footage also does time-lapse photos.  Wish I would of realized that before I started taking the car apart!  Still, lots of build time left so I think I'll play around with taking some time lapse.  Haven't done this before, but maybe by the end it'll make for an interesting video

[speedengineer]

Oh, also now taking suggestions for a theme song/anthem for the time lapse build video.  Needs to be some combination of exciting/intense/inspirational/building up to a climax, etc, etc.

 

So far, thinking excerpts from one of the following:

• Ted Nugent, either Fred Bear or Stranglehold
• Requiem for a Dream - https://www.youtube....h?v=i5Kwf_nNmGI

What else can you think of?

[wreckerboy]

http://youtu.be/ZnHmskwqCCQ

[speedengineer]

...http://youtu.be/ZnHmskwqCCQ

 

Lol!  That's the music I'll choose if my car ends up being a turd and I wasted 300 hours of my life building it 

[Steve Scheifler]

If in my opinion, if the rules allowed me to gut the wire harness, I would remove every wire that has anything to do with an allowed removable system. That would be air bag, cruise control, A/C, stereo and anything else I can find. That takes about a day to accomplish. Saves about 10 pounds, most of it high, front end weight. I think that would be a performance advantage. BUT, in my opinion it is not legal. Therefore I do not do it.

If in your opinion, it is legal. DO IT. If you have strange electrical gremlins, my first response would be to get another unmodified harness. If something happens in tech, then it is your opinion versus the tech guy. Good Luck

Dave

I'm trying to understand. The rule for the radio and antenna make no mention of the antenna cable, but I consider that to be part of the radio "system" and assume you do too. Meanwhile the only reference to the wiring harness very explicitly refers to the engine electrical harness and even includes the ECU in the same sentence making it very clear that the rule is to prevent tampering with signals to it. Speaker wires absolutely are not part of the engine electrical harness, but they are just as much part of the radio system as the antenna cable.

Note that nothing I have said implies that the rules allow you to gut all manner of other wiring just because it isn't part of the engine harness, but if it relates to a system which can be removed then it is fair game.

[speedengineer]

...http://youtu.be/ZnHmskwqCCQ[/video]

 

So my thought process went like this:

1)  I have all these photos of time lapse engine measurements that I took today

2)  I should make a test video to ensure that taking the footage is worthwhile and I don't take 200 hours of footage for no reason

3)  I made the test video.  I think it needs music

4)  Well crap, might as well use the audio that Rob posted

 

Now who's laughing?    Actually, I'm probably going to regret posting this...

 

 

Good news is everything I measured and weight checked out.  Pistons are close, within 3 grams, though they still have carbon and oil on them.  Rods are fat compared to other rods I have, 551g.  Crank end play was 0.005". Need to do a more thorough cam profile inspection at the time of cyl head assembly, but from basic micrometer measurements it appears to be in spec.  Oil rings on the pistons were rather gunked up with carbon.  Cylinder head has 0.025" of meat on it still for shaving.

 

I've had difficulty getting good crank runout measurements in the past.  Dial indicator shows a 'phantom' runout that isn't there if you apply very light pressure to the indicator shaft.  I don't have those plastic v-blocks like the pro's probably use.  Anyone have any other ideas for how to measure crank runout other than setting the crank in the block on two bearing shells?

[Danny Steyn]

Jason - this is turning out to be an enjoyable and informative thread - keep it up

[Kyle Freiheit]

I have always measured it the same way as you did. That said, making v blocks are super simple. If you don't have a local retail plastics place to buy PVC or HDPE you can cut up a cheap cutting board.

 

Kyle

[Bench Racer]

Agreed!

Now read the part about the inner structural panel ;not the beam/brace) and tell me exactly how much of that can be removed under what conditions.

Took me a bit, was looking for door part names, found none. When looking at a 1990 door the door basically has two main parts. Lets call the first part the door structural part which includes the inner panel including the bottom and both ends, one piece. At the upper inner panel closest to the window there is a support piece added to each side of the inner panel therefore through that length it's three layers thick. The second part is the outside door skin which is attached to the door structural part. The inner door structural panel may be modified, but not removed only if the door bars extend into the door cavity. My understanding is modify (the word modify is wide open from bend the inner structural out of the way to cut and remove the metal) for the door bars to extend into the door cavity. Remove inner structural panel X larger than enough for the door bars is a personal decision a person may need to explain to a tech shed person some day. I've never viewed door bars high enough in the door to justify cutting out the three layer section of the inner panel structure near the window. IIRC when I was building an Miata F prod car there was something like nine pounds of inner structural panel including the three layer area taken out of each door.

 

Steve, did I hit the point you may have been aiming towards? 

[speedengineer]

Two questions:

 

1)  Is there an easy way to clean the carbon off of the piston tops and especially from all of the ring grooves? 

2)  When ordering new pistons from Mazda, do they come loaded with rings, or do you need to buy a ring set separately?

 

Basically, last time I cleaned oem pistons, I used oven cleaner.  This cut through the carbon very efficiently, but it also removed the shiny coating on the pistons bringing them back to dull aluminum.  If I can't find a fast and effective way to clean the pistons, I may just order new ones assuming they come with rings.  The cost of the pistons over a ring set is marginal and would save the headache of doing the cleaning.  Of course if the new pistons don't come with rings, then the cost factor makes it worthwhile to just perform the cleaning.

[Jim Drago]

Two questions:
 
1)  Is there an easy way to clean the carbon off of the piston tops and especially from all of the ring grooves? 
2)  When ordering new pistons from Mazda, do they come loaded with rings, or do you need to buy a ring set separately?
 
Basically, last time I cleaned oem pistons, I used oven cleaner.  This cut through the carbon very efficiently, but it also removed the shiny coating on the pistons bringing them back to dull aluminum.  If I can't find a fast and effective way to clean the pistons, I may just order new ones assuming they come with rings.  The cost of the pistons over a ring set is marginal and would save the headache of doing the cleaning.  Of course if the new pistons don't come with rings, then the cost factor makes it worthwhile to just perform the cleaning.

Soak them over night in carb cleaner and they will come out looking new.
pistons DO NOT come with rings

[speedengineer]

Soak them over night in carb cleaner and they will come out looking new.
pistons DO NOT come with rings

Thanks Jim!

[dstevens]

The Berryman carb cleaner works great as does Seafoam.

 

cleaning pistons by Dave Stevens, on Flickr

[FTodaro]

 

 

 

2)  When ordering new pistons from Mazda, do they come loaded with rings, or do you need to buy a ring set separately?

 

 

And those Mazda Rings are not cheap. More expensive that after market rings, but if you want to be legal better use the Mazda, i will say that when i built a street motor myself, it was a mistake using non mazda rings.

[speedengineer]

The Berryman carb cleaner works great as does Seafoam.

 

cleaning pistons by Dave Stevens, on Flickr

 

Not bad!!  I'll have to see what I can get for cheaper.  A 3/4 gallon of carb cleaner is $19.  Will need to price out a couple cans of seafoam.  Need to be thrifty...this is a sub $15k build after all 

 

And those Mazda Rings are not cheap. More expensive that after market rings, but if you want to be legal better use the Mazda, i will say that when i built a street motor myself, it was a mistake using non mazda rings.

I've got three sets of OEM used ring sets now.  Too bad I think it'd be a mistake to reuse them.  I think the last set of OEM rings I bought was about $120.

 

I find it funny, for example, how standard size OEM bearings are $$$ and oversize bearings are only $.  Supply vs demand, I suppose.  My main bearings look spotless, I might reuse them.  Rod bearings are pretty decent too but slight witness marks are visible.  I think aftermarket bearings are legal, right?  I need to check the rules again.

[speedengineer]

Tonight I opened early Christmas presents from Mazda, assembled a new tool, and cut out some sheet metal where the cage forwards hoops will pass through.

 

 

First, the new toy.  Should have bought one of these years ago.  It is going to come in real handy with all the fab work in my near future.  I'm pretty sure I now own more harbor freight tools than non harbor freight tools.  lol.

 

 

Presents from Mazda Motorsports.  Thanks for the free shipping!  Suspension kit, motor mounts, offset bushings, AC delete duct.

 

 

As for working on the car, I started doing a little more pre-cage prep.  The forward hoops will follow the A-pillars, and then drop down vertically just in front of the door opening.  There were spot-welded in sheet metal pieces that were in the way and needed to come out. 

 

 

[dstevens]

Technically you can't use anything you didn't get from Mazda on an internal.  My parts guy at the time has since retired but I was able to get rings, bearings and a few other things for about 20% of what Mazda wanted even with the MSM discount.  On the bearings and rings what was stamped on them was what was stamped on what I took out.  The rings were branded Mahle and the bearings were branded Clevite IIRC.

 

The Berryman is expensive but lasts a long time.  The big can has a tray inside so you can soak the parts.   We used it a bunch to clean Holly and Quadrajet parts in circle track.  I use Berrymans for solvent parts washing these days.  Consumables are expensive and for the good stuff there'e really no way around it.  Seafoam is around $8-10 a can.  The intended use for Seafoam is fuel system cleaner.

 

The HF combo sander looks like the 6 x 9.  That's the best one they've got though it's more suited for wood due to torque.  Don't be too aggressive on the stock or you'll bog it.  For the price it's pretty good, it should work well for you.   I'd get some real media on it.    The belts Lehigh Valley Abrasives may have. We've got a great local industrial hardware supply company where I get most of my abrasives.  You can also try the usual suspects, Grainger, Enco, MSC.  Roark in Orange CA is pretty good too.   Abrasives are expensive too.  You should budget a few hundred in fab consumables not counting break in fluids for the car.   I count drills, cutters, hole saws as well, anything that wears and is disposable.   I've had a couple of the HF 12" sanders in the last several years.  I'm pleased with them.  That's one tool we use quite a bit for the printer parts fab.