825 replies to this topic

[38bfast]

Jason good to see your not pushing the easy button and putting the cage behind the dash. Very smart choice.

[speedengineer]

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. 

 

I'm pretty happy with the 6x9 belt sander.  Sufficient quality for home use.  The belt speed feet per minute feels a bit slow though.  I used to work in a machine shop during high school, and besides typical machining jobs, we built belt sanders, primarily for the investment casting industry.  These things were legit.  We also had a couple smaller units for the shop and I remember belt speed being way faster, which means they obviously removed material that much faster.  Makes the machine louder though, this HF one is reasonably quite.  Definitely need some new abrasives for it, the ones that came with it seem to remove about as much abrasive from the belt as they do metal from your workpiece, haha. 

 

To anyone shopping Harbor Freight, HF has 25% off coupons valid until Sunday, and I think again on Jan 1st.  That made the belt sander only $164 plus tax. 

 

 

I'm certainly budgeting for consumables.  All the cage metal was only $324 total.  I've got another $350 budgeted for grinding, cutting, welding supplies, and paint.  Should be around $700 all together.

 

I looked up the GCR and NASA rules.  Looks like allow the use of non OEM engine bearings provided they are in the standard size range of the mazda service manual. 

2. Main and rod bearings must not be modified in any way.
OEM and non-OEM bearings must be used from within the
standard ranges as allowed in the Mazda factory service
manual.

[speedengineer]

Jason good to see your not pushing the easy button and putting the cage behind the dash. Very smart choice.

 

I cringe every time I see one of those cages! 

 

This new cage will be similar to my last cage, which I am very happy with.  (the one I posted photos of on page 4).  I do have a few improvements planned.  The new cage will add a roof bar, both for the extra safety in the event of a rollover and because I need a good place to put a helmet hook!  The passenger side door bars will be of a slightly different design, still an x-brace of sorts that comes out into the door.  However, rather than intersect the tubes at the center, the bars will each be once piece from the main hoop to the forward hoop.  It will be like nascar bars that only have one bend in them, and are brought together at the center. 

 

I may also modify how I did the drivers side door bars.  Anybody who has ever built a cage knows just how flexible 1.5x0.095 tubing is.  If a 4-foot tube was welded rigidly on one end, you could grab the free end and move it around significantly with very little force.  Nascar bars on the drivers side are parallel to each other, thus they do little for chassis stiffening.  Adding vertical supports between the bars doesn't help for stiffness as you are making rectangles, not triangles.  So, this year I plan to do the horizontal bars just like last time, but will probably install the supports between the bars in a truss configuration:  |\/\| 

 

I wish miatas had larger cockpits.  FIA bars would be nice to have, but there just doesn't seem to be enough room and still be able to egress the car effectively.

[Bench Racer]

Jason, quick note referencing copying SCCA SMCS and other required stuff from SCCA GCR one may obtain a hard copy from SCCA. Using the on-line version is a PITA.

 

Keep on having fun.

[speedengineer]

Jason, quick note referencing copying SCCA SMCS and other required stuff from SCCA GCR one may obtain a hard copy from SCCA. Using the on-line version is a PITA.

 

Keep on having fun.

 

But "ctrl-F" doesn't work on the hardcopy version!  Hardcopy could be handy while at the track though.

 

I think once the 2016 GCR is published, I'm going to make my own copy of the GCR that has all of the non-SM and not relevant pages removed.  Then resave to PDF.  It will be awesome.

[zigspeed10]

Nice work on the build! Keep the pics coming because I need all the help I can get for my build.

Saw your comment about the FIA bar and here is an example I found when researching Miata cages. I'm considering doing something similar.





Thanks

Dave

[speedengineer]

Nice work on the build! Keep the pics coming because I need all the help I can get for my build.

Saw your comment about the FIA bar and here is an example I found when researching Miata cages. I'm considering doing something similar.


Thanks

Dave

 

Hi Dave.  Thanks for the FIA bar ideas.  That looks pretty effective.  It also looks like a pain to install the dash.  Perhaps this would be a good application for a bolt-in FIA bar?  I'll have to do some thinking on it.  Keep me up to date with your build and let me know if you have any breakthroughs, I'll do the same!

 

I know you've been reading mazdaracers for a while now, but since you just officially made an account, welcome!  Congratulations, you are the 1,000 Dave here!  It gets confusing sometimes... 

[38bfast]

The good thing about SM is they are so light and just don't go that fast so the can not build the kinetic energy in a crash like the big heavy fast cars. Overall we have seen many wrecks and only a very few had issues with the cage not performing as well as hoped. That to me says a lot. I would guess that it has to be one of the safest classes to run.

[Bench Racer]

 

 

Jason, this is a comment referenced to a SM crash someplace in Texas. 38bfast's comment reminded me. A car was off track dead perpendicular to the track direction. Another car T boned the passengers door and about drove thru between the rocker panel and the lower side protection tube. If I were building a car today using the X side protection/structural tubes per the white car ^ I would install a horizontal tube as low as I could to the rocker panel. Maybe someone can search or knows where the pictures are.

 

Keep the info coming.

[Duncan]

Nice work on the build! Keep the pics coming because I need all the help I can get for my build.

Saw your comment about the FIA bar and here is an example I found when researching Miata cages. I'm considering doing something similar.





Thanks

Dave

 

That's my car.  The bars are completely unnoticeable when you're in the car, but you're correct in that getting the dash in was challenging.

 

I cut the dash in two pieces where the airbag cover snaps in.  I riveted two small pieces of aluminum underneath to help stitch the dash back together and with the airbag cover in place you have to look hard to notice it's two pieces.   This is a slightly modified MiataCage btw, done by Blaine Fabrication in California.  Changes were to line up the backstays with the roof bars, offset the roof diagonal for more space, and the FIA bars shown above.  

Duncan

[dstevens]

Alan Blaine does fantasic work.  I talked to him about doing a custom cage for me way back when but opted to do it myself.  He posted for a while at Corner Carvers.  There is a nine year old, 45 page cage design/build thread that is still active.  http://corner-carver...ead.php?t=27556

[speedengineer]

Well today I spent most of my time organizing the shop, putting the trailer away for the season, and other misc stuff.  I did have some time to work on the motor a bit:

-cleaned the carbon off of the combustion chambers

-cleaned one piston and reassembled with conrod

-began reassembling the bottom end in preparation for piston/block  CC'ing

 

 

Clean combustion chambers.  Measured all factory machining depth from bottom of valve seat, and all pass the spec. Deepest factory cut was on the exhaust side in cylinder 1, valve 1, at 9.5mm.  Factory intake side ranges from 5 to 8mm

 

 

Piston pin reassembly tip:  At room temperature, you would have to press/tap the wrist pin through the piston.  However, if you use a heat gun to warm the piston up to maybe 140-160 F the pin will slip right in.  Cake.

 

 

 

When I was at walmart the other day to pick up up carb cleaner, I saw these multipurpose lights for sale.  $6, has a spring clamp for easy positioning.  I had to buy one.  Also bought an LED bulb for the first time.  100 watt equivalent, but I swear it's brighter than a 100W incandescent.  Maybe it's just the color of the light that makes it seem brighter.  Either way, with the LED bulb, I won't have to worry about the bulb breaking if I drop the light, nor burning myself, and it uses less power - though the power thing is mute since it was a $12 bulb...

 

 

 

I took a trip to my friend Jeremiah's house the other day to pick up the tubing bender that he is lending me.  Thanks Jeremiah!  Anyway, as I was driving home, I spotted this piece of redneckery.  Couldn't not share this here 

[38bfast]

I took a trip to my friend Jeremiah's house the other day to pick up the tubing bender that he is lending me.  Thanks Jeremiah!  Anyway, as I was driving home, I spotted this piece of redneckery.  Couldn't not share this here 

What could possibly go wrong.

[wheel]

That's a stout looking limb.  I think it will be all right.

[Bench Racer]

Day job, OSHA inspector.

 

 

[Danica Davison]

we just built our 99 in the range between 15k and 20k, it is very fast and when I tighten the nut between the seat and the wheel some more, I'm sure it will be a nationally competitive car.   In order for us to get to that number, we bought a very strong motor from a teammate that only had a two-three weekends on it, has already won a race or two in the sediv, has been whistled, and checked for compliance and it is all set.  If we were to buy a new motor (not build like you), I do not think we would have been able to get under the 20k mark for a frunt running car.   We had jeff/cory at autotechnik do some of the big things like the cage but we built the whole rest of the car in 4 weekends ourselves.  Which isn't bad for our first time so we didn't waste too much time of our own labor.   

 

 

However, we already had the traqmate, transponder, transmission, radios etc which may push the total value of the car over 20k but I believe it is possible to build a front running car under 20 without all the bells and whistles.  Good luck to the rest of your build, interested to see how your car performs against good competition.

[speedengineer]

we just built our 99 in the range between 15k and 20k, it is very fast and when I tighten the nut between the seat and the wheel some more, I'm sure it will be a nationally competitive car.   In order for us to get to that number, we bought a very strong motor from a teammate that only had a two-three weekends on it, has already won a race or two in the sediv, has been whistled, and checked for compliance and it is all set.  If we were to buy a new motor (not build like you), I do not think we would have been able to get under the 20k mark for a frunt running car.   We had jeff/cory at autotechnik do some of the big things like the cage but we built the whole rest of the car in 4 weekends ourselves.  Which isn't bad for our first time so we didn't waste too much time of our own labor.   

 

 

However, we already had the traqmate, transponder, transmission, radios etc which may push the total value of the car over 20k but I believe it is possible to build a front running car under 20 without all the bells and whistles.  Good luck to the rest of your build, interested to see how your car performs against good competition.

 

Thanks for the data point, John.  Glad to hear you're happy with your car for that price range.  Mine hopefully will be similar.  Just cheaper yet - I expect to save ~$8 by doing the cage and the motor myself.  That's really the big savings here.  Takes a $20k car and makes it $12k.  Or if I throw $3k of data system and vinyl at it, it's still a $15k car.    I hope...

[speedengineer]

I could use some help from the experienced around here understanding what makes a valve relief cut legal.  I do not find the wording to be sufficiently clear to define the allowed depth of the cut.  What 'edge' are the rules referring to? 

 

Rules excerpt:

Unshrouding of the valves is limited to the dimensions in the chart below. There must be a sharp
edge where the valve relief cut meets the chamber. That edge must be present and unmodified.
This area is not to be blended by hand, machined, or chemically processed to create a smooth transition.
This dimension will be measured with go/no go tooling. The maximum dimensions are listed below,
measuring guide centerline to chamber edge.

 

Ok, there has to be a sharp edge.  Got it!  But, which edge and where can it be located?  Please consider the following mspaint example I drew up.  Are these both legal?  Both will have a sharp edge at the intersection of the cut and the chamber, just in different locations... 

 

 

 

 

 

 

[Johnny D]

I'm not sure if this helps at all. And I think there's a pic out there too I'm looking for in the Fastracks after this (may)

http://mazdaracers.c...ge-1#entry77329

 

J~

[Johnny D]

Here's a clarification
http://cdn.growasset....pdf?1441316758

J~