http://mazdaracers.c...ential-housing/
gusseted rear diff housings
#1
Posted 07-12-2017 01:20 PM
#2
Posted 07-12-2017 02:33 PM
The ones we weld up all show signs of cracking before we repair them.
- Jim Drago likes this
V2 Motorsports
#3
Posted 07-12-2017 05:44 PM
#4
Posted 07-12-2017 05:56 PM
Have to ask the obvious question...legal? Didn't the gussets for the sub frames have to go through an approval process? Dont get me wrong...I want to know this can be done...all for it!!!
Your ad is for a complete welded housing correct Jim? Can someone buy the piece you weld in if they have the ability to weld themselves?
Ron
RAmotorsports
#5
Posted 07-12-2017 06:08 PM
Do these all just break on the one side?
yes, they are designed to break there.. why the little notch
East Street Auto Parts
Jim@Eaststreet.com
800 700 9080
#6
Posted 07-12-2017 06:20 PM
Have to ask the obvious question...legal? Didn't the gussets for the sub frames have to go through an approval process? Dont get me wrong...I want to know this can be done...all for it!!!
Your ad is for a complete welded housing correct Jim? Can someone buy the piece you weld in if they have the ability to weld themselves?
Ron
I lost a very good shot of winning the Nola Saturday race because of this, Craig lost a Sprints podium bc of this. I'm not falling in that camp anymore. It is legal for us to repair these cases. I prefer to start with virgin ones than weld two pieces back together. As Ralph pointed out.. "They are all starting to show a small crack at the notch". The "crack" is now welded and under that plate, thus a repair, not a modification. It is a designed failure point. No advantage other than it allows you to finish races that you otherwise wouldn't when some #%^&* decides to slam into the rear of your car. It would be a weeny protest.
Jim
- Ron Alan and Michael Novak like this
East Street Auto Parts
Jim@Eaststreet.com
800 700 9080
#7
Posted 07-12-2017 06:35 PM
The reason they are designed to brake there is for crash test requirements. Since the engine is attached to the diff the only way for the engine to absorb the energy is to move rearward in a fontal crash and snap the diff housing. Part of meeting FVSS standards to be sold as a street car.
when we get ass packed the engine wants to accelerate rearward (rubber mounts) while the car wants to accelerate forward.
- Danica Davison likes this
V2 Motorsports
#8
Posted 07-12-2017 06:48 PM
Ron
I lost a very good shot of winning the Nola Saturday race because of this, Craig lost a Sprints podium bc of this. I'm not falling in that camp anymore. It is legal for us to repair these cases. I prefer to start with virgin ones than weld two pieces back together. As Ralph pointed out.. "They are all starting to show a small crack at the notch". The "crack" is now welded and under that plate, thus a repair, not a modification. It is a designed failure point. No advantage other than it allows you to finish races that you otherwise wouldn't when some #%^&* decides to slam into the rear of your car. It would be a weeny protest, but one I feel I would win every time.
Jim
Jim was the Diffs that you broke on a virgin Diffs or had you filled in the notch with weld and that was not good enough?
I have just filled the notch on several spares and I have one that is plated like yours.
I was thinking that just filling in the notch was good enough, I lost two Diffs in one weekend a few years back at MIS (Michigan international), so i can vouch for the necessity of the "repair"
Frank
TnT Racing
SCCA Ohio Valley Region
#9
Posted 07-12-2017 07:12 PM
Someone else asked and I'll ask where is the Mazda FSM process or SCCA rule which makes this notch/plate welding legal?
#10
Posted 07-12-2017 07:29 PM
It seems a stretch to call adding the plate a repair. If that is a repair why do the subframe braces need to be approved parts? Also if the purpose of the notch is to allow the engine to more easily move backwards in a crash, should extensive gusseting be done? It seems the work effectively reduces the front crush zone affectiveness.
#11
Posted 07-12-2017 07:31 PM
The rules specifically mention differential housing repair in 9.1.7.C:
It is permitted to use industry standard procedures to repair damaged non-engine components (e.g., welding a transmission or differential housing).
#12
Posted 07-12-2017 07:34 PM
Ron
I lost a very good shot of winning the Nola Saturday race because of this, Craig lost a Sprints podium bc of this. I'm not falling in that camp anymore. It is legal for us to repair these cases. I prefer to start with virgin ones than weld two pieces back together. As Ralph pointed out.. "They are all starting to show a small crack at the notch". The "crack" is now welded and under that plate, thus a repair, not a modification. It is a designed failure point. No advantage other than it allows you to finish races that you otherwise wouldn't when some #%^&* decides to slam into the rear of your car. It would be a weeny protest, but one I feel I would win every time.
Jim
I was trying to save David a post but he cant resist!
Having had my cars be a victim of this failure in a minor contact...I'm all for the repair/mod. Could the cracked subframes be repaired anyway one liked when they broke? Industry standards may be a tough argument?
Ron
RAmotorsports
#13
Posted 07-12-2017 07:42 PM
#14
Posted 07-12-2017 09:07 PM
#15
Posted 07-12-2017 09:15 PM
The rules specifically mention differential housing repair in 9.1.7.C:
It is permitted to use industry standard procedures to repair damaged non-engine components (e.g., welding a transmission or differential housing).
I saw this, but welding in a plate to strengthen a part goes beyond welding to repair something. Repair is mending or restoring. The plate makes the part stronger than original.
#16
Posted 07-12-2017 09:18 PM
I agree the plate is illegal for the same reason roll cage mounting plates are limited in size. I'm okay with it though - let's add it to the rule book and move on.
I agree. Adding it to the rulebook is the way it should be handled.
#17
Posted 07-12-2017 10:13 PM
While we are at it...lets make it ok to keep or remove anything under the dash! We are beyond show room stock...we don't need heater cores or fans or anything related. We need to eliminate the "non performance argument" from peoples minds and just let things that don't matter go!
We now have the ability to buy longer lasting bearings...they are not a performance advantage unless you consider finishing/avoiding a failure in a race an advantage. See where I'm going here! Lets clarify a whole lot of ticky tac shit within the rules and fast track this kind of stuff to benefit all!
- dstevens likes this
Ron
RAmotorsports
#18
Posted 07-13-2017 04:47 AM
Wow, I got roasted when I suggested removing wire from the harness in the name of "and system"(e.g. remove radio and system,airbags and system), and moving the ignition switch to get it away from my kneecap( the switch and lock cylinder would not be changed or modified, just moved and fall into the non performance enhancing comfort and convenience area ). However no one has any problem with starting down the slippery slope to a Prod Car by gutting the under dash area and installing start buttons and full on race hubs? it's getting bad enough with engines and driveline costs.
I have no problem with Jim's plate and welded housing, and the front subframe gusset, let's just be aware that sooner or later someone will suggest to alleviate continued front subframe failures, we need a fabricated subframe out of tubing,or to lower the cost of crash repair lets use fiberglass rear quarter panels held on with Dzues buttons.........Maybe we need to dial back the performance with a smaller,less grippy tire, like some have suggested in other posts, or go back to a max camber rule to dial back the string of parts failures?
#19
Posted 07-13-2017 06:38 AM
How many diff. housings break that have not been subject to bump drafting?
EDIT:
Not necessarily at bump drafting moment of impact, but at a later date.
#20
Posted 07-13-2017 06:42 AM
- Danica Davison likes this
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