Upgrayedd

iTrader: (1)

I was finally able to remove and replace my powerplant frame this morning. I knew it was in two pieces but didn't realize how bad the break was. I purchased a used ppf off of another forum member locally some time ago and recently had it reinforced by another local forum member. Should help prevent a repeat. Here are some pictures of the newness and the carnage.

Broken ppf






Reinforced replacement






Side by side

MichaelB145

I have broken a few but never in half like that! I need to figure out the best way to reinforce mine like that!

TimmyFD

iTrader: (7)

looks good. tell whoever welded it to turn their wire speed down and maybe the voltage up a bit, it will help the penetration. what where you doing when the original broke?

MyRedFD

iTrader: (1)

I was thinking the same thing about the welds. I've never seen one break in half like that before either.

Upgrayedd

iTrader: (1)

I'm not really sure of the exact time when it broke but I know I was on the street, not track, and I got some wheel hop on a hard launch on a back road and it snapped. Car's been out of commission for some time due to emissions failure.

He was welding with the welder plugged in to a 15 amp circuit, when he switched to a 20 amp circuit it got better. He was constantly having to tweak with it cuz some areas didn't want to accept the weld and others welded like butter. I'm pleased with how it turned out and will be adding a diff brace in the future to help stiffen the drivetrain and aide in the fight against another broken ppf

hsitko

iTrader: (1)

You may have done your self a disservice by having that done. The next thing you may be replacing now is your diff. That beam (ppf) is supposed to flex. You just made it not flex. Do you have good new engine mounts, solid diff mounts? I understand that you are getting a diff brace that is a good thing. But man, that is usually a symptom of big power or other broken parts.

Upgrayedd

iTrader: (1)

Still running the original stock motor mounts and diff mounts. My current set-up is probably only good for about 330whp tops. I hadn't had any symptoms of a problem with any other bad parts prior to the ppf braking.I'm thinking it probably got worse over the remainder of time I drove it once it broke. It's an odd break pattern. I'll find out more once I am able to drive the car. Keep in mind Hank this car gets driven extensively maybe 2-3 times per year. Other than that it's jut run around the block to keep the fluids fresh. I'm slowly working my way up to a solid drivetrain and new motor... I've seen this done before with success so decided I'd copy it. I don't foresee any problems

RX7 RAGE

iTrader: (22)

That is some serious carnage.

zack4173

iTrader: (3)

It looks good to me Im glad you finnaly got that thing reinforced it has been a long time coming.

RotorMotor

iTrader: (5)

i hate to be the one to point this out, but it looks like you reinforced every part EXCEPT the area where you snapped your last one. and, with the added rigidity of the rest of the PPF now, any flex in the PPF will be amplified at that weakest section that is not reinforced. the same weak section where you snapped the last one. i think this may be worse than no reinforcement. i hope im wrong -Heath

Upgrayedd

iTrader: (1)

I tried to get as much added steel to the portion where I had seen the crack in the bottom of the ppf. Problem was I couldn't get a good view of how broken it was when it was in the car and the contours of the ppf make it hard to mold the steel to it. I don't think I'll have any problems with it due to my driving style. And typical weak points of the ppf are the mounting points. Where I broke mine was the thickest part where it's 3 layers thick! I don't plan on drag racing the car or launching it. And I seldom drive it.

wanklin

iTrader: (2)

The fingers and loop portion will snap next. You must have bad engine mounts for it to go the way that it did.

Upgrayedd

iTrader: (1)

I guess we'll see... If I snap the ppf again I'm not too worried about it. It's a $50 part locally

islanders_rx7

iTrader: (4)

That what I was thinking exactly! The PPF has the holes/intercostals for that very reason.

islanders_rx7

iTrader: (4)

Good price! I wish I could of found a deal like that.

Upgrayedd

iTrader: (1)

That of course is a used price.

I just completed my short and limited test drive around my neighborhood. All feels well. Shifts are crisp and smooth and I don't seem to have any symptoms of other problems.

Phaz

wow ive never seen one brake like that, if your reinforcing, ive added to your pic were mine broke weekest part i would say, marked in orange

Dudemaaanownsanrx7

iTrader: (23)

i broke my ppf also, but not in half like that!
i managed to weld mine up and reinforce it. then i added a tranny brace, and solid differential mounts, nothing budges at all now. Solid more accurate shifts.feels so much better. i suppose something else will find its way to breaking at some point, and i'll cross that road when it gets here. fast cars always have that on going battle of increasing power, breaking ****, adding more steel, then breaking something else. It's the cycle of life.

Upgrayedd

iTrader: (1)

Interesting PHAZ, other than mine I've never seen one break anywhere other han the mointing points.

hsitko

iTrader: (1)

A $50 dollar part maybe, but a waste of time if you break another one without properly checking the power plants mounting points themselves. Not being mean, just sayin. 15 minutes of inspection may save you hours of work and modification of parts that would otherwise work fine. I'm not a betting man, but i would make a wager that you have a problem hiding somewhere in there.

Upgrayedd

iTrader: (1)

Well I've yet to find anything, Hank. I did have the car up on a lift months ago which is where I discovered the break in the girth of the ppf. I suspected a problem near the motor/tranny or diff (mainly the "fingers" of the ppf) and found nothing. Then found the break right where the shield was mounted to the ppf. The car was driven on occasion with the broken ppf so I don't think the break was all at once. But if there is another problem it will get fixed as the next step in my "build" is the motor. Just gotta get my income stream going again.

Don't worry Hank I don't take offense to opinion. I appreciate your honest input.

seanfd3s

ouch

Julian

iTrader: (14)

As to stiffening the PPf and damaging Diff. In reality you probably marginally stiffed beam but definitely weakened it and added weight. A beam gets its beading stiffness from the top and bottom flange the web with holes is for shear strength ( primary job for vertical stiffness is to keep top and bottom flange a contract spacing apart as beam is bent, hence the lightening holes) if holes are too many beam can shear , but your reinforcements are patches with stress risers so beam would still shear between strapping plates. Secondly that steel is HS probable 50 to 70,ooo psi yield and MS PPF is 60 to 85 psi, that type of steel requires special welding procedures, with HS rods and control temp input and cool down so as to not temper the parent metal (i.e. soften and lower strength level) or embrittle it and make crack more of a problem. Next time if you really do want to weld in the PPf run a continuous strap top and bottom (I do not know if it will fit) about 1 in wide and length of beam, weld with M10018 rods and after heating beam to about 150 degrees and allow to cool down under appropriate insulating blanket. or better yet find out what is loose and making it break. After all Mazda didn't stiffen the MS PPF just strengthen with Higher strength steel. For a given type of material (steel in this case)Stiffness comes from geometry, and amount of material; strength comes from strength of material (steel ranges from yield strengths of 34,000 psi to 200,000 psi, but they are all steel and have the same elasticity coefficient and or amount.