My PPF cracked completely a few days ago and I'm a indecisive as far as what upgrade to go with. I was hoping anyone has some recommendations or info about how to go about this. Repairing the original PPF is 100% out of the question. I'd have more peace of mind having it replaced or eliminated. I just do some spirited driving, not planning on doing any track days but would like to have a track ready upgrade.




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Options 1: Sikky Mazda RX7 FD3S Heavy Duty PPF / Differential Brace
This is the option I wanted to take initially because I saved money on not buying a replacement PPF and I also eliminated the PPF. However, I have not been able to find any concrete info on someone using this. Just some criticism on it being mounted on the floor which can cause cracking of the floor.

Option 2: HPP-2 in 1 brace and replacement PPF
There is more info available about the ​​​HPP-2 in 1 brace. My biggest concern is that I would have to get a replacement PPF which would go from a $500 upgrade (brace) to additional cost for the PPF. I was thinking about the RE Amemiya PPF or trying to find a MazdaSpeed PPF, but that would double the cost of the repair. I don't mind spending the money on a replacement PPF, but I rather spend it on an other upgrade.
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Option 3: Good used stock PPF. The PPFs really are only failure points on very high horsepower cars or cars that have a lot of hard drag racing launches.

The Mazdaspeed/RE-A PPF's are IMHO not worth it at all. I think they're mainly a paint job.

Are you making a ton of power or doing drag racing?

Dale

 

Ive considered just doing a replacement but something about doing an upgrade really snaps me out of doing OEM repair LOL. And I checked the market place, I didn't find a PPF in the first 7 pages.

Right now I'm close to 400hp but my motor has lowish compression so once it gives out, I'm planning on building something that's in the 500hp range. I don't plan on doing any track or drag right now but that's due to the low compression. Who knows, one I get a rebuild done, I might take it to Irwindale or Willow.

 

^Post a wTB. They are out there but not much demand so they don't get posted.

 

I would get a good stock PPF and maybe look at doing a trans or diff brace.

Yeah, post a WTB, I think one will pop up for you.

I think you need to put the money into other aspects of the car than a fancy PPF that probably won't get you much more than stock.

Dale

 

So your recommendations would he replacement PPF and a diff brace like the HPP 2-IN-1? Do you think a transmission brace would he necessary if I go with a PPF replacement or Sikky brace?

Transmission Crossmember

 

Damn. Someone has done more than “spirited driving” to do that. Previous owner? And I don’t think it’s JUST a case of a lot of power. I agree with the above…get a good used PPF from one of the trusted sources here. If you’re not concerned with nvh, reinforce the driveline with any of the trans or diff braces, good engine mounts (if you don’t already have them) and stiffer/poly differential bushings.
Sidenote…maybe I missed something over the years but I’ve never seen anything conclusive on what makes a MAZDASPEED PPF functionally stronger, even if you could find one.

 

I've owned the FD for about two years now. Sadly, the previous owner really neglected this FD. It was missing those aluminum tunnel braces. I've had to replace a lot of things already but I got a good deal so I'm not really complaining. She's being well taken care of by me, just slowly.

What is NVH? All bushings have been replaced and I believe the motor mounts are upgraded.

 

Noise, Vibration and Harshness related to suspension and tires.

 

Good to know. This is a weekend car, more like every other weekend car, so NVH is not important at all. I'm already running pretty low with stretched tires so I'm already having a rough ride.

 

Mazdaspeed say in their brochures where it was sold "The Mazdaspeed power plant frame is made from hot-rolled steel plates instead of the stock steel stamped piece and is 10% stiffer. The extra stiffness reduces drivetrain bending and flexing due to on and off acceleration."

I got mine because it matches the red Autoexe braces and looks cool when on the lift and being an FD, it's in the air a lot of the time .

 

and on your roof in a sand trap

 

No technical background but I thought it was just the opposite…cold stamping/rolling produced a stronger result with better tolerances.

 

I had no idea that sort of damage to the PPF was even possible, I'm impressed. Anyways, I definitely recommend the transmission brace, as I have the same one at your power level. I actually don't have a diff brace because I don't drive my car like that and haven't felt the need for it, but if your doing any hard launches I'd recommend doing both.

 

It sounds like the manufacturing method is different, not just material. High volume stamping makes you to sacrifice features/geometries. Doing it with plate at low volumes doesn't have the same restrictions.
It's probably something like the wall thickness in the sharp bends are slightly thicker. That's why nobody can spot the difference and parts are the same weight.
Either that or red paint is now structural

 

Or the little MAZDASPEED serial number tag is strategically riveted over a known weak-point to add the claimed strength.

 

For resulting material properties, you are correct. However, for overall design and strength, there are always limitations in production part design that can often be overcome in fabricated parts.

 

My car came with a badly cracked PPF when I bought it.
I was able to find a RE-Amemiya one at a reasonable price. From comparing it side by side with an OEM brace, the RE-Amemiya PPF basically is an OEM brace that has been significantly reinforced with additional & bigger welds and extra bracing added.

My best advice is to get an OEM PPF and try to reinforce it yourself with some strategically placed welds and maybe also some bracing, to in a way, copy the design of the RE-Amemiya. It will be cheaper and much easier to find.

Second, GET A GOOD DIFFERENTIAL BRACE/CAGE! (It will help prevent any future cracking of the PPF)

 

In this day and age you don't have to accept having a rough ride. You can have a car that drives relatively smoothly yet can still turn corners and perform amazingly.

That said, if you have stock diff and/or motor mounts that's the first thing to work on after replacing the PPF.

Dale

 

I would think a stock PPF with key reinforcement welds would do the trick. Has anyone tried that?

 

I read on here some people add some welding and reinforcement. As far as how or where exactly on the PPF, I'm not sure.

 

Dale is right, replacing your motor mounts + a good diff brace = important.