@pete.lete - Gridlife StreetMod Build - Team Falken

[Butterman]

I know it's been a while and I'm not sure if someone's told you since but rods snapping under deccel at high rpm is very common for a couple reasons. So by looking at your rod it's clear that it failed under tension, because it's torn in half and not bent, which indicates that it failed during deccel.

There's a compounding issue here. When you're decelerating the tb is closed so when your intake stroke happens the piston can't pull in fresh air and instead pulls a vacuum which causes a tension force in your rod. This combines with the tension forces in the rod caused by the centrifugal force of spinning this whole chunk of machinery (this force exponentially increases with rpm). At the same time these forces stretch your rod and actually reduce the cross sectional area of your rod. Which means less material to support the increasing forces aka an increase in stress.

Unless you had pinging/detonation which previously damaged the rods then this probably had nothing to do with boosting your car, this could have happened to an NA motor. In fact, this shows that your tune and boost weren't the issue.

[StraightOuttaCanadaEh]

Originally Posted by Butterman

I know it's been a while and I'm not sure if someone's told you since but rods snapping under deccel at high rpm is very common for a couple reasons. So by looking at your rod it's clear that it failed under tension, because it's torn in half and not bent, which indicates that it failed during deccel.

How would one go about preventing this from happening? Avoid lifting at high rpm?

[Butterman]

Exactly. If you keep your foot on the gas slightly while you brake you'll keep the tb open and reduce the vacuum and thus stress in the rod. It's not a perfect solution but it'll help prolong the life of your rods.

I'm not sure if the ecu has this already but you might be able to do this with just a tune or a standalone. You could program the tb to stay open under certain deccel conditions but just cut fuel or spark.

[pgranberg11]

Originally Posted by Butterman

Exactly. If you keep your foot on the gas slightly while you brake you'll keep the tb open and reduce the vacuum and thus stress in the rod. It's not a perfect solution but it'll help prolong the life of your rods.

I'm not sure if the ecu has this already but you might be able to do this with just a tune or a standalone. You could program the tb to stay open under certain deccel conditions but just cut fuel or spark.

this is an interesting concept. another member on here had a similar scenario, however their motor didn't grenade itself, just bent/pulled the rod enough that it deformed and started making noise. After some research it seems to me that your comment agrees with my research. I've been very careful to not abruptly lift off the gas when I need to start to decelerate. I try to slowly reduce gas pedal input until I can "safely" completely lift so there's no snapping/bucking motion in the car itself. I must say, I need to be very graceful in terms of being able to do such a thing.

[Lantanafrs2]

I like your car and appreciate you sharing your experience with us.

[WC-BRZ]

Great thread - lots of learning going on in here so thanks for posting your experience.

I noticed you're running the 18x9.5 for RPF1s as opposed to the typical 17" sizes for track days. Any issues with rubbing especially during track days or spirited backroads/canyon runs?

[pgranberg11]

Originally Posted by WC-BRZ

Great thread - lots of learning going on in here so thanks for posting your experience.

I noticed you're running the 18x9.5 for RPF1s as opposed to the typical 17" sizes for track days. Any issues with rubbing especially during track days or spirited backroads/canyon runs?

Sorry that's been a month since me replying...

Part of it is that I like the look of 18s.. imo they fill the space nicer. Also, I wanted 9.5" wide wheel for the power I'm making. It allows me to run a wider tire if I need to better than just a 9".

However, I did play with the idea of going down in size again for weight reduction.. but I haven't been convinced yet.

No rubbing whatsoever. I run a -3.5 camber in the front and -2.5 in the rear.

It did seem like I rubbed when my camber was any less than -2 in the front. (my paint chipped off and now rust is forming ) The back has never rubbed for me though.

the only other thing that does rub is my verus brake ducts, but only a little bit and it's not even a big deal. I'm running 2 spacers that came with the brake ducts to prevent more rubbing. So I've limited my steering radius a little bit. Again, no big deal since I don't need the wide turning radius when I'm on track.

[pgranberg11]

Hey guys, it's been awhile since I've posted.

Here's a track day from Autobahn Country Club in Joliet, IL with Gridlife.

I've currently been testing the new Stoptech C43 front bbk as well as a "proto-production" REAR big brake with a c42 caliper by Stoptech.

I will have another video explaining the few things with some shots of the C42 sooner or later.

[ame]https://www.youtube.com/watch?v=WVVgMIxvTHI[/ame]

[pgranberg11]

I'll just update this with some text before I send out a video since I'm already on here. This is NOT yet available yet as this is a proto-production and we're still field testing these. Once tests have been finalized they will be available for public purchase.

Additionally there are TWO versions of this kit. There's the touring model and the racing model. The touring model retains the ebrake and uses a 1pc rotor. The racing kit does NOT use the ebrake and uses a two piece rotor, therefore is lighter overall. BOTH kits use the same C42 caliper and DR22 pade shape.

Touring Kit:
316x20, slotted, OEM WRX SIZED rotor. C42 Caliper
Caliper Weight: 3.2 lbs each
Stoptech slotted rotor weight: same as OEM?

Race Kit:
298x21, Pillar Bi Slot, C42 Caliper
Caliper Weight: 3.2 lbs each
Two Piece Rotor Weight: under 10 lbs

Feast your eyes on a REAR bbk made by StopTech:







For more information on their big brake kits check out this link:

https://www.apcautotech.com/product/...kits-race-kits

[pgranberg11]

As promised, here's the video!

[ame]https://www.youtube.com/watch?v=kpigGUYtQPg[/ame]

[pgranberg11]

Recent track footage from West Michigan Honda Meet

[ame]https://www.youtube.com/watch?v=avW9igzQbjA[/ame]

[pgranberg11]

[pgranberg11]

[pgranberg11]