​​​​​​​bummer and that's probably the source of the problem.

 

Don't make assumptions. This was a 150k mile engine that I boosted at 151k. It ran great for 6-7k miles on an evans tune that entire time.

I simply decided to do a refresh of the motor as I saw/read some F22 refresh options that inline pro offered, just due to the mileage of the motor and my future plans of tracking, I thought it a good idea. This is when it all started.

Inline pro told me on motor #1, don't worry, the current tune will be fine, don't bother getting it retuned... despite them offering their own tuning services!! Motor blew for obvious reasons, I'm ashamed for not knowing better but I trusted the supposed #1 shop for F engines.

Motor #2, rebuilt this time with new(to me) block, oversized CP pistons, Inline pro rods, ARP everything. Inline pro tuned the car this time, I broke it in on their tune per their advice for about 5-600 miles. I then (with their blessing) trailered the car for a full dyno tune at evans. The pistons scored the cylinder walls so bad on the dyno the motor was blowing the dipstick halfway out of the hole at WOT. Got home, scoped the cylinders and that was all she wrote for engine 2.

Now #3 is another new (to me) block, 10:6:1 CP pistons, inline pro rod, ARP everything, evans tuned again and here we are a year later.

 

what was the verdict with #1 and more specifically #2 since it went from shop to shop

 

#1 was the motor blew because it needed tuned despite them telling me it didn't. Before rebuild it was 18% avg leakdown and after rebuild obviously much less, so yeah it needed fully re-tuned. They told me it didnt.

#2 I really never received an answer as to what the root cause was. They just rebuilt it on their dime and said it was fixed since it was lower comp pistons this time for safety.... even though all I was trying to do this entire time was run a 3.4'' pulley on a brand new SOS stage 2 system - total cookie cutter build.

 

wait wait wait wait, they ran CP pistons on stock sleeve for motor #2? what CP pistons were they?

 

I would just source a k24 and be done with it. This is what I will do when my F20 blows... These engines have become too expensive and too scarce to even bother building anymore.

 

Here's the email: Hi Dustin,

Here's the list of the main components in your engine (short block).



Custom FRM 87.50mm bore 10.6:1 compression Turbo Forged Flat Top CP pistons with rings and wrist pins

Inline Pro HD H beam connecting rod set with 3/8" ARP2000 bolts

Stock F22C crankshaft



Piston to wall clearance .003"

1st ring gap .022"

2nd ring gap .026



*If you're trying to reference or compare these clearance numbers for build tolerances, please keep in mind this is an engine that utilizes Honda's "Fiber Reinforced" (FRM) sleeves. Traditional engines with iron sleeves use different tolerances for their builds.

 

I thought Mahle was the only company that made aftermarket pistons compatible with our cars?

 

I did PM you by the way.

 

According to inline pro these CP pistons are coated somehow to be compatible with FRM.