• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Dodge, Jeep and RAM Forum dedicated to FCA owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the SRT Forum today!


Some testing of the injectors

Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,069
Reactions
15,536
Likes
402
City
Murfreesboro
State
TN
Country
United States
Vehicle
2016 Hellcat Go Man Go
#1
I wanted to make sure I wasn't having any fuel delivery issues that may have contributed to the engine failure. One of those "had to know" deals.

This is what I found.

 


coolblue

1000 Posts Club
Founding Member
Donating Member
Member ID
#1172
Messages
1,577
Reactions
2,695
Likes
162
City
Long Island
State
NY
Country
United States
Vehicle
2019 Redeye
#2
I wanted to make sure I wasn't having any fuel delivery issues that may have contributed to the engine failure. One of those "had to know" deals.

This is what I found.

I been working late lately and just getting on to the computer at night to see some funny meme's and hop off. I wanted to read some of Mike's analysis but again it was late and I'm a little wiped out, gonna look this weekend. I know the vid was about the injector status, but you got a real good shot of that piston rod combo. All I can say without deep thought/analysis is that, that piston looks like a race piston. That's a real short ring stack, and the skirts are short also with no real extension.(i.e. . prone to instability). I have no real experience with the new gen hemi but the old Chevy's had a much longer piston than that all around. Something racy, that looked like that sometimes had Teflon buttons on the skirts also.(none of which was meant for long term service duty). The rod is bent out of the plain of motion of the assembly. With the tremendous pressure of a blown motor and the extreme weight of these cars (kinda acting as a "brake" if you will) the forces are gonna look for the weakest link to give. Maybe with the extreme short ring pack and NO skirt at the side wall, the piston bends at the "hip" fractionally and under TREMENDOUS pressure bends the rod and it takes the pin with it.
Also, maybe the number seven deal has to do with the inherent harmonics of the crank/hemi design. Sometimes it's amazing to see the movement in mechanical things when taken with a speed camera under use and speed that cannot be seen with the eye.
 


Last edited:

FFBOS

500 Posts Club
Founding Member
9 Second Best E/T
Member ID
#1008
Messages
692
Reactions
1,180
Likes
132
City
Mount Prospect
State
IL
Country
United States
Vehicle
2016 Hellcat Charger
#3
Any idea what fuel those bent rod samples were using?
 


OP
Speedy!

Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,069
Reactions
15,536
Likes
402
City
Murfreesboro
State
TN
Country
United States
Vehicle
2016 Hellcat Go Man Go
Thread Starter #4
I believe those were out of a 2.85 pullied car running 93. The information I received was poor tuning, too much timing, knock sensors turned off, and lean.
 


BULL

Oh NO! Not that guy!
Staff Team
Founding Member
U.S. Marine Veteran
Donating Member
HFCOTM
Wiki Contributor
Member ID
#1079
Messages
14,587
Reactions
44,746
Likes
402
City
Weld County
State
CO
Country
United States
Vehicle
MY16 M6 Challenger Hellcat
HFCOTM
View Images
#5
Injector service retail cost?
 


BULL

Oh NO! Not that guy!
Staff Team
Founding Member
U.S. Marine Veteran
Donating Member
HFCOTM
Wiki Contributor
Member ID
#1079
Messages
14,587
Reactions
44,746
Likes
402
City
Weld County
State
CO
Country
United States
Vehicle
MY16 M6 Challenger Hellcat
HFCOTM
View Images
#6
BTW, 93ish down to 88ish is 5%ish

That's a notable decrease in fuel delivery if you ask me.

.02
 


FFBOS

500 Posts Club
Founding Member
9 Second Best E/T
Member ID
#1008
Messages
692
Reactions
1,180
Likes
132
City
Mount Prospect
State
IL
Country
United States
Vehicle
2016 Hellcat Charger
#7
I believe those were out of a 2.85 pullied car running 93. The information I received was poor tuning, too much timing, knock sensors turned off, and lean.
Seems to be the case in "most" failures eventually. The car could of lasted quite a bit of time in that condition before the actual failure. E85 guys who have either run too poor of content for their high timing tune, and/or pushed their flex tune setup on a small pulley too far (mixing in too much 93) have had some sore of "pre-event" before the motor said bye. Melted plugs, etc. Month or two later = Rod gone
 


coolblue

1000 Posts Club
Founding Member
Donating Member
Member ID
#1172
Messages
1,577
Reactions
2,695
Likes
162
City
Long Island
State
NY
Country
United States
Vehicle
2019 Redeye
#8
In round numbers the crank spins and pistons go up/down 100+ times a second.(@ avg. 6200RPM) Through a run it spins 1000+ and gets shock loaded (gear changes) @ every200+ revs on average. I could see damage occurring at the metallurgy/molecular level and lasting awhile but actual physical damage would only go a short time (the 3 runs that day?) unnoticed before becoming catastrophic. IMO.
Also getting back to the "harmonics". The 2-7 pistons are next to each other in the firing order but are on complete opposites sides of the crank in the physical end of the equation. Crank is a fulcrum, hit it hard on one end the other is going to have a reaction. Don't know, just a thought.
In reality we're just batting around ideas which is interesting and what this forum/thread is all about. If you just had the 'get'r done' mentality you could/would just build it bigger better forge it and be done. But then it would never really be figured out which is the interesting part in, again MO.
And there would be no forum at all. LOL.
 


Last edited:
OP
Speedy!

Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,069
Reactions
15,536
Likes
402
City
Murfreesboro
State
TN
Country
United States
Vehicle
2016 Hellcat Go Man Go
Thread Starter #9
Cost to inspect/clean the injectors was $20/per if I remember correctly. Complete bill with shipping was $171.06.
 


MikeD1

4000 Posts Club
Founding Member
Premium Account
HFCOTM
Member ID
#1026
Messages
4,001
Reactions
16,077
Likes
302
City
Central Florida
State
FL
Country
United States
Vehicle
2016 Challenger Hellcat
HFCOTM
View Images
#10
Totally off topic, but which brand/model shaft drive opener is that you have on your new garage doors & do you like it ??
 




Top