Randy_S

iTrader: (1)

Ok, this is like Where's Waldo. Can anyone find the problem spot on this motor. It only had 3,400 miles on the clock with no spray/charger and no track time at all. Hope yall enjoy my agony.

ex-SS-ve

iTrader: (9)

this the 408?

Randy_S

iTrader: (1)

Yup, it wasnt my heads afterall.

NemeSS

iTrader: (127)

is that one of the slp shortblocks that had bad pistons?
looks like mechanical failure, not tuning failure, idk

Randy_S

iTrader: (1)

NO, it was built locally. I am being told initially that it was possibly caused by detonation issues.

I wont involve any names in the build as I still think it was something mechanically "bad part" and I just now need to know who and how its going to get fixed. I will be contacting the installation shop shortly after I know more about why the failure happened. It should have a warranty, we will see how that works out.

chupr0kabra

iTrader: (10)

Good luck!


-Mike

A-Dub

iTrader: (6)

Another #7 goes down.

If you think its mechanical, start with the build sheet and make sure the rings used were designed for the pistons used and that the rings gaps are correct

Randy_S

iTrader: (1)

It was my 2nd #7 piston to screw up! Thats why I built the 408 in the first place!

The1N_only

iTrader: (7)

well if this is your second motor you've lost because of the same reason... you might want to try to figure out whats causing that so you dont lose another

connexion2005

iTrader: (49)

well i believe he is saying he lost #7 on his stock 346ci which is typical on an ls1 and now #7 on his 408ci which may be mechanical failure.

Randy_S

iTrader: (1)

Thats exactly what I am saying.

Most of us know that the #7 is a weak spot in a stock LS1 but not necessarily in a stroker. I dont know how or why this happened, looking for some clues and thought maybe one or two people on here could help.

connexion2005

iTrader: (49)

Yea I always wondered what was going on with number 7. I ran a compression test on mine about 2 months ago and than god number seven still pops out 170psi. I've always wondered if it had anything to do with the pcv outlet being on the valve cover above that cylinder but dont see how that could relate...good luck with your new build. I know my days are numbered for a project like this and it makes me sick for ya that this happened. Are you going to try and just swap the piston and rings on number seven only? Its something I would look into after getting it checked out for an ok...

Randy_S

iTrader: (1)

I believe that the piston can be replaced and the cylinder honed out. The heads have to be worked on as it now looks like the top of the piston. I think everything will be worked out.

Once again, just looking for some input to see if anyone would know why this happened.

BigBronco

iTrader: (2)

Either the rings Butted and caused the ring land to break, or you had a crappy tune with a good amount of Pre-ignition.

chriswtx

iTrader: (5)

who made the pistons?? and what were the piston ring gaps? If you don't know, you might want to pull that piston and measure the ring end gaps just so you know for sure...Hopefully the bore on the block is not cracked like mine did...

GS WS6

Have you checked to see that the number 7 injector is working properly??????

red90cobra

iTrader: (36)

i was thinking this also.

Randy_S

iTrader: (1)

The injectors are brand new. The only old thing that the motor used was the heads and we checked those. They are fine.

ramairws6

iTrader: (33)

Sorry to say.... but just because these injectors were new doesn't mean a thing.Too many times I've seen faulty or bad new parts and you waste your time looking at every other thing just because"they were new".Make sure you check this injector out like the others have stated.Traver

Inspector12

iTrader: (29)

Detination (sp?) was my guess although could be the other though.