Its official my number 4 piston is shot. It showed 80% leakdown while all others were perfect. The compression ratio was 1-165 2-165 3-165 4-100

new motor time

mods were intake, catback exhaust, cobra h/e, 2.7 pulley at 19 lbs, 60lbers.

 

That sucks, have you pulled the head yet to check out the damage or just done the compression test

 

2.7 pulley at 19 lbs, 60lbers.

too much boost! haha

sorry to hear that bro.

 

just compression test, its 8 hours to pull the head off and 27 to rebuild not including fabbing.... its only 13 to drop a new one in... im just replacing it.

 

duh duh duh another one bites the dust........

Anyone know how that return fuel system project is coming?

 

How long have you been running it blown, did you notice a huge difference?

You and I got the Intense Stage 4 around the same time, now I'm starting to question my engine. I ran the 2.5"pulley with no cooling mods for a year straight, I know I know not good. Now i have a 2.7" on, runs like usual but I'm tired of worrying about it. I'm having mine checked, and will be downgrading to GM Stage 3.

Good Luck with the rebuild.

 

Damn Boost. So addictive....

 

this is fucked we need to sort this **** out. Good luck with the new motor

 

I ran it for a little over a year, i was getting retuned when it went but i believe it was due to the tune that was on it before hand wearing on it. Still dont know why it went, but I was going to down grade to a GM stage 2 and was talked out of it into just retuning. I should have just went to stage 2... i would downgrade if i were you. all a/f was good when it went too

I ran it for a little over a year, i was getting retuned when it went but i believe it was due to the tune that was on it before hand wearing on it. Still dont know why it went, but I was going to down grade to a GM stage 2 and was talked out of it into just retuning. I should have just went to stage 2... i would downgrade if i were you. all a/f was good when it went too

by the way this is exactly what happend to me.... it felt great until 8 months or so then it ran good, but i got weary about getting on it etc. im not sure why it just didnt feel right, now this... downgrade why u still can!

 

What was your afr when at wide open throttle? Im going from the 2.6 to a 2.7 in the next week.

 

sorry to hear it bud just do it yourself, its easy to do! i thought it was gonna be harder than it was!

 

i really dont have the time it took me 2 months just to get a compression check done. My job has me traveling alot etc.... its just going to sit while i save... not sure my exact a/f but it was in the green meaning not bad...

 

i'll be in ottawa this month some time Im sure, so i'll give ya a buzz

 

I did this after I put my 2.5 on. Without it, I get weird knock, with it, none.
This is very interesting.....I don't see it in your tune. The variable must have been a mechanical item. I know you didn't beat on it.

 

yea im guessing that mysterious ticking was something in the engine and not my cat/sway bar as it came back right when it was about to go.... it was probably caused by running the intense tune for a while =/

 

yes aeroforce, i was only receiving limited knock at wot, but once i had this ticking noise after about 3 months with the kit i RARELY got on it...

 

it was scanned but it was too late, and the next motor is staying stock

 

damn man... sorry to hear that, but from what I saw the intense tunes were pretty lean and ran way too much timing for pump gas. 21 degrees on a 2.5 pulley without meth = boom

 

Cooling mods FTW!

 

i run 23 * on 93 with no knock on my 2.5 pullied car... but i have every cooling mods besides meth.

 

same setup i was running when i popped #4.... intake/2.7"/60's

sorry to hear about your car.


edit: dont be so quick to blame the intese tunes guys, my car was custom dyno tuned with an 11.5:1 air fuel ratio, and still popped. not saying running the intense tune wasnt a contributing factor, but i see the 60# injectors and pullys smaller than 2.8" as the only constant factor in all these blown motors. i have only seen one ljs go that was running 42.5's and he blew 3 cylinders not just #4. im not on this forum often so are there more cars over here blowing up on the 42.5's or is it pretty much just the 60's?

 

im not blaming intense, it was just a bad combination all together. I wasnt running the intake on the intense tune though.

 

Sorry to be so naive, but could you guys just clarify a few things for us?

So would you consider the originally listed mods of intake, exhaust, 2.7" pulley, and 60# injectors as "dangerous?" These seem like fairly "light" mods to me, which many people here seem to be running. I know it's very difficult to guess, but what exactly do you think the risk is here? With those mods, how many miles until the motor goes?

Or (to the OP) would you say that the lean intense tune was more likely the cause?

What exactly causes the "blown motors" like this? Is it a too lean air-fuel ratio? Is it something to do with the larger injectors? Or is it just a bad tune (again - too lean, but wouldn't the larger injectors help remedy this?)

For those who want to run smaller pulleys, what supporting mods would best reduce these kinds of risks? Definitely some cooling mods, correct? It appears we'd need more than a heat exchanger, so maybe methanol/water injection? For more aggressive supporting mods, what would be needed? New pistons? Would anything else be needed, or are the pistons the source of the failure mostly?

Again, sorry for the simple post, but if any of you more knowledgable guys could help out with these questions, I think it'd really help out the community. Thanks in advance.

 

i believe it was the knock that was assocaited with the intense tune, i knew it was cookie cutter and is really my own fault. But i do not believe they should offer it and say it will work. B/c it does... for a while... just get a custom tune and you should be fine, if your going to mod heavily get meth/water injection.

 

Thanks bud, good luck with the new motor!