Motor went Boom!!! What happened?

[JDSfastGN]

Re: Hold On Just a Minute

Originally posted by ZR1TR
Before everyone gives him the kiss of death, it might be something simple. I wasn't running ungodly amounts of timing but something similar happened to me. Turned out to be broken rocker shaft. The scanmaster was showing like 19* of knock at 10 miles an hour. Car ran like crap and there was an awful knock that sounded like rod. The reason I mention this is because he said he never lost oil pressure, wasn't smoking (likely rule out headgasket). Hopefully your in the same boat I was.

Jonathan

yeah i agree completely, if it sounds like it coming from one valve cover alone, it probably isn't in the bottom of the motor (it could be) i had a friend break a valve spring and it was similar to what he desribed. Just pop that cover off and maybe that will be the prob. Always go for the easy stuff first, being he had good or no immediate change in oil pressure it sounds like its in the valve train to me. Good luck with it and keep us posted

 

[turbo2nr]

Those thin, hollow stock rocker shafts are also known for being a weak link. Don't make plans to rob a bank quite yet. 27-30psi on just alky? Dude, you are nutz!

Scott

 

[DCVING 6]

Whatever you do, you NEED bigger injectors. with a TE-60, 25psi you need a lot more fuel than the 40's can handle. What kind of duty cycle is it running at now?

 

[V8killR4U]

How can you tell what duty cycle its running? All I was really tuning by was knock, if i saw no knock, or a lil then i was like COOL. If i saw knock i got out of it and turned the boost back down. Like I said Ive had the cars for some years now and drove it a decent amount always 25 lbs of boost timing anywhere from 22-26. It wasnt knockin so i wasnt stoppin. WEll now i am. Im curious as to whats under the valve covers if any? But again what do you need to determine duty cycle on inj.

Originally posted by DCVING 6
Whatever you do, you NEED bigger injectors. with a TE-60, 25psi you need a lot more fuel than the 40's can handle. What kind of duty cycle is it running at now?

 

[JDSfastGN]

duty cycle is an option to view on some scan tools like direct scan and turbolink. But yeah hes right 40s aren't gonna go much further, i bet they are maxed out

 

[Sweet6]

Originally posted by KLHAMMETT
Not for nothing, But i think 26* timing is way out of line for alchy.especially on a stock block car. I was told not to attmept it on pure race fuel, Alchy helps, but it is not a replacement for race fuel with the boost and timing you are running, Guarentee the tops of the rod bearings are toast, well at this point all the bearings probably are

Most of the chip guys use 26 degrees on race chips. I know a guy that ran 30lbs with a PT54 with 30lbs and 26 degress on 116 with a stck block car. He never blew a headgasket. Who told you not to run more than 26 degress on a stock block car? I always 26 degrees and 22-24lbs with my Joe Lubrant chips. Never had a problem. Just curious.

 

[MSDGN]

I currently run 25-27 degrees on an Extender Extreme chip and 28 PSI boost and have been doing so for awhile...I do use only VP 116 though and ensure that it's tuned for zero knock...I would never try that on alcohol...

 

[Red Regal T]

I'm sold on the spun bearing myself. Of course, pull your valve covers to make sure you don't have a broken rocker or rocker shaft. If not get the hoist into action.

 

[turbo2nr]

ey captian, bring in the hoist! take it to the bow.

 

[Razor]

Well rule one dont run 25+ PSI when your tank says LOW..

I would drop the oil and let it settle.. then put it through a strainer... if a bunch of debris is in it.. its bearings.

You can make more power on boost than timing. And at high timing there is very little margin for error. Youd be better off running 29-30 PSI at 18-20 degrees.

At the track is one thing.. on the road/highway.. man thats another.

My vote is bearings.

 

[wiked87gn]

you said it yourself, how many years have you been running that motor like this????? with high boost these motors do get weak overtime you know. A friend had a similar problem like you it sounded really bad, turned out to be a loose cam sensor. also check the bolts on the convertor if one came loose could rattling around in there and sound does travel, take a hose put it to your hear and move it around in the car to see if you can pin point where the sound is coming from.

Originally posted by V8killR4U
WEll I was running the car for a few years like that. Timing that is and high boost 25lbs 26 degree no knock. Oh well back tot he drawing board

 

[Mark]

With stock heads and plenty of tuning, it's possible to run that much boost with 25+ degrees on alcohol and pump gas. I actually have some room left in my tune...

 

[V8killR4U]

Well I just pulled the valve covers on both sides and everything seems to be in order there. Any other easy stuff to check before the reality sets in and i come to the realization the motor will have to be pulled. I thinksomeone said the cam sensor? Where is this located and what does it look like so I can check this out. Any diagrams or anything available. DAMN, DAMN, DAMN, DAMN!

Thanks

 

[V8killR4U]

Oh yeah when i went to move the car to pukk the valve covers the car did start right up, but the oil pressure was pretty high when i started it 65-75. I just started it up and moved it, motor wasnt running for more than 1-2 minutes. Is oil pressure that high normal upon start up. Also I do recall before this incident that when cruising or putting a load on the car the oil pressure would read kinda high 55-65. Just thought that might help diagnose the problem better.

Thanks for all your help guys!

 

[V8killR4U]

One last thing too. A day before I had stopped at Murrays cam back out and startyed the car and there was a backfire, loud pop noise ive never heard before from the car. Just a lil more input.

 

[salvageV6]

What did it sound like when you moved it?

 

[V8killR4U]

Originally posted by salvageV6
What did it sound like when you moved it?

I mean it starts right up like it always has. Under idle you really cant hear anything. ALMOST anything, I really only notice this knocking sound when you press down on e the gas pedal. The more you rev it the more knocking and rattling. Did I mention the oil pressure is reading high now even at idle 60-65.

Thanks for the help guys. Im sure this will be a great learning experience.

 

[S2V6RACER]

The oil will tell the story. Cut open the filter. A detail not to be overlooked.

 

[V8killR4U]

This weekend i guess thats what ill be doig is pulling the oil pan.

 

[TurboBusa]

another thing, me and my friends ran into a flat lobe one time and could not figure it out till we took out the vlv covers and started the car we could see everything move up and down till we got to #3. i can't remember if it was the exhaust or intake but the lobe was done. That caused it to backfire at times too. just a thought. might be, might not be.