New Member to the Blown Motor Club!

[Prof]

sound like an elite club to be in, i believe ill pass...lol

What no guts? What is life without a little risk taking?

 

[eddie102870]

i took some risk years ago that im still paying for, should have them paid off in about two more years, then i can f*%# up again....lol

 

[Ram From Hell]

One might think I'd be somehow vindicated about pistons breaking on other FI systems due to my prior association with STS. Nothing could be farther from the truth (except perhaps if I said I had an extra large schlong).

I think the most credible investigative work done to date was done by Roe. He installed 10 O2 sensors on a test engine and found the engine going lean up front (#2 & #3 specifically) by more than a point. While a point may not inandofitself be a drastic issue, consider what those lean cylinders mean when tuning on the AVERAGE AFR for the engine (or each bank of cylinders). Then it can become a big issue. Under boost, this difference on those cylinders is not going to increase on a linear scale either. I believe that those that have had failures due to pistons breaking or burning have this to blame.

I also believe that the Roe SC is the best possible choice for FI based on this research. He refuses to make a side mount with his compressor as he will not boost the stock intake manifold, believing that it is a design flaw with the intake that is to blame for the errant lean-out problems. Notice that the GenIV engine has gone back to twin TB's and plenums like the GENI and GENII instakes! This must be a known issue!

There are of course other issues that have lead to engine failures (rod oiling, as mentioned above), but I'm betting if this is a blown piston issue, the stock intake may be to blame. While it's easy to say "it is all in the tune", if the tuner is not monitoring all 10 cylinders and adjusting the AFR for each when tuning, he can't compensate for the lean cylinders other than by making the whole tune pig rich. But of course in doing so, leaves tons of fuel on the table just because of a couple of lean cylinders.

Gentlemen, IMHO, we need an aftermarket intake manifold! Maybe someone can talk Roe into adapting his supercharger base for NA so it can be used for that or FI!:rock:

 

[Scrambler1]

Ok here is what we think happened. Gary installed the paxton and VEC and did all of the tuning. Everything was fine for quite some time, ~15,000 miles. Then the truck started having some wierd electrical issues, full lean on startup, eratic AFR. Took the truck to a dyno and it started going lean so we stopped. We then changed to the Paxton split second box with Gary's tune in it. Now way RICH, with a noticable burp. So I finally gave up and took it to Gary. He goes through all of the wiring and it still runs like shit... digs deeper and holed out piston.

Gary's speculation is that the VEC screwed up somehow, prob timing, he has had other problems with them. While in regular driving conditions my AF gauge showed everything normal, but from the dyno we know if was leaning out under full throttle. This was my daily driver so I damaged it sometime between losing the VEC and when I really discovered the problem on the dyno. Everything else was just a symptom.

 

[Scrambler1]

Ram from Hell's explanation may be the best I've heard for why the #3 goes out first.

Joe

 

[Silverback]

One might think I'd be somehow vindicated about pistons breaking on other FI systems due to my prior association with STS. Nothing could be farther from the truth (except perhaps if I said I had an extra large schlong).

I think the most credible investigative work done to date was done by Roe. He installed 10 O2 sensors on a test engine and found the engine going lean up front (#2 & #3 specifically) by more than a point. While a point may not inandofitself be a drastic issue, consider what those lean cylinders mean when tuning on the AVERAGE AFR for the engine (or each bank of cylinders). Then it can become a big issue. Under boost, this difference on those cylinders is not going to increase on a linear scale either. I believe that those that have had failures due to pistons breaking or burning have this to blame.

I also believe that the Roe SC is the best possible choice for FI based on this research. He refuses to make a side mount with his compressor as he will not boost the stock intake manifold, believing that it is a design flaw with the intake that is to blame for the errant lean-out problems. Notice that the GenIV engine has gone back to twin TB's and plenums like the GENI and GENII instakes! This must be a known issue!

There are of course other issues that have lead to engine failures (rod oiling, as mentioned above), but I'm betting if this is a blown piston issue, the stock intake may be to blame. While it's easy to say "it is all in the tune", if the tuner is not monitoring all 10 cylinders and adjusting the AFR for each when tuning, he can't compensate for the lean cylinders other than by making the whole tune pig rich. But of course in doing so, leaves tons of fuel on the table just because of a couple of lean cylinders.

Gentlemen, IMHO, we need an aftermarket intake manifold! Maybe someone can talk Roe into adapting his supercharger base for NA so it can be used for that or FI!:rock:

If I remember right, didn't Phil (BigAsp) also spin the #3 rod bearings both times his blew? I think that is the same time that Hennessey chimed in about the oiling problem.

 

[Ram From Hell]

If I remember right, didn't Phil (BigAsp) also spin the #3 rod bearings both times his blew? I think that is the same time that Hennessey chimed in about the oiling problem.

As I recall, at least the first failure was a broken piston, and the second failure was catastrophic (what exactly from, I do not remember).

 

[moparracing]

One might think I'd be somehow vindicated about pistons breaking on other FI systems due to my prior association with STS. Nothing could be farther from the truth (except perhaps if I said I had an extra large schlong).

I think the most credible investigative work done to date was done by Roe. He installed 10 O2 sensors on a test engine and found the engine going lean up front (#2 & #3 specifically) by more than a point. While a point may not inandofitself be a drastic issue, consider what those lean cylinders mean when tuning on the AVERAGE AFR for the engine (or each bank of cylinders). Then it can become a big issue. Under boost, this difference on those cylinders is not going to increase on a linear scale either. I believe that those that have had failures due to pistons breaking or burning have this to blame.

I also believe that the Roe SC is the best possible choice for FI based on this research. He refuses to make a side mount with his compressor as he will not boost the stock intake manifold, believing that it is a design flaw with the intake that is to blame for the errant lean-out problems. Notice that the GenIV engine has gone back to twin TB's and plenums like the GENI and GENII instakes! This must be a known issue!

There are of course other issues that have lead to engine failures (rod oiling, as mentioned above), but I'm betting if this is a blown piston issue, the stock intake may be to blame. While it's easy to say "it is all in the tune", if the tuner is not monitoring all 10 cylinders and adjusting the AFR for each when tuning, he can't compensate for the lean cylinders other than by making the whole tune pig rich. But of course in doing so, leaves tons of fuel on the table just because of a couple of lean cylinders.

Gentlemen, IMHO, we need an aftermarket intake manifold! Maybe someone can talk Roe into adapting his supercharger base for NA so it can be used for that or FI!:rock:

very interesting..........

 

[Nowwhat]

Whew.....blown motor = $$$$ and lots o' down time...sorry for the loss.....

Now...as far as which number you lose....I lost 8 & 9

the real problem here is that the stock pistons are PAPER thin.....

however FI doesn't necessarily mean Boom....Quicksilver has many o' mile on his paxton....Perhaps the new the Roe rocks but keep in mind the last generation Roe destroyed motors from a non-uniform distribution of the boost...ie cooked the rear 2 pistons....Let's see what happens after someone logs 12k miles on a Roe...

Nothing is going to save you if your VEC or split second takes a dump....but meth injection is a cheap insurance policy.....

As far as re-build.....how far down the rabbit hole do you wanna go...?

I sleeved my block and got a bit more displacement from it...balanced and blueprinted the motor...then all the beefed up goodies...pistons, rods, main caps, new Ti valves etc....

$$$ no object..???....STRIKERS.....:rock: ....

From what I read though...you are going FI and nitrous...if so....skip the $$$$$ heads as you can just up the shot

I am making 700 rwhp on stock heads and stock maifolds that power is MORE than enough to overwhelm street tires in any gear....

When I hit the track tomorrow...I will add any where from 100 - 200 rwhp via the bottle...I made 1 1000rwhp run before I blew up....and it was a joke..smoke show time at 100 mph in 3rd..without serious suspension mods 1000rwhp doesn't grab....

I don't know yet....but I am guessing 850ish rwhp is the sweet spot at the track....

 

[Scrambler1]

Yup, pretty much what I'm going to do. Not sure about sleeving yet what kind of $$ is that if you don't mind me asking? We'll see how bad it is inside once its all apart. Not doing strikers, just work on my stock heads. This is money I wasn't looking to spend anyway so if I'm going to spend another 3gs, I'll talk to Stinker about a new rear end so I can run 15's.

Still undecided on builder for motor. Arrow will bench dyno it but I have to ship it to them. Proline is not far from home so I can deliver, think they build the motors for Underground??? They come highly reccomended. Have to decide pretty soon though.

I had over 15,000 miles on my Paxton so considering stock internals and how hard I ran it, not too bad. Chock it up to bad luck. Goal is a reliable streetable motor. Will ad nitrous to get it where I want for the track.

Joe

 

[Nowwhat]

Yup, pretty much what I'm going to do. Not sure about sleeving yet what kind of $$ is that if you don't mind me asking? We'll see how bad it is inside once its all apart. Not doing strikers, just work on my stock heads. This is money I wasn't looking to spend anyway so if I'm going to spend another 3gs, I'll talk to Stinker about a new rear end so I can run 15's.

Still undecided on builder for motor. Arrow will bench dyno it but I have to ship it to them. Proline is not far from home so I can deliver, think they build the motors for Underground??? They come highly reccomended. Have to decide pretty soon though.

I had over 15,000 miles on my Paxton so considering stock internals and how hard I ran it, not too bad. Chock it up to bad luck. Goal is a reliable streetable motor. Will ad nitrous to get it where I want for the track.

Joe

when you settle on a builder they will walk you through what they think....Due to the amount of juice I plan on running....sleeving and nitrous specific pistons were needed....I don't have a cost for you.... ...but sleeving takes time.....for the $$$ having your builder run the motor in on a dyno is a great idea....