My Motor Is Broken

[IH8TOADS]

I have heard of one confirmed report of an XR8, 5.4L motor dying. It was standard and from what I hear the rod or piston somehow exited the motor quite violently. Warranty wasnt paid too...driver apparently punished the motor beyond its capabilities.

[Romulus]

unfortunatly it was always going to happen. Hence why I originally capped power in the first place @ 330 rwkw's. WHen Jas fitted the zorst we where in the back of our mids saying, this isnt going to last long. I mean seriously, stock engines just cant sustain that sort of power.

I told jas that it wouldnt live at that power but like he said he is getting a stronger bottom end anyways so the plan was to fit the zorst he go on holidays and when he got back biuld the bottom end... Unfortunalty the engine didnt last that long. It was running very safe afr's.. Its just alot of power for a stock motor to have.. It only pinged once in our testing and when it did ping it was after we had decided it must have a problem.

What I find a little hard to to understand is, the pistsons arent really a week link... the rods are.... why the pistons let go is beyond me... maybe had a fault to begin with... I dont know.. but I am looking forward to see it being pulled down to inspect it.

<{POST_SNAPBACK}>

This might help explain why the engine let go Simon.

Check out this link:

http://www.airpowersystems.com.au/falcon/plenum/plenum.htm

It's not a plug for APS, but it does make a lot of sense. Especially considering #'s 4, 5 and 6 cylinder suffered damage, perhaps indicating a lean condition. I doubt the engine is that weak that only half of it let go. There must be an underlying issue.

Unless injectors are trimmed for each cylinder I can see how youny's engine blew. His car is the 2nd car with the Nizpro inlet kit that I know has blown an engine.

Edited 23/11/05 09:55 AM by M6 XR6T

[F6 RAPID]

I have a Nizpro kit on my F6 and I purchased it knowing that these guys should know what they are doing.

IMHO, if the manifold is pressurised (any positive pressure), then it cannot be forced into the cylinder until the inlet valves open. So it is largely irrelevant where the air is being forced in from (eg the front of the manifold a-la Nizpro or the middle a-la APS) as the pressure in the manifold is the pressure in the manifold regardless of where it comes in....................

I have taken boost readings on a boost gauge from both the front of my manifold and from the extreme rear of it. Exactly the same at both ends so methinks I may have something here....

[bcl]

Unless injectors are trimmed for each cylinder I can see how youny's engine blew. His car is the 2nd car with the Nizpro inlet kit that I know has blown an engine.

<{POST_SNAPBACK}>

Are you predicting problems for my 1000 HP motor?

Many high performance motors use front entry plenums.

APS posted that article to undermine Nizpro at the time, but I don't think they ever released that kit, and even with the APS design there is not equal distribution of air to all 6 cylinders.

All of the blown engines I've read about have been rods rather than pistons.

At the power levels that youngy is running the manifold won't be an issue.... tuning is far more of an issue.

The other important factor is that the inlet system BEFORE the plenum must flow the air required. Say in my case with around 600rwkw I've upgraded to 5" inlet piping and thicker IC to provide the air flow required.

Brian

[Xtreme F6]

well I can say that at the time of us checking youngys engine it was stilll running 12.0's afr's and wasnt doing anything it shouldnt except turn the tyres ALOT. I have since been told of a dead stock xr6T doing the exact same thing. I dont know yet and have been waiting for a phone call from youngy regarding the stripping down of it.

[Xtreme F6]

Unless injectors are trimmed for each cylinder I can see how youny's engine blew. His car is the 2nd car with the Nizpro inlet kit that I know has blown an engine.

Are you predicting problems for my 1000 HP motor?

Many high performance motors use front entry plenums.

APS posted that article to undermine Nizpro at the time, but I don't think they ever released that kit, and even with the APS design there is not equal distribution of air to all 6 cylinders.

All of the blown engines I've read about have been rods rather than pistons.

At the power levels that youngy is running the manifold won't be an issue.... tuning is far more of an issue.

The other important factor is that the inlet system BEFORE the plenum must flow the air required. Say in my case with around 600rwkw I've upgraded to 5" inlet piping and thicker IC to provide the air flow required.

Brian

my cars been running the nizpr gear and has been running upwards of 400 rwkw's but is mostly tuned around the 370 rwkw mark for daily duties and its done 8000 kms like this. No problems what so ever and I have no issues with the gear supplied by nizpro. I believe its fine.

[bcl]

well I can say that at the time of us checking youngys engine it was stilll running 12.0's afr's and wasnt doing anything it shouldnt except turn the tyres ALOT. I have since been told of a dead stock xr6T doing the exact same thing. I dont know yet and have been waiting for a phone call from youngy regarding the stripping down of it.

<{POST_SNAPBACK}>

Yes, best to strip it down and get a diagnosis.

Brian

[Romulus]

Unless injectors are trimmed for each cylinder I can see how youny's engine blew. His car is the 2nd car with the Nizpro inlet kit that I know has blown an engine.

<{POST_SNAPBACK}>

Are you predicting problems for my 1000 HP motor?

Many high performance motors use front entry plenums.

APS posted that article to undermine Nizpro at the time, but I don't think they ever released that kit, and even with the APS design there is not equal distribution of air to all 6 cylinders.

All of the blown engines I've read about have been rods rather than pistons.

At the power levels that youngy is running the manifold won't be an issue.... tuning is far more of an issue.

The other important factor is that the inlet system BEFORE the plenum must flow the air required. Say in my case with around 600rwkw I've upgraded to 5" inlet piping and thicker IC to provide the air flow required.

Brian

<{POST_SNAPBACK}>

Hey, I'm only reading stuff from the APS site and wondering if this may be the cause of the problem. Sounds like it isn't however.

Personally, I wonder how APS were able to draw the conclusion it did without thorough testing eg pyro and O2 sensor in each exhaust port monitoring what was going on during their testing. Reading between the lines I suspect they didn't; otherwise they would have made mention of it.

[Romulus]

well I can say that at the time of us checking youngys engine it was stilll running 12.0's afr's and wasnt doing anything it shouldnt except turn the tyres ALOT. I have since been told of a dead stock xr6T doing the exact same thing. I dont know yet and have been waiting for a phone call from youngy regarding the stripping down of it.

<{POST_SNAPBACK}>

That contradicts youngy's statement in post #6

"well it's all my own fault really. We never had time for a retune after my full 4in exhaust. Before that with the standard exhaust it ran 332rwkw with 15psi boost but a safe guess is that with the new zorst it was running approx 18 to 20psi boost on the same tune and at least 370rwkw"

So he didn't have it retuned after fitting the new exhaust. What boost was it running with the new exhaust? How was the 370rwkw power output measured?

I know after having done my valve springs and installation of new actuator assembly late last week, and the rest of the exhaust getting done early next week, no way will I go hard on the car without putting it on the dyno and recording what's going on. I've already had to adjust most of the turbocharger wastegate controls to stop boost creeping over 4000rpm.

Will be interesting to see what the damage to his motor was.

[IH8TOADS]

M6's APS link does makes some sense, but I know of GTR's in Perth with 400+awhp (one had close to 600awhp) with intakes similar to Nizpros and these never had problems. Its a big assumption to think that plenium design has trashed youngy's engine. Having a faulty bottom end myself straight from the factory makes me think that it is highly possible that youngy's engine simply had a weak point........who knows!!!! We could put cartons on this!!!!!