Skyline Detonating On Dyno

[GotsWapan]

So my cars at the tuners getting the new GTX3076R put on with nismo 740cc injectors and exhaust. Its got a rebuilt bottom end with a re-co'd head. Its already got plenty of supporting mods such as Bosch 044 fuel pump, FMIC, Wolf 3D v4. Rang them up today to see how things are coming along and they say the cars detonating in the top end and they're not sure why.

So they asked me what kind of fuel I put in it. I put in a fresh near full tank of Caltex 98 right before I took it to them. They seem to think that may be the problem as Caltex runs a different blend of ethanol, possibly?

So they're going to drain the caltex and try BP ultimate tomorrow.

Can I get some input please, this is kind of worrying me and I'm questioning they're abilities.

[skylinecouple]

Let them check the fuel 1st then go from there. Did they mention the power it was making ? If around 270-280 at 18lbs it would seem about right. But if all goes according to plan there should be 290rwkws there. If the head was shaved I hope you used a 1.2 0r 1.6mm head gasket.

[R31Nismoid]

They seem to think that may be the problem as Caltex runs a different blend of ethanol, possibly?

Huh?

BP Ultimate has no ethanol in it. Nor does Caltex 98 (Vortex 98).

[GotsWapan]

I'm only quoting what they said. They're weren't 100% sure with what the mixture is.

[The Dan]

Let them check the fuel 1st then go from there. Did they mention the power it was making ? If around 270-280 at 18lbs it would seem about right. But if all goes according to plan there should be 290rwkws there. If the head was shaved I hope you used a 1.2 0r 1.6mm head gasket.

So you add 0.2-0.6mm for every 0.005" they take off the head?

[GotsWapan]

No they didn't mention the power it was making, I forgot to ask. The wastegate is set to 14 or 16psi. Its a standard headgasket, pretty sure

They built the motor in the hands of the previous owner so i assumed they would of known what they were doing. I hope so anyway.

[Bsa]

Ask them to test it first hope they are paying for it.

[PSI086]

It isn't suffering from timing jitter at all is it. They will detonate when the timing wanders and advances it too far

[Don Dada]

Maybe the set up is just maxed for the given boost setting. Without power and boost figures i'm afraid no one will be able to give any worthwhile advice

What a/r turbine btw? Std exh mani? External gate?

[GotsWapan]

It's apparently running zero degrees timing. It's internal wastegate on the standard low mount manifold with the .82 housing. Shouldn't be pushing anymore than 16psi, max at the moment

[TiTAN]

it could very well be a shit batch of fuel. its an easy and cheap thing to test.

[GotsWapan]

All odds must of been against me then if it is the fuel because I don't come to Melbourne often

[DVS JEZ]

Is the base timing set correctly?

[GotsWapan]

I assume it should be, they're professionals, they should know what they're doing.

They didn't have time to try it today. They put fresh BP in but no time to tune it. Updates tomorrow.

[WMDC35]

are they familiar with rb and turbos? sounds bad they have no pointers on why it's detonating? o44 & 740s should have plenty of fuel, maybe try somewhere else before they run out of det. time?

Edited May 17, 2012 by WMDC35

[privatealpha]

There is no ethanol in Caltex 98.

Its a perfectly fine fuel to use, its essentially the same fuel as Shell 98

[NoFigJamHere]

I assume it should be, they're professionals, they should know what they're doing.

They didn't have time to try it today. They put fresh BP in but no time to tune it. Updates tomorrow.

You need to get your car outta that shop ASAP before they knock the bearings out of it (if it hasnt already) or worse... detonating in the top end = big trouble!! Its also the hardest to hear/detect so if they're certain thats whats happening i would be really concerned if i was you... To say they dont know why its detonating is reason enough for any person to question there ability. You need to ask questions like How timing have they put in at the point of det? What are the lambda readings at that point? If those questions arnt answered quickly and confidently then its obvious they dont know what they're doing.

[Rolls]

Is it down on power? drop the exhaust in case of a blockage, tell them if they can't figure it out you'll go elsewhere, that is why you are paying them...

[GotsWapan]

It's sabbadin automotive if people are wondering. I tried to get into JPC but they were being lazy, arrogant regards. Customer service was the worst I've seen.

The tuners pulled the intercooler off and found oil in the bottom, so pretty sure the seals in the old turbo are stuffed. Cooler is getting sent away Monday to get cleaned. Hopefully fixes my issues.

[DVS JEZ]

Its more than likely just oil from the cam cover breathers. U may need a catch can to help prevent it filling up the cooler. Most cars will have oil in the cooler.

Is it blowing any blue smoke?

Is the cam timing and base ignition timing correct?

What intake pipe are u running to the turbo?