Experts- need some serious help

[Camper]

Originally Posted by Matt @ FSP

I'll be handling some remote tuning on this to try to get it in line. Camper is an awesome guy and I just want his car to run correct.

Look at the narrowbands just drop out, so its going real on the lean side based upon the narrowbands and wideband reporting that Camper has told me. Any situation like that will induce knock of course.

This car can be tuned fine on GMVE/MAF, MAF only or VE/SD only... Just pick one. However as this tuner did, turning off the LTrims and putting it in MAF mode only is definitely not my choice with a blower setup without having multiple bypass valves at this level. You just won't dump the air fast enough to have a steady MAF curve.

Making adjustments on the GMVE in non-custom OS in HPTuners is actually very easy. Use Bluecat's EQ>VE program. The SD tunes take less time because you are only tuning a base VE table, not going back and forth between turning off the MAP, dialing in the GMVE and turning back on MAF...

thats why Im sending my wife to your place

[Matt @ FSP]

Originally Posted by Unreal

Canuk, he has a wideband just not hooked into hptuners.

Camper, if it isn't fixed by Sunday bring it over or I'm coming to you.

I found a picture of Unreal...

He's a real ...

[Unreal]

Tuna? I love tuna.

[Matt @ FSP]

Originally Posted by Unreal

Tuna? I love tuna.

Yes you Toona....

[stevieturbo]

Originally Posted by Camper

Dude, my blower sounds like a jet airplane. I can't hear my motor let alone something that sounds off..

That's why any sensible tuner/technician would use a stethoscope. Dont these guys ever have to diagnose problems ?

That's just basic stuff, not rocket science. You can hear the engine in very great detail, and you'll hear detonation or anything remotely like it far better than any knock sensor ( assuming your hearing is good )

[realcanuk]

Originally Posted by stevieturbo

That's why any sensible tuner/technician would use a stethoscope. Dont these guys ever have to diagnose problems ?

That's just basic stuff, not rocket science. You can hear the engine in very great detail, and you'll hear detonation or anything remotely like it far better than any knock sensor ( assuming your hearing is good )

\

Actually any sensible tuner would use a knock box on the dyno. With the blowers and exhausts most of these cars have, you wont hear much without it.

[Matt @ FSP]

Originally Posted by realcanuk

\

Actually any sensible tuner would use a knock box on the dyno. With the blowers and exhausts most of these cars have, you wont hear much without it.

Yes any diagnostic equipment you can use is a huge plus. However, after doing this for so many years you also get a keen ear to anything going on, surprised I still have it but my hearing is awesome 12 years later...

[stevieturbo]

Originally Posted by realcanuk

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Actually any sensible tuner would use a knock box on the dyno. With the blowers and exhausts most of these cars have, you wont hear much without it.

And it is those very people who struggle to diagnose problems, because they think technology will do it for them. It would be foolish to rely on a knock sensor, when you already know it is detecting false knock.


Get someone with actual experience solving problems

[JANNETTYRACING]

Originally Posted by Camper

nevermind found it

You found the Problem?

[Rhino79]

Put the car in power enrichment earlier, I'd bet the problem goes away. I see this from time to time on some na setups with headwork and fast manifolds. Depends on the engine setup really, but at 108 kpa like in the pic you showed, id have it dipping into pe mode.

[Camper]

Originally Posted by JANNETTYRACING

You found the Problem?

It appears it was all in the tune as Matt rewrote my tune and we datalogged and made adjustments for over 2 hours last night. We have a slight concern my valves are hanging open due to incorrect pushrod length but we will continue datalogging today and I'll measure pushrods just to be safe.

pushrods are currently a 7.65, I was concerned that was a little long for the application.

239/251; .624/.624 LSL cam and PRC 260cc heads, not milled

[JANNETTYRACING]

Originally Posted by Camper

It appears it was all in the tune as Matt rewrote my tune and we datalogged and made adjustments for over 2 hours last night. We have a slight concern my valves are hanging open due to incorrect pushrod length but we will continue datalogging today and I'll measure pushrods just to be safe.

pushrods are currently a 7.65, I was concerned that was a little long for the application.

239/251; .624/.624 LSL cam and PRC 260cc heads, not milled

Possible 7.400 is more typical

That is a 1/4 inch difference.

[Rhino79]

Holy preload!

[Camper]

Originally Posted by JANNETTYRACING

Possible 7.400 is more typical

That is a 1/4 inch difference.

in all my research the PRC 250/255/260 required somewhere in the 7.5-7.6 range. Its an aftermarket casting with the modified angle, deeper pockets and such.