LSX454 swapped 95 BASS burb.

[folkenheath]

Something isn't making any sense Rick.

I've personally had it sitting parked with the key on and changed the park position, and watched the IAC move, that's how I test it.

Are you sure you haven't been downing too many beers at Beer Blvd or whatever your sign says?

 

[shady]

It may be there when it's off and key on. But that's not where it is when it's starting, after starting, or idling. It goes back to that position when I'm driving down the road. That's the only time I personally see that position, because I'm not looking at the handheld before I turn the key lol.

While watching it as it starts, it follows this chart. All of which are higher than the parked position.

So when they say it has to do with starting, really, Holley themselves are wrong. At least whoever actually wrote that part in the manual lol.

 

[shady]

I dropped the right hand side of that chart to around 35-40, dropped the hold time to 3sec, and the decay to 2.5, and that crazy high rpm start went away.

That was before I changed the parked position to 30.

I did read, on the Holley forum, that closing that parked position down will help with idle hang. Which I've been experiencing. Like I mentioned where the idle seems to stay high and I can cruise about 30 without touching the gas. Until I come to a stop. Where it goes back to normal.
All I did after changing that was drive across town back home though. So haven't really done much to test.

 

[folkenheath]

That chart is the parked position Rick(look at the top). The park position changes based on coolant temp for cold starts, hot starts, etc.

What other number are you changing that you believe is the parked position?

 

[folkenheath]

These are the other numbers..

Ramp down is how it ramps the engine back down to idle while driving and using the throttle.

Startup IAC is how long it holds the parked position chart setting, and how fast it ramps it down after hold during startup.

 

[shady]

Yeah I went to change it to 25 and seen that it said hold when I did.

I could have sworn an oath that it said parked position when I set that with the laptop.
Only 2 beers at that point.... Lol


Maybe I should had 4 I'd have read it right

 

[shady]

Current state of normal idle.

Had to raise idle to 780 because 700 was too low for the alt to keep up.

 

[folkenheath]

Looks right now.

 

[shady]

Starting is a lot smoother and less rpm too.

 

[shady]

I know my other LS's made odd noises under the hood compared to carb'd stuff.

But doesn't this sound like a diesel..?

It's made me worry since I started driving it, but it seems to be running and driving fine Oil still looks good too.

 

[folkenheath]

That does sound loud. Always does this? or only when cold? or when hot? At all RPMs?

Are the pushrods the correct length? Rocker arms stock?

What pistons did you use?

Hard to tell when not in person. I would use a stethoscope, or do the piece of wood trick to narrow it down.

 

[shady]

It always does it. Pushrods looked like new so I reused those, stock rockers,
Pistons are flat top forged with 2 valve reliefs, 10w-30 oil, can't really tell if it happens when higher rpm.
Sounds the loudest when over the engine in the middle, looking down at the intake.

I thought about the stethoscope yesterday, but didn't look for mine yet.

 

[shady]

Heard mainly at idle from in the truck.

 

[folkenheath]

Was the preload OK on the lifters with the stock pushrods and that cam?

How much piston to wall clearance was there with your pistons and bore?

See if it's louder on the valve cover, head, or block with a stethoscope, and each side. You can check the fuel rail but it sounds louder than any injector I've heard.

 

[shady]

Everything fit the description and felt like it said it should going by the LS rebuild book I bought.
And I my Machinist originally bored the block for hyperutectic, but he wanted my pistons, so he kept the engine till I got em in and then he used one to resize the bores.
No idea what the actual clearance was but he was telling me about having to make em slightly larger due to the forged pistons. He builds winning drag cars and most high HP engines in our area so I trust him lol.

 

[folkenheath]

Well forged pistons can have easily piston slap when cold, but if the bore is correct it usually goes away once they warm up.

 

[shady]

Yeah.. he was talking about that. Vid was taken at normal operating temp.

 

[folkenheath]

I'd go show it to him in person and see what he says.

 

[shady]

One thing I've heard from people is summits lifter wheels being stuck . When I started this it was making a high pitched sing for a little bit, then it came out of it. Like a minute or so.
Oil was primed prior to start up.
I couldn't tell exactly where the sound came from, thought it was belt or something at first. But it didn't sound like a belt really. Then it went away, so I moved on.
I've heard that that sing sound is indicative of the sticky roller.

 

[folkenheath]

Doesn't it sound like the frequency is multiple per revolution?

It doesn't sound like 1 cylinder or lifter, it sounds like all of them, but its just a video. In person is much easier to tell.