Feels slow even after rebuild and rough idle

[Turbokat]

I'm just curious of what the acceleration should be with these trucks and what can cause them to run fine but just be a dog when you floor it.
Please note that the speedometer is in km/h

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This is how it was when i bought the parts truck. It was just a pig even WITH 4.10s!!

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This is after the rebuild and now its in the 2dr instead of the suburban. This is with 3.42s. Both have the 4l80e.
In this clip the speedo is off by about 9km/h slower. so when its at 100km/h is more like 110km/h.
I changed the distributor gear since it was really worn and got the timing really good but it didn't help at all. has brand new spark plugs and wires. I'm waiting for a spark tester i bought but it still hasn't arrived.

The truck has a brand new fuel filter, fuel lines and fuel pump. I am still using the old spider, MAP and MAF etc. so not a lot of sensors were changed. Water temp sensors are also reading correctly.
the engine also seems to run a little rough on idle. You can really both see the engine and feel the whole truck shaking like if it was a diesel

 

[L31MaxExpress]

Something seems up. I put a 4L80E in my Express conversion van when it still had 3.42 gears. I had a small Comp Xtreme 4x4 grind cam and 1.6 rockers at the time. Both of these were taken on a hot summer night.

Stock Tune

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Tuned

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Low fuel pressure or clogged cats can cause performance loss as can rocker arms that are not adjusted properly. All of the above as well as ignition or spider issues can cause a rough idle.

 

[big_mike]

Your still on a stock spider after a rebuild? Did you check FP leak down cause if you never opened the intake to replace gaskets during the rebuild then it could be leaking in the intake and you'd never know it. If everything around that is new I'd look there first. These stock spiders are known to go bad and cause all kinds of issues, including loss of power and rough operation.

 

[Overtime]

Put a timing light on it. See what you have at idle and at 4k rpm. Let us know the results.

 

[Lanny]

Put a timing light on it. See what you have at idle and at 4k rpm. Let us know the results.

Im pretty sure his crank pulley doesn't have any timing marks on it. Timing is changed with the computer on the vortecs as long as you're right on with your distributor gear.

 

[CCLB3500]

live data on scan tool will show degrees of timing.

 

[big_mike]

Im pretty sure his crank pulley doesn't have any timing marks on it. Timing is changed with the computer on the vortecs as long as you're right on with your distributor gear.

Yep, timing light will not read gotta use a scan tool with live data

 

[Ike98silverado]

Yep, timing light will not read gotta use a scan tool with live data

My truck shows 22-24dg timing at idle. 98 5.7 Silverado. Is that normal?

 

[Ike98silverado]

I'm just curious of what the acceleration should be with these trucks and what can cause them to run fine but just be a dog when you floor it.
Please note that the speedometer is in km/h

xc_hide_links_from_guests_guests_error_hide_media

This is how it was when i bought the parts truck. It was just a pig even WITH 4.10s!!

xc_hide_links_from_guests_guests_error_hide_media

This is after the rebuild and now its in the 2dr instead of the suburban. This is with 3.42s. Both have the 4l80e.
In this clip the speedo is off by about 9km/h slower. so when its at 100km/h is more like 110km/h.
I changed the distributor gear since it was really worn and got the timing really good but it didn't help at all. has brand new spark plugs and wires. I'm waiting for a spark tester i bought but it still hasn't arrived.

The truck has a brand new fuel filter, fuel lines and fuel pump. I am still using the old spider, MAP and MAF etc. so not a lot of sensors were changed. Water temp sensors are also reading correctly.
the engine also seems to run a little rough on idle. You can really both see the engine and feel the whole truck shaking like if it was a diesel

You can get the newer upgraded spider injectors for $239 right now. Just got one myself.

 

[Supercharged111]

Shaking is likely a misfire. Another guy recently had an issue where he'd set lifter preload too tight, could be the case here. Tried a compression test?