Silverado Vortec 8100 8.1 Backfire Diagnose, Updates and Upgrades 

@ronkirkham3410 Thank you for the kindness, I just take chances and show everyone what works. Believe me there are a lot of things I do that dont work!!! Again appreciate the kindness.

@user-um6qj6zt3n Thank you for the tip!

Glad I could help! Another viewer suggested using a vaccum gauge hooked to the intake manifold to verify the misfire is a valve/seat. The comment is on this vid, maybe try it out...

As I “have” two…

@ronkirkham3410 I have a tune video that has been used for years and other people use it to get a base tune for their 8.1. That video is free and you can email me for the full tune so I would start there. I dont know the specs on your build or the Raylar Cam so I cant really give you a power/drivability forecast. I have a head porting video for the 8.1 using a harbor freight die grinder so that is an inexpensive upgrade as long as you have a full weekend to dedicate to it. email me at mymusiconmyiphone@gmail.com and we can chat.

Downgrade would be a matter of opinion, you can get a flat tappet cam from Summit Racing for $100. $/HP has strong sway in my shop. Also Comp Cams 8.1 performance cams are backordered past May so its a great opportunity to break the roller convention. Thanks for the tip on the vacuum gauge! I was looking for a reason to upgrade parts so teardown was on the agenda.

where would i hook the vacuum gauge to on the intake, i need to perform this test

@@Tommy-bl2vm I am not really sure on the 8.1, I would have to look around. You could view the MAP sensor readings with HPTuners or a good scanner. Maybe t the MAP sensor with vacuum line to give readings to the MAP and vacuum gauge.

@kevinedwards7206 Yes, it will be fun once I get her going again!

Solid.

I have to pull the heads and inspect the damage then formulate a plan. Thanks for asking!

Ok so you haven't continued the tear down. Fair enough.

@@allenresinger9112 Correct, I have a Charger I am finishing paint and engine/trans tuning and I bought a police explorer ecoboost I have been engine/trans tuning and wrenching on. The 8.1 will be either the next video or 2nd.

Cant wait bud. Really enjoyed the first one. Like a good series that got cancelled. Lol

@@allenresinger9112 Thank you so much! That means a lot.

I had to replace mine too. Let me know if that repairs the misfire.

Replaced mine 02 sierra 3500. Was 5 year old fuel pump. Ran somewhat ok only to 1500 rpm then would backfire and fall flat on its face. Cure was a new pump. Got oriely lifetime replacement. I'm 66 y/o. I'll replace it one more time then someone else can have it. 134.000 on the clock.

Not sure, it never had an issue in that department. Good eye!

I love it when gauges work, most of the vehicles I have owned have something broken!