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6.2 vs 5.3?

Last night a buddy of mine pulled up next to me, brand new Laramie and said lets see what that thing can do.

Before the next stop light I was 2 car lengths ahead of him and still pushing. Granted I knew the 6.2 was fast but last night was the first time I truly stood on it and dam.
 
Just joined this forum and looking for some real world advice. I will be buying a Trailboss within the next week and was looking for some advice. My local dealer has several 6.2L but no 5.3L. Is it true that the 6.2 requires premium fuel? If so what happens when you just run regular non priming fuel?
Thanks for any insight you might have.
If you like power, get the 6.2 and put premium in it. This is probably the last generation of big v8's so splurge if you can afford it. On the other hand, the 5.3 is a perfectly adequate and reasonably fuel efficient option for any Silverado and runs on regular. You will not be happy with the 6.2 if you worry more about fuel economy and the abysmal future of fossil fuel prices.
 
Last night a buddy of mine pulled up next to me, brand new Laramie and said lets see what that thing can do.

Before the next stop light I was 2 car lengths ahead of him and still pushing. Granted I knew the 6.2 was fast but last night was the first time I truly stood on it and dam.
Hellz yeah. 6.2 is no joke!
 
Just joined this forum and looking for some real world advice. I will be buying a Trailboss within the next week and was looking for some advice. My local dealer has several 6.2L but no 5.3L. Is it true that the 6.2 requires premium fuel? If so what happens when you just run regular non priming fuel?
Thanks for any insight you might have.
Yes, you must run Premium fuel. I have the 6.2 and run 93 octane. You can google why you must run it in the engine. It is important to run with 6.2. You can experience knocking from the engine and potentially cause damage I have read.
 
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The keyword here is "recommended", not "required". Those saying it is "required" or that you "must" are spreading misinformation and is merely an opinion, but the fact is, you can use regular gas in the 6.2l Silverado.
 
The keyword here is "recommended", not "required". Those saying it is "required" or that you "must" are spreading misinformation and is merely an opinion, but the fact is, you can use regular gas in the 6.2l Silverado.
True. To get the advertised HP&TQ numbers, premium fuel is necessary.
It will run just fine on 87.
 
Mine runs much better on 93. At home 91 is as good as it gets so that's what I use. I have had to use 87 over the last year and when I did I went to OReillys and bought octane booster.
 
First off, there's no replacement for displacement, except boost. If you want the power, get the 6.2L, else the 5.3L is just fine.

The short of it all regarding "93 Octane Recommended";

The PCM has two timing tables. One for "Low" Octane (87) with less timing and one for "High" Octane (93, or 91, or 92, you get the point >/=91) with more timing.

If knock is detected, pull timing to match Low table, else use timing from High table. It'll do this periodically.

It all boils down to 4 things;
~Compression Ratio
~Timing
~Octane
~Temps

These newer engines to make more power, use higher compression. These aren't the Cast Iron giant Vortec's of yesteryear, they dissipate heat rather efficiently, and the newer computers are extremely advanced.

Older OBDI prom's had a single timing table, and used Speed Density rather than MAF for calculating Air/Fuel. These are far more advanced than the OBDII 0411 PCM module I rewired into my 94 S10 for MPFI to use a Turbo. These newer PCM's have different tables for different conditions. If low octane is used, the Knock sensor will detect this and cause Timing Retard (pulls timing) until it matches the Lower octane timing table. For a boosted high performance application, by the time this occurs....it's generally too late "Window Block Mod Initiated!"

The concept of using higher octane is to keep predetonation from occurring (ie Spark Knock/Ping). I'd also recommend a catch can for a DI Engine, that shit running through your engine will turn your 93 into 89 real quick depending on how bad you're sucking shit through.

Temps will also effect how well the octane actually works. Winter air is really cold, it's dense and allows for lower octane to be used. These lower temps keep predetonation from occuring. The density of the air is just going to read different according to the Oxygen Sensors and more fuel will be added, but the 87 Octane will perform just like 91+ Octane. Don't believe me, run 87 on a 45°F day, slap it on a dyno, do 3 pulls and record the timing used with HPTuners Pro (or similar). Then run 2 tanks of 93 Octane, go back on same temp day, and do 3 runs and record the timing used. Then come back and tell me I'm right.... because I already know the answer.

The TLDR is;
~Summer (>/=60°F day) 91+ Octane.
~Winter (<60°F day) 87 Octane is adequate, 91+ Octane if it makes you sleep at night.

P.S. steer clear of shitty gas, and if it's your only option, drop in a small bottle of something like Lucas Fuel Treatment first.
 
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You buy a truck with the 6.2 engine because you like the power it has, and it's a dandy. But then you run 87 fuel. To get all that the excellent 6.2has to offer and the reason you bought, why in the world would you not run 93 octane fuel?
I have a2020trail boss with a 5.3 10spd. It runs well. I also have a 2019 Camero with a 6.2 10 speed, I bought it for fun and would never run anything but 93 octane fuel.
Buy, each to his own.
 

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