TXSZ66AVLANCHE

iTrader: (7)

SSmikeSS

iTrader: (3)

Exactly.
I was thinking $6 a week when I drove my truck daily.



There's always the E85 question bouncing around. I still don't understand it though. I still have a lot of reading to do.

topher67

The truck has every external motor bolt ons, CAI, e-fans, UDP, P&P TB, TB spacer, LT's , 3inch true dual with x pipe.

9.49:1 compression

Dyno runs All 87 octane, 20's 30" LTX, Texas 60ish degrees that day

CAI, muffler, stock tune: 223rwhp 267rwtq

Same above but dyno tune: 248rwhp 289rwtq

All mods 75ish degrees : 274rwhp 342rwtq

16-18 city 22-24 highway on 87 octane

No knocks or idle issues, the truck runs smooth, and pulls like a ****

Just wanting to get some more opinions and feed back about these results with 87 and how the heads/10:1 would effect my current results

My father and I have a 67 camaro with a 327 11.5:1 runs awesome on 93 octane

AKlowriderZ71

iTrader: (22)

Hmmm, that highway MPG is way too high. You've obviously done something wrong.

ak2007r6

iTrader: (1)

Wife always gets on me for fueling up with premium and wonders why I don't just use 87 to save money. It's not that big of a difference, it's better for if you are tuned and especially if you are boosted. I just wish we had better than 90 from the pump up here.
+1

topher67

3:42 rear end that's why!

1 Fill up till it clicks

2 set the odometer to zero

3 Drive till empty on texas to kentucky trip

3 take 550 miles, at 75mph, and divide it by 23 gallons

550/23=23.9

This has been accurate 7-8 times.

midevil1

iTrader: (17)

if you gotta save 5 bucks every time you fill up. You need to put a cam in it that will bleed off all the compression. My HD got 20.6 mpg's from Houston to Bowling Green twice. 3.73's and 5800lbs. It is lifted too..

AKlowriderZ71

iTrader: (22)

I was just joking around with you. I didn't doubt you for a second, just trying to be funny.

yurs78

I'm not an expert but last night I was searching and I found this:

5.3L LM7 Engine Build - Lucas 5W30 Oil - Truckin' Magazine

"Both the original 327ci small-block Chevy and modern 5.3L share similar displacements, yet they arrive at them differently. The 327 combined a 4.00-inch bore with a 3.25-inch stroke, while the 5.3L mixed a much smaller 3.779-inch bore with a larger 3.662-inch stroke. Unlike the LS1/LS2 and LS3, the small-bore 5.3L required a dedicated cylinder head and valve sizing to optimize flow. Trick Flow Specialties once again had just what we needed in the form of their Trick Flow GenX 205 cylinder heads. As the name implied, the GenX 205 heads offered 205 cc intake ports (flowing nearly 300 cfm), a 2.00/1.575 valve combination and small 58cc combustion chambers to ensure no loss of compression (factory 5.3L heads come with smaller chambers than typical LS1/LS2/LS6 heads). In addition to the tremendous flow potential, the GenX 205 heads featured a double valve spring....."

It sounds like to me that you'll be right around that 9.5:1 compression that you already have.

Love to hear the results, please keep us posted!

yurs78

Great results! I can't believe the amount of torque you've got, is this common? Do you have the graph, I'd really love to see it. I just bought a 5.3 yukon and I'm searching for the sweet spot of performance. I'm trying to get into this TQ range with as much off idle as possible, I don't care if it peaks at 5700RPM. Thanks again for the posts and good luck!