96-99 454 Vortec owners?

[xx_ED_xx]

Just to clear the air.

dietzster- Ok i saw you mention a cam i was wondering about running. I will be pulling my motor out tonite or tomorrow. I hurt a piston in mine doing the videos in my other post. the crane 168725.

and there is a few ways to build a 496 one is using the 454 block and stroker crank.

Or using a GEN VII 496 motor the bore is the same as 454 but the stroke is 4.370 and it is a tall deck motor. it is really similar to the GEN VI L29 motors. Stuff can still interchange. You can put early heads and distrubutor in it. With some modifications. Unfortunately for the heads that are on it. There is only one place that sells perfomance hard parts for them and thats raylar. Hence the original reason i didnt put a factory 496 in my truck.

[dietzster]

Sorry NODIH the vortec 454 and the 502 blocks (gen5 and gen6) are standard deck height (or short deck 9.8"), the vortec 8.1l is a tall deck 10.2" block, it has the same bore as a 454 but a longer stroke. I think Bankspowered was refferring to building a 496 (bored and stroked 454) I was just thinking instead of spending money on a stroker kit and a machine shop to buy a shortblock 502 and put on 454 heads, probably around the same price, I looked it up they are interchangeable and I think the vortec heads are 110 cc which makes the compression ratio 9.6:1 on the 502. I looked into building a 8.1l vortec shortblock and putting on 454 heads, it CAN be done with minor machining GM did it on their project coolside 2 truck. But I can't find the info on what machining needs to be done and don't have the bankroll to buy the parts and try it myself. So I gave that up, but a vortec 502 would be cool!!

[bankspowered98]

Vortec 502, I like the sound of that. Dietzster, you have a point. I beleive a search for a 502 is about to commence.

[dietzster]

Let me know what kind of prices you're finding, I work at a dealer, if I can get you a better price it might be worth a drive to you I want to see this happen! I don't know why I never thought of it earlier and waste a bunch of time trying to make an 8.1l work. This would be cool.

[N0DIH]

Thanks for the info on the decks!

Is the 496 techincally a Gen VII BB? I have seen one reference, but I also see refs that show it as a Gen VI.

[bankspowered98]

Yes, I am serious about the 502 project. I have been running across kits that would allow me to bore and stroke the 454 block to 489ci, 496ci, 498, or 505ci. Any ideas?? I am also wanting to spray N2O as well. What kit have your guys had experience with? I plan to go dyno tune the truck in the next month or so and would love to have everything on. I was thinking more along the lines of ZEX just for added control. I am only planning on spraying a 75 shot or so.

[xx_ED_xx]

Yes it is a GEN VII

The machine work invovled to put std heads is to fix 5 head bolt holes on each side. I had bought an 8.1 to put in my silverado originally. and I took a bunch of pictures. That and you got to remember everything on the 8.1 is metric. A guy locally has a 8.1 needing work for 500 bux so i was considering buying it since now i need to work on the 454. If i can get a replacement control board for my 300 gig hard drive I have alot of 8.1 info and pictures saved on it.

[N0DIH]

So thinking of the 496 now? Can you just use the 496 rotating assy in the 454 block and call it done? (ok, balance and such....)

[xx_ED_xx]

496 is a tall deck

[N0DIH]

Do the 496's use longer rods?

Seems like there should be pistons that are shorter comp height to allow the 496 crank to swing in the short deck block.

Just ideas to swing around...

Originally Posted by xx_ED_xx

496 is a tall deck

[dietzster]

I don't know about the rod length but the 8.1 crank won't fit in the 454 block it will have clearance issues with the block and the rods would probably contact the camshaft.

[xx_ED_xx]

rod length is 6.700
not sure about the crank, other then the sensor ring on it.

[jmcvay80]

I posted this over on the Performance exhaust section, I should've probably started here in the first place. What are the fellow big block owners running?


I'm looking into adding a catback single side exit to my 2000 GMC with a 454. I have found a couple of kits for my truck (Gibson and Flowmaster) and they both use 3" tubing. Looking at the same type of kits for 2001 and up trucks with 6.0 and 8.1 uses 3.5" (after the muffler). The truck is stock for now but plan to add some mods in the near future. Is it just me or does the 3" seem a little small for a 7.4 when the same kits for 5.3 or a 5.7 uses 3". Now the tubing going into the muffler is dual 3" (I think) and comes out 2.5". What do you guys think?

[bankspowered98]

Banks System runs full length headers, 3" duals back to the muffler and a single 3.5" out. Great design and one hell of a power upgrade.

[N0DIH]

I am thinking about how to do a better exhaust on my 99 K2500 454. Burb. Just took a trip and still there is a drone on the factory exhaust that seem load dependant, up in the 2300-2500 rpm range. Annoying. We just got back from Houston, around 2500 total for the trip. And the first part with a bad O2 murdering mpg. I went open loop and got it up into the high 13's low 14's, and high 12's in the Ozark Mountains on the scenic road, which is some really bad for mpg driving. We were loaded heavy, 8 people, luggage, and a cargo rack that had loaded coolers and stuff on it. Even felt heavy....

Originally Posted by bankspowered98

Banks System runs full length headers, 3" duals back to the muffler and a single 3.5" out. Great design and one hell of a power upgrade.

[jmcvay80]

I finally located the Banks Powerpack for our trucks and originally thought that the $1,400-$1,600 price was a little high. But since looking into headers at $600-$900 and stainless exhaust at $600-$700 its not seeming so bad. Jeremy, does the kit you have replace the cats? Not sure what I'm going to yet. The $1,600 is a little hard to swallow. I did find a Flowmaster catback kit for around $300 but it is alumninized.

[bankspowered98]

No, it utilizes the cats however i removed mine and picked up even more power. They know exactly what they are doing to be able to gain 80+ HP/TQ out of exhaust.

[bankspowered98]

Well, took the truck to the track the other night... didnt run too bad. My shift points were a bit high and I ran out of alky/meth injection after the second pass. Best pass was 13.3 at 108mph... Wheel hop was killing me. If anyone knows where I can get some decent traction bars please let me know.

[xx_ED_xx]

Calvert racing
cal trac bars, fixed my wheel hop completely

[bankspowered98]

awesome, thanks for the help. ill look into those later this evening.