It's been a year since the Tahoe's had boost under the hood. In November of '07 the snout broke off the forged GM HT383 crankshaft and set me back a bit. That engine was a GM HT383 shortblock with Edelbrock E-Tec 200 heads, Crower 00401LM cam (214/220, 114º .51") 1.6:1 Roller rockers, 62# Injectors, Vortec marine intake manifold, 2-bar tuned, long-tube headers and dual 3" exhaust. It had a 10.5" converter with 3800RPM-RPM stall speed into a built 4L80-E trans with a Gear Vendors overdrive and then to a 10.5" 14-bolt rear end with Eaton Posi. Boost came from a heavily modified Whipple Vortec 5.7 kit upgraded with the W140AX compressor - space for which was made by replacing the OEM vacuum brake booster with hydroboost. It had a 80mm throttle body. The compressor bracket outlet was modified to connect to a large air-to-water intercooler that I fabricated the mounting and plumbing for.
Despite weighing 5800 pounds even then with the smallblock, this was by far the funnest thing to drive I've ever been in. I miss the power, as I knew I would when I decided last November to start over with the Vortec 454. I acquired two used ones, the better of which went into the truck and the other went on the stand for mockup. I've got even more ambitious plans for this. To make 9psi with the 383 I had to run a 2.5" pulley and was redlining the compressor at the top of the RPM range. Making RPM in the tens of thousands in the supercharger with such a small pulley resulted in lots of belt-shredding, so from that experience I've picked up some insight I intend to apply to this next project. The bigblock is getting a 3.3L compressor and an 8-rib dedicated drive belt located on a pulley between the balancer and OEM 6-rib pulley. The supercharger itself will go on the passenger side. The mock-up 454 on the stand will probably a stroker kit, Trickflow heads, cam, rockers, etc. The project is still mostly conceptual, but I've got some photos and videos from when the 383 was running it's best (right before I broke it!)
Complete:
Heat Exchanger:
http://bertok.us/pics/w140AX/coolers.JPG
Mock-up before TIG:
http://bertok.us/pics/ic_plumbing3.jpg
Bypass Detail:
http://bertok.us/pics/bypass1.jpg
More Mock-up:
http://bertok.us/pics/plumbing3.jpg
IAT Relocation:
http://bertok.us/pics/iat.jpg
VIDEOS:
The tires on the truck at this time were 305mm wide Nittos. Street tires could not hook up from a dig. Ever!
http://bertok.us/pics/traction.mpg
For this one I've got M&H drag radials on it and warmed up. (P.S. - filming and driving is sorts awkward at the same time...)
http://bertok.us/pics/0-120.mpg
The rear brakes on the 14-bolt are stronger than stock, but not stronger than BOOST: (Toyos on in this vid)
http://bertok.us/pics/burnout5.mpg
This one's just some revving with the cats off, loud as hell, but fun:
http://bertok.us/pics/OpenHeaders.avi
This was the end of the 383...
So, now I've got this Vortec 454 in it...
It runs comparatively lethargic like this for now...
http://bertok.us/pics/454WOT.mpg
But, I've got THIS ONE on the stand in the garage awaiting some attention:
http://bertok.us/pics/altbracket.jpg
EDIT: Thanks Mike for finding me this alternator relocation bracket - it saved me HOURS!
That about covers the last three years or so. 2009 is looking good...