421ci SBC High Boost/E85/Blower/N2O Project

[DeltaT]

Finally got the wedding out of the way, now I can start working on my dream project.

I had a medium-boost 434 planned and actually had the short block ready but got enough feedback on my original choice of piston (too high a ring pack for higher boost) that I decided to sell the entire Motown shortblock and start again. Funny how moving the rings down 1/8" can affect decisions throughout the entire bottom end.

This time I started with a Dart Little M block, and worked with Howards Cams on a rotating assembly good to at least 1200HP.

Some initial pictures:
Custom JE Forged Pistons, with Tuff Skirt and Ceramic coatings, Tool Steel Pins:
https://static1.pt-content.com/images/pt/2010/04/new_421_customje_blowerpiston_mini-1.jpg

Howards Cams Forged Billet Rods with L-19 capscrews:
https://static1.pt-content.com/images/pt/2010/04/new_421_howardscrank_forgedbilletrod_min-1.jpg

Howards Cams American-Forged 4340 Crank, with Big Block Snout and double keyways for a hefty blower drive:
https://static1.pt-content.com/images/noimg.gif

Some top end shots (some of you have already seen these):

New AFR 235cc fully CNC'd heads, Inconel Exhaust Valves, 700# Solid Roller Pacalloy Springs:
https://static1.pt-content.com/images/pt/2009/10/afr_235cc_endlogo_mini-1.jpg

Intake port shot:
https://static1.pt-content.com/images/pt/2009/10/afr_235cc_intake_mini-1.jpg

Mock-up with the T&D Shaft Rockers (1.7Int/1.8Exh):
https://static1.pt-content.com/images/pt/2009/10/afr_235cc_exhaustside_mini-1.jpg

Here's the finish-machined Dart Little M block:
https://static1.pt-content.com/images/noimg.gif

4.155" bore, 3.875" stroke for the 421ci:
https://static1.pt-content.com/images/noimg.gif

I went with the billet steel maincaps on this one. The inner bolts will be replaced with ARP mainstuds:
https://static1.pt-content.com/images/pt/2010/04/new_421_dartlittlem_steelmains2_mini-1.jpg

Next - a thorough cleaning for everything, then I'll start test fitting stuff and file-fitting the Hellfire ring set.

More pix to follow.

Jim

[DFRESH]

Dude, glad you got that wedding thing out of the way--LOL.

Good luck with the motor--keep us posted.

Doug

[LSx_88_Ciera]

You got some nice hardware there. What style blower you going to use?
Just an fyi it is NO². If curious to make the small 2 hold alt and press 0178.

[Jims78elky]

Looks really good Jim..those new AFR's should do the job for you!

Keep up the great work!


-Jim

[DeltaT]

I am going to fab up some quick-change bracketry so I can switch back and forth between a Vortech YSi centrifugal head unit and a Whipple 3.3l twinscrew, hopefully in under 1.5 hours. The Vortech is generally better for autocross and road racing where the Whipple is too torquey off idle. It's yet to be determined which will be more fun on the street. I can only stuff a 275/40/17 drag radial under the rear wheelwells, so traction will be a concern. I'll probably have to go to a numerically lower gearset from the current 3.73's, maybe a 3.23 or even 3.08.

The Vortech is going on first as it is closest to my current setup which is a 383/T-trim.

I have high expectations of the AFR heads, based on their flows and some early reports coming in. Not too many forced induction applications yet but the one turbo report Tony Mamo cites is quite promising.

NO² is nitrogen dioxide. N²O is nitrous oxide :enguard:

I'll post some more pictures tonight - both blowers, the modified single plane and anything else I can dig up. I haven't unwrapped the tool steel pins yet, so I don't know if they are anything visually interesting.

Jim

[LSx_88_Ciera]

:hand:
Always thought it was the other way around for some reason. I guess I thought that due to the power increase,
and thinking it would be *3 times as much oxygen as there is at sea level instead of *1.5.

Sounds like a really cool setup.

[shmoov69]

Niiiice stuff man! Looks like you will have some solid power with room to grow! Lol.

[shmoov69]

Double post

[turbo kid]

Any more info or photo up dates on the build?

[DeltaT]

Here's a few more I snapped last night:

New modified Hamburger Valvecovers. I added a -10 fitting above the stock baffles for venting, added a good-sized filler on a standoff, and beadblasted them in prep for coating:

https://static1.pt-content.com/images/noimg.gif

Here's the modified Motown Single Plane - fully ported and port-matched, this will now flow enough air in all ports to support the head. I also cut apart a NOS Big Shot Plate to make a spraybar that could be embedded in the manifold. I needed to do this to retain the stock, flat hood for the visual sleeper look:

https://static1.pt-content.com/images/noimg.gif

Closeup of the spraybar. There is masking tape covering the spraybars until everything is done. After final work on the manifold, I will have it coated (probably clear), then epoxy in the spraybar and give the top of the manifold a quick flushcut:

https://static1.pt-content.com/images/pt/2010/04/new_421_embedded_nos_bigshotplate_mini-1.jpg

More later today.

Jim