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Discussion Starter #1
Well, I feel as though I should re-introduce myself. I haven't been active on this site in a couple of years, mainly because I have beeen tinkering around with a turbocharged 4-banger for a while...don't worry, there's still a big block and a couple of small blocks in the family (79 Caddy and 78 GMC 4x4). So with introductions out of the way, I turn my attention to the 78 GMC...currently equipped with a mild 350. Everything was going well until I wiped several lobes off the cam over the course of 2 years/4000 miles of driving.

That brings me to today. I acquired a 2 bolt 400 block and crank that I intend to build for the truck. The truck is a 4x4 with a 12 bolt rear, 4.11 gears, and 32" tires. It will be bolted up to a TH400 with a 2400 stall.

The purpose of the truck is a hardware store runner (not a daily driver) that I would like to occasionally run at the track (3-4 times a year), surprise a couple of street cars, and turn a maximum of 6000 rpms.

Here's the setup I'm proposing...let me know if I am overlooking something for my intended purpose(s).

400 SBC bored .030 (done)
400 Crank machined at .010/.010 (done)
Speed Pro Flat top hyper pistons
5.7" con rods (haven't decided on mfr) clearanced for 400
Dart Iron Eagle 200cc Intake, 72cc combustion---shooting for 9.5:1 (drilled for steam holes of course) with screw in studs and guide plates
Lunati Voodoo hydraulic flat tappet (227/233 deg at .050) .489/.504 lift with 1.5 stamped rockers and hardened pushrods
Air Gap RPM intake
HEI Ignition (new)
Double roller timing set
400 flex/balancer
The entire reciprocating assembly will be balanced
New oil pump/bearings, etc.
New Main bolts, rod bolts, and head bolts
1-5/8" headers through 2-1/2" exhaust

I can't decide on a carb. I have a reworked quadrajet ready and a holley 600cfm vaccum sec. available, but I suspect the holley will be a little small.
Does the stock fuel pump have the capacity to handle this build?
Please give me your feedback on other things I am not considering as well as improvements to my setup...

Thanks guys, I look forward to being hit with plenty of wisdom/experience/sarcasm!

Shawn
 

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For the intended purpose of your truck I really dont see any thing that should be changed. I do think the holley will be on the small side though. Good luck
 

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It all looks pretty good. The only thing I would consider is a set of Vortec heads instead of the iron eagles. The dart heads are really nice, and they will provide room to grow and they will be more crack resistant than the vortecs. On the other hand, I think that the vortecs will make more low to mid range power, similar top end power and be cheaper. I had a set of the vortec heads on a 355 and loved them. You can get a set of the vortec heads modified to accept .525 lift, screw in studs, and guideplates for $425 from the site below ($340 with the use of press in studs and no guideplates)

Heads:
http://www.sdpc2000.com/catalog/2172/products/9063/Vortec-SB-Chevrolet-Cylinder-Head-w-Valve-Spring-Upgrade.htm

I would use a ~650 cfm carb

Here is a motor similar to the one that you are looking at except for with the vortec heads instead. The cam is almost identical.

428 hp @5000 RPM 525 ft lbs @ 3500 RPM 0ver 470 ft lbs from 2300-4700 RPM
http://www.chevyhiperformance.com/techarticles/148_0306_chevrolet_406_big_block_torque/
 

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Discussion Starter #4
Firestone
I hear you on the heads...I have that exact issue at home, which was the inspiration for the 400 build I am doing.

I am finding pairs of assembled Dart Iron Eagles for 729.00+80.00 shipped on ebay. That seems like a pretty good deal. Maybe they are building them with super cheap parts or doing shoddy head work?
 

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I would recomend going with 1.6:1 roller rockers. Compared to the rest of the package its not that much more of an investment and it will help those dart heads out a lot.
 

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72 Nova, 65 Rambler, 37 Chevy
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Chevtec said:
I am finding pairs of assembled Dart Iron Eagles for 729.00+80.00 shipped on ebay. That seems like a pretty good deal. Maybe they are building them with super cheap parts or doing shoddy head work?
Yea, Ive been looking at those too, anyone know the scoop on those? a set of iron eagle's from 180cc all the way up to 230cc's with your choice of plug position and chamber size for $810 shipped seems to good to be true...is it??? Low quality parts or cheap work on them? (also since im here has anyone took a look at the new summit aluminum heads for $995, they look nice .575 lift 200cc runner 64cc chamber all the goods...are they cheap imported, I hear problems of them have bad seats etc?)
 

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i dont think i would go with those heads, the old iron eagle heads are obsolite now with the introduction of the far more advanced iron eagle platinum heads, not that the old iron eagles weren't decent performers but the new platinums are GREAT!!!. i think that if i weren't to use the platinums then i would go with set of vortecs, and have guides cut down, new springs, bowl blend and port and polish.

i think the 600 would be too small, the q-jet should work or a 750 holley either vac sec or dp. i think that a set of with the platinum heads would be worth it for the extra flow, and IMHO the air-gap intake isn't worth the price, all you have to do is get a used RPM, notch the seperator plate about a 1/2" inch and use a 1" spacer and it performs better than the air-gap does.

i know this will start a fight but i have heard that the air-gap doesn't do well in cold weather. this is just what i have heard from others who have experiance with this intake, i have never used one. but i have seen the dyno test between a stock RPM vs Air-Gap (very little difference) and a modified RPM (modifications like i mentioned) vs Air-Gap and there still wasn't much difference but the modified RPM performed better
 
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