A (hopefully) good 400 block. The guy that owned it before had it sitting in his garage after blowing a head gasket about 10k miles since a rebuild. It looks like I can reuse the crank and rods, and maybe the pistons depending on what I decide to do. This won't go into my current 'bird but I haven't decided where it's going to go yet.

My goals:

1) Budget motor.

2) Streetable.

3) 400hp.

4) Pass emissions. I need to research this a bit further. I know I have to pass an idle and 35mph test for HC and NOx. I'm not sure if I need to have EGR and all that stuff. Maybe some other people from Vancouver can let me know?

From what I've been reading, these goals seem reasonable.

I'm not sure what kind of compression I can run, I think I should probably start with this. Around here I can get up to 92 octane reliably. That means a max of what, 9.8:1 CR (depending on timing, etc)? This is on iron heads of course. I hear that Vortec heads can run a bit higher because of their improved chamber design. Is this BS?

So this is what I'm thinking:

Heads:
Vortec with new springs etc to handle a higher lift. This is what I'm leaning toward.
Iron Eagles 200cc with 72cc. This makes it easier to get a lower CR.
Any other ideas? I'd like to keep it cheap as possible.

Intake: Edelbrock Performer with EGR. Might be Vortec if I can use the heads.

Carb: 750 cfm. I haven't made up my mind here yet.

Cam: This is where I'm confused. Does engine size affect the powerband of a cam? I'd like to make power up to about 5500 rpm. I've read that means around 235 degrees @ 0.050, but does that only apply to a 350? I think it also depends on the flow of the heads, so which should I decide on first, cam or heads? I'll be using hydraulic lifters. I was thinking about using Rhoads lifters, are those worthwhile?

Whew, that was a lot of typing. Any suggestions, anything I'm forgetting?

 

Hey man,

1 horse per cube is not alot to ask from a sb 400.

If you have extra $, spring for the Iron Eagles since they come pretty much dressed with screw in studs/springs/retainers ect... Intakes will be much easier to find used & more selection, also RR will be easier to find used ect... get my drift?

But if you do go with the Vortecs, (very good head also) i would run a nice Performer RPM on it, with maybe a Comp XE268 (224/230 @.050, .477"/.480")or a little more radica lComp XE274 (230/236 @ .050", .487"/.490"). I personally love the Comp280H(230/230 @ .050, .480"/.480") on a mild 355 but it may fall a tad short for a 400sb.

The bigger the cubes, the more the compression, the milder the cam will act. Rhodes lifters will give you more vacuum & less duration/lift at a lower RPM which will create more low-end torque & throttle response. The downside to this is that they are quite noisy & sound like a solid cam. So if you can live with the noise, then you will gain some power down low.

Good Luck

 

Rhodes lifters WON"T be needed with either one of those comp cams. I'm running the xe268 in both my engines. 355 in 87 GTA, and xe268 in my 77 T/A 400 Pontiac. In the 77 im running stock converter w 350t/ 323 gears, doesn't sound neer as cammed as the 355 chevy. I think I'd go with the 274 and a 2100 stall in a 400 sbc. In a 3rd gen, if in a 2nd gen I'd go with a deeper gear. They are a tad heavier.

 

cp87GTA,

You should re-read his post. The only reason i mentioned RHOADS LIFTERS was because he asked about them & i simply wanted to point out their benefits & why people use them. I fully understand that YOU DONT HAVE TO use them if you don't want to.

 

I believe you said this was going to be your street motor. The 400 has an extremely deep and rich powerband, but those Iron Eagles, are not the things to pop for. They are too big for the powerband that I think that you want to make. They also have a combustion chamber that will promote detonation far more than the Vortechs. They are definately not a true upgrade!

You are asking vey little out of that 400. With some Vortechs, I would run a low (but high for 87 octane fuel) compression ratio. That way you can make up the cost in lost fuel milage, with the ease of easy pump gas: 87 octane.

I want 480 hp out of my 400 and it is not an un-streetable motor.

-

BTW- with the torque that you are going to put out with that motor, you will want to beef up the driveline. A- Increase the line pressure of your th-700 or B- Toss your T5 if you have a manual, in favor of something stronger.

 

Well I did read his post, and yours. I didn't say anything about having to use them. I said they won't be needed. Why would any one put rhodes lifters on a xe268 or 274? Defeating the purpose of the fast ramp cam. Both of those cams produce plenty of vaccum, for power acc.

 

Cool, thanks for the replies. (Wow, I go away for a few days and this is already buried on the 4th page.) I'll skip the Rhoads lifters, I just thought they were neat.

GreenProStreet, what is 'low' CR then (for a cast iron Vortec)? I read that the Vortec's are a good chamber design when combined with flat-tops. If I have to use dished piston to get my CR down then it won't be able to take advantage of the improved quench. I have no problem with running 92 octane, it's not too expensive around here.

I haven't measured deck height so that will come in to the equation as well, but it seems like 64cc chambers are too small to have a manageable CR (ie under 10 without running dished pistons).

I've been doing a bit more looking around, and maybe I'll go for the Sportsman II cast iron heads, those look good, and are almost within my budget.

 

bump...

 

By the time you work the Vortec heads over to the point that they will support that kind of power, you'll have about $900 in them. This would get you undercut valves ($200); spring pockets cut / guides milled off (absolutely essential) / cut for positive seals / screw-in studs ($150-200 labor, $100 parts); and real valve springs such as Comp 986 or other 1.45" outer diameter spring. For that price you could get Edelbrocks or some other far superior head.

I have a 400 with 186 (late double-hump) castings, 64cc, on my 400. I am running 12.5cc dish pistons, TRW/FM L2456F IIRC. This gives about 10.4:1 CR. I can get away with pump premium. I have been running this combo for about 10 years in this motor.

I used to have a XE274H in this motor. I loved it, it ran very strong, I recommend it highly. No vacuum problems whatsoever. I don't think a 268 would be enough. I would suggest 1.6 roller rockers with it, and definitely not th Rhoads or Crane "fast bleed" lifters. They look good on paper but I have never seen a single motor where they really made any improvement.

 

If you're going to use 64 cc heads on a 400, you'll
want to use dished pistons to get a decent cr.
Check out Keith Black KB168+.030 22cc D-cup pistons
With a "0 deck height" you'll have 9.8:1 cr. These are for
a 5.7" rod.
http://www.kb-silvolite.com/
Order them early as delivery can be an issue.
Don't bother with Rhoads Lifters. 400SBC's have loads of torque
and These lifters are not really designed for modern fast ramp
"Extreme" cam profiles. The noise is not worth it.

 

Ok, ok, no Vortecs!

Any guesses on horsepower you were/are getting? Premium in your area is 94 octane I'm guessing?

 

Hey, what is the actual deck hieght for those pistons? I have been searching everywhere to find a D dish piston like that! It would have to have a low dech hieght to get the 'quench' out of thep istons I need...

 

400 cid bored .030 over with a 350 crank!!!!!

 

i'd recomend:

comp cams x4270h grind or crane cams h272-2
kb 147 keith black pistons
0190 total seal rings
12497624 gm connecting rods
cylinder heads from an 87 to newer L98 (cast iron)
5703 edelbrock valve springs
3706 edelbrock intake
9974 edelbrock carb
sum-141506 summit racing rocker arms
sum-g6400 pushrods
12555283 gm oil pump (or equivalent)
12550042 oil pump pickup (or equivalent)
3998287 oil pump shaft
gm egr valve
headers with 3 inch random technology's cat and single 3 inch exhaust. that's a good list to start from to try and get what your looking for yet still pass your emissions.

 

Do whatever you want. The advice I've read on here has been from good to ignorant. I've been a part of and dynoed tested many different combos. The 400 is a great engine and Iron Eagles are great heads so are the Sportsman II's. Have dyno tested both on 400's. And don't waste your money on Vortecs. They are light weight casting and don't compare to a set of WP or Dart heads.

 

maybe it's just me, but i don't see where buying aftermarket heads were part of a budget build up except in magazine's. a set of ported L98 heads would suffice for what he wants to do.