400 small block- ideas, advice?

I built a 377 stroker for my first '40 Chevy. I used 461 heads, a $125.00 set of cast Hi-duty brand pistons, and a 350 steel crank. It ran two years in the '40 till it was wrecked. After it was wrecked I was tired of seeing it sit in the corner. I pulled the 2x4 intake, and I put a C4B edlbrock intake on it with a 350hp 327 cam, and put it in my '68 impalla 4dr sedan. Talk about a sleeper!! About a year was enough though. I pulled the engine, junked the car and put the engine in a '78 Malibu. I ran it in the malibu for a year and a half and oil pressure started going down so I built a 400 for the malibu and pulled the 377.

I tore down the 377 and everything looked good yet, except a little extra wear on the bearings. A guy came to me wanting a 406 for his dirt track car, just to try to see if he liked it. So we decided to throw a cheap engine together. I put the cast flattop pistons out of the 377 on a set of 400 rods and built a short rod 406 with ported camelback heads. He ran that engine for a full season, racing 2 nights a week, spinning 6,000 rpm.

The short rods do put more side load on the pistons, and don't have a good rod to stroke ratio, but they still work.
I just wish they still sold the pistons....

The 400 I built for the Malibu I used stock forged (dished) trw pistons. I decked the block equal distance, and set a stock piston up with a 5.7 rod. I measured how far it came out above the deck and cut the tops of the pistons down for a zero deck, and they ended up flattops. The heads were a 441 casting, with 2.05-1.6 valves, ported, and z-28 springs. I used a 480 lift cam. The car flat out flew with a 2500 stall convertor and 3.50 gears. Idle quality was even good.
Jeff

 

Some cheap extra cubic inches - offset grind the crank and run small journal rods - 5.7 are easy to find, 6.0 a little tougher and more $$$ but cool - I built a cheap 417 (no, not a Donovan!) this way with Vortecs a few years ago - never dyno'ed but had good power for little bucks.

Steve

 

Yea, and the short rod 400 won't make power past 55-5800 rpm anyway

 

Alway use a dual pattern camshaft and stay with "late model" grinds like the
Comp XE series, Lunati Vodoo, Engle EP etc.

 

One word KAAABBBOOOMMMMM!!!!!

 

Nitrous and 400's works well. The stock 400 rods are stronger than the longer rods in other small blocks, and the cast crank is very strong due to increased overlap in the journals. I know more than one person who has sprayed 200+hp into a mild 400 going on a couple of years now.

Blocks tend to be the weak point and any serious hosing should have an aftermarket block.

 

I love this! We're all a bunch of crazy hot rodding mother fuckers.

He asked about an intake and carb. Now we're up to ofset grinding and how much nitrous!

Not being sarcastic and not ragging on anyone, just love the spirit of a hotrodder doing benchwork from the desk of your real estate 9-5!

 

Are they doing the nitrous w/the cast pistons and rings

 

After reading all or your replies, I am wonder if my small block 400 is to much motor for my 54 chevy bel air I am rebuilding. What you think?

 

I think I'll take the advice on the XE256 cam (or equivilant), stock heads and CR , cheap dual plane intake, and splurge on an Edelbrock 1406 w/electric choke and dashpot for A/C.
...boring, HUH?

but I'll be able to keep the stock converter and tired transmission for now, exhaust (it has straight through duals right now with new Brockman M'Tones), and my G-friend can drive it.

This means I can get on with my next project.


...or maybe I'll save this for a killer 406 small block project!

 

Keep the 400!

 

three words...you're fucking wrong !!!
WHEN SET UP AND USED CORRECTLY, nitrous will not blow up a motor.
most nitrous explosions are caused by the engine not getting enough gasoline.

 

six words

It's A Worn Out Bottom End.

The added power will toast that thing in notime. You can only run so much power thru worn stock stuff, doesn't matter if it's coming from N2O or a blower or even a 600 lift cam & pro stock heads. It'll DIEEEEEEeeee

 

i'm with you on that 100%...but i thought he said he was re-building the bottom end.

 

Yep. Low-bucking it........

 

Throw a mild rv cam in it, a new chain, and a dual plane intake. Even a factory cast intake with a q-jet would work good.

And maybe a 250hp NOS fogger
Jeff

 

I got a 400 in my 46 ford sedan,torque,it's a ball to drive,I love it.
Russ

 

Yep- Exactly. If anyone has parts like this for sale- PM me!!
Thx!

 

Whatever you do, don't use an Edelbrock SP2P. Cheaper than cheap, but also the worst manifold ever. I'd still use the single plane, even if it's for your lady. It's gonna get 14 mpg so it might as well howl at WOT. 400s don't obey the manifold "rules" set by 350 and smaller SBCs, they really want the extra plenum volume. Performer rpm at the smallest, tradition be dammed, we're talking about POWER!

 

Shifty, SP2P? Is that a model number or???

 

OK- I get it. That's part of what turns up a ? in my mind whenever I look at speed parts. I know the spec's provided are for ALL for 327/350. I even had a buddy of mine tell me yesterday "why don't you sell that thing-- someone will at least want the parts to make a 383 stroker-- and just buy a junkyard 350??

Anyway- I just assume that the advertised operating range on the cam to be 300-400 RPM lower. In that case, I may have nearly the same HP numbers at a lower RPM (as a 350), and ALOT more torque- all over.

Sounds like exactly what I need to get that 3875 lb moving.

 

I've always enjoyed getting the best bang for the buck, that's just one reason I like Chevies!

When you're messing with an old motor that still runs well and don't smoke, doing more than external bolt ons can get you into trouble real quick. You think "I'll just put in a cam and chain", then you think "while I'm at it I'll put in a high volume oil pump", and you're good, then someone says "might as well put some fresh rings and bearings,,,,,,,,"

 

You truly do "get it". Welcome to the 400 club. We get together every friday and saturday across the nation to beat up the 350 club. Just watch out for the 427 club. They're badasses

 

Ya and it can happen if the motor gets way too much fuel. Last I checked I think we're taken about a stone stock engine which leaves nothing to error.
I'm 44 years old, was born with a wrench in my hand, spent 6 years@ Ross Pistons and the last ten years @ CP Pistons. Ive seen plenty of pistons used to "Alumicoat" the inside of headers. I'm sure we've gotten away with crap in the past that we shouldn't have (like spraying a stock engine) but it didn't last for long. I thought we were trying to give this guy some good advise, not shitty advice!

 

PS. This is for Beetlejuice.

 

If your gonna low buck it for now this is the best advise.

 

Oh ya, forget the fogger or your gonna fog 400 SB all over the place.

 

eh.., ya might wonna check 58 Fridges first post on the first page.

 

I really didn't think he would take the fogger serious. That's why I put this behind the sentence... I couldn't beleive it was even suggested in earlier posts. Worn ring lands can'nt take extra compression and boost from nitrous.

I have never ran nitrous on anything of my own, but I see benifits. With gas prices climbing. You could build a fairly mild engine that gets a little better mileage and spray it when you feel the need. Wrong forum for that discussion though.
Jeff

 

i'm new here' the only difference is that i just pulled the engine & tranny out of my chevelle.. yesterday i stripped the engine down to the block-i'm ready to rock! i like the ideas you all are giving' 1st off i wanna know should i bore or leave it.. it's a two bolt main & i will be sending it out to a machine shop this week.. would love to get a good 450-470tq at the rear wheels..