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400 sbc

yep my 400 was 40 ove with 5.7 rods and flat tops and a set of worked over well camel humps....i still ran a cast crank but everything was balanced...i paid like 80 bucks i think to get the steam holes drilled...just beware of the pistion to valve space....my motor started as a simple motor and ended up as a 500 hp monster on racing fuel...not what i originally started out lookng for...
 
you have to get pistons that are made for using the 5.700" rods in the 400 then right?
btw, i want to go with 10.5-10.8 ish cr
 
i dunno really i got a deal on all my stuff...i bought
1.7 pistions and 7 rods...the wristpin broke on one...finding the right rod,pistion,wristpin to get ballanced was a pita..
2.a set of headers
3.the camel humps w/202/160 with porting done
4.a full set of roller rockers
5.a set of tall valve covers
6.a victor jr intake

all for 250 bucks...i made out like a bandit...
 
holy hell man, id say so. got a q about the stock 400 heads. would i be better off to have them worked (port and polish, gasket match, maybe 2.02 valves, and a 3 angle job, ect) than getting aftermarket aluminum heads?
 
here is my advice go out and buy the rpogram desktop dyno...its like 30 bucks...spend a full day or a whole week plugging all your specs in the program and go through a jegs or sumit and match stuff up...thats the best way to build a motor in my opinion...thats just my .02...
 
87 Blue Beast said:
you have to get pistons that are made for using the 5.700" rods in the 400 then right?
btw, i want to go with 10.5-10.8 ish cr
Click to expand...

Yes if you use a 350 rod then special pistons are required. There are so many people making parts to build a 383 that the prices have come down alot over the years.

To run 10.5-10.8 CR you are going to need race gas unless you run aluminum heads and even then it will probably give you headaches. You can build an engine with LOTS of power running 9:1 CR. It's all in matching the components and paying very close attention to what you expect the engine to do.
 
what does it matter if i use aluminum or cast heads as far as cr? my uncle is running 10.6ish cr in a 355 with cast 2.02 heads with no problems at all and its between 425-450hp. is it tuning issues? knocking? temperature? i want some opinions on speed pro hyper pistons, the ones with the coated skirts. i hear they are decent for the price. ive used them in a v6 (3.1) that i build and had no problems but this will be pushing acouple more horses... so heres what im thinkin so far... eagle forged i beam rods, speed pro pistons, nodular steel crank, and not sure on either cast or aluminum heads, in a 2 bolt 400 block bored .030 over (406), not sure on carb'd or tbi...
 
b454rat said:
I know I've mentioned this before on this board bout the TBI 406 that I built for my old truck.

400 4 bolt block, 30 over. Basic bore/hone, nothing special.
Stock 400 crank, new flexplate and balancer, stock replacement.
5.7" rods, stock out of something. ARP studs.
KB hyperuetectic pistons, IIRC 22cc dish
Whole rotating assembly balanced.
Comp Cams Xtreme Energy 268 cam/lifters.

STOCK heads, rebuilt with the steam holes.
STOCK intake
STOCK TBI (did have new injectors)
STOCK ECM

Nothing done to any of it. The motor ran friggin' awesome. Would idle all day long, (nice choppy one too) had torque to smolder the tires off at will.
Still get about 20 mpg on the highway. I never had it dyno'd, but a WAG at 350 horse, and 400 ft/lb torque. The truck never had any problems overheating, check engine light never came on. I wish I kept the truck.
Click to expand...


Mmm, no, more around 315-320HP or so, at best.

I have the same cam as you in my 406, same stock heads, Edelbrock performer intake, 9.2 CR, headers, and an edel Qjet..... I laid down just a hair under 200HP and 300ft lbs to the ground on the inertia dyno.
 
87 Blue Beast said:
what does it matter if i use aluminum or cast heads as far as cr? my uncle is running 10.6ish cr in a 355 with cast 2.02 heads with no problems at all and its between 425-450hp. is it tuning issues? knocking? temperature?
Click to expand...
1. Aluminum transfers heat better. The head actually will run slightly cooler in the upper chamber and help combat detonation compared to iron heads.

2. 350's and 400's are VERY different. 400's actuall cylinder temps are considerably higher than any other small block, or big block that I am aware of. This is due to the siamese cylinders, the coolant doesn't completely soround the cylinder thus creating noticeably higher cylinder temps. Combined with a tight compression, iron heads, and you'll have detonation issues.

Stay around 9.1:1, or 9.5:1 with aluminum heads AT MOST. My iron headed 406 runs a 9.2 CR and I HAVE to run 91 octane or it'll ping. If I pull a trailer, I've got to add octane booster to the gas or it'll still ping. Would I have this problem with a 350 setup the same? Nope....

A 4bolt 400 block may be able to handle 700HP down the 1/4 mile ONE time, where a 2 bolt might blow, but a 2 bolt won't crack up like a 4 bolt will under normal applications. Plus..... you have no idea how lucky you are having an original bore 2 bolt 400 just given to you..... people like me would pay you good money for that block....

GO WITH AFTERMARKET HEADS! Stock 400 heads suck, they are basically the same size heads that you can find on a 350. Pump up a 400 and the stock heads get too small very fast. Average consensus was that I would have gained upwards of 60-70HP on the dyno if I had a set of AFR aluminums over my stock POS rebuilt 400 heads. For what heads cost, a $750-1,500 investment to grab another 50+HP, it's a no brainer.... Plus, with good heads it opens the door to build a real motor with a blower or turbo.
 
ok, so aftermarket aluminum 2.02 or bigger heads are a must. got it:D . but i still want to run atleast 10.1 cr... if i run 10.1 with 93 octane and aluminum heads, would i be ok?
 
also, what about cam selection? i want good, clean, crisp throttle responce, but i dont want the power to die in the top end. probably a power banc of something like 1500-6000 give or take a couple hundred. im not selecting the cam by the sound, but the rougher the idle, the better :D . i guess what im trying to say is that i dont want, or it doesnt have to have a smooth idle:wink1:
 
4X4HIGH said:
The biggest reason people run the 2 bolt 400's are they are WAY easier to find than a 4 bolt 400.
Click to expand...

I gotta argue that one. World and Dart have them all day long for just over $2k plus shipping:haha:

Stock 400 rods are useless. Eagles are ok but with all the aftermarket cheap rods get them checked for size on both ends. Odds are at least a couple will be tight somewhere and Eagle is not responsible for a failure if you fail to check them before assembly.

On the heads, iron vs aluminum, its a toss up. A good set of aftermarket iron heads will do a great job on a torque motor. Keep the intake runner size down to 195~205cc to keep airspeed up at low rpm for better throttle response. This is really more a budget question right now. But I wouldn't pay much for a set of original camelback heads. There is better technology at better costs out there.

Intake manifold, run a dual plane like an edelbrock rpm air gap. A single plane like a victor will get you more hp over 5500 rpm. But building a 406 how much time are you spending up there in a trail rig? Trail rigs need throttle response from low rpms, and that ain't a victors strong point.

Camshafts, if you have the bucks get a roller. They will get you more power than a flat tappet cam with a nice smooth idle. Remember the TBI?:wink1:

Thats a start
George
PS on the 2bolt 4 bolt thing...Scotts right on clamping load. The others have a point about cracks in the main webs too. So to me its a coin toss and depends on whats available for the money
 
yeah, i dont think im goina go roller. id like to but i have to try to stay on the less expensive side. a nice choppy flat hyd cam will be just fine. like i said, tryin to stay on the cheaper side, but not goin to skimpy. btw, im thinkin less and less about tbi, cause of the tuning and limited cam selections, and the money part
 
Have you considered just going with a Big Block? I'm a big block fan. They are beefier in almost every way and with the longer stroke will make loads of torque at low RPM's. Do what you want, that's just my opinion.
 
yeah i have.. but i dont wanna. i love small blocks. they are cheaper, more aftermerket, more parts, more variety, and almost everything is interchangeable. plus, I GOT A 400 BLOCK FOR FREE!!! :D
 
87 Blue Beast said:
also, what about cam selection? i want good, clean, crisp throttle responce, but i dont want the power to die in the top end. probably a power banc of something like 1500-6000 give or take a couple hundred. im not selecting the cam by the sound, but the rougher the idle, the better :D . i guess what im trying to say is that i dont want, or it doesnt have to have a smooth idle:wink1:
Click to expand...
how many times do you have to be told...GO BUY THE DESKTOP DYNO PROGRAM!!we cant sit here and tell you how to build your motor but you might not make is much power as you can be...a bigger cam isint always better...i agree with the other guys too...i was running a 408 w/11.5 to 1 on straight 104...
 
i dont know,why dont you go ask my buddy who uses it for his race car...mabye he can telll you...im sure the cam caculator,compression calc,and graphs are all wrong...come on man...
 
dude.. chill out, seriously. i wasnt doubting it, i was asking you a simple question as to how accurate it is... like with in how many hp/tq does the engine make in comparison to the desktop dyno. just for the record, i already ordered one, so im not doubting it :surepal:
 
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