hey guys. if all goes well i will be picking up a 400ci 2 bolt main long block very soon. I plan on tearing it down to a bare block, getting it magnafluxed, hot tanked, and bored with new cam bearings and freeze plugs. I will build it up slowly as i gain more money, and swap it into my car eventually.

I did do a search, but didn't find anything i really wanted.

I would like you guys to post up your budget 400 combo's (dyno numbers and 1/4 times would be great). All i'm really looking to do is mid-low 12s, maybe a little quicker with some juice?. I would like to know things like if the stock crank & rods are any good, what heads I should go with (are stock heads even worth it?), cam, and intake. It will probably be carbed, so i am pretty new to all this. Thanks in advance !

 

Mine is pretty "budget".

400 2 bolt +.030"
"0 decked" block. 9.8:1 compression
aligned honed saddles.
KB 168 22cc d dish hyper pistons.
Speed pro rings and clevite 77 bearings. (Extra ring end gap for N2O)
GM 350 5.7" rods with ARP bolts
rod bolts clearanced for roller cam lobes.
Stock GM 400 cast crank
computer balanced.
Stock GM oil pump and pan.

GM L-31 vortec heads
Mild porting/ cleanup 2.02x 1.60
Stainless valves. competition valve job
Comp studs, guideplates
spring seats machined for 1.46" springs.
Guide bosses machined for .600+lift
and .530" seals.
Lunati 1.26" 79343 springs.
stock GM retainers comp locks
Crane stamped steel roller tip rockers 1.5:1
1.6:1 intake
.530 teflon seals

Comp Cams XE284H-10 cam
HT-817 hyd lifters
Professional Products Crosswind manifold
Edelbrock 750 cfm carb/ Holley 735cfm vac sec
1-5/8" long tube headers
Modified GM vac adv HEI/ MSD coil (locked timing)
Accel Ignition retard

HP approx 440 to 460 gross BHP
500ft/lbs torque

NOS Cheater Nitrous

Track testing in the spring.

 

Is that the car that was in CC a couple of months ago?

 

Thanks very much FBIRD. i was actually thinking of a combo similar to that, and was wondering if the Vortec heads would work good on a motor that large. They seem to be very cheap, but they get the job done (on the smaller motors, at least). I noticed you went with the 5.7 rods, would it be better to go to a 6.0 rod? any disadvantages to that?

Do those come with 2.02 valves stock? or did you have them machined out.

Would your intake be comparable to a performer or performer RPM?

Irockz- yes it is

 

No point going with 6" rods. don't waste your $$$
This motor never sees over 6200rpm.
Its all about torque with this motor.
Factory vortecs come with 1.94 x 1.50" valves.
I started with new bare castings
Did mild porting and hi perf machining
competition valve job 2.02 x 1.60.
You can buy modified/upgraded vortecs
ready to rock from SDPC.
The ports only need mild porting and cleanup
Even stock unported works.

This motor was designed to last for 20 years.
And run on any brand pump premium fuel.
Its driven on the street and driven back and forth to the track.
Expect mid/low 12's @110 NA

May change the cam to a Comp cs XS-282 mechanical version
if I don't like the hyd. Cam was a freebee.
The intake is a RPM air gap clone.
Holley just introduced a new vortec intake that is a little lower but taller than a performer.

Edelbrock just released a new "RPM air gap" Hi Rise Dual Quad dual plane manifold that looks real sexy. Would fit under your cowl hood. Would be slick looking with twin low profile velocity stacks or a dual quad billet air cleaner.

I've added it to my "Wish List"

 

I've ran low 10s on the juice,consistant 11s N/A,and I love the bore/stroke advantage of the 400.

I'm a fan of the 5.7 rod,good rod/stroke ratio w/o the severe side loading of the cylinder of a 6" rod.

I'm still running a stock crank,but I'm running on pure luck.If you keep the NOS to a reasonable level,you'll have no trouble,as long as you keep rotating mass to a reasonable level.Don't hang a set of heavy *** pistons on H beam rods on a cast crank and expect it to live,it won't.
But a set of nice,light pistons on a good set of I beams,along with a quality balance job can buy you a lot of durability at 500HP or more.

Vortec heads work great on a 400 if your building in a midrange RPM level,which you likely are for street use.You absolutely cannot beat them for the money,as long as you don't mind to spend a little more on them for quality machine work/assembly.

I personally would be looking at a solid flat tappet design cam if I were in your shoes.A little more maintenance,but alot of HP per $,and keep in mind,unlike a 350,or especially a 305/335,400s build alot of compression QUICK,so if you run anything under a 70cc chamber,you'll need dished pistons to run on pump gas.

You'll be pleasantly surprised how quick you can make power when you get cubic inches on your side.
I would definately go carbed,unless you know someone who can set up and tune an aftermarket EFI,it will save you tons of headaches.



Congrats on the spot in CarCraft,That's a huge deal,I hope to join you someday in the pages of the best car mag on earth!

 

Thanks for the info guys. thats the stuff i like to hear. You are really getting my hopes up for the new motor. it may be a couple years before it goes in the car, i will probably wait till the 335 calls it quits...but at least it will be built and ready.

Seems like i will be sticking to my original thoughts, of the Vortec heads (SDPC) and RPM air gap intake. I will grab a set of Eagle rods with ARP bolts, and probably some Speed Pro forged pistons or something similar. I will probably stay with a hyd. cam like the ones you guys mentioned, 230-240ish duration and low-mid 500's lift , since this motor wont see high rpm anyways. I think i should be able to reach low 12s if not high 11s with a properly built combo.

I am picking up the motor saturday, so i will probably start tearing it down after xmas.

One last question. to my knowledge the 2 bolt main blocks are physically stronger. now should i splurge and buy some 4 bolt splayed main caps, or would the stock 2 bolt be just fine with the goals im looking for?

Thanks Irockz & fbird

 

I wouldn't unless you plan on spinning it past 6K, then maybe.

BTW, my combo isn't what I'd call "budget"...but it works! Very sweet looking Camaro you have there TunedPort 335.

What do you plan on doing with the 305 stroker?

I have a totally rebuilt 305 HO myself sitting on a stand that runs great with less than 10K on it, but no one wants it for more than 50 bucks...go figure. And it kept up/ or beat a few 350's!

Anyways, I'll quit rambling....good luck with your 400!

 

a studded two bolt main 400 will hold ~700hp. You'll need about 1/2 that to run low 12's. So yes, the 4-bolt machining would be a waste.

 

I'll either run it till it quits, or when i get bored with it. Then i'll swap in the 400 and maybe freshen up the 335? I really love this motor, and its a blast to drive. i'd like to keep it for as long as possible.


Looks like i'll stick with the 2 bolt main caps. thanks everyone