[greaser666]

is it possible to put vortec heads on a 400 small bock if it is. would it be worth the money.










spell check is fixed

[Siggy_Freud]

I dont see why not unless there was an issue with steamholes not being able to be drilled. I think Vortecs might make for a good low end combo but I there are many better options out there as far as heads go. They are decent for the low budget build. But if your not going to take full advantage of that 400 then send it my way .

[greaser666]

tell me what i need to do totally new to this. American hotrod.stuff if it was a Honda it would be a different story.i have been racing Honda's for about 6 years.forgive me i was lost. any way give some ideas its a Dayle driver. so its got to be street able

[streetfytr68]

Hey there. Vortec heads may be a little small for a 400 if you plan to really rev the engine--might run out of steam at about 4500rpm. But if you will only use your car for cruising, you can't beat the price and performance of Vortec heads.

400 blocks have siamesed bores. So steamholes must be drilled in non-400 heads. As the name implies, steamholes vent coolant vapor from the block. Here's a good picture of the drilling process. Use a 400 head gasket as a guide and a 1/8" bit. Just be sure to visually inspect the water passages before drilling. Note that since I would not personally use Vortecs on a 400 I have never drilled steamholes in Vortec heads. Maybe someone else here has done so and can check in. Should be OK though.

[MI2600]

I've got Vortecs on my 406. I had the machine shop drill the steam holes for $30. It was worth the peace of mind.

I'm running a TRW forged, dished piston to get the compression down to 10:1 static. I used the Comp XE268 cam. The 400 is not a high winding engine, so I'm not concerned about anything above 5,000 rpm.

Before I changed out the original 2.41 rear gears, this combination would still break the tires loose.

[1quiknova]

I built a 400 with vortec heads for my buddy and with jsut over a .500 lift cam with around 250 duration at .050 that motor made a lot of torque, if i had to guess it makes around 550 ft/lbs at low rpm, it is a sweet street motor. All you have to do is match of the gaskets o nthe heads and drill for the steam holes.

[greaser666]

cool thanks for the info guys. found a set at a second hand speed shop.totally reworked for 550.00. is that good deal ???? sounds good

[Siggy_Freud]

Find out if they have been modified to run larger valve springs. You'll want that so you can run a decent cam in the 400.

[GoneNova/406]

i don't know why but i have never been a big fan of the vortecs.they flow very well after working on them first and spending more money but you usually have to do that with other heads to.if you find that you like vortecs check out the june issue of chevy high performance magazine.they have an article in it about the all new redesigned vortec head and come right out and say it is with out a doubt the baddest best head ever made by chevy.flows way better than the old ones.

[tornado-tech]

Vortecs heads have a 64cc chamber. You will need a dished pistons to run pump gas with these but they provide excellent torque and midrange. Also they are limited to .500 lift. If you already the short block built with either 2-valve or 4-valve flat tops, I am having a friend sell my old S/R Torquers on Ebay: http://cgi.ebay.com/ebaymotors/ws/eB...sPageName=WDVW. These heads with 2-valve flat tops gave me appr 10:1 compression. I went with a 200cc intake runner to allow more airflow at higher rpm's since I am after maximum hp around 5800rpm.

[NAIRB]

The vortec head is probably the most logical choice for a street/strip 400. They sport 170 CC intake runners, which might seem to be small compared to some of the big numbers touted by others. They flow very well for their size. They definitely will perform over 4500 RPM. Most 400s are 5500-6000 RPM engines anyway. Still the best performance head for the money. You can buy a good set of cores for 250 bucks. Many times, the guides and seats are in very good condition. Just check for cracks and try to avoid getting your heads from a core supplier. A junkyard that visually checks them is probably the best place to look for them.

If you've never drilled your own steam holes, I suggest that you have it done. The holes that get drilled next to the bolt boss have to be drilled at an angle to avoid drilling into the bolt boss itself instead of the water jacket area. You have to drill a small pilot hole vertically, then drill at a minimum 45 degree angle. It's tricky to do by hand, I use a seat and guide machine to do mine.

You will also need to have the springs replaced, and the guide bosses machined down in height and also in diameter so you can use a common Z-28 type spring.

If your heads are crack free, and have minimal guide and seat wear, and are flat, you can clean them, lap the seats in , have your holes drilled and guides machined, install some $20.00 Z-28 springs, seals and you have a very inexpensive set of high flowing heads.

If you don't have a valve spring compressor, and are unfamiliar with basic cylinder head assembly, you will have to pay a shop to do it which will drive the cost up. Find some good machine shops and do some price shopping on some of these basic services.

[GoneNova/406]

the new vortecs are 206/77 cc runners,65 cc combustion chamber and the deck is .045" thicker.they are machined for screw in studs and will accept .530" lift cam with out modifications.the valves are 2.00/1.55.complete 539.95 and bare 293.25 per scoggin-dickey.enjoy boys!

[Mighty Mouse S-10]

[QUOTE=tornado-tech]Vortecs heads have a 64cc chamber. You will need a dished pistons to run pump gas with these but they provide excellent torque and midrange.

I run a set of bowtie heads 64 cc's with flat top pistons on pump gas with no detonation problems at all.

Dave