400cid?

[Guest Anonymous]

What cars/trucks did the 400cid engine come out of? In the previous post "383 or 373" Someone about putting a 327 crank in a 400 block with like vortec heads. Would this work? What kind of numbers would this produce?

 

J

[Peternell]

The 400 was produced from 1970-1980. The 70-72 blocks were 4-bolts and the 73-80 blocks were 2-bolts. The 79-80 block can be a little deceptive cause they don't have 3 freeze plugs like the previous blocks (look for the 8" balancer w/some material missing for external balancing purposes.

 

The came in trucks, vans, large sedans and station wagons. The truck engines have probably seen the most work and the sedans the least work. Try looking into 1971-1976 4-door Impala's and station wagons.

 

Yes the 327 crank (3.25" stroke can go in the 400 block just as the 350 crank (3.48" stroke) can. You must use special bearings or bearing spaces to make up for the 400 having larger mains. (I assume you talking about a large journal 327 crank?)

 

Putting Vortec heads on a 400 is almost the same as putting them on an early 350, just remember to drill the 6 steam holes per head. Alot of people swapped high compression heads of 400's to boost power and then complained that they overheated. Not the 400's fault, but the owners cause they forgot to drill the steam holes.

 

327 crank/.030 over 400 block is a 352 (I think?) A racer with a 70 chevelle runs this combo and does quite well, however redid the engine for this year with the 350 crank for nearly the same rev potential yet 25 more cubes.

 

The 352 can easily fit a 6" rod, just make sure you get pistons with the right pin height.

 

Between the two I'd go the 377 route!

[DavyZ]

Ditto on the 377--a lightened Scat 350 crank set up for the 400 block is the bomb.

[Guest Anonymous]

The 377 route would be a 350 crank in a .030 400 block? What would be good heads to use for that set up? What kinds of numbers would it produce?

[Ray]

The main reason some people use the 327/307(they are the same) crank is to get a longer rod and the cylinder filling effect with the larger piston. This combo also fits alot of class racers that are limited to 355cid. With a light piston and 6+" rod this is a real high end screamer. As for doing one with the vortec heads I would think it would run about like a regular 350 with the vortec heads. The reason for this is the vortec heads are only good to .500 lift and this combo would need a really large cam and some big heads to take advantage of the long rod. Now the rod would help a milder motor with the vortec heads but why spend the money on custom pistons and rods when the gain isn't that great.. IMHO Now if you are going to build a 8k screamer or are trying to make the motor fit into racing class go for it....

 

Most 307/327 cranks are forged, you can use either the ford 300/6 rods(6.209") and have the top end bushed to a chevy pin and narrowed, or buy custom rods... both will require and aftermarket piston. I have heard that some of the hyper pistons for a 6" rod 406 will work but don't recall what rod they were using.

 

------------------

Remember it is only a piece of metal.

 

[This message has been edited by Ray (edited April 03, 2001).]

[Kevin Shasteen]

I'm considering the 377 as well for the toque probabilities but also its revability....as if I'll ever actually get to begin my swap(?)!

 

The best of Hotrod Magazine; Volume 9 "How to Build Big Chevy Small Blocks" had a 20page 4part article(s) on the "Budget 377" build. They attempted to keep cost under the $5000 range.

 

Their dyno ran just missed the 600hp mark. They used Edelbrock Victor Jr.cyl.heads which gave 212cc intake runners & 70cc combustion chambers; after porting (Personal note: They're only pushing 212cc's on their intake side. I've mentioned in other HybridZ Threads that "too large" flowying cyl.heads hurt airflow. This article has an engine rev'g to 7k rpm's & chose a smaller cyl.head. Granted they chose a huge carb/intake but it matches their purpose & camshaft choice).

 

Their choice of cam was a custom Roller Rocker from Isky: 264/272 @ .050 w/108 lobe seperation angle. Chose 1.65:1 rockers on the Intake & 1.5:1 Rockers on the Exhaust W/Titanium locks for the valve springs.

 

They intended this engine for GT Racing & wanted hp on the high end. Intake choice was an Edelbrock Victor Jr.

 

They ran three test on the dyno & the best Dyno run was using a 2"TD spacer & a Barry Grant 850 Holley.....589HP @ 6500rpm's & 516ft.lbs @ 5400rpm's. They ran the engine on the dyno all the way up to 7000rpm's where it produced 576hp/432ft.lbs.

 

BTW: this book also outlines other Big Inch SBC builds like the 383, 406, 408, 427 & 454 SBC builds.

 

Found the magazine at Barnes & Nobles...again it was Volume 9 of: "The Best of Hotrod Magazine/Technical Library" Published by "CARTECH" & I found it in the automotive section of Barnes & Nobles. If they dont have it they can order it! Great Info!

 

Kevin,

(Yea,Still an Inliner)

 

 

[This message has been edited by Kevin Shasteen (edited April 03, 2001).]

[John Scott]

Kevin, this build sounds similar (cam specs) to my friends 377. He was well over the $5K

 

using high dollar 6" rods and JE pistons. Angle milled Brodix. The thing sounds like a screaming banshee, shaking the house, literally, 1/2 block away. With cam specs like that, I don't know if the idle ever smooths out!! He claims the 2 bolt is stronger than the 4 bolt conversion(?) Can run pump gas with the 11:1s, but prefers the good stuff for a little more timing. Certain block castings are preferred. Anyone know the casting #s? Ungodly fast and trouble free for 5 straight seasons.

 

I want one!

 

JS

 

[This message has been edited by John Scott (edited April 03, 2001).]

[Kevin Shasteen]

Yea, I always question alleged "Cost Builds" in articles when I read them. I'm sure some of the #'s are skewed as the "in-house" labor for machining at the high dollar machine shops are now lowered or even eliminated sometimes just to reach their objectives simply for 'sales' of magazines.

 

Still, the 377 is & has always been one bad mamma-jamma of an engine. I'ld definately want one; if I could afford one!

 

Wasnt there also a thread on HybridZ a few months ago that someone posted-which listed a URL that discussed a 377 build using special JE pistons and taller rods and allowed the piston to stay higher in the bore which netted the same HP/Torque w/out detonation even while using lower grade pump fuel? I dont know who posted it or what the title was but that sounded like a killer combo: a 377 w/all the power & capabilities of using lower pump fuel(!). Where/What was that thread titled?

 

Kevin,

(Yea,Still an inliner)

[Guest RON JONES]

Stud the two bolt mains and your all set.My old 468cid 715hp BBC was a two bolt block w/studs.Never had a problem.I have also heard the samething(thats why I used one)about the two bolt block being stronger.

[pparaska]

Kevin, I talked about the longer dwell of the piston per the 352 (327 crank/400 block), but it's just a function of the rod/stroke ratio. That particular buildup had a 6.2" Ford 300/6 rod that Ray mentioned, and a very high rod/stroke ratio for a SBC. What I like about that setup is that it gives more octane tollerance, so you can run more static compression and/or less overlap.

[Guest Anonymous]

Pete I may have mentioned that 400 ci 327/307 crank 350ci combo as well (the 350 chevy should have built)Hot Rod June 97

412hp 435ft/lbs and 400ft/lbs from 2500-5000 rpm 11-1 comp 87 octane gas and $3000!!

Getting more out of this combo could be had since it only has a 215 @ .05 dur.

 

I think the key is the longer rod for the dwell time yes like previous people have mentioned this means custom pistons but I think it is worth it.I would love to see a back to back long rod 350(like this one ) against the 377 would the 27 ci be enough? How many 400hp 87octane 350 have you seen?

[DavyZ]

400hp on 87 octane is sooo cool! That engine you could take anywhere! Do you remember the heads they used and the specs for the camshaft? I'll try to dig up this article if I can find it. Doesn't HotRod have online archives now?

 

David

[pparaska]

I found it again. I think someone here pointed the URL out to me. Anyway the article is "The 350 Engine Chevrolet Should Have Built." It was in the June 97 HotRod Magazine. Here's the URL:

 

http://www.airflowresearch.com/Articles/A3-P1.htm

 

They used AFR 190 heads for the 305 with 56cc chambers and 1.990" intake valves.

[DavyZ]

Ahhh yes, that's the article. Thanks, Pete, for posting that!

 

David

[Kevin Shasteen]

Yep; that's the URL Pete; you get an A+ for the day!

 

Kevin,

(Yes,Still an Inliner)

[Guest Anonymous]

Guys,

 

Correct me if I am wrong but I don't believe the 352 SBC being discussed would require custom pistons. All that would be required would be standard off the shelf high performance 400 pistons for a 5.7" rod length. Eagle makes a H beam 6.2" rod that seems to be fairly reasonable in cost. Use the 400 pistons (for 5.7" rods), 6.2" Eagle rods and a 327/307 crank and you're set!! Trouble is finding an acceptable 400 block...

 

Chris

[Guest Will]

My father and I REALLY want to build one of those engines with a set of Vortec cylinder heads and a modified LT4 intake manifold. We just have to figure out what kind of car to put it in. As I said in my current t56 thread, I'm looking at a '73 Triumph Stag.

 

For the Z we're going to build an LT1 based 302 (327 bore/283 stroke) with similar rod/stroke ratio to the above engine.

 

Large Rod/Stroke ratio RULES!!! The Z currently has an L99 from '94 Caprice. That engine has a R/S ratio of around 2.0:1 and never skips a beat on 87 octane w/ 10:1 compression.