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Hey guys, after a 5 year hiatus while I went to school, its time to get back at my '46, specifically the powertrain. I have 2 engines I can use, an early 90's TBI 350 from a wrecked pickup and a '72 400 small block from an Impala. Both engines were in good running condition when pulled, and both are under 60k miles. I am looking for a combination that is around 400-450hp, is RELIABLE, and will get the best mileage, although I realize it won't be great with 400+ hp. Two combinations with these motors is a 377 (400 w/350 crank) and obviously the 383. I know of lots of 383's out there, but anyone have experience with a 377? What about heads? Is this a realistic power expectation with just a cam/induction/headers? I am not against going to aftermarket heads if thats what it takes. Any opinions or input is greatly appreciated.

Jeff,
I've been looking into something similar. Take a look at an article I found not to long ago. It's a build up of a 327ci (the engine I have) and they used the Edelbrock Performer RPM package. They got 404 hp on the Motor.

Check it out.

PS: Edelbrock has 'Performer RPM packages' for most engines (chevy, f@rd).

Jim

. . . Sorry about that.

Edelbrock RPM Package

Thanks alot, that would be a sweet little motor. Awhile back I read a HRM article about the "350 Chevy should've built" and it used a 400 block with a 327 crank and con rods from a Phord 300-6. 11:1 compression, 87 octane, and 430 hp. Here's the link:

http://www.purplesagetradingpost.com/sumner/techinfo/350%20chevy%20engine.html

Hmmm, if I could get my hands on a 327 crank, that Edelbrock Performer RPM setup night be a screamer, as it seams the parasitic drag reduction with the short stroke is a factor. Opinions?

Jeff,
Man, what a great trailer!!! Not to mention your '48.

Great job.

Jim

Ho, and thanks for the article. I'll keep it with the others I've come across for the day I go to re-build my SB.

Super Chevy did a build up a couple of years ago. A 391, it used a 350 crank and 400 rods with raised pistons. The pistons had the wrist pin moved higher up on the skirt allowing for the added displacement. I can't remember the exact numbers but it was in the mid 400's and spun up quick... The old tried and true 327 is always a good choice, even GM went back to it in the late model trucks (5.3L). They turn up real good and make decent power with little modification. A fairly mild 350-400 cam sounds pretty nasty in a 327. Just some thoughts.

What are you going to do with this motor?

A bore/stroke ratio with a relatively Long stroke produces more torque than a similar displacement with a shorter stroke.

The 388 approach is likely to pull a load better and be more responsive at lower engine speeds. The 377 is going to spin faster and make more horsepower at higher RPM.

Work truck, or low speed cruiser? Go 388.
Bracket racer, go 388.
Top speed or real drag racing go 377.

Check that 400's block real careful before building a motor based on it. And make sure the machine work to build either combination is done by someone who knows what they are doing. I've heard a fair number of sad stories building either of these combos.

That's my two cents for whatever you want to do with them.

Thanks guys, the pickup might not be a daily driver but pretty darn close, and I really want this thing to storm when you get on it. But like I said, its got to be reliable as I intend on doing some long road trips with it. Maybe I am asking too much. But I suppose it won't take too power to get my little 3000 lb pickup moving. Oh, and if this helps it will have an NV4500 5 speed with a 3:73 rear.

Jeff ,
I personaly would go with a 350 block 4 bolt main , the 400 smallies were notorious for crackin , all they did (GM) was overbore a 350 block an the walls are thin .
Just my 2 pennies

The 400 small block is actualy it's own design. The cylinder walls are siamesed meaning their joined with no water jackets between them. The blocks are then drilled for steam relief holes on the deck. Heads other than 400's must be drilled to match these steam holes before being mounted. The crank is different with larger main journals as well as being externally balanced at the flywheel and harmonic balancer. The rods as well were differnent with a longer stroke. Cooling was a issue with many of these engines but with a large enough radiator and a high flow water pump these can be overcome. A good rebuild on a 400 with 10.1 pistons and good breathing heads is hard to beat in torque .

Sorry for my ignorance Tut ...that is what i was always told , and i did see many fail from heat ...an just never impressed me , had freinds that scavanged the 400's from wrecked trucks etc ...that never lasted long .

I didn't mean to emply that anyone was ignorant, we all add to this site and thats a very GOOD thing. I had a 400 bored .010 (406) years ago in a 76 1 ton, a very strong truck. I didn't have any problems with cooling and used the truck hard daily. 400's are strong on the bottom end and have decent power on the top, they do like GAS though. I still prefer the little 283's and 327's, both good all around engines for your average cruizer.

A mild 350 is going to move it real fast until you need to shift gears.

If you want a quick daily driver I think a motor built for torque is what you really want. Any kind of serious 'racing' that's probably not the right transmission. But if you want a quick response leaving a light or passing, its good mid-range torque that you want.

Longer stroke versus bore (400 crank in 350 block) and modest valves and intake runners to create higher mid range intake velocities are important. But for just playing a little with a daily driver that only weighs 3000 pounds a well tuned stock motor will probably satisfy.

That's not a race car motor but you don't want one of those in a daily driver anyway.

My two cents...

Thanks for the info guys, much appreciated. It kind of sounds like whatever I build is going to work well in this pickup, since it is so light and I'm not planning in doing any serious towing with it. That 400hp 327 has really got my interest though.

Jeff if you are serious about a 327 you can get that kind of power. You will want to start with a 68' or later block as these had larger journals, many with steel cranks and were a lot stronger. Go .010-.030 over and invest in a good set of Hypertunic pistons(10.5 to 1=93 octane / 9.5 to 1 for lower) and cast rings(chrome molly are for serious racing and have a tendency not seat correctly). Spend a little bit and have the entire rotating mass balanced, this is key to and engine living a long life. Use quality bearings and a roller timing chain/ gear set with a high volume oil pump. For the top end you can save a little money and opt for a set of 95'- 97' Chevy Vortek heads, they breathe well and are around 62cc chambers. If you want to open up the intake and exhaust ports just matching the gaskets should be enough. Choose a good mid range roller cam and lifter set, keep in mind that a roller cam makes more power with less lift or duration. Someting around .485 int and .510 exh, use compatable springs and retainers. Roller rocker really help free up power and work well at 1.6 ratio ( of course chrome molly pushrods). For the intake a Edelbrock Performer RPM with a Holley Street Avenger 670-770, these will make power right out of the box. A DUI electronic distributor is a good choice and allows you open the plug gap up to .060. Use an standard length header with 1 7/8 primaries and good mufflers. You will be able to blister the tires (if you can hook up) and still have a decent street truck. I have close to the same set up in my 59', only with a muncie, your 5 spd should only help. Just swappin' some ideas. :p

Thanks TUTS, what about basing the 327 on the TBI block I have? Is there anything that needs to be considered with the later blocks?

Jeff, same same. The better you prep the block the better results you'll have. The later model 327's (5.3L) will have a few differences.They have one piece rear main seals, they don't have the fuel pump boss and the lifter galley is machined for roller lifters. The cam sets higher in the block and uses a different type timing chain with an idler gear. Heads are is still interchangable, but you must use a roller cam. The cam is already a roller and the heads breathe real good. You may need to do something different with the distributor if it's crank triggered. They also use a reverse rotation waterpump, for use with serpentine drives. The intake manifolds have different bolt pattern. If your planning on keeping the TPI wiring harnesses are available from the aftermarket. The key is it's still a Chevy and a lot of things work together. Ever wonder why phords at car shows use chevy engines.