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Author Topic:   355, 383, 377, 406CI ENGINES
SLIDE JOB-N.Y. STYLE
Dirt Roller

Total posts: 12
posted September 19, 2000 03:21 AM
I AM NEW TO RACING AND WAS CURIOUS AS TO WHAT BLOCK YOU START WITH TO GET THESE ENGINES. I'M PRETTY SURE THE 355 IS A 350 BORED TO A 355. AND THAT THE 383 IS A 350 WITH A 400 CRANK. I THINK MAYBE THE 377 MIGHT BE A 400 WITH A 350 CRANK NOT REAL SURE ON THAT ONE THOUGH. AND THE 406 I IS A 400 BORED. I DON'T WANT TO SOUND LIKE AN IDIOT BUT CURIOUSITY IS GETTING THE BEST OF ME. AND ALSO MAYBE A LITTLE INPUT ON WHICH MOTOR YOU THINK IS THE BEST AND WHY.

THANKS
SLIDE

chomme
Dirt Full Roller

Total posts: 52
posted September 19, 2000 09:41 AM UIN: 1986763
Hi There -- You are correct, a 355 is a .030 bore 350. A 383 is a .030 350 block with a 400 crankshaft (commonly called this...it can be built with any 3.75" stroke crankshaft in a 350 block), and a 377 is a 400 block bored .030 with a 350 crankshaft (commonly called this...it can be built with any 3.48" stroke crankshaft in a 400 block). The 406 is a 400 block bored .030 with a 400 crankshaft installed.

As to my opinion on them, I have run 355's, 383's, and 406's. I have several friends that run 377's. On the 355's, depending on the track size, car weight, etc, they can be very good and are probably the cheapest engines to build. On the 383's, they are also very powerful, however, I will say one of the big things on a 383 or 406 is do not use the 400 connecting rods with that combination. They are only 5.565" long and would make the motor have a pretty bad rod angle. In all my small blocks, I use the 350 5.7" connecting rods. As to the 377's and 406's. The 377 is a very good motor and can rev very well because it is the 350 stroke. The crankshaft will require main bearing spacers be used to bring the main's down from the 400 main journal size down to the 350 size, then standard 350 bearings are used. On the 406, you use a regular 400 crankshaft and I have used regular 5.7" connecting rods in those motors. The 400 can be a little tricky to cool (water does not flow between the two center cylinders in a 400 block), however, as long as a decent water pump, set of reduction pulleys (30%), and a good fan shroud are used, cooling will be no problem.

It seems to be an ongoing discussion that the 377's are the way to go on short tracks because they can rev quicker. I am not sure what to say to that. I am currently running a 383 in my dirt car, and there are 377's and 406's in my class, and nothing can touch my 383. And it really isn't that built of a motor, either. I'm running a Scat cast steel crankshaft, GM 5.7 PM rods (the new corvette rods), TRW hypereutectic 12.5:1 pistons, a crane solid cam, 292 angle plug cylinder heads (that are ported), a brzezinski intake (we have to run a production 2 bbl iron intake), a modified Holley two barrel, and a K&N Flow Control air cleaner. Even with the 2 barrel and the intake, the motor dyno's at over 425HP, which isn't too bad for a restricted motor like this. And I turn it up to 6500RPM or so with no worries (the 2 barrel is the big limiter to RPM potential).

If you have any questions, feel free to message me.

Thanks,

Chad

SLIDE JOB-N.Y. STYLE
Dirt Roller

Total posts: 12
posted September 19, 2000 10:31 PM
CHOMME,
THANKS FOR THE INPUT. I THINK THAT 383 MIGHT BE THE WAY TO GO.
WHAT CLASS DO YOU RUN?
ALSO WHAT IS YOUR OPINION ON THE 358.

THANKS

SLIDE

chomme
Dirt Full Roller

Total posts: 52
posted September 21, 2000 03:51 PM UIN: 1986763
I run a Pro Stock here in Placerville, CA. I will also be running the upcoming Fallon/Reno-Fernley open show in Nevada. So I am switching to a brodix intake and a carb that was just dyno'd specific for my motor. We will see how it runs. I am very happy with the 383's...if you are interested, I have a spare cast steel 383 crank that is brand new that I would sell, just PM me.

Let me know if you have any other questions...over the next year, I will be selling off most my stuff...going to be running an asphalt late model and also an asphalt modified.

Thanks,

Chad

Mudbuster
Dirt Full Roller

Total posts: 72
posted September 21, 2000 10:57 PM
We have been satisfied with 383's for the past 6yr's but we recently put a 377 together and have been flying ever since.We run in Texas where as everyone knows it has been extremly dry but we have been able to get hooked up and have decided we like this 377 so much we will build more of them.406's were to much for our track conditions.

VIPER000
Dirt Maniac

Total posts: 151
posted September 22, 2000 10:44 AM
A PROBLEM WITH THE 383 IS IF YOU ARE NOT AN EXPERIENCED BUILDER SOME CLEARENCES CAN BE A PROBLEM. ALSO LOCALLY MOST OF THE TOP CARS RUN 406'S THEY HAVE MORE TORQUE THAN THE 355'S AND 377'S. ALSO ARE CHEAPER THAN 377'S AND 383'S. 355'S WOULD BE THE CHEAPEST AND MOST COMMON FOR USED PARTS. I ONLY KNOW OF ONE PERSON AT OUR LOCAL TRACK THAT RUNS 377'S AND HE USES IT BECAUSE HE GOT IT IN A TRADE. BUY THE WAY I DON'T THINK HE HAS EVER WON. THE LOCAL TRACK MENTIONED ABOVE IS A LONG 1/4-SHORT 3/8 MILE BANKED TRACK RUNNING 3400 LB STREET STOCKS. ALSO WE USE HEADERS ALUMINUM INTAKES AND 4 BRL CARBS SO WE HAVE THE FLOW FOR THE LARGER ENGINES

[This message has been edited by VIPER000 (edited September 22, 2000).]

chomme
Dirt Full Roller

Total posts: 52
posted September 26, 2000 12:27 PM UIN: 1986763
That brings up a good point, on a 383 or 406, be sure to check the clearance between the rods and the block (there will need to be clearancing made for this) as well as the rods clearing the cam. I am running a crane solid cam and my rods required no clearancing. They are the new GM PM 5.7" rods. Also, the block did require clearancing by the bottom of the bores to clear the rods. I paid my machine shop to clearance the block, file fit the rings, and fully assemble/blueprint the short block, it ran me $200 which I think was very worthwhile. To give you an idea, my machine shop did the block (bored, line honed, decked, cam bearings, freeze plugs), clearanced the block, file fit the rings, fully assembled the short block, and balanced the assembly...and the total machine shop bill was about $620.

--Chad

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