Best 350 sbc casting?

[bubbas]

Which is the best out of these two castings?


3970010 or 3970014 I have both but they are two bolt mains.

Also I was told that the 400 engine with a 3.25 crank would be stronger than the 350 3.48 stroke our Cubic Inch limit is 362 in the Street Stock class on a 1/4 mile dirt oval.

I think there is a rule against running a 400 block but could I change the casting numbers because the tech man is not that smart?

Thanks Bubba.

[CNC BLOCKS]

Which is the best out of these two castings?


3970010 or 3970014 I have both but they are two bolt mains.

Also I was told that the 400 engine with a 3.25 crank would be stronger than the 350 3.48 stroke our Cubic Inch limit is 362 in the Street Stock class on a 1/4 mile dirt oval.

I think there is a rule against running a 400 block but could I change the casting numbers because the tech man is not that smart?

Thanks Bubba.

Bubba

If the 010 block has 010/020 on the casting behind the timing cover or in the bellhousing area that may be a better peice if its passes the sonic test as we have done machine work on both blocks and like I have said go by the sonic test to make a better decision. To run that crank in a 400 block if the crank has 350 journals it maybe costly for bearings and spacers.

On the 400 block you might want to change the freeze plug hole on each side of the block as that is a dead give away for a 400 block as they have 3 freeze plugs per side or at least the bosses are there.

[bubbas]

Thanks Carl.

You say the 400 engine has an extra freeze plug and that is a dead giveaway.I dont guess there is no way of hiding the freeze plug?...lol.

We have a track here in Louisiana that is a 1/4 mile with these classes Factory Stock-Hot Stocks-Southern Stocks-Modifieds-Limited Modifieds.

There is a professional engine builder here building some of the factory stock engines that run like the Southern Stocks i.e.Street Stocks.I know they cannot be legal but nevertheless are getting by tech.Some of these guys cannot drive and are just out powering the other cars down the straights.

The rules say no stroking or destroking and can run only open chamber heads with stock type manifolds but no center dump manifolds and max of 447 lift hyd cams and quad carbs and stock intakes.Most cars are GM Metric frame 108" wheelbase cars but run like bats out of hell.These cars are also running turbo 350 automatics in low gear with around I suspect 688 final drives.

There are only 4 of these cars I question.

Thanks for your advice.
Bubba.

[CNC BLOCKS]

We have built some engines for guys with money as the rules say stock stroke cranks and stock rod lenth as we have used some Honda rod 283 main from King's Crankshaft company that weighed 31 pounds and used the Tour lite rods from Manley performance as these 2 engines come of the corners like Rockets and there legal it just depends on how much money you have to spend.

[Adger Smith]

Bubba,
The 400 block also has a small raised area on the outside of each cylinder. All small bore blocks have smooth, non contoured, water jackets on the outside of the block. You can spot it a mile away. If you are the same Bubba I think you are, stop by the shop & I'll show you.

[bubbas]

No Adger dont believe we have ever met.I realize the the 400 block has the extra freeze plug ect.I am building a factory stock for a friend of mine it is a 82 monte carlo and we want to build it to fly.We are limited to open chamber heads 1.94 Intake 1.50 Exhaust valves pressed studs and 447 max lift hyd cam.Stock Intakes and quadrujet carbs and automatics with funtional torque convertors.

We are allowed to run 350 C.I. Engines but the rules say no stroking or destroking but some of these cars run like stroker motors and pass tech.

Would the 327 C.I. Be a good engine to build to run with these 350`s?

Someone has said since the rules say no destroking change the casting numbers on a 350 block to 327 casting numbers and put a 3.25 forged crank in it with good rods and forged pistons ect.

Would the 327 be worth my trouble?

Thanks.
Bubba.

[Adger Smith]

Those sound like SIMS rules. If you are limited on tire size or traction limited then I would consider an engine with more RPM potential that has less torque. (don't blow the tires off with torque) you could click it up a gear ratio or two to get good multiplication to get off the corners & RPM the rest of the track. The head limitations might make the smaller cu in more efficent. There is a track in Vivian La. that has a class similar to what you are talking about that only allows open rear ends. (one wheel pull) I thought you might be the Bubba that is a customer of mine that runs this class & is in second place in points.
If the lift rule is measured at the valve remember that stock rockers have a bad habit of being shorter than the 1.5 ratio & figure in the deflection of the valve gear with good spring pressures. Build the engine like an NHRA stocker. Take advantage of all the small things & use good machine work to make power.
It has been my experience that most people that run these limited classes seem to over gear & run the engine completely out of the HP & Torque curves. I have had customers go from the back of the pack to the front when we dyno the engine & gear according to what power curve the engine has. Run the gear your engine/car likes, not what Leroy or Jr. told you that they, or so & so run!!!

[bubbas]

Yes Adger I have heard of the track in Vivian called Ark-La-Tex speedway.I have never personally attended it myself but plan to in October to see who wins the run for $5000.00 to win in the factory stock class.

When I go to the races its usually Champion Park speedway in the Minden La area a 1/4 mile dirt oval.

I built a car and sold it a grand prix my cousin built the engine to hot rod on the street its a 400 pontiac engine and I bought the car and caged it out for a factory stock and sold it to a friend of mine.I dont know why the 400 pontiac at idle when it get around 210 degrees looses oil pressure down to 0 unless the rpms are kept up and its fine but if he lets it idle low it has no oil pressure.He run the car once and said he wanted to get the oil pressure fixed before racing it again.

I ran the 400 pontiac on the street hard and it never lost the oil pressure at idle and dont really know what the difference would be?

Any advice why you think the 400 pontiac looses oil pressure at idle when hot?

He runs Castrol 20w 50 but its not synthetic.

I may have to start using you for my machine work because have had some bad luck with Kittlers Automtive Machine Shop in bossier city and also Competition Automotive on hollywood Avenue in shreveport.Its hard to find good service these days....lol

Thanks again.

Bubba.

[Adger Smith]

I would be glad to help... yes, I have some ideas why the Pontiac is down on idle oil pressure. I would start with disassembly of the engine.