BBC dirt track modified engine

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BBC dirt track modified engine

Post by Truckedup »

A friend is considering getting into the Big Block dirt track modified class. This is North east rules....He has a 454 Chevy from a motorhome and about $6000 to spend on the engine.....The rules aren't too strict...Cast iron block , OEM , Dart or Merlin replacement blocks, 467 cubic inches maximum ,steel rods and crank, any two valve "conventional"iron or aluminum heads and can be ported. No titanium parts. Cast aluminum intake of any brand that will fit legally under the hood scoop, it can be modified. Holley 4 bbl center section , any type metering blocks, Roller of flat tappet cam, magneto or HEI..Mandated fuel is VP 113 leaded..Car weight is 2500 pounds...Good ones make 800 HP...He figures 650 Hp should be competitive for his current driving skills...
Will 6 grand build a reliable 650 hp engine if he finds parts at the best prices?
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Re: BBC dirt track modified engine

Post by BILL-C »

What tracks does your friend plan on racing at?
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Re: BBC dirt track modified engine

Post by Truckedup »

BILL-C wrote: Sun Jul 15, 2018 7:55 pm What tracks does your friend plan on racing at?
Canandaigua, New York, 1/2 mile slightly banked dirt...pretty fast track...There's also a few other tracks in the area He runs a stock class car right now.
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Re: BBC dirt track modified engine

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Re: BBC dirt track modified engine

Post by BILL-C »

The typical Northeast BB modified has 720 tq and 850 hp. They have very lightweight rotating assemblies, and 18* heads with small raised oval intake runners and very high velocities for great torque and throttle response. You will just be in the way with an engine like what you are looking to build. You would be better off buying a used complete, slightly outdated ,engine from one of the bigger teams.
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Re: BBC dirt track modified engine

Post by englertracing »

discard the chevy
build a ford 460 with kaase boss 429 heads
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Re: BBC dirt track modified engine

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Re: BBC dirt track modified engine

Post by Truckedup »

BILL-C wrote: Sun Jul 15, 2018 10:06 pm The typical Northeast BB modified has 720 tq and 850 hp. They have very lightweight rotating assemblies, and 18* heads with small raised oval intake runners and very high velocities for great torque and throttle response. You will just be in the way with an engine like what you are looking to build. You would be better off buying a used complete, slightly outdated ,engine from one of the bigger teams.
Yes, 650 HP might not be enough...But there are cars with 800 HP engine cars that get in the way due to handling problems and or driver skills.. You all do make a good point about buying a used engine and I think that's what's going to happen..
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Re: BBC dirt track modified engine

Post by nitro2 »

Truckedup wrote: Sun Jul 15, 2018 8:12 pm
BILL-C wrote: Sun Jul 15, 2018 7:55 pm What tracks does your friend plan on racing at?
Canandaigua, New York, 1/2 mile slightly banked dirt...pretty fast track...There's also a few other tracks in the area He runs a stock class car right now.
That's a huge jump, street stock to the top modified class on one of the bigger tracks. There are guys with 20-30-40 years experience and a bazillion wins running that class. There are plenty of good runners in the small block modified class that would not do well running a big block car against those guys. What about running the lowest Modified class first (Sportsman) for 1/2 year or a year to get a feel for that type of car, before jumping in with the big boys in the top class ? Just a suggestion.

Then there are also 305 sprints. Probably a fair bit cheaper in the end and even though a sprint car is technically more challenging than a Modified, some people's brains are just geared to the style of driving for sprint cars, rather than Modifieds. If he ever plans to eventually run sprint cars, stay out of the Modifieds altogether, he'll learn things in Modifieds that have to be unlearned when going to Sprints and lots of guys fail at that unlearning thing. My 2 cents :)
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Re: BBC dirt track modified engine

Post by Truckedup »

Yes, I also think it's a big jump...He's said to be an excellent driver, maybe a "natural", and does very well against better cars..I don't know much about this type of racing other than going to the track last Saturday....What they call "stock" looked to me like cut down G body Malibu's on some sort of frame, probably a restricted 350 engine? But they flew around the track on three wheels...The Big block Modified were more rowdy and very loud..The 305 Sprints looked more controlled with quick precise movements...The track was rough and the heats all had one car pulling out ahead of the others for the win..it all looks very addictive and I don't really want to get sucked into the young man's dreams.. :D
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Re: BBC dirt track modified engine

Post by billet »

First thing I will say is:

If he's only willing or can only afford to spend 6K or so on an engine for that class, he might want to rethink his moving up a class. Now if he's just wanting to buy or spend a little to see if he likes it or get some seat time in the new class, fine. However, just make sure he really knows the cost of those upper class's.

Having driven, owned, and been part of several regional/national championship winning Late model teams over the years, it's gotten stupidly expensive and driven most of all of us out of the sport unless you just very wealthy or have a rich sponsor or car owner. When I got out as a car owner, it was costing us 1200.00 to unload the car a night and we had really sweet engine deals that don't happen anymore and that was about 10 years ago.

Just make sure he understands the expense he's looking at before jumping head first.

On a side note, depending on track. Today we rarely use more then 50% throttle come feature time (900+ HP), so if the track is always slick don't overly worry about HP just get something smooth and controllable while he learns the new cars.

Remember racing is supposed to be fun...
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Re: BBC dirt track modified engine

Post by fdicrasto »

Totally agree with nitro2, go to sportsman and learn this type of chassis with a small block, 2bbl engine. Been awhile since I was involved but going out there with little experience and way underpowered could be very costly in many other ways. At least a season in a sportsman car then decide on the bbc modified jump. It won't be a wasted year and the transition to the modified car will be much smoother and rewarding.I also agree with trucked that this can be very addicting. I was a dedicated drag racer and when I got involved doing engines for sportsman, modified sbc and bbc for some Canandaigua racers, I found myself skipping many Saturday night drag events with my piece and working on my round rounders cars instead.
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Re: BBC dirt track modified engine

Post by leahymtsps »

Truckedup wrote: Sun Jul 15, 2018 7:41 pm A friend is considering getting into the Big Block dirt track modified class. This is North east rules....He has a 454 Chevy from a motorhome and about $6000 to spend on the engine.....The rules aren't too strict...Cast iron block , OEM , Dart or Merlin replacement blocks, 467 cubic inches maximum ,steel rods and crank, any two valve "conventional"iron or aluminum heads and can be ported. No titanium parts. Cast aluminum intake of any brand that will fit legally under the hood scoop, it can be modified. Holley 4 bbl center section , any type metering blocks, Roller of flat tappet cam, magneto or HEI..Mandated fuel is VP 113 leaded..Car weight is 2500 pounds...Good ones make 800 HP...He figures 650 Hp should be competitive for his current driving skills...
Will 6 grand build a reliable 650 hp engine if he finds parts at the best prices?
Just a few personal observations
There are those running stock blocks mostly because they weigh less than the lightened aftermarket ones (but eventually they all crack)
Certain valve train parts can be ti.
D12 is also legal
650 h/p is easier to learn to drive than 850 and that would let him focus on learning chassis setup
Tire management is a big thing with these
You do know these are dry sump engines right? $6000 won't get you much, better to find a good used eng. if he can afford it

Tom
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Re: BBC dirt track modified engine

Post by Newold1 »

I am with what most others are telling you here. If your friend cannot at a minimum DOUBLE his $6K spending on his big block engine then he should move his efforts to another class and not waste his $6K and frustrate himself.
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Re: BBC dirt track modified engine

Post by Truckedup »

leahymtsps wrote: Wed Jul 18, 2018 6:41 am
Truckedup wrote: Sun Jul 15, 2018 7:41 pm A friend is considering getting into the Big Block dirt track modified class. This is North east rules....He has a 454 Chevy from a motorhome and about $6000 to spend on the engine.....The rules aren't too strict...Cast iron block , OEM , Dart or Merlin replacement blocks, 467 cubic inches maximum ,steel rods and crank, any two valve "conventional"iron or aluminum heads and can be ported. No titanium parts. Cast aluminum intake of any brand that will fit legally under the hood scoop, it can be modified. Holley 4 bbl center section , any type metering blocks, Roller of flat tappet cam, magneto or HEI..Mandated fuel is VP 113 leaded..Car weight is 2500 pounds...Good ones make 800 HP...He figures 650 Hp should be competitive for his current driving skills...
Will 6 grand build a reliable 650 hp engine if he finds parts at the best prices?
Just a few personal observations
There are those running stock blocks mostly because they weigh less than the lightened aftermarket ones (but eventually they all crack)
Certain valve train parts can be ti.
D12 is also legal
650 h/p is easier to learn to drive than 850 and that would let him focus on learning chassis setup
Tire management is a big thing with these
You do know these are dry sump engines right? $6000 won't get you much, better to find a good used eng. if he can afford it

Tom
Rules say wet or dry sump but I can't imaging a wet sump engine being a good choice...He's still in the thinking stage but you and other suggestion of a used engine seems best...
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