Looking at an old engine masters contest back in 2007. This yr they were limited to flat tappit camshafts no more then 10.5 compression the same 6500 rpm as always. A 403 cu. SBC won it with 673 hp at 6500 rpm, 581 lbs tq at 5,100 rpm. It used a pro 55 cam core and 1.9 ratio rocker arms. Full right up on the engine because it won. Now of course this is just a few dyno pulls the engine has to last for testing and the event. So no you can't throw 1.9 ratio rockers on a flat tappet run it on the street. But the fifth place engine is the one that impresses me. 498 hp, 6500rpm, 425 tq at 5,400 rpm. This is an engine only 307 cu. (3.00 stroke ) forced to stay at only 6500 rpm, 10.5 compression and flat tappet cam. makes you wonder if the rules were relaxed to say 7500 rpm, 11.3 compression, roller camshafts what this engine builder could have came up with on power. Of course you can always make more power with more cubes that's not the point. Man i like the 302 chevy it just seems right to have another one for me lol.

 

The really interesting engine was the Kasse 404ci Boss with the tiny bore and ultra long stroke: http://blogs.hotrod.com/404ci-boss-f...14-145517.html

A combination such as this is well outside the conventional wisdom. It's not just a matter of displacement.

 

No that's really the norm for what there trying to accomplish highest torque and hp average. When your limited to the amount of rpm you can turn you want long stroke smaller bore. if you can turn high rpms bigger cylinders unshroud the valves better when the engine has less time to get a drink of air and fuel. The 302 is the real oddball in this competition. Then there's Kasse himself his engines have won at least 13 Ihra pro stock championships, won this contest several times.

short stroke big bores have the advantage only on higher rpm engines on lower rpm engines its the other way around they have the advantage.

 

For the most part Engine a Masters motors are "dyno queens" the oil pans, induction systems and headers aren't set up for a real car.

 

and I'm sure their street manners are horrible.

 

Still interesting to see what these builders can pull out of them and the creativeness to get that edge

Dig short stroke motors something cool about them
Spoiled by longer stroke though the power is just more abundant everywhere.

Always lusted for a 69 Z/28 til I drove a few. Sounded good at least.

 

to me the ultimate short stroke engine now is the BBC since they have came out with 4.50/4.60 bore blocks. Person could drop in the 3.76 crank the engine still big enough in displacement to waste any street tire. SBC cylinder bores limits someone to onlystroking to get any power.

Was reading an old mag i have on a record setting 68 camaro 302 super stocker 1970s . they had to use stock heads no porting. the block had to be the 2.30/2.00 two bolt mains. the rules also said it had to use the factory rod with 11/32 rod bolt size ( they used moroso bolts probably good for the time period ) The pistons dome could be no more the 10.84cc had to be same shape on it as factory. The original Z/28 piston weighs 614 grams. The 3.00 length pin 141 grams. There custom piston only had one compression ring weighed 430 grams. They bushed the rod to a smaller dia size. The piston pin was made out of tool steel only 2.25 long pretty thin looking. Pin weight now 51 grams. At the line it turned 9600 rpm made 456 hp. The huge cam was there to help crutch the really bad heads. .050 duration on the cam was 283 lol. car ran 10.25 quarter, with todays heads not a factory mess car would be down in the 9s somewhere with only 302 cu. with a chevy 2 lighter even lower.

 

Popular Hotrodding did an updated 302 with afr 210 heads and hit 530hp at 7300rpm. There was nothing fancy in the build at all. Most of the engine masters motors are not dyno queens. One of the competitiors place his 2013 motor in his car and drag raced and drove it all year. This year he pulled it out of the car and put it in the competition.

My 3.76 x 4.5 stroke bbc made 765hp at the EMC 2014 competition, and 810hp on a dyno in OK. The engine will go into my 68 coupe in a year or two.

Im seriously considering an SBC 377-388 for my afr 245 heads to see if it can make the same hp as an SBC 434 with afr 245s. Im betting it can, but with much less torque.

 

man thats a big head how many rpm you planning with that. That kind of money will buy you a raised runner head

Im considering a 195 head for a high rpm 331 build. Found someone with CNC equipment well respected lot of experience with angle cutting. Next summer going to have him do me a head up with a .125 angle cut.

I have connecting rods to do a 302, 6.250. Is this popular hot rodding artical on line ?

Anytime you want to do RPM on this forum your wrote off as a racer or not a street car.

 

How do you transfer a thread from another forum on to this one ?

 

They would be very easy to drive on the street, that's what the whole contest is about high TQ numbers at low rpms and hp at low rpms.

This contest is not about high rpm narrow power band race engines.

Has to run on 91 octane no more then 6500 rpm.