7500 RPM 302 Stroker Suggestions

[Buzz]

Originally Posted by xb-60

Very light car....small, high revving Windsor

This is spot-on within the context of this thread. If we're talking about small block Cobras, don't forget that they weigh a bit over half of what the average '60's / '70's American muscle car does and the addiction to big-inch, big-torque, low end luggers originated with the need to make these behemoths get up and move in a similar fashion to "true" (read that "smaller/lighter") sports cars; generally of the European persuasion, that satisfied generations of drivers using much smaller, higher-revving engines.

"Move" in the preceding sentence means only in linear terms, because no amount of torque and low-end grunt could overcome the laws governing changes in direction of a massive object rolling on skinny, bias-ply tires. The little sports cars were still plenty of fun and generally faster on any road that wasn't dead straight and 1320 feet long.

Having said all of that, the OP never said that this engine was going into a Cobra. "Trans Am inspired build" implies to me he may be thinking about a Mustang but even if that's the case, a Trans Am inspired 1st gen Mustang gutted for racing performance would still be a relatively light car.

[MKS427]

408 stroker is a great budget build, without going to a Dart block. You can build it for torque and reliability for a reasonable amount of $$$. For an extra 3-4K you can go with a Dart 427/445 at sub 600 torque.
Someone mentioned using B Lykins or others. My 2 cents, known engine builders will have the experience to know the package works, will do it for less $$$, and will include a warranty on just about anything that runs on pump gas.

[MKS427]

Follow up: IMHO, If you go with a 7500 rpm street engine it will better suited for the track than the street. With 7500, you should invest in T&D shaft mounted rockers, $$$$$$$.

[eschaider]

The majority of car owners on this site do not have 289 powered cars. Their engines range from 400 to about 500 cubic inches and larger for a reason. While the idea of a small displacement high revving engine possesses a certain romantic aura and tug on our heart strings, the simple fact of the matter is the vast majority of the car owners opt for displacement increases so they can enjoy that solid kick in the seat of the pants that is so intoxicating, at almost any speed.

There is one site member that used an FR500C Ford competition engine for his first car. The engine could easily exceed 7000 rpm by a wide margin and it made somewhere between 450 and 500 hp. After two or so years he sold the car and built a new car this time using a 482 inch FE for power.

The romance of the all conquering, high performing small block 289 of years gone by, has gone by and for good reason. Today there are better alternatives for the non competition driven replicas we all have today. The preponderance of the owners have voted with their wallets and the winner was larger displacement lower rpm engines which by the way require less maintenance to maintain those performance levels. By the way I believe the highest performing racing creation on the site here is Morris' 427 FE powered Kirkham which I believe uses a 482 inch FE.

In the end it is your car and your money, which makes any decision you make correct at the time you make it. However, just like so many who have had that same gleam in their eyes for the romantic small block that revved so high and won everything in sight a half century ago, you need to remember that was a factory backed, factory maintained effort a long time ago. Today we have even better alternatives available to us that make much more financial and performance sense.

[incoming]

I'm sorry but i'm a realist.

It doesn't matter what we do to our cars trying to be purists.

We can't outrun a teenager with a chipped Mustang bought by mama?

We do look way cool though.

[Dominik]

Originally Posted by incoming

I'm sorry but i'm a realist.

It doesn't matter what we do to our cars trying to be purists.

We can't outrun a teenager with a chipped Mustang bought by mama?

We do look way cool though.

We can still outrun them, but I know exactly what you mean. Time caught up with us. That's why my last engine was a 390 FE with moderate cam.

[Tremelune]

I've been trying to research building an engine like this. The biggest limiter seems to be valve float. 302-347 will all rev the same these days, though I don't know if the stock block is up to it. It seems easy to find heads that will rev to 6500, but hard to find heads that will rev higher. I see a forged crank and pistons recommended a lot. I've read there are hydraulic lifters that will work, but it may have been a fever dream since everyone recommended solid. Well-balanced internals; and light never hurts...Don't forget that you'll need a transmission that will handle it too (TKX).

The Ferrari 250 Spyder had something like 240hp at 7,000rpm with a 5,000rpm torque peak. The Jaguar E-Types had similar power with a torque peak slightly higher. Those are fun engines, and my car will see a lot more mountains and canyons than stoplights. Some like to feel G-forces from a dig, and some like to wind a smooth engine out for turn after turn, shift after shift.

[CowtownCobra]

If you are so into hi rev's, build a Cleveland

[Alfa02]

There's a old saying "Nothing beats Cubic Inches" true today as it was back then. also, Torque is KING, as is you're in the torque range much more than the Horsepower range. we have in the hanger a West Coast Cobra, with a Cope Bros. built SVO 514 (609HP @5600RPM), that will "Chug" pass my high revving 347 (551HP @7200RPM) Pacific Roadster, all day long, again with the rear tires being the limiting factory, but I like it that way, much cheaper to replace tires than anything else in the drivetrain. My #.03 Cheers Tom.

[Streetwize]

The 363 is a nice combo for the 8.2 and even with a decent head like the Trick Flow 11R or the AFR 205 and a ported victor jr you should have ZERO problem hitting 7500 with small solid roller cam, Hydraulic cams can rev past 6500-7000 but a nice endurance type solid roller has a lot less mass and will be quite a bit snappier. But (if it were me and I was going to road race it at the track) I'd prefer the 3.25" stroke with the same 5.400 rod over the 3.4" stroke, which works out to almost 348 cubes, the lower piston speed and a better rod ratio is your friend at 7500 rpm all else being equal.

But for me the best combo would be a 9.2 Dart (Cleveland deck height) with a 4.125" bore and a ~3.70" stroke and with a long 6.125" or 6.2" rod using 2.0" (327 SBC size) rod journals with CHI heads and manifold. That would be more of a week-end 'run & gun" motor with at least a 3.90 gear and an overdrive....but you could still make plenty of power with a twisted wedge or AFR head.

396 cubes that would still rev to 7500 easy with a bobweight about as light as about the same rod ratio as a 331" 8.2 deck and assuming you go aftermarket block, really won't cost much more.

363 cubes will still move a 2500 pound car very quicky, the "trick" is to put plenty of head on it with strong mid lift flow but not so much port volume and cam to make the bottom end lazy. Compression is torque so even a 331 properly set-up will still get your attention at 2800-3000 rpm. My rule of thumb (assuming you build with adequate compression) is if you can get about 265 cfm at .450 lift you can make 500 hp pretty easy regardless (within reason) of cubes. So the smaller the cubes....the smaller the intake port CC will give you the best upper bottom and mid-range torque at a relatively small trade-off of "bragging rights' top end hp.