7500 RPM 302 Stroker Suggestions

[bapapp15]

Hello!, As the title says I'm looking to build a 302 Stroker capable of 7500+ RPM at 450ish horsepower. The car will be used occasionally on the track, for autocross, and spirited driving on street come weekends. I've never built an engine on my own before, let alone something like this so I was hoping someone here might have some information/experience to help point me in the right direction. Money isn't an object as I'm looking to do this right the first time.

As for right now, I was looking at using Ford Stroker's 331 Liberator Dart Shortblock for the bottom end, with the Scat Cranks and Rods(or should I upgrade to the Callies magnum crank+ Oliver light rods?), flat top pistons, and the inline valve relief. For heads, I was looking at Stage 2 Canfield 192 cc with 58 cc combustion chambers, paired with Ferrea intake and Mahle exhaust valves, beehive springs, and titanium retainers. I am still unsure what style of camshaft, lifters, intake, or what compression ratio I'd I'd like to run (Suggestions are welcome).

Are these the right parts for the build/could they theoretically handle 7500+? I'm worried I might need a lighter rotating assembly, and with the pistons working with the Canfield heads. If anyone has used Ford Stroker and CPR I'd also be interested in hearing about it.

OR

If anyone has an engine builder they could recommend, I'd consider going that route instead.

Thanks!

[eschaider]

Why are you choosing a 302 displacement and why is a 7500 rpm operating speed important to you?

[bapapp15]

Trans am inspired build, those are about the numbers they hit back in the day.

[LG57]

Just talk to Brent Lykins and be done with it. He can help you with all the things you mentioned or even build the motor.

[eschaider]

The metric that moves these cars and makes them fun to drive is torque. Unless the engine is supercharged the 302 displacement is going to be a little light in the seat of the pants dyno space. This usually results in a new and larger engine or a new car purchase.

That said, it is worth noting that the all conquering Cobra legend was created with 289 inch engines. It is also worth noting that, that was then and this is now.

With the availability of aftermarket everything for the Windsor platform there is no reason you can not produce a very frisky 427 (or larger) Windsor engine for your car at essentially a push price wise. Visually they can be indistinguishable however the moment you let out the clutch on the big inch version you have an extremely different experience.

The old TransAm legends and performances were great on the track but not so much on the street. The large port heads ran like crazy upstairs and were not as well suited to the proletariat style of driving that non track days enforce on us.

In the end this is your call exclusively. That said you did solicit opinions. I suspect others will also encourage you to explore a larger displacement alternative before this thread is over.

[eschaider]

Follow on thought,

Most new Cobra owners will be wowed by the car performance and behavior, irrespective of which engine is in it. As you begin to get acclimated to the car you always wish you had built for more power because you become accustomed to what the engine can produce — one more thing to think about.

[jasond29]

The question I would ask is do you want it to be 302ci or do you want a dimensionally the same size as a sbf....(8.2 deck/ 9.5 deck)?

I went with Brent Lykins and got a 8.2 deck block but its an aftermarket block (4.125 bore)....363 final cubic inch. Can spin to 8k.

Rpms is mostly about valvetrain stability.....needs to be light....will cost money, a good bit.

[Tommy]

bapapp15,
If you know the pluses and minuses of living with such an engine and you're willing to tolerate its shortcomings on the street, then Brent Lykins can build it. But I urge you to pay attention to those who have learned what its like to live with a race engine the hard way. Generally speaking, engines optimized to operate up to 7500 RPM are not much fun below 3500 RPM, which is where you'll be 95% of the time on public roads. More than a few hotrodders have paid a lot of money for engines that are more fun to brag about than to drive.

[twobjshelbys]

Originally Posted by Tommy

bapapp15,
...
Generally speaking, engines optimized to operate up to 7500 RPM are not much fun below 3500 RPM, which is where you'll be 95% of the time on public roads. ...

Agreed. I found that the engine wasn't happy running at lower RPMS and spent much of the time in lower gears at higher RPMs - 3rd most of the time on the street. It just felt like the engine was asking me to blow the cobwebs out.

[Grubby]

I suggest discussing your wants and needs with a good engine builder and getting suggestions. I used Brent Lykins who frequents this board.

He asked lots of questions about how I planned to use my Cobra and built to match.

He could sell you parts to build the way you want or build for you.

John

[CHANMADD]

Originally Posted by Tommy

bapapp15,
If you know the pluses and minuses of living with such an engine and you're willing to tolerate its shortcomings on the street, then Brent Lykins can build it. But I urge you to pay attention to those who have learned what its like to live with a race engine the hard way. Generally speaking, engines optimized to operate up to 7500 RPM are not much fun below 3500 RPM, which is where you'll be 95% of the time on public roads. More than a few hotrodders have paid a lot of money for engines that are more fun to brag about than to drive.

Trailer cars.........Been there ...my current motor has reduced compression and cam.

[Dumpling]

Most racing series attempt to LIMIT power and performance, attempt to keep everyone on an equal basis power-wise, making (theoretically) the driver's skill the determining factor in the outcome of the race.

I can't imagine any driver, Trans Am or otherwise, saying "I've got enough power in this car, it's enough".

Why don't you want as much performance as you can wring from whatever engine family you choose? Bore it, stroke it, cam it as big as you're willing to put up with. JMO.

[Mark O'Neal]

Originally Posted by Dumpling

Most racing series attempt to LIMIT power and performance, attempt to keep everyone on an equal basis power-wise, making (theoretically) the driver's skill the determining factor in the outcome of the race.

I can't imagine any driver, Trans Am or otherwise, saying "I've got enough power in this car, it's enough".

Why don't you want as much performance as you can wring from whatever engine family you choose? Bore it, stroke it, cam it as big as you're willing to put up with. JMO.

All you need is enough power, after that it's chassis and tires.

I can easily build a 3,000 horsepower motor for your Cobra, but you wouldn't be able you use it.

[MKS427]

Originally Posted by Mark O'Neal

All you need is enough power, after that it's chassis and tires.

I can easily build a 3,000 horsepower motor for your Cobra, but you wouldn't be able you use it.

A LOT of owners go cheap on the tires. That negates all the effort and money put into the powertrain and chassis. Spend for the Avons or R888Rs.

[xb-60]

Originally Posted by Dumpling

....I can't imagine any driver, Trans Am or otherwise, saying "I've got enough power in this car, it's enough"....

Haha.... that reminds me of that quote of Mark Donohue's ....

"If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower."

Cheers!
Glen

[Mark O'Neal]

Originally Posted by Dumpling

Most racing series attempt to LIMIT power and performance, attempt to keep everyone on an equal basis power-wise, making (theoretically) the driver's skill the determining factor in the outcome of the race.

I can't imagine any driver, Trans Am or otherwise, saying "I've got enough power in this car, it's enough".

Why don't you want as much performance as you can wring from whatever engine family you choose? Bore it, stroke it, cam it as big as you're willing to put up with. JMO.

We built a pair of motors for Shelby when he was looking at running a sort of IROC series with Cobras. They went to Las Vegas for Mario Andretti and A.J. Foyt to do testing. They told them that we'd have to pull some power out if they wanted them to drive them.

My street Backdraft car made more power than those did.

Incidentally your third sentence conflicts with your second.

[eschaider]

I think the OP will be OK. As long as he uses a good set of 5.57 gears in the back and keeps his daily driving rpm between 5500 and 7500 rpm this is likely to be an engine for the ages.

[bapapp15]

Thanks for all the suggestions!, I'll get in touch with Brent shortly.

[Harpoon PV2]

289 Cobras were quoted as having 271hp at 6,000rpm and 312lbs ft. 3400rpm on 11.00 compression! You can buy a 5,0L cast iron roller rocker engine with 9.0 compression that is advertised as 300hp, not sure what rpm, but I am sure high enough! This is at Summit, but pretty much all the good builders can meet that. Funny note, after the 1965 FIA Class III win, Alan Mann talked about how much he hated the 289, because it broke when pushed above 6,500 rpm. He went on and said, "it was a lousy engine, the 289, and basically unreliable, though $250,000-worth of development would have made it a world-beater." I think if he should have added another zero, that's probably what Ford spent to make the 302 into one of the best engines of all times!
One last note, I have never meant anyone who drove a small block Cobra in the 60s or 70s who looking back complained about the lack of power, that includes me! We all just smile with that far away look of someone remembering their first love! Cheers, Dennis

[xb-60]

Originally Posted by bapapp15

.....I'm looking to build a 302 Stroker capable of 7500+ RPM at 450ish horsepower. The car will be used occasionally on the track, for autocross, and spirited driving on street come weekends.....

To the OP, I quite understand where you're coming from here. The original 260 and 289 Cobras race cars, and to a lesser extent, the small block street roadsters, had high revving engines with an emphasis on top end power. What's wrong with wanting to emulate that in a replica small block Cobra build? Sure, it won't have a lot of torque in the low and middle rev ranges, but if the power is there at the top end - and that's what the owner wants - what's the problem with that? If it's a bit flat in the lower rev range, it had compensations at the top end. What's a nice shifting gearbox for anyway?

In my own original engine planning, and before the reality of what was able to be road registerable where I live became clear to me, Brent Lykins and I exchanged many emails regarding engine specs. I wanted an engine that would develop max power at around 7500rpm and the bottom end torque didn't particulary matter. Very light car....small, high revving Windsor ....I didn't see a problem. If I was able to do that legally, that is still what I would want to be doing. Anyone can have an engine with plenty of low down muscle, but that's not what everyone wants, and it's not what the original small block cars were like.

Cheers!
Glen