I thought I'd do a HP thread.

Got a new dream, no longer want to put a mod motor in a stang, it's been done, and I've found a better solution. Al Dart 302 block. Very light and strong.

So I'm aiming for about 500 or close to fwhp, for use in a street-car with power brakes.

Combo: forged 331 stroker (10.5:1 on 98 octane), roller cam, chrome-moly steel roller-rockers, AFR 185 hi-rev heads, 4-into-1 extractors (2.5" dual, X-piped exhaust with staggered flowmaster 40 series)

Induction will be way of fuel-injected individual-runner manifold. Will most likely be getting air from cowl.

Accessories: air-con, ps, a 200A alt, march Al performance pulleys, no fan (will have electric)

I was thinking about using an MSD Coil-Per-Cylinder distributorless ignition.

Parts that will get a low friction coating (if possible, haven't researched fully yet) are: rod pins, piston skirts, cam lobes and bearings, valve stems.

Parts that will have thermal barrier coating are: valve heads, piston crowns, exhaust headers.

Pistons would be vertically gas-ported to use lesser-tension rings.

I was thinking that coupling the fuel-injected individual runner to a fairly agressive roller cam would still give good idle and response qualities, but still give very good power. Add onto that the friction combatants: coatings and rollers, you use less power running the motor, more for the flywheel. Lastly it will have a highish rev limit with the forged, and rollered components, probably set to 7100rpm to 7500.

So who thinks the power goal sounds do-able with that? I think the FI-ind. runner setup will make it possible, give better response from a more agressive cam, and still give big lungs at high rpm.

EDIT: The block would be CNC blue-printed, and parts matched and balance.

Thanks 67p51d! So 205s would be more the go for this setup? Would it be a good head to use, or would it make power at the total expense of driveability?

67p51d: What compression ratio do you run?
What transmission do you have? - How much fwhp do you think your engine makes?


Britt: Thanks for your suggestions, but I don't want to supercharge, I want to keep it NA, and use the individual runner fuel injection with a bigger cam than could be used with a plenum type induction and still get relatively nice manners.

I love screamer motors, it will be part of the car's personality, and will also aid in my efficiency hopes.

I think with good efficiency measures like rollers, and friction coatings, and strong components and stud girdles, and an IR induction, my desires can be met.

I'll probably use 98 octane fuel too, not 95. The V8 Supercar series here has a max engine capacity of 5.0L, and these motors put out 650+ hp on 98 octane premium unleaded. I'm hoping that I can get between 170 to 150hp less out of a 26ci larger motor.

usedtobe 67p51d said:

compresion is low, flat top pistons with 64cc heads I was told that it's around 9.5 but unsure. I wanted to run the car on premium pump gas with out octane booster in socal the highest true pump gas is 91 I still get some deisel when I turn the motor off. the goals that I set for the motor was the most hp I could get with the car still able to run on the street day in day out I don't think that I would want any more cam or carb on the motor. transmission is a tremec... I bought it before the new ones came out it's like a truck tranney too low of first gear the new 500 or 600 trans should be the one to get as foir flywheel horsepower if 18% is the normal loss that would make it 404.7

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Cool! So with an extra 1.0 point of compression, with suitable fuel, the slippy coatings, and a good cam I should be able to get up there.

How is your idle quality 67p51d? If it is lumpy/rough already I suppose I wouldn't be getting a more aggro cam than you have, so won't gain power from that.

brianj5600 said:

I don't know what bore and stroke you plan but, those blocks are available in a larger bore, up to 4.25. The 8.2 block is capable of 385ci, and the 9.5 up to 463ci. Cubes rule especially when trying to retain power brakes and other creature comforts.

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Thanks for replies everyone, and brian, I was going for a 331 combo. I want to keep the small smallblock, for weight and fuel efficiency. I'm not all-out stuck on HP, I mean, if I get near 500, great, mid 400 would be good. I also am concerned with reliable, safe usability. So I want good vacuum for the brakes, and SOME low end. To that end I might get a cam that makes max power at 6500, or 6000, but I'd still like a zinger, even if it isn't MAX power up there.

I'm used to driving a 2500lb 1.6L (30yo celica). I know what no power or (especially) torque is about. I'm sure I'll be happy with probably 4+ times as much torque and power in a car not too much heavier.

I also want the alloy to keep a theme. I want the drivetrain to be alloy, from the radiator, intake, heads, block, oil pan, gearbox case, driveshaft, diff housing, and wheels.

No no, I know a bigger engine will make more power easier, and have more torque (torque is just low-rpm power), BUT they also use more fuel all the time. I don't mind having a motor with the guts (or lack of) of a 6 cyl (well maybe not that crappy, but I like to exaggerate) at low rpm, with power made as rpms rise.

In my eyes the mustang should be a pony car (the classics that is) not a muscle car. Small, light engine with the attitute of a wild... well, stallion I suppose.

I'll have a look at 4.125" bore though, I'd just rather the traditional bore. Are the 4.125" parts more hard to come by than stock bore parts?

I think I'd rather just move up to the 351w block if I were to go for more displacement.

usedtobe 67p51d said:

it idles well, don't forget an alloy flywheel! if I had fuel injection it would be more driveable.I think that if you look at your budget it will be a $20,000 usd motor. by the time it's said and done. those alloy blocks arn't found in wrecking yards ! and if your truly getting one you might want a big bore in it say 4.125 get some!

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I was going against the alloy flywheel, even though logic tells me that rotating mass saps power. I've heard a lighter flywheel kills torque. It logically doesn't make sense, I mean sure it (a heavier flywheel) would give the engine more rotational inertia, but not more torque. Are those things wrong? Is an alloy flywheel better for (streetable) performance than a steel one?

As for cost, I just looked at my file, $31500 - $32500 I think the difference was between a forged and billet crank. well, if I'm going to do it, it's going to be done properly, and I'll always be going "If I had have just waited another few months, I could have got it perfect." if I don't do it right first time. I'm a hard customer to satisfy. It sucks being so picky, but I won't be happy if I settle, so what am I to do? lol

I've looked at suspension and steering, and to a lesser extent bodywork and interior, and susp and steering come to approx 20k, and I'll strip the car myself, I'm sure handy at wrecking stuff. I'm a bit less, but still quite handy at putting it back together too, so I might get some monetary relief from that.

Ok keep the answers coming guys, if I don't challenge my ideals I may just be missing out on something better!