Design your engine

Given a clean sheet of paper what would your ideal engine be.

Here is mine:

Goals. 1) Compact. Dressed 20" length 19" height. 2) V8 crossplane crankshaft sound (classic American V8 burble and thumity thump). 300 hp target with 6500 redline and 7000 fuel cut.

A 3.6-4.0 liter turbocharged 45-60 degree, small 89-91mm bore spacing. 8" deck height, and SOHC valve heads.

The 3.6 Audi V8 has the smallest V8 bore spacing at IIRC 86mm. The SHO 3.4 V8 has the bank angle and 8" deck height Mercedes M117 has the physically smallest V8 SOHC heads

Put them in a blender.

Goals:

1) Very short crankshaft length in order to allow 2 roller bearing mains to be adequate.

2) Very small crankcase volume for good transfer flow with small, low ports.

3) Very low engine rotating inertia

4) 200+ horsepower from 1000cc displacement

5) Unusual sound and power characteristics

Engine: 90-degree case reed valve V3, 77.8mm bore, 70mm stroke. 4600 ft/min at 10000 RPM.

Direct fuel injection, automatic bearing lubrication via pump to mains and hole feed to all rod bearings.

Cylinder lubrication provided by "total loss" feed from bearings and additional squirters under certain conditions.

Intake in front of engine, exhausts all on back of engine. Engine rotates towards back of engine, so as to have the heavy side forces on the piston during combustion push against the side of the cylinders that do not have the exhaust ports.

Cylinders? Baa!

Had to, sorry.

• 60* two cylinder carbon case encased in an extruded alloy stress frame. Design can be expanded by adding paired cylinders and frame extensions allowing anywhere from a 4 cylinder to a 12 cylinder engine. Aluminum cylinder heads with rear mounted VVT enabled camshaft motors. Each case is fully contained and the modular design just requires bolting them together. A torx key at each end of the camshafts and crankshafts allow for expansion.

• Direct injected with combined injectors and spark plugs using a single central port in the head.

• Exhaust "manifolds" on interior of V of head that travels to the rear of the block via a single passage exiting to exhaust manifold outlets

• Intake "manifolds" on exterior of V running forward to air valves.

• Can be configured as a FWD or RWD.

A 4-rotor rotary with the same width rotors as a 12A but taller height like the new 16X with twin sequential turbos, peripheral ports, and direct injection on methanol.

An LSx with BBC bore spacing displacing some 550-600ci with a dual-Dominator tunnel ram, making in excess of 1500HP N/A, hooked to a Lenco.

LSx, forged titanium internals, very large (HE551 size) variable geometry turbo + about 45psi of boost ;)

I don't have to 'design' it, i can build it over a weekend, all parts are readily available...

I like the current LSx engine a lot. I wish it had a lower deck height. 9" is great for rod length but makes packaging in some engine bays tough. An 8" deck height LSx would be fantastic but would limit displacement to the 5.1-5.3 liters mark.

9" is great for rod length but makes packaging in some bays tough.

<---Refrains from saying "THAT'S WHAT SHE SAID!" Ah E36 M3. Nevermind.

4 hayabusa engines "bolted" together to make a 5.2L V-16 that spins to 12000 RPMs and makes a tick over 800HP.

First thought off-hand: 2 variants of same engine: 3-3.5L I6

N/A 400HP @ 10,000RPM, 270lb/ft @ 5000 RPM Redline 11k RPM

TT 600HP @ 8000RPM, 450lb/ft @ 1500 RPM

Fits easily into 240z, BMW 3 series, 350z

3 Rotor or 4 Rotor -Street Ported -9,000+ RPM of revs -Individual Throttle Bodies on a custom intake manifold -~350-400 RWHP

Dropped into my FD chassis RX7 it would probably weigh out to 2,600 lbs wet. Nice power to weight ratio. Someday....

Porcelain block and heads, Forged titanium internals. Roller bearing mains and rods. Electric controlled valves 6 per cylinder. Direct fuel inj. Direct Ignition. Turbo.

200hp 200pf at 1000rpm 500hp 1000fp at max RPM 2.0L

Hayabusa motor with 2 extra cylinders spliced in to make it a ~1950cc I6, designed to bolt up to Toyota W-series transmission and make use of R-block motor mounts; I would bolt it into my Celica and never look back.

Engine for engine's sake, I would love to see an all-aluminum 5-valve V6 in the 2.5 liter range with reverse flow heads, ITBs on the "outside" of the block, and 180 degree header coming straight out of the cylinder valley and out the back of the motor. Or maybe done as a turbo motor, with 3v SOHC heads.

Formula 1 engine with lower compression and a turbo added.

An LSx that revs like an F20C

A straight six with three side draft webber carbs. Duel over haed cam is a must. 300 hp 300 tourq. To me that would be one sexy engine.

Rangeball wrote: An LSx that revs like an F20C

Easy. Take the 5.3L LS4, stuff it with forged bits and the right cam

Volksroddin wrote: A straight six with three side draft webber carbs. Duel over haed cam is a must. 300 hp 300 tourq. To me that would be one sexy engine.

Easy, start with a 4.6L I6.

Next!

I would like to build a flat four, 16v, but like the old offy engines.. the head and cylinders would be of one casting..

Interesting thead...I like Dexter's little inline six in front of a Toyota 5-speed!

Mine would be inspired by the Colombo Ferrari V-12, but updated a bit. Let's go with the classic 73mm bore, 58.8mm stroke for a 3-liter variant, but the smaller bore 2.3 and 2.6 could be nice also. Make both the block and head aluminum, DOHC, but with 4 valves/cylinder instead of the original 2. Replace the row of carbs with a row of little fuel injected throttle bodies, paint the valve covers wrinkle red, rev it to the moon, and enjoy the mechanical music!

Think how much fun this could be in almost anything made on any continent smallish-medium sized, RWD from the 60's-80's begging for an engine swap!

96DXCivic wrote: Formula 1 engine with lower compression and a turbo added.

What he said.

ReverendDexter wrote: Hayabusa motor with 2 extra cylinders spliced in to make it a ~1950cc I6, designed to bolt up to Toyota W-series transmission and make use of R-block motor mounts; I would bolt it into my Celica and never look back. Engine for engine's sake, I would love to see an all-aluminum 5-valve V6 in the 2.5 liter range with reverse flow heads, ITBs on the "outside" of the block, and 180 degree header coming straight out of the cylinder valley and out the back of the motor. Or maybe done as a turbo motor, with 3v SOHC heads.

4v > 5v, ask Yamaha why they went back to 4 on the R1.

z31maniac wrote: 4v > 5v, ask Yamaha why they went back to 4 on the R1.

I don't know the math, but I had always heard that a 5v was mathematically ideal for flow, which was why it was used on the 20v 4A-GE, and several late-model ferrari motors. I emphasize that I don't know the theory behind that, and if it's false, I'm not going to argue elsewise.

I figure Yamaha would go back to a 4v due to complexity and weight reasons, not because of flow or lack thereoft. I would guess that that 5th valve would have to have it's own special rocker arm (whereas you could use the same rocker for all 4 valves in a 4v), and it would have it's own timing issues, both of which increase the cost of the bike and add failure points. I would also guess that it's because advances have allowed 4v motors to flow just as well as 5v motors for all practical current uses, and the benefits no longer outweigh the costs.

Kinda like how desmondromics was awesome for high rpm, until the metallurgy caught up and allowed you to get desmondromic-level rpm with a valvespring. Desmondromics got dropped because it's just extra complextiy and no longer offers enough gain over a valvespring equipped motor in terms of performance to make up for it.

Chevy would probably be a better example than Yamaha, though. Rather than use fancy-pants OHC at all, they've stuck with 2v pushrod motor. And the LS1 crapped all over the Ford DOHC V8 made at the same time. Ford had to add a supercharger on top of that 4v motor just to keep up with a pushrod!

ae86andkp61 wrote: Mine would be inspired by the Colombo Ferrari V-12, but updated a bit. Let's go with the classic 73mm bore, 58.8mm stroke for a 3-liter variant, but the smaller bore 2.3 and 2.6 could be nice also. Make both the block and head aluminum, DOHC, but with 4 valves/cylinder instead of the original 2. Replace the row of carbs with a row of little fuel injected throttle bodies, paint the valve covers wrinkle red, rev it to the moon, and enjoy the mechanical music!

Game, set, and match.

Figure 400+hp at 9000 rpm? And the sound... oh, dear god, the sound.

Easy, it's a 300CID six built by Ford.

Has to be the most trouble-free engine in history.

Good power. Good torque. Iron block and head so there's no "creep" to work the HG loose over the years. GEAR DRIVE TIMING!! no f-ing chain or belt replacement hassles Built for north-south installation only, makes repairs nice and easy. Manifolds on one side, spark plugs and distributor on the other.

I love driving high-strung "toy" engines but if I want a workhorse for every day use and little to no mainenance requirements, the Ford 300 I6 has to be the best one going.

Toyota R-series is probably second.

For a stupid-fun engine, just give me a turbocharged Toyota 18R-G or 2T-G and I'll be a happy man. Gotta love a 30-year-old design that can lay some serious smack on modern engines if given the right tuning.

Shawn

I'd like a 2 stroke. However, I would use forced induction to avoid using a pressurized crank case to fill the cylinder. Give it a 4 stroke lubrication system, because your turbo blows directly into the cylinders. Top it off with a DI system, and it's golden. The power of a 2 stroke with a turbo would be awesome. Having awesome fuel efficiency from the DI system would also be great.

Package it like a Lancia V4 or VW VR6 and it would be pretty sweet.