Highest-revving SOHC automotive engines?

Swank Force One wrote: You know... there was an old thread I remember on mx6.com now that you just jogged my memory. Some of the old timers were talking about how the FET was probably a better motor in many ways. There's something for me to look at.

It does have a superior R/S ratio (1.76 vs. 1.69), closer to what some people believe is the optimum ratio of 1.75. I think it's a shame that it never got any play. However, it doesn't have the big bell housing pattern you need for the FD transmission so I don't think it's in the cards for you. It's too bad, because it is a shorter engine so it should fit under the Miata hood better

I'm not worried about height, actually...

But what I'm wondering about is FET head on F2 block.

Are you worried about breaking rocker arms?

DaewooOfDeath wrote: Are you worried about breaking rocker arms?

Do i think it might happen? Maybe.

Am i worried about it? Nah.

I was more saying i wasn't worried about height because the FE3 has been put in Miatas without huge height issues. It's tight, but doesn't require any crazy hood modifications.

Buddy of mine that spitballed and gave me the idea to do the destroked motor had an F2T in his B2200. Then swapped it out for an FE3, and it ended up that the FE3 was taller, so i should be good.

In light of my other E36 M3 show of a thread...

I suppose i should ask at this point:

Is there actually any real point or advantage that anyone can see, even if only a theory, to the destroked motor that was the subject of this thread?

In reply to Swank Force One:

I have always said no. A short stroke motor needs less air than a bigger stoke motor for the same bore size. It makes the head act bigger than it would on a bigger engine displacement. There are arguments mentioning piston velocity and the like, but there are plenty of giant stroke motors out there running very high RPM to eliminate that doubt.

Swank Force One wrote: In light of my other E36 M3 show of a thread... I suppose i should ask at this point: Is there actually any real point or advantage that anyone can see, even if only a theory, to the destroked motor that was the subject of this thread?

I can't think of any, really. I would be more inclined to stroke it and shoot for 7000 rpm. With good torque, that's already well into more power than you can ever use territory and it will help you spool.

BTW, I was asking about breaking rocker arms because of RPM, not hood clearance, though it is fun to imagine valve float on the scale of hitting it against the hood. ;)

Swank Force One wrote: In light of my other E36 M3 show of a thread... I suppose i should ask at this point: Is there actually any real point or advantage that anyone can see, even if only a theory, to the destroked motor that was the subject of this thread?

No, build the biggest motor the rules let you. Maybe a touch bigger.

I can get about 2.7 litres out of it pretty easily but we're getting into a stroke of over 100mm.

Swank Force One wrote: but we're getting into a stroke of over 100mm.

You wish

Spoolpigeon wrote:

Swank Force One wrote: but we're getting into a stroke of over 100mm.

You wish

I was only making the destroked motor for you.

Swank Force One wrote: I can get about 2.7 litres out of it pretty easily but we're getting into a stroke of over 100mm.

I think this is your answer.

tuna55 wrote: In reply to Swank Force One: There are arguments mentioning piston velocity and the like, but there are plenty of giant stroke motors out there running very high RPM to eliminate that doubt.

Which ones?

My brain sucked there...

I can get up to a 98mm stroke. Leaving stock bore that gets me to a touch over 2.3 litres. If i go to the G6 block i can get just under 2.7 litres out of it.

I'm not sure this is useful, though... since the head is already a restriction on the stock motor.

If the head is going to limit you to 500 hp, I would assume the 2.7L engine will just get you there sooner. Meaning you could spool your humongus turbo at like 3000 rpm instead of 4500 rpm. More area under the curve, right? Or run an even more humongus turbo and keep your 4500 rpm spool and enjoy the better compressor efficiency.

I suppose. What i'm trying to avoid is total "boat anchor" feel in the front of a Miata, though.

Which is why i was thinking of the destroked motor in the first place. Rev more like a BP or better, make power like an F2. Win/win.

Screw it all and do a Hyundai beta swap!

DaewooOfDeath wrote: Screw it all and do a Hyundai beta swap!

I'm not real big on stepping back when it comes to engine swaps.