Or, you could use one of Tom Cloutier's designed "Crossover" header systems. That turns the uneven, side to side, firing 90 deg crank V8 into the sound of a flat plane crank V8. It does sound like a Ferrari. No more rumble. Smokey Yunik experimented with flat plane vs 90 deg cranks on Chevys a long time ago and eventually concluded there wasn't enough performance difference to go to the trouble.

 

Bump

Wonder is this got off the ground. Being a pragmatist, I'd always thought the best reason to do this is to open up the world of 944 heads and cams to the 928.

With a 180 degree crank, the 4 cyl cams have the proper timing.

I've always understood that the 928 cam design limited lift.

Wouldn't it be fun to adjust all those mechanical lifters (yikes)

Dan
78 5 speed

 

Bump

Someone needs to do this, just to see what happens. I say try it with a 4.5 or 4.7 with CIS, and see whatcha got!

 

I was talking to another renlister about this topic a little while ago, in this discussion 5 litre quad cam version.

 

really, you could just use 944 or 968 cams to do this?
would the engine be more or less balanced due to the flat crank?
would it really sound like the ferarri that way?

how cool would that be if it did .

any advantages performance wise?? is the lift on the 944 or 968 setup, higher?

 

That engine may make more horsepower but it would have less torque

 

Well, as we all know, more HP means more torque (at the wheels) too.... We all know that they are related!

 

I would happily give up some torque for a bump in horsepower and that noise! Then perhaps people wouldn't think the car has a chevy small block in it! (Some very dangerous and irresponsible driving in this video, but enjoyable nonetheless!)

 

Anyone that is serious about doing this should really research the 2016 Ford Mustang GT350.
The new engine is a 5.2 liter with a flat plane crankshaft.

Twin Turbo Todd designed his engine to go upwards of 8,000rpm and all of his testing led to a very precisely balanced motor with super light pistons / connecting rods and very stiff valve springs, much stiffer than any OEM Porsche springs he's aware of.


Simply building a flat-plane crank with 944 cams is not going to duplicate the 355 or any Ferrari sound and power curve.
The differences in the design of these engines is significant.

I've had the pleasure of taking apart a 355 and spent a lot of time behind the wheel.

The 355 also has:

• Individual throttle bodies
• very short intake runners (at least compared to a 928 intake)
• 5-valves per cylinder
• Tuned equal length exhaust manifolds
• Two stage exhaust that "opens up" at higher RPM's
• A radical cam profile (compared to the 928 or 944 camshaft) tuned for the high RPM

 

Off topic, but I so want a 355 in the stable next to the 928. Probably never happen, but that's the fantasy...

 

I don't think any of those things effect the sound all that much, however, its the reason the 355 can make 400hp out of a 3.5 liter v8.
the only thing that could be different for that sound is the exhaust opening timing of a flat plane V8. high lift cams don't make much of a sound different, at WOT, we are at WOT, so two stage exhaust doesn't matter at all, and some of use have a pretty nice set of equal length headers.

so what is the main difference if not the flat plane crank ?

 

The 355 sounds unique compared to other V8 Ferrari's due to the 5-valve design.

As for cams......the point I was trying to make is no "drop in" cam (944 or otherwise) is tuned for such high RPM's so it's not going to sound the same using a stock cam versus one tuned for the higher power band.

The intake will also make a huge difference. The stock S4 intake is hardly designed for whatever the new firing order will be with a flat plane 928 engine.

Exhaust tuning is a huge key for sound no doubt, but as Greg has graciously shared in his headers threads, it's not all that cut and dry designing headers for the best power, much less that "exact" sound.

Someone brought up the "cross over" headers once available for the 928. Years ago at an OCIC, Mike (aka Z) spent most of the day on the dyno with Louis Ott tuning his car with Devek L2 headers and an almost identical car with the cross over headers.
At the end of the day, Mike's car make the best power with the Devek units vs the crossovers.


I think doing a 180 engine in a 928 would be cool just for the sake of doing it, for someone that has an unlimited budget and just wants to do it.
To do do it right, by the time you are done the only part left of the original engine will be the block and heads.
Designing the intake alone will push the envelope of most budget's, even using "off the shelf" units like Simard's ITV's. Look at all the work that went into Louie Ott's intake.

 

again, I don't think the intake or the cam has much to do with more than, how much power it makes, or how lumpy the idle is. the sound is in the headers.... there was a more even tone to the equal length headers and it was a radical change. not earth shattering difference , but different.
Anderson put on an intake with short runners, two TBs and the sound was the same as well. we all have heard the ITB 928 engines as well... still sound like 928s. so, where is that sound coming from???? again, still think its in the exhaust timing for the v8 flat plane.
the Ferrari engine makes the sound at idle, 3000rpm, 5000rpm and 8000rpm. grossly different than the 928 or any other v8. that's why im wondering if there are any other flat plane engines out there what do they sound like. sure, the cams of the 944 or 968, might be better than what we have, but are not tuned for 8000rpm, I agree. in fact, our power falls pretty rapidly after 6500rpm. but even with new cams , designed for RPM ranges of 8000rpm, we would need an entirely different designed engine.
ferarri is getting 450 to 500hp out of a 3.6 liter. yes, much shorter stroke but most of the gains are due to the intake.... not much different than why the Gt3 makes 500hp out of a 3.8L but only a 6cyl. is the 911 flat plane crank?

 

Funny...the 355 in my garage doesn't sound that way at 3k, 5k...or at idle.

The sound at high RPM's when the cams really come on is when they scream that Ferrari sound. Drop in a cam not tuned for that range...it's not going to sound the same.

At idle, the 355 doesn't sound impressive at all, rather mundane.
It's the same at cruising speed. On a past cruise the 993 driver behind us noted it sounded more like a model airplane when putzing down the highway. He's a good friend so he knew he wouldn't offend when he said: "It sounds horrible at cruising speed".

I never said the firing order played no part in the sound, I never even hinted at that idea and yes it's the biggest factor is why those cars sound the way they do.
I'm simply saying the overall package is what makes a Ferrari sound like that, it's not just ONE thing.

If it's just the crank, then why does the 2016 Ford GT350 not sound exactly like a Ferrari?

In my humble opinion, slapping a 180 degree crank in a 928 with 944 cams using the stock intake and currently available exhaust pieces will not make a 928 sound like a 355 Ferrari.

Also...... if you go back and re-read my post, the list I made was directed towards not just the sound but also the power band. Taking my "list" and only discussing the sound is only half the discussion.

 

I think a lot of cars sound great at 6600rpm, like my motor! but not that impressive down lower at near 4000rpm. I just drove an F1355 and I think they sound great at any RPM. a little like a high strung 4 banger motorcycle. very smooth and a higher pitch sound to them.

anyway, is there a firing order that could be involved too? or do all flat crank engines have the same firing order?

anyway, when I pass a ferarri , I always roll down the window to listen to the song. you have to be a freak to not like that sound, even at cruise.
maybe I like model airplane noises.

as far as mustangs, the Boss 302.. did they have the flat crank? they are reving past 8300rpm now. they sound wicked.... but I think the 928 motor would sound even better at 8000rpm.
https://www.youtube.com/watch?v=Pj-5...ature=youtu.be