A 32 mm valve was used you say, I'll mull that over. First thoughts would be the increased valve size will need some serious metal removed which is difficult from what I was looking at on the SSR. The size might well be possible but at the expense of what.

In regards to being potentially a better ultimate power engine than the 4cyl I'd have to disagree, rpm will sort that out easy enough, the 5 cyl just won't do high rpm like the 4 cyl will.

I have read here of them revving to 8000 - what do you rev your 16V to?

The 4 cyl is known to go past 10k, a lot of 4 cyl engines do whereas I've never heard of a 5cyl coming close.

Maybe - but what do you rev yours too?

The 5 cylinder engine has a shorter stroke so, with solid lifters, would be safer for higher RPM than the 90mm stroke of the 16V engine

By the way, that's a mean piston speed of 30 metres/sec, peak piston speed of 49 metres per second and maximum piston acceleration of 4075G - how long do they last?

Sure - but the inlet port looks long and slim, more geared toward lower valve lifts and mid range torque. If it can be made to compliment a high lift cam ie; bpf and peak lift intersect at 'some' point there is a case for that.

The 5 clyinder has a natural un balance regardless of stroke or rod length, a 4 pot is'nt ideal either mind .

Overall length of the inlet tract - including the ports, manifold etc, is what determines the rpm range, isn't it? And GC said you can take 2mm of metal 'from anywhere' on the head, so the ports can be made significantly bigger if required it would seem.

I don't, too impoverished to finish my money pit ATM, so many other projects and short of winning the lottery it will take a while yet. How hard do you rev yours?

2 mm is barely enough to cater for the standard valve let alone making it a fair bit bigger.

Find an example of a 5 cyl doing big rpm, I can't.

That stuff influences the engines sweet spot but it's the engines assembly that allows it to survive it. At high levels servicing needs to be frequent but it helps if there's something to service.

Fiat Uno with a Stilo engine
http://www.youtube.com/watch?v=jQm8HVxHQm4
http://www.youtube.com/watch?v=FKGQ1eHm0qQ

I'm just on my phone so it's a struggle to see what he revs to, does he go past 10k?

8500, but although I still have full boost at that speed the power peaks at 7500, so not much point in revving it higher unless to save a gearchange.

I'm not sure what would need to be done to shift the peak power higher if I wanted to. More radical cams I suppose, but then I can't find any cams more radical off the shelf.

No idea, but I know it's a high revving 5 pot engine As for the 10k rpm, wasn't that Greg in Greece where he has de-stroked it to run a 1.8 to give him the revs?

So its an unknown other than not really being ultimate effort.

That's often how they buzz the 4cyl's that high, not always but often.

I thought you were building a 16v engine?

"Overall length of the inlet tract - including the ports, manifold etc, is what determines the rpm range, isn't it?"

No, only on atmo engines. On pressure-charged installations, it's not a factor at all in the power curve (except off-boost. In terms of power output however the longer the inlet tract the higher the viscous losses & the more boost is needed to overcome them - the very losses we're trying to eliminate with head work.

G

Yes - that's what I am talking about.

I have read this thank you Ferrarist

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=1246353#Post1246353

is there a photo hosting service that opens quickly and is junk/advert free?

G

Ah, yes. I forgot your theory that sound waves don't travel through air more dense than one atmosphere.

imageshack leaves me alone though it is a fiddle.

You may use uploadnow.org or uploadup.com
No need to register, when image is uploaded, just copy the image URL from "Direct Link" field, and use it here.
Hope that's help......

"Ah, yes. I forgot your theory that sound waves don't travel through air more dense than one atmosphere"

Martin do give it a rest. That is not a theory I ever put forward.

The reason why inlet tract length does not have any influence on power on a pressure-charged unit under boost is that the cylinder in a state of depression sees overpressure right at the inlet valve whereas on an atmo unit the primary wave (negative) travels up the inlet tract and is only reflected when it sees atmospheric pressure (eg: at the rampipe exit). There is NO such beneficial inlet wave activity in a turbo unit, and to be fair it's not needed being like the engine has, well, a turbocharger on it.

G

is any one else finding this massivley interesting??

upload.com is way too slow I'll be uploading for weeks.

What is fast and junk free PLEASE!!

G

Photobucket.com
few ads but a good quick service

Or email them to
info@fccuk.org and we will host them