Author Topic: The S42 Race Engine !!!! (Read 163153 times)

r0ckrat · « **Reply #75 on:** April 08, 2008, 05:58:23 PM »

Quote from: RouteZeroDesign;46509

What happens if the flywheel disintegrates? Does it have a shield to protect the oil tank?

If the flywheel disintegrates, hopefully the engine stops as fast as it would lose oil. Do those cars really have much of a flywheel to lose anyway?

RouteZeroDesign · « **Reply #76 on:** April 08, 2008, 06:45:32 PM »

Not much of a flywheel but still, any weight spinning at 8500rpm will have a huge amount of momentum if it disintegrates.
I remember an old horror story where the flywheel on a lotus elan race car disintegrated at high rpm and parts of it ended up lodged in the roof....ever since then they run a carbon kevlar honeycomb plate around the trans tunnel

RouteZeroDesign · « **Reply #77 on:** April 10, 2008, 06:15:39 PM »

Swiss- When you go back the next time is it possible for you to get more specs on the head?
If they allow you to/if you can be bothered, could you check the volume of the ports and the combustion chamber for each cylinder?
(i can show you how, if you want)
Just a thought, as it would give us loads of information about what porting they did to the head.

Boyracer- Would any of this information be in your documents? if you dont mind me asking..

swiss318is · « **Reply #78 on:** April 11, 2008, 03:12:00 AM »

ohh...man..!!!the combustin chambers are the same volume as our..!! i asked that! they only polish the chambers and prepars the four to the same volume... the intakes and the outlets are another history..
i can ask him if i can take the cylinder head home to make some measurement..!

Boyracer · « **Reply #79 on:** April 11, 2008, 06:06:07 AM »

Quote from: RouteZeroDesign;46712

Boyracer- Would any of this information be in your documents? if you dont mind me asking..

http://www.flickr.com/photos/25412802@N07/2395594069/

There is line "Einlasskanalquerschnitt breite/h�he/radius 52 / 29.7 / R 14.85 mm"

I think that is intake port dimensions widht, height and radius since it is oval shaped

I entered the data to my excel and did some calculations (I have measured my stock M42 ports earlier, it is 51,48 / 28,17 mm)...

S42 intake port area: 1355.1 mm2
M42 intake port area: 1279.89 mm2

So if those values in document are correct, S42 has only 5.8% larger port! :eek:

Someone (swiss?) has to measure the S42 ports to be sure.

swiss318is · « **Reply #80 on:** April 11, 2008, 06:11:05 AM »

Quote from: Boyracer;46769

http://www.flickr.com/photos/25412802@N07/2395594069/

There is line "Einlasskanalquerschnitt breite/h�he/radius 52 / 29.7 / R 14.85 mm"

I think that is intake port dimensions widht, height and radius since it is oval shaped

yes... einlass means intake...

Quote from: Boyracer;46769

I entered the data to my excel and did some calculations (I have measured my stock M42 ports earlier, it is 51,48 / 28,17 mm)...

S42 intake port area: 1355.1 mm2
M42 intake port area: 1279.89 mm2

So if those values in document are correct, S42 has only 5.8% larger port! :eek:

Someone (swiss?) has to measure the S42 ports to be sure.

yes. i think i have to. due to the high demand..!:D

swiss318is · « **Reply #81 on:** April 11, 2008, 06:12:14 AM »

only 5.8% ? thats still a lot...!!

Boyracer · « **Reply #82 on:** April 11, 2008, 06:14:18 AM »

To continue the port dimensions discussion, I have S50B30 ITB's and from those you can see that S50B30 (from E36 M3) and M42 intake ports are precisely same in dimensions.

M3 3.0 puts out 95.3 hp / liter. To scale that to our 1.8 liter displacement we should be good for 171.6 hp with same port area.

The problem is that we only have 33 mm intake valves while S50B30 has 34 mm (S50B32 had 35 mm) so we have less flow. But valves can be always changed to larger

swiss318is · « **Reply #83 on:** April 11, 2008, 06:23:32 AM »

as i remember the s42 has 35mm outlet valves too...
i think the power of the s42 is a sum of the 2l displacement, low friction parts, high cr, high rpm due to titanium valves and springs.., big valves..., insane cams, solidlifters, the 8 fuelinjectors on the quillotine itb's and the better flow of the air into the cylinders..!

bigger inlet ports arent always better.. they are slower.. thats perhaps the reason why the inlets are only 5.8% bigger than stock?! the air can flow with more speed..
another reason why this engine has "nearly" no torque and no power in the lower part of the rpms

swiss318is · « **Reply #84 on:** April 11, 2008, 06:51:06 AM »

its christmas time... so complete your whish list below.. quote it and go..!

1. volume of the chambers
2. volume of intake and outlet
3. material of the valve inserts and the valves
4. weight reduction of the head?
5. pics from under the car
6. why are there caps between valveguides and head
7. cylinder head cover ventilation..
8.
9.
10.
11.
12.

Boyracer · « **Reply #85 on:** April 11, 2008, 07:36:28 AM »

Quote from: swiss318is;46774

bigger inlet ports arent always better.. they are slower.. thats perhaps the reason why the inlets are only 5.8% bigger than stock?! the air can flow with more speed..
another reason why this engine has "nearly" no torque and no power in the lower part of the rpms

Yes, too large and you lose flow velocity which hurts cylinder filling. But mere 5.8% increase in area is quite small when you think that S42 produced well over twice the power of M42

But it really seems that even stock M42 ports have plenty of spare capacity, you just need get bigger valves (and intake manifold) to use those stock ports to fullest.

Of course mild porting and smoothing of casting/CNC machining imprefections of intake port do help but they might not be absolutely neccessary until you are closer to 180-200 hp.

RouteZeroDesign · « **Reply #86 on:** April 11, 2008, 03:56:42 PM »

I <3 this thread

I think i can delete a few of these questions off the list

3. material of the valve inserts and the valves?
Beryllium for the Valve inserts and Titanium for the Valves

6. why are there caps between valve guides and head?
Titanium valves need extra cooling because titanium has a lower melting point than steel. Therefore Beryllium valve inserts are used (Beryllium 25 intake, Beryllium 3 for the exhaust) Two different types of Beryllium are used because the exhaust valve seat needs extra cooling, therefore it uses a higher percentage of Beryllium in the exhaust valve than it does in the intake.
Would you be able to verify the percentages?
The most common ratio ive seen is 98% Cu Intake, 97% Cu Exhaust)

7. cylinder head cover ventilation..
The s42 doesnt have a valve cover breather. It uses a dry sump pump which creates a vacuum in the crank case( Another reason why it makes so much power per litre).
Dry sump systems like that dont need a breather because any oil vapour is sucked down into the dry sump pump and on into the oil tank. The Tank itself has a breather tank which is used to seperate out any air from the oil.

Il post up my wish list later on, im heading out now

nuvolarossa · « **Reply #87 on:** April 12, 2008, 07:34:15 AM »

damn, I was missing this thread with pics:eek:

i'll do my wish list soon, as now I'm zooming your pics:D

thank you friend!

swiss318is · « **Reply #88 on:** April 28, 2008, 03:27:24 PM »

i found some pics of the 320i stw... the pics on the first page of this thread are from this car...

RouteZeroDesign · « **Reply #89 on:** April 28, 2008, 08:12:42 PM »

This thread is what makes me torn between the f20c and the m42/44.

There are so many factors to consider...on the plus side, if i stay m42/44 its keeping it bmw...which is a major plus.

Thanks for all youve done swiss, if it wasnt for you my mind would already be set on the honda engine