Grooved cylinder heads

[knighty]

check this link out

http://somender-singh.com/content/view/7/31/

and this one

http://www.gofastnews.com/board/engi...9.html#post552

looks like a nice little cheap tuning modification for 2 valve per cylinder engines

[Alex Hodgkinson]

Crikey they look a bit unsitely don't they! Seems like it could be a worker though. Not too sure about it myself. I can think of nicer ways which would have the same effect.

[GORDON STREETER]

Looks like one of Zef's modded heads after a night in the pub !
I'd like to see some "real" back to back tests on this one.

[knighty]

Originally Posted by GORDON STREETER

Looks like one of Zef's modded heads after a night in the pub !
I'd like to see some "real" back to back tests on this one.

you want real back-to-back results, here you go

http://somender-singh.com/content/section/4/37/

scroll down, if the page is blank

[Chris Y]

His site doesn't help much. There's a lot of 'seems to do this' and 'we think' that.. Smells a lot like snake oil or tiger repellant

However, it does link in with an idea I had a while back but just don't have the resources to follow up on - tapered squish pads. I thought about tapering the squish areas in towards the valves slightly - thought it may direct more of the mixture towards the plugs under compression, and help spread the flame front a bit wider. I'm probably wrong in several ways

[knighty]

snake oil.......one bloke has tried it on his briggs and stratton lawn mower engine via hacking a groove with a 1/4 inch file, and reported it now uses a 1/4 of the fuel and idles much better ........surely thats a credible enough thread for all us and all big motor manufacturers to jump on board!.........but joking aside, if someone like briggs and stratton said "yep, we''ll have it" you can have 10 cents royalty per engine, he will be a very very rich man........their engine production volumes are well into the millions.

but seriously, I think he has something, it seems to work better on some engines and not so well on others, main benefit is improved idle behaviour and emissions.......with small improvements in mid-range and max power.......I think its best suited to high compression race engines with big piston intruders that mask the other side of the chamber.

it would be interesting to see how it would perform on a highly strung 2-valve motor like a nascar engine........we shall see

[AU N EGL]

Its a FORD engine . . . They need all the help they can get.



Just Kidding . . . .

[THR]

sounds logical really... no proof above tho, its an extra op to machine in an engine, hence costs more to make, hence manufacturers aint done it!
F1 engines must have this sort of technology already, it would be something that they do all the time, esp with the camera in engine video.

[Notso Swift]

4 valve motors don't have the same issues with swirl and flame path and all that

[kelvin88]

Surely NASCAR teams has tried this already?

[gttouring]

if this was really this great, pay for the patent use would have been done by any and all manufacturers- it is such a simple idea and easy to do why not..then testing all the shapes of grooves and number of cut..hmm hmm

[phoenix]

I can see how it might achieve the claimed results.

With a two valve head and an offset spark plug, squirting a high-speed jet of mixture from the squish area across the chamber directed at the plug could give some improved mixing, increase turbulence and result in a faster flame front. This could lead to a faster and a more complete burn, equalling more power and better economy. Less ignition advance would be required to give the (higher) peak cylinder pressure just after TDC.

[dtype38]

Originally Posted by THR

F1 engines must have this sort of technology already, it would be something that they do all the time, esp with the camera in engine video.

I've seen footage of how Ferrari do it... they have a complete cylinder built of clear high pressure crystal and they just watch it with a high speed camera from outside. Nice to have that sort of money eh?

[zefarelly]

so If I just do chambers with a 4 1/2" cutting disc will I get 120 BHP/litre ?

[SidewaysFeltham]

Nope!

With such sharp edges they will start to glow and cause awful pre-ignition!

One of the reasons one tries to arrive at clean and carefully rounded head contours is to avoid precisely that.

The greater the power output: the greater the BMEP: and the higher the operating temperature inside the combustion chamber.

Of course, you could consider changing the FoMoCo mill for a Briggs and Stratton........................................

[gttouring]

i have read more on this and it seems to effect 2 valves mostly and if that-
very little research is done in the way of single modification and without rounded edges the pre-ignition would be a worry.
neat idea for the emission related rpogress but multivalve engine are the norm more so than nascar and i am sure some one in NASCAR has tried this... at WOT i am guessing this is more of a non issue rather than at idle.

[tristancliffe]

I don't believe it based on that website. Why believe any website that claims that moving the ignition point closer to TDC by running less advance gives more power, when in fact you want to run more advance to get more power (up to limits of course). And that's just one bit that's utterly wrong.

It might be true. It might work. But they haven't got a clue why, and so I will not take their word.

[GORDON STREETER]

Being the sceptic that I am I won't believe anything unless it is proved beyond doubt, under controlled conditions !