325i 885 head modification to increase compression

[dougs87325is]

Like I said guys, Super ghetto cmon lol. If welded right anyone wjho weld might know its possible. I think I can just make the combustion chamber on the 325i head like that of the ETA head, thats all. After its weled and milled it would look pretty clean if done right. And the volume of each chamber would be somewhat close.At the same time trying to make each cylinder as close as possible in size,shape.

I would end up checking the cc in the end and try to get them as close as possible for each cylinder.

[payney8]

dont even play with it you obviously have no idea about engines or the design processes which happen before they become mass produced.

[der affe]

i have been doing cyl head work for a long time (porting, combustion chamber work, ETC) and i would not attempt to "redesign" the chambers unless you had a lot of time on your hands for trial and error and an extra engine to pull the different heads off and on to test your designs with.
you would also need some sort of monitoring and data logging to see the effects of your changes.

BMW spent LOTS of $ to design their head and chambers. granted they did make compromises to get the widest torque and horse power across the widest bands for every day driving. you can change things, but you will loose pwer in some areas to gain in other. that is just the way it is.

you can make some improvements by cleaning up the ports where there is factory casting that overlap the ports or flashing/rough casting in the chambers is one thing. major redesigning is better left to engineers or those with the time and resources to do it through trial and error.

[Fidhle007]

I know exactly what he's talking about and it won't work. There are these pesky little things called VALVES in the way...

[bataangpinoy]

fidhle,
i think hes talking about adding material and then shaping it again to create a new chamber. i read something about this a year ago on e30tech,

[Fidhle007]

spec, have you ever built a motor? Im talking about filling in areas on the combustion chamber to decrease the chamber, right. I Cant change the dang title, know how to do that? Thanks for catching that tho.

A machinist would know what Im talking about and trying to do I guess.

It doesn't really matter if he has or not because we can tell YOU sure as hell haven't... Any machinist worth their salt will laugh at you so hard they may pass out.

[bataangpinoy]

get i pistons to use on your eta rods, and shave the pistons a little bit to avoid PtV and PtH contact.

[Adrian_Visser]

This thread reminds me of that build thread in Mexico where the guy had an Evo (or some Mitsubishi I think) and the "builder" drilled holes in the pistons and carved patterns into the combustion chambers for extra horsepower. :rofl: :rofl:

Matt

Lol I recall watching some news segment on tv about some dude in India of all places who carved designs in the combustion chambers of rickshaw engines and swore it made them run better.

OP welding and grinding your combustion chamber isn't a good idea.

[E30Nova]

This thread reminds me of that build thread in Mexico where the guy had an Evo (or some Mitsubishi I think) and the "builder" drilled holes in the pistons and carved patterns into the combustion chambers for extra horsepower. :rofl: :rofl:

Matt

[jasonsnoddy]

Jason that's not even right.It's supposed to be New Mexico. The other thing I don't know what your talkin bout. I was seriously close to turning the Eta into a pick-up, amazing, your a mind reader. Props

my humble apologies, good sir.

[dougs87325is]

Jason that's not even right.It's supposed to be New Mexico. The other thing I don't know what your talkin bout. I was seriously close to turning the Eta into a pick-up, amazing, your a mind reader. Props

[george graves]

Good thread. Great thread.

[jasonsnoddy]

Im a NOOBIE

i noticed you are from mexico, is your e30 a truck

[dougs87325is]

Im a NOOBIE

[dougs87325is]

spec, have you ever built a motor? Im talking about filling in areas on the combustion chamber to decrease the chamber, right. I Cant change the dang title, know how to do that? Thanks for catching that tho.

A machinist would know what Im talking about and trying to do I guess.