cute wee gem Posted July 10, 2008 Share Posted July 10, 2008 I know the basics pretty much, matching manifolds etc. I look at a modern 16v pent roof styled head and have no idea what to do other than smooth/match, my only tool being a die grinder what could I do to improve this kind of head (not looking at engineering something epic as I don't have the tools but feel free to add any info anyway) only thing I can think of that may be able to be improved is valve shroud. Singh grooves seems like an interesting topic but seems to be a lot of debate into whether they really do fuck all or not? - any experience? Feel free to talk about anything head tech in here as its all interesting to me. Piston/crown design etc, throw it in. I'm new to this shit so fluid dynamics etc is too complicated for me. Any tips much appreciated, I'm not too worried if I fuck it up and make less power or even make fuck all more for hours of work, just keen to give a few idea's a shot. Port and chamber finishes? I used 150g sand paper for a final finish on the ports, is polishing the actual chambers going to actually do fuck all? Port shaping has me lost aswell. Edit: add manifold design and taper throttle/runner length etc in here. All I know is longer generally means for low rpm/long for high and so on. Quote Link to comment Share on other sites More sharing options...
Spencer Posted July 10, 2008 Share Posted July 10, 2008 to start with what engine are you wanting to play with? I gotta go but if this thread doesn't get ruined this is cool shit to debate about Quote Link to comment Share on other sites More sharing options...
tortron Posted July 10, 2008 Share Posted July 10, 2008 im also ken, have a spare bike head kicking around, want to do something mad with it Quote Link to comment Share on other sites More sharing options...
kpr Posted July 10, 2008 Share Posted July 10, 2008 in the combustion chambers, id remove any pointy bits. deshield the valves if required/ possible, but try not to cut out the squish areas. ports. tidy them up. check for bumps behind the valves where seats have been machined, 4ages have some nasty ones there. in the exhaust ports, you can possibly sharpen the divider into a point, were the gasses from each valve merge. match to manifolds etc. wouldn't bother fucking with it too much more than that unless you find someone that really knows there shit about that particular head. inlet runners. the usual bell mouths, large radius will be better. rolled full 180 degrees, or 90" blended into a flat plate seems to be a good argument.... taper is all good. doesnt need to be much 1-2 degrees. no one likes to give out secrets on this, so do some shit and hope for the best. Quote Link to comment Share on other sites More sharing options...
Hemi Posted July 10, 2008 Share Posted July 10, 2008 my mate rebuilt his engine and he threw garnet sand into the runner to ports it aye bro ran his engine in at the same time aye. went reeaaal good for 5 mins then the motor seized .. dunno why , musta leaned out and detnonated or somthing aye. everyones has siad my only bit of advice and thats smooth out any casting in the chamber less sharp edges = less cahnce of pinking Quote Link to comment Share on other sites More sharing options...
Spencer Posted July 10, 2008 Share Posted July 10, 2008 1.5 degrees is the go also bellmouth 90 degree to flat plate is the f1 norm so I'd roll that if you want to make something up only talking small %hp gain but meh Quote Link to comment Share on other sites More sharing options...
Testament Posted July 10, 2008 Share Posted July 10, 2008 it really depends on the head you are starting with for anything more than basic tidying up. but if you think about it this way, its going to be easiest for the air to flow through a straight pipe, so your trying to make the short side radius as large as possible and have the port more downdrafted to the angle of the valve. but it really depends what your working with as to whether you can try to acheiive that, if there are even any gains to be made in that respect (alot of modern 4v/cyl heads are very good), which means you might be looking at stuff to do with the splitter or just very small gains that you really need a flowbench and many many hours to find. Quote Link to comment Share on other sites More sharing options...
kpr Posted July 10, 2008 Share Posted July 10, 2008 yeh i've always liked the blended into a flat plate method best. the turbo inlet manifolds ive built have always done it that way. maybe slightly off topic. but, if your going to be messing around with different trumpets at all. don't just try a few different lengths and go with what feels best. need to retune the afr after every change. makes huge difference to tune. tried some shorter and different shape trumpets on the kp the other day, this happened to afr: http://www.starletcentral.co.nz/images/kris/afr1.JPG use to be flat 12.8'ish afr Quote Link to comment Share on other sites More sharing options...
cute wee gem Posted July 10, 2008 Author Share Posted July 10, 2008 Playing with a 3sge at the moment and an old Isuzu twincam. I've got heaps of stuff to ask so I'll write some stuff up tomorrow when I have time. Quote Link to comment Share on other sites More sharing options...
Spencer Posted July 10, 2008 Share Posted July 10, 2008 if fucking with a 3s n/a go beams head or dont bother the ports are awesome on a beams 3s will never get the others even close and already setup for rwd makes life so easy Quote Link to comment Share on other sites More sharing options...
cute wee gem Posted July 11, 2008 Author Share Posted July 11, 2008 Are the beams heads really that much better? I think the later 3sge's have come a long way from the early big port engines (playing with a 3rd gen engine atm) I think a lot of the beams' power comes from the cam timing and higher comp? (11.5ish compared to 10.5ish) I also noticed the beams' valve guides don't protrude so far into the ports as the 3rd gen, and its a bit hard to tell from the photo's but it looks as though they may have a higher port angle. Heres a link with the beams ports http://www.v-eight.com/tech_forum/viewt ... hilit=3sge Heres a couple of pics of the 3rd gen engine I've got at the moment (only ones I've got on me, sorry for crappyness) http://img213.imageshack.us/my.php?imag ... 413je9.jpg http://img214.imageshack.us/my.php?imag ... 415qa4.jpg Maybe I'm just a tight cunt and don't want to fork out for a beams, but I think the 3rd gen has a fighting chance against it with a decent set of cams and manifold, timing the cams would be my main problem but adjustable gears would let a me do some trial and error. I do want to do this to a decent standard unlike most of my other engines so I might as well start with a good platform. I just don't think the older motor is that bad For my Isuzu engine I'm looking at throttle placement and injector placement along the runners. Any idea's on this? i.e injectors before or after throttle? (stand off? hah, I wish) Its not a hugely revvy engine so I'll probably make the intake as long but as straight as I can get them. Only doing a budget build so not a huge issue what I do for this engine, but every little bit helps Quote Link to comment Share on other sites More sharing options...
Spencer Posted July 11, 2008 Share Posted July 11, 2008 Are the beams heads really that much better? I think the later 3sge's have come a long way from the early big port engines (playing with a 3rd gen engine atm)I think a lot of the beams' power comes from the cam timing and higher comp? (11.5ish compared to 10.5ish) I also noticed the beams' valve guides don't protrude so far into the ports as the 3rd gen, and its a bit hard to tell from the photo's but it looks as though they may have a higher port angle. ok gen 3 is an nice head but beams just fucks it over money spent on your gen 3 to get it up to beams hp wouldve got you one easy. Moving cam timing only broadens your curve not more peak hp assuming the dailed it in bang on on the 3 and 1 point comp is only rougly 4% on gas. Also im chopped but beams is bang for buck n/a wise just fail in the heavy arse altezza shit also will hoy's 92 btcc stz carina pwns gay vectras doooort Quote Link to comment Share on other sites More sharing options...
Roman Posted July 13, 2008 Share Posted July 13, 2008 Nothing wrong with the gen 3 motor IMO. If you had a gen 2, I'd say "ditch it" but gen 3 aint so bad, fixed a lot of the gen 2 problems. money spent on your gen 3 to get it up to beams hp wouldve got you one easy. Agreed, pick one up for $1200 if you keep an eye out. beams is bang for buck n/a wise just fail in the heavy arse altezza shit Agreed. my beams car was heaps of fun, was just over a tonne. A 2 litre NA in a 1350-1400KG car, ugh, why. (well, so people can pillage them for motors etc I guess ) Quote Link to comment Share on other sites More sharing options...
cute wee gem Posted July 19, 2008 Author Share Posted July 19, 2008 I've been contemplating on the beams right from the start. Might as well do it properly since its the long term project, so I'll keep an eye out. Luckily I've done fuck all so not losing out on much. Only concerns are cam timing. I want to run itbs so I'm not sure whether to buy a motec m400 which will allow me to run vvti as well. (not even sure what they're worth, I'm guessing alot) or use MS and ditch the valve timing all together and run it locked? On another note. Polishing cranks/rods worth the effort? Is it just a case of taking casting marks off and polishing or should I leave that shit alone? Quote Link to comment Share on other sites More sharing options...
Testament Posted July 19, 2008 Share Posted July 19, 2008 if your getting a beams wouldnt you just run the factory ecu? Also I thought you could run cam timing with MS or MSII? or maybe thats only on/off like early vtec, I guess the beams is a variable system not just 2 profiles. Quote Link to comment Share on other sites More sharing options...
Roman Posted July 19, 2008 Share Posted July 19, 2008 If you're gonna ditch the VVTI (and therefore most of your powerband) dont bother with a beams motor. May as well just use the gen 3, much easier to run an aftermarket ECU with. The beams motor has a table just like fuel or ignition timing that it references to, it changes the cam angles based on rpms and AFM signal.... so it's always making the best possible torque, even at part or light throttle. There's no point adding quads (presumably for a power gain) and then throwing away a shite load of power in doing so. Quote Link to comment Share on other sites More sharing options...
cute wee gem Posted July 19, 2008 Author Share Posted July 19, 2008 My thoughts exactly. Quote Link to comment Share on other sites More sharing options...
Guest vvega Posted July 19, 2008 Share Posted July 19, 2008 ok you cunts have had your time my turn m400 and a beams out of the box no mods will get you probaby about 130-135kw @ the mods rods...get some light h beams crank..... lightened knife edged and nitraded .. make up a scraper plate setup pistons...lightest you can get C/R 13:1 ... on big cams ... or 12:1 on mild cams Cams ..... well there is good results with putting a race cam in there 300 deg @ .50" and phasing it with the vvti you will get a massive powerband and high power head....just clean it up knife edge the valve shroud etc dont make it bigger without lots of money for development its unlikly you will see a gain from it intake ...ITB's are the way to go with tuned length trumpets and out board injection dont have them flapping in the brease ethier... well shaped airbox and cold air please with a big well flowin filter exhaust...... made and tuned to the cam's your going to use expect to spend 5-10 k on the motor.....depending on what you can do yourself but with all that you will get to the 170- 200 rwkw mark or you can just turbo it and look for 400 rwkw for about the same money Quote Link to comment Share on other sites More sharing options...
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