MX6.com - View Single Post - Maximum lift of custom cams on stock valves/retainers.

**veltpak6** · 7-4-05, 19:03

I'll tell you one thing; youre taking this far more seriously than I. By FE, it's obvious I'm speaking of the FE-DOHC... not figuring that out? a work of genius in and of itself. Anyhoo... tell me how heavy rods and crankshaft, heavy hydraulic lifters and valve retainers make this engine suitable for N/A RPMs (you remember, your NA powahz is going to have to come from excessively high RPMs... right?? of course!) So yea, consider the rods and most of the valvetrain completely replaced, and you might want to consider a longer rod, with a shorter piston. If I were doing this, i would be aiming for a good 8500/9000rpm redline. Stock IM is NOT going to support that, hell the ports will have a hard time feeding the cylinders at that rate. Have you seen a smalldisplacement HONDA port lately? After that, you might just want to knife edge, lighten and balance the FE (dohc sohc tohc) crankshaft. What a waste that massive rod journal diameter is going to be, considering the low (read: yawn) crankpin forces you'll be generating. Wow, suddenly those giant journals just amount to unnessecary rotating mass. Considering you dont change the rod length, and lighten/shorten the piston, the existing 1.75:1 rod stroke ratio is pretty nice. Gives a decent balance of piston dwell and TDC accleration which will help midrange breathing (provided it's matched with a suitable intake manifold). But again, youre going NA, so it would probably be prudent to lengthen and lighten that rod and shorten that piston, inturn increasing your R/S ratio which will help reduce the angular thrust of the piston into the cylinder wall and increase TDC dwell to make efficient use of the power stroke at extreeeeeeme high RPM, yo. The H23 crank, I can nearly guarantee you, is lighter than the FE3 crank (have u seen the counterweights on it?) albeit, yes it "revs hard" to a whole whopping 7000rpm (oOooO!!) and that thing has an absolutely retarded rod/stroke ratio of 1.45:1... FRM cylinder wall lining, short skirt, lightweight pistons and A BALANCE SHAFT seem to help it get there to its astounding 160hp *yawn*. The torque is nothing to scream about either, despite its long stroke and r/s ratio. (must be that the piston out acclerates the combustion flame front close to redline.. thats smRt) ok so H23 is a bad example. No wonder Honda shortened the stroke, increased rod length and increased bore size with the higher-na-powered H22. So to sum it all up, unnessecary rotating and reciprocating mass on high RPM NA engine = BAD. Have fun porting to support your wild cams, make sure your valves can return to the seat without destroying something (see point#1), . 'Laminar flow does occur in situations with fluids of greater viscosity' and yes air is teh very low viscosity, especially travelling in a round tube to a very abrupt low frequency. Finally, you should be a bit more selective in who you are rude to, ya never know what they could end up knowing and finally the FE-DOHC fuggin rawks in forced induction applications

Good Luck, Peace!

7-4-05, 19:03	#10 (permalink)
veltpak6 Join Date: Jul 2001 Location: Toronto, Canada? Age: 28 iTrader: (0)	Way Off Topic, Yet Somehow Related Hmmm.... :p I'll tell you one thing; youre taking this far more seriously than I. By FE, it's obvious I'm speaking of the FE-DOHC... not figuring that out? a work of genius in and of itself. Anyhoo... tell me how heavy rods and crankshaft, heavy hydraulic lifters and valve retainers make this engine suitable for N/A RPMs (you remember, your NA powahz is going to have to come from excessively high RPMs... right?? of course!) So yea, consider the rods and most of the valvetrain completely replaced, and you might want to consider a longer rod, with a shorter piston. If I were doing this, i would be aiming for a good 8500/9000rpm redline. Stock IM is NOT going to support that, hell the ports will have a hard time feeding the cylinders at that rate. Have you seen a smalldisplacement HONDA port lately? After that, you might just want to knife edge, lighten and balance the FE (dohc sohc tohc) crankshaft. What a waste that massive rod journal diameter is going to be, considering the low (read: yawn) crankpin forces you'll be generating. Wow, suddenly those giant journals just amount to unnessecary rotating mass. Considering you dont change the rod length, and lighten/shorten the piston, the existing 1.75:1 rod stroke ratio is pretty nice. Gives a decent balance of piston dwell and TDC accleration which will help midrange breathing (provided it's matched with a suitable intake manifold). But again, youre going NA, so it would probably be prudent to lengthen and lighten that rod and shorten that piston, inturn increasing your R/S ratio which will help reduce the angular thrust of the piston into the cylinder wall and increase TDC dwell to make efficient use of the power stroke at extreeeeeeme high RPM, yo. The H23 crank, I can nearly guarantee you, is lighter than the FE3 crank (have u seen the counterweights on it?) albeit, yes it "revs hard" to a whole whopping 7000rpm (oOooO!!) and that thing has an absolutely retarded rod/stroke ratio of 1.45:1... FRM cylinder wall lining, short skirt, lightweight pistons and A BALANCE SHAFT seem to help it get there to its astounding 160hp yawn. The torque is nothing to scream about either, despite its long stroke and r/s ratio. (must be that the piston out acclerates the combustion flame front close to redline.. thats smRt) ok so H23 is a bad example. No wonder Honda shortened the stroke, increased rod length and increased bore size with the higher-na-powered H22. So to sum it all up, unnessecary rotating and reciprocating mass on high RPM NA engine = BAD. Have fun porting to support your wild cams, make sure your valves can return to the seat without destroying something (see point#1), . 'Laminar flow does occur in situations with fluids of greater viscosity' and yes air is teh very low viscosity, especially travelling in a round tube to a very abrupt low frequency. Finally, you should be a bit more selective in who you are rude to, ya never know what they could end up knowing and finally the FE-DOHC fuggin rawks in forced induction applications Good Luck, Peace! Last edited by veltpak6 : 7-4-05 at 19:06.
	1993 323 ZE