How many intake valves for the Forte Gamma II engine?

I'm asking because my brother and I were discussing about the problems inherent in driving at low rpms for very extended periods of time. He has some history with Honda Civics and currently driving a Nissan Skyline.

He says that most cars with multiple intake valves keep the second one shut until at higher rpms for better performance at low rpms and lower fuel consumption. So if one intends to strictly keep to below the threshold rpm for the second intake valve for extended periods, carbon and other deposits may build-up and 'seal' the second higher rpm actuated intake valve shut. This will result in the next time when you so decide to pick up and go; your engine won't be able to.

So, once in a while, for those who are intent on saving fuel, a tankful of Caltex Tecron every couple of months and make that engine 'breathe' by putting the pedal to the metal once in a while.

But my brother and I may be wrong... Inputs anyone?

BR,
w a y

Gamma II is 16valves. How the variable valves work, I'm not too sure. But It's not the old B-series Vtec style. Probably closer to Toyota's VVT-i or Honda's i-Vtec.

The valve's opening/closing timings aren't abruptly changed because we can't feel it when the revs climb.

Hmmm... 4 cylinder engine; 4 valves per cylinder; 2 exhaust and 2 intake per cylinder head... Looks like what my brother said makes a lot of sense. Although I would not know if the second intake valve for our car kicks-in only at a higher rpm range; spec-sheets state max. torque at 4200-rpm and max power at 6300-rpm.

http://singapore.kia-global.com/user/Vehicles/Spec_New%20Cerato09.aspx?TMenuNo=5758&SMenuNo=138594&CarCode=37

"1.6 DOH C CVVT Gasoline engine
1.6-litre four-cylinder CVVT engine, which delivers maximum power of
124 ps at 6,300 rpm for a dynamic yet highly fuelefficient ride. Both
engines have dual overhead camshafts (DOHC) and hydraulic mounts to
minimise vibration, and meet stringent environmental standards for
gasoline engines.

Max. Power 124 ps / 91.2 kW @ 6,300 rpm
Max. Torque 15.9 kg.m / 156 Nm @ 4,200 rpm"

what your bro mentioned could be the 3 Stage Vtec Engine (on the 1997 or 98 civics) where the second intake valve open only above certain RPM (If i remember correctly above 2K RPM, this supposedly to save on petrol) .....

I think for Gamma engine both the intake valves work together...

muff wrote:what your bro mentioned could be the 3 Stage Vtec Engine (on the 1997 or 98 civics) where the second intake valve open only above certain RPM (If i remember correctly above 2K RPM, this supposedly to save on petrol) .....

I think for Gamma engine both the intake valves work together...

bro i think its 3000 rpm and 5500rpm for the old B block if nv remember wrongly lolx anyway wat ever it is its always healthy to push ur car once in a while to clear some carbon..

ya hor....think you are correct 3K & 5.5k RPM......

100% agreed ....once in a while muz push the engine hard to push out all the "sai"

So that means our engine 2nd stage intake valve opens at 5500rpm??

Blowing of soot is critical to keep engine "clean". Any bro can advise how long must we blow the engine at >5500rpm? Is 1 min with load okay for the theory to work knowing spore roads difficult to maintain 5500rpm for a long while.....TP watching....haha

ck7373, muff and Divine are talking about the old B series honda engine, not our Gamma II.

If you want to 'blow soot', there's no need to push the engine for 1min. 10-20secs is more than enough once in a while.

tiny wrote:ck7373, muff and Divine are talking about the old B series honda engine, not our Gamma II.

If you want to 'blow soot', there's no need to push the engine for 1min. 10-20secs is more than enough once in a while.

yeah +1 =) anyway i think the gamma 2 engine is like IVTEC leh.. varible with throttle.. cos the pull quite consistant throughtout the RPMs

Hi, what speed will we be travelling to get 5500rpm?

Did 140km/h (for a short while) in NS Highway and dun think I'd hit 5000rpm

erm bros dun mistake lay 5500rpm is for B block Vtec Honda engines.. our engines valve may be fully open at 4100 rpm cos highest torque is achieve there... IMHO

Thanks Divine,

So, for us to "blow soot", 10-20sec @ 4100rpm will do, right ?

ctoh wrote:Thanks Divine,

So, for us to "blow soot", 10-20sec @ 4100rpm will do, right ?

theortically yes

need to hit high speed? if not use gear 1 to ram can?

ctoh wrote:Hi, what speed will we be travelling to get 5500rpm?

Did 140km/h (for a short while) in NS Highway and dun think I'd hit 5000rpm

don use 1st gear ram, use 4th gear(manual) or 3rd gear(auto) push to RPM 4.2rpm .

tiny wrote:ck7373, muff and Divine are talking about the old B series honda engine, not our Gamma II.

If you want to 'blow soot', there's no need to push the engine for 1min. 10-20secs is more than enough once in a while.

Oh, paisay, read wrongly....heehee

okay, got the info to blow soot at 4100rpm for 10-20secs once in a while to "clean" engine....