how to make a car rev longer?

[aznsiko]

to get it reving harder tehn you need to chip your ECU.. but again.. to rev that high the engine needs alot of work done.. because at that high the internals are put under alot of stress.. so not suggested on a stock car... wid a stock engine..

[pgclee]

go 11,000rpm!...haha...get yourself a heart attack...!!...hehehe...

dude..i reckon you don't go and do what ever 10,000rpm..there is still alot about Vtec that can make the car fast..small bucks spent may also worth the money...hehehe..

[pgclee]

modification such as...an ECU, Cam gears, fuel reg and final gear...i think you can rock on with an ITR any time...not even 2.5k including tuning and fitting...rev till 9200rpm would be fine...

[ProECU]

OK
none of these comments are totally accurate. Let me explain.

There are mainly three reasons why engines in stock form should not be revved higher than factory specs, and these reasons are the key as to what needs to be addressed if you want to go higher.

1. RODS
Power remainig constant, Piston to head clearance is chosen based on rod material stretch properties under certain rpm's. Stock rods are more than capable of revving higher, however the more rod stretch, the more likely the piston top is to kiss a valve or head, depending on the clearance. Forged rods are not a neccesity for higher revs if the clearances are adjusted accordingly.

2. Head Valve Train.
Springs & Retainers are chosen such that the spring pressure is just enough to withstand the forces generated by the cam lobe profiles at a max rpm (chosen as a function of rod & crank displacement).
Uneccesarily high spring pressures will accelerate wear on your vales & seats.

3. Engine Geometry
This pertains to the size of the crank & length of the rods.
Engine Deck Height remaining constant, the larger the crank, the smaller the rod length. The opposite holds true also.
So, a shorter rod, larger crank will cause piston speeds to be very large in comparison to the opposite scenario, and since F=ma, the forces on the cylinders are larger with shorter rods.

If you're interested in engine physics and what is required to make an engine rev higher, or produce more torque etc etc, grab yourselves a copy of "Smokey Yunnik's" engine building handbook.

Hope this explanation helps

[pgclee]

proECU...i'm starting to think that...did u learn it by paying that kinda big bucks to get the engine reving and gain your experience thru that...or you're just doing according to the theory??...hmmm....it caught me thinking that...when u say a shorter rod...hmm..means?..please define it...thank you...and also...what do you mean by bigger crank....hmm...

[rev-tech]

easiest way to rev to 10k.........get a rotor!

but if you must do it with a piston engine, well basically everything has to be balanced to perfection, if not the engine is going to shake like hell and something will get wrecked! well it will get wrecked anyway!!
The valvetrain has to cope with opening and closing at those speeds!! not to mention bearings and the likes

You want to drop the rotating mass down as much as possible as well, so a lightweight bottom end would work well.

Shane

[sifoo]

conrods, rod bolts, head bolts, a good r/s ratio and balancing is a MUST

[mj3610]

i'd be happy with 8400rpm

[destrukshn]

longer rods, more revs, less torque
shoter rods, less revs, more torque

eg.
ss v8, redline isn't high, as the strokes are longer.

but all depends on the application you want.

i'm quite sure that's how it works, if i'm wrong, please correct me.

[JohnnyVtec]

To get 10,000 you should be prepared to spend 10,000



Thats just my 2 cents worth.

Cheers,

[destrukshn]

$10,000? only?

i reckon it'd be more... lol.

[ZeForce]

shorter rods, more revs, less torque
longer rods, less revs, more torque

eg.
ss v8, redline isn't high, as the strokes are longer.

but all depends on the application you want.

i'm quite sure that's how it works, if i'm wrong, please correct me.

Its the other way around,

Long rod, compared to stroke, => high revving with narrow 'peaky' torque curve

Short rod => lower revving but with a 'broader' useful torque curve