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Originally posted by 92b16vx@Aug 26 2003, 04:52 PM
Changing your cams won't change your crossover point.
Originally posted by cycloneb18c3@Aug 28 2003, 08:58 AM
what ecu are you using? 4800 sounds like a SOHC, a spoon chipped ecu, or that ur using a vtec controller. I dont think any stock honda program kicks the vtec at 4800 for a dohc.
Originally posted by cycloneb18c3@Aug 28 2003, 01:58 PM
what ecu are you using? 4800 sounds like a SOHC, a spoon chipped ecu, or that ur using a vtec controller. I dont think any stock honda program kicks the vtec at 4800 for a dohc.
Originally posted by 90crxb16a@Aug 28 2003, 03:54 PM
i have a pr3 on my b16 and my Vtec kicks in at 5500 rpm's
Originally posted by 90crxb16a@Aug 28 2003, 04:54 PM
i have a pr3 on my b16 and my Vtec kicks in at 5500 rpm's
Originally posted by khai_tuan_nguyen@Aug 28 2003, 06:45 PM
What is a Pr3-3 on a head? 99-00 civic si?
Originally posted by Bl6CRX@Aug 28 2003, 03:02 PM
Yeah, im not sure if id have it that low, more like 5200-5500 sounds better but besides that it would be fun to have VTEC kick in at 8 (i know its a stupid idead for performance) but when we were bored one day and started messing with my bros VAFC and made it kick in at 6500ish the cross over is intense, pulls so hard
When to Switch Camshafts
The ECU is constantly comparing the torque curves of the low and high speed camshafts. It calculates the expected volumetric efficiency of the engine based on the current environmental conditions (air temperature and pressure) and the engine conditions (temperature, engine load, throttle position), and then derives the expected torque from the volumetric efficiency for each camshaft. Most of this has to be done anyhow in order to determine how much fuel to inject.
When conditions are right (the revs are over about 4500 rpm, the engine is warm, there is enough oil pressure to activate the pistons and the car is moving) the ECU will switch from the low to high speed camshaft when the expected torque of the low speed camshaft equals the torque of the high speed camshaft.
Originally posted by omega11855@Aug 28 2003, 05:14 PM
n3g(negative) cams wont automatically change vtec point ecu cant adapt like that
but depending on load if ecu is still in closed loop vtec wont kick in neccisarily at a specified rpm for example i just drove to san fran and when i was coasting (dont ask but from la to san fran it was like 4.5hrs)(great time) at 5900 vtec didnt kick in it only kicked in if i got it to 6200 coasting ie not floored this is on a stock p73 ecu vtec point changes based on conditions but there are set parameters as i said regardless of how much throttle at 6200ish it changed over no mater what