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Fueling Changes for GYTR Performance Cams '12'-15

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I managed to find a set of GYTR cams for the first gen of FI WR450Fs. I think (from reading the forums) that it is comparable to a stage 1 hotcam. It is uncorked and I run a powerbomb/powercore setup. Any ideas how much fuel to add to the current map? Strictly supermoto duty, running the FMF map at the moment. 

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You should not need to add any fuel, as all you are doing it opening up the valves higher and longer. 

If you ported the head, or changed the intake or exahuast, you would change the mapping.

 

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Correct me if I'm wrong, but wouldn't higher lift and or duration allow the motor to "suck in" more fuel? I thought this was the effect on my old carbed bike. There wasn't a need to rejet in that case because the greater vacuum effect pulled more fuel as well as air. With FI, the injector sprays the programmed amount of fuel each time while a greater amount of air is still being pulled, making the bike run leaner. Hence why I was wondering if I should add more fuel to the map. Thanks for any insight!

Edited by dirznut

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1 hour ago, dirznut said:

Correct me if I'm wrong, but wouldn't higher lift and or duration allow the motor to "suck in" more fuel?

it would but cams are not straight across the board like that, they move the power around by making the engine more efficient in a certain area. at lower rpm the valves are already open so long no more air can get into the cylinder, its not likely to burn up but you're fueling is likely not matching up as well. with that said If i were you i would start hunting for a motorcycle dyno shop, it should be inexpensive for at least a base run which is all you would need with the gytr tuner.

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You should get familiar with your Yamaha tuner and play around with it. You will likely notice advancing the timing gives it more zip. Adding fuel down low gives a feeling of more torque. 

It is very difficult to exactly know what it needs without a dyno and a air fuel reading. However your not too far from stock as mentioned above the GYTR lobs are just a little bigger and moved around for a tad more middle and upper power. 

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Thank you guys for the knowledge, I'll try the same map and play around with it while I look for a dyno place with an a/f ratio sniffer.

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