I have installed a bc cam 218,222 into a 5.3 gen 3, and I just tune to work on ve only, no maf idle adjustment etc, also already tune the transmission and feels a lot better, but I have no low end power, hits wot after 2500rpms to 3k and it runs great, do I have to modify big time the spark high octane table, can you guys point me in the right direction? Working right now so no log file many thanks.
300*2500/3456 = X*.069 = 150hp
With the OEM cam the most it can make at 2500rpm is 150hp
With an aftermarket cam:
150*.75 = 112hp
roughly you would be 20-40hp below stock with a long duration cam at 2500rpm
Where can i read more about this?Originally Posted by kingtal0n
About what? Camshaft upgrades?
Just type "what does camshaft upgrade do" In the internet search
https://www.fastcar.co.uk/tuning-tec...upgrade-yours/
..."The thing with camshafts is they generally remove performance from somewhere in the rev range to add it in another,"
Don’t think for one second that the wilder cam you go for the faster your car will be, even if it produces higher peak power numbers, as this is often not the case.
Going from a factory cam to almost any "upgrade" will generally remove low end torque and add some of that to the high end torque.
Thereby increasing top end power (or mid range) And reducing low end power (and torque)
So if the engine spends alot of time at low rpm, you make the vehicle slower by doing this, and less fuel efficient.
Gotcha, I thought it had to do with limits of the ECU. Thanks
Well you did not post any log, or tune file, so we have no way of knowing whether your issue is related to tuning, timing or fuel.
You did not post any picture or details related to diagnostics, pressure tests, timing verification, compression tests.
you did not give any details or pictures of the engine setup, placement of critical sensors and regulators.
Thus,
I am only able to give a general idea of how an engine works
Get you a stall converter that will keep you up in your power band.
The converter is the most important part of the vehicle. It must be matched to the engine, cam, differential, tire size, and driving application.
If the vehicle is "heavy" (4000lbs) and has a numerically low gear (2.73 or 3.08 for example) and less than 500hp, then it will generally need a very LOW stall converter for ideal performance and economy.
The best converter I can recommend is a "Yank" 9.5" Lockup unit. Lightweight converter 9.5" will free up rotating mass, improve response and engine acceleration, and can use a low stall if necessary (2800rpm is "lowest" Yank can make)
It's a dodge dakota 2002 XD, but you low end explanation bring me an idea besides the truck doesn't have a torque converter for the application, here in mexico we are able to get a 2500 rpm tqc, I'll try to post the log this afternoon
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