Im bringing this back hoping someone can give me some insight on this or maybe Vinnie can give some insight
248/232 makes peak power at 5500RPM with stock MAF this is the worst set up that you can use.232/232 makes peak power at 5800 RPM with stock MAF
What if your running a KA with a N60 MAF. I've been wanting to do this for a while so I did some research on it but nobody says anything with the maf I have
Well back from the dead.
The N60 MAF installed on 91~94 (240/248) OBD 1 engines with stock cams and and SAFC or some sort of piggy back will yield easily 10WHP without any other modification (this is ultimately the best tested set up) out of all the cam selections.
Reason is that the incoming velocity slows down the cooling process the hot wire to the MAF. Intake atmospheric oxygen by volume is greater (hence larger diameter MAF), as the MAF which is larger becomes what is velocity stacking. You can learn about this with fluid dynamic principles.
If you left all the settings at 0 on the SAFC it will lean out the engine closer to stoichiomeric at idle which is actually what you want, however higher in the rpm range without tuning it will loose power from being to leaned out, and to lean also will have the knock sensor detect knock and retard timing hindering some HP.
Since the MAF is larger you cant just tune to 0% across the RPM range. After 2800~3000 RPM the tune needs increased enrichment by 10% (to be safe) up to 7000RPM that is if the engine is bone stock, with just N60 and SAFC.
This set up requires minimum octane of 89octane, you can not use 87octane. If you want you can add more enrichment than 10% across the RPM range however then the engine guzzles more 87octane and then its more cost effective to just have it tuned out for 89octane.
Larger MAF also advances ignition timing, hence why the fuel has to be upgraded from 87 to 89 octane (minimum). ECU is fooled assuming less air, as the velocity at point of MAF is not travelling faster and denser than the velocity that travels through the intake system. Smaller MAFS are designed for emissions and richness, since the hot wire cools fast using a smaller diameter MAF the pulse width injection increases, since there is more pulse width its easier for the engine to run on 87 octane with protection of the knock sensor.
I don't agree using an exhaust 248 on intake side as the degree of angle VS timing actually has the cam react less than the 240 intake cam when in natural OEM timing placement.