Are the only sensors/devices that control timing the CTS, ATS and CAS (and ECU obviously)? Does the MAF, 02 orTPS in anyway advance or retard timing?
Hypothetically speaking, if you were to carb a SOHC KA, you could still have the ECU control timing correct?
Not exactly...the ecu take maf, tps, and pretty much every other sensor into account when it determines what to set the timing to. For example...you punch the throttle it will advance the timing to accomodate the sudden change in airflow.
Interesting. I ask because I'm debating on making adapter plate (or box rather) to use a down draft carb on the stock intake manifold.
I would use a couple side drafts, but cost is an issue and I'm trying to get a "budget" carb setup going.
Already measured hood clearance, so that's not an issue.
So, assuming the carb is bolted to the engine and fuel pressure is lowered to accommodate a carb. The engine will control timing using the stock ECU along with the CTS and ATS?
Any suggestions or did I miss anything?
And no, its not a cali model.
dam man were the fuck have you been there are very lil people still holding it up for the Single Slammin.
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Dude I'll always be running KA-E's. Hopefully I can this going in the next week or so. I'm really anxious to get a carb on, and start tuning.
And yes, I will have pics.
Sorry, I seen this thread when it was posted but didnt have the time to reply. I have been slammed lately.
Quote:
Originally Posted by 240-kid
MAF no, it's Sole purpose is to tell the ECU how much air is being Taken in (Thats it)
This is actually incorrect if your saying that the maf does not effect timing.
Load is figured mostly using the maf actually. The only other thing that helps figure load is the tps and it dont have much to do with it.
Picture your fuel and timing maps laying on top of each other. The load is the numbers that run across the top of the table from left to right. The more air that is pulled in the further to the right you are in your load.
These tables are for a ka24e 5 speed.
Further more this is why safc's are so bad. People think that fuel is the only thing that the maf controls however you are screwing your timing beyond belief with them. Timing is 10x more important than the air fuel ratio and people screw their timing up in favor of a good afr? That is nuts!
Now back to the topic of what your wanting to do, in order for your ecu to act properly without a maf your going to have to alter the tune to shut off the mafs feed back switch. Not only does it cut fuel at 2500 with no maf (carb would fix that) the timing is reduced as well.
Now people have ran itb setups on ka's with factory ecus with the maf removed. You DO have to have a tps though weather or not your using carb or itb. Without a maf you would be lucky to get into the 15 load range. Your timing resolution is going to be horrid and the car will most likely only be able to work good at idle and wot. The tps effects timing in a couple of different ways. It tells it when to enter decell, which if you are running a carb your fuel isnt going to cut and the timing figures are based off of little to no fuel going into the engine, your possibility of burning valves and popping flames is going to increase big time, so that would need tuned as well. Your also going to have injector simulators or injectors hooked up to keep your ecu from throwing codes. Injectors running with no fuel (to lube them) are going to fail quick and end up causing codes once more. These codes will also effect timing.
I see no way that a single carb setup could be better than sequential mulit port injection, especially for this application.
All in all its a pretty cool-bad idea.
Not hating, but just giving my honest opinion that it will not work as you desire.
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