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If you notice, the "plate" sits at a huge angle.
When you bore the tb, the plate will move to an almost straight up and down position.
Then you have to adjust the tps.
The tps only cares about idle for the most part.
If the plate is closed and the tps is at its right voltage, and the map see's vacuum, the pcm will not know the difference.
Granted the tps will show 100% open before the tb is actually at 100%, but by porting it you have changed the flow quality anyways and the added flow will meet the fuel the engine is seeing, and you will still see more throttle.
The point here I guess is to fool the computer at low end and midrange, because at WOT the pcm switghes into "closed loop" and runs the engine off a set parameter any ways, so it has no clue whats going on once the tps see's 100% open.
Then you can fine tune the timing since the timing curve is pre set in the pcm and will "curve" the timing or set the timing curve exactly the same at wot every time.
So if the factory had 10 dergrees for initial timing, at WOT, the pcm's parameters may only advance the timing 15/ 20 dergrees .
So 10 + 20 = 30 degrees total timing @ WOT (example)
But your engine can handle as high as 34/ 40 degrees, so long as you have the fuel, ( since you are changing injectors, you should be fine, ) as long as the injectors can supply the extra fuel for the added air and timing.
This is why I was saying that in the past with injectors, tb, ect... I have found these engines and pcm's respond awsome to about 22 degrees initial timing at idle.
Set the timing though with the engine running and DO NOT unplug the advance for the distributor.
The pcm is stupid and will not catch you making timing adjustments to the engine.
You will want to play a little with the timing, to get it perfect, but since it has a distributor, this is pretty easy.
When you bore the tb, the plate will move to an almost straight up and down position.
Then you have to adjust the tps.
The tps only cares about idle for the most part.
If the plate is closed and the tps is at its right voltage, and the map see's vacuum, the pcm will not know the difference.
Granted the tps will show 100% open before the tb is actually at 100%, but by porting it you have changed the flow quality anyways and the added flow will meet the fuel the engine is seeing, and you will still see more throttle.
The point here I guess is to fool the computer at low end and midrange, because at WOT the pcm switghes into "closed loop" and runs the engine off a set parameter any ways, so it has no clue whats going on once the tps see's 100% open.
Then you can fine tune the timing since the timing curve is pre set in the pcm and will "curve" the timing or set the timing curve exactly the same at wot every time.
So if the factory had 10 dergrees for initial timing, at WOT, the pcm's parameters may only advance the timing 15/ 20 dergrees .
So 10 + 20 = 30 degrees total timing @ WOT (example)
But your engine can handle as high as 34/ 40 degrees, so long as you have the fuel, ( since you are changing injectors, you should be fine, ) as long as the injectors can supply the extra fuel for the added air and timing.
This is why I was saying that in the past with injectors, tb, ect... I have found these engines and pcm's respond awsome to about 22 degrees initial timing at idle.
Set the timing though with the engine running and DO NOT unplug the advance for the distributor.
The pcm is stupid and will not catch you making timing adjustments to the engine.
You will want to play a little with the timing, to get it perfect, but since it has a distributor, this is pretty easy.
!!!!! BOSCH PLUGS RULE !!!!!
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