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MAP vs. TPS accel

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Old Dec 29, 2012 | 03:50 PM
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Default MAP vs. TPS accel

as opposed to tracking down a 4 wire tps, why cant i just use speed density tuning? Just curious. My last rx7 was TPS tuned, so im not too familiar with the MAP based options
Old Dec 29, 2012 | 04:07 PM
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you can use map based tuning, many say that tps based is "better", i cant seem to get my car to run as well with my vtps in tp mode so i just run map based
Old Dec 29, 2012 | 05:16 PM
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MAP is fine, EAE is best.
Old Dec 29, 2012 | 08:00 PM
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I recently switched over to MAPdot because my TPS was dying. It's running great. I thought it would lag a lot more.
Old Jan 1, 2013 | 07:01 PM
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I've run MAPDot enrichment ever since I got my MS, because I don't have a TPS. It works just fine, but an authentic ballache to get done correctly. It will take a fair bit of trial and error.

There will always be a small lean/rich spike when running MAPDot based enrichment, but you can tune it to the point where it is not noticeable while driving (only by looking at the logs).
Old Jan 2, 2013 | 08:40 AM
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MAPdot vs. TPSdot is night and day in terms of smoothness and responsiveness to throttle inputs. Add in EAE and you'd never consider ever trying to tune on MAPcrap.
Old Jan 2, 2013 | 09:18 AM
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^ this is true. I wouldn't even consider MAPDot enrichment unless you absolutely have no other option.
Old Jan 2, 2013 | 12:43 PM
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Before I added a variable TPS, car ran pretty well (from a seat of the pants standpoint) with MAPdot. However, the MAP signal was noisy and the logs showed rhythmic variations in AFR due to spurious accel enrichment from the noise.

Added the variable TPS and found that the TPS signal is MUCH more stable than MAP. You can really nail the AFR's you're after and get great response to throttle movement.

.02. YMMV.
Old Jan 2, 2013 | 01:19 PM
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Originally Posted by Whizbang
as opposed to tracking down a 4 wire tps, why cant i just use speed density tuning? Just curious. My last rx7 was TPS tuned, so im not too familiar with the MAP based options
I'm assuming that if you are worried about the TPS, you're already on a speed density tune. The issue is the map sensor takes time to read the change in air flow state because the pressure does not change instantly in the plenum.
Old Jan 2, 2013 | 02:10 PM
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If you're running MS, chances are you're (99.9% of the time) running Speed Density.

The quesiton is if he wants to run MAPdot or TPSdot, which is specfically the method in which the throttle based fuel enrichments are added.

One is taking the direct throttle rate inputs and basing enrichments on it, the other is reactionary and determining the fuel enrichments based on the rate of change in MAP, is nosiey, and the least desirable method.
Old Jan 2, 2013 | 02:13 PM
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The op just seemes completely confused as to what is going on at all. Almost seemed like he wanted to run alpha-n. You don't have to tell me.
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Old Jan 2, 2013 | 02:25 PM
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the fact that he's looking for a 4-wire TPS is also worrisome.
Old Jan 2, 2013 | 09:14 PM
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I was having issues trying to get my TPS accel dialed in nicely. I found that a blend was nice. Lots of TPS accel was good for response, but would cause a very rich condition at high map / low throttle tip in. But now I'm using the accel pump feature and it's 100% TPSdot.
Old Jan 6, 2013 | 03:15 AM
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Originally Posted by Braineack
the fact that he's looking for a 4-wire TPS is also worrisome.
im just running off what the various MS threads were discussing to have a variable TPS as the stock 3 wire, and many other 3 wires are just switches.That and ones that fit will 1.6 throttle body with its half moon shape.
Old Jan 6, 2013 | 08:04 AM
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Most vTPS are 3 wire, most switches are 4.
Old Jan 6, 2013 | 08:07 AM
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Brain, since you built my MS, you might know this and save me a ton of trouble. If I get a vTPS with the same plug as the original switch, will it work work without rewiring? What's the pin mapping on the engine loom, throttle side?
Old Jan 6, 2013 | 09:16 AM
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depends how/when I made your MS. did you have to unplug your stocker in order to run?
Old Jan 6, 2013 | 09:19 AM
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I did remove it, as per your manual, but I don't know if I actually needed to. I know it is pre-wired for TPS, so I supposed as much.
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