Search found 32 matches

by cygnus x-1
Thu Apr 29, 2010 6:42 pm
Forum: Injectors, Fuel & Air Supply
Topic: Throttle Body size
Replies: 7
Views: 592

Re: Throttle Body size

65mm might not be all that much too big. What is the expected HP output of this engine?


C|
by cygnus x-1
Thu Apr 15, 2010 3:49 pm
Forum: Tuning Fuel and Air
Topic: horrible mpg's when can i lean out?
Replies: 26
Views: 1078

Re: horrible mpg's when can i lean out?

funny, i always justified lots of ignition timing for cruising around for really crappy, poor combustion chambers!!! Correct! And in fact my old Honda does indeed have really crappy combustion chambers. It's a 3 valve/cyl design with a hemispherical chamber, and practically no squish. As for timing...
by cygnus x-1
Tue Apr 13, 2010 7:01 pm
Forum: Tuning Fuel and Air
Topic: horrible mpg's when can i lean out?
Replies: 26
Views: 1078

Re: horrible mpg's when can i lean out?

I am REALLY surprised at how high of an RPM before the advance kicks in. I would have expected advance to climbing at 2500 to 30 degrees or so for high vacuum. Am I out to lunch, or just used to really old engines? thank you for opinions. Every engine is different but it does look like the timing c...
by cygnus x-1
Thu Apr 08, 2010 8:38 pm
Forum: Tuning Fuel and Air
Topic: Setting up AFR table
Replies: 3
Views: 490

Re: Setting up AFR table

Those AFR setting guidelines are just that, guidelines. Every engine is a little different in what it wants for AFR to create maximum HP/Torque. The difference between 12.5:1 and 13:1 is fairly small and I would bet that the dyno won't show much of a difference either. If this is a NA engine set the...
by cygnus x-1
Wed Mar 31, 2010 10:03 pm
Forum: General Information
Topic: Which MS should i use for my A18A?
Replies: 5
Views: 423

Re: Which MS should i use for my A18A?

matt & cygnus.. thanks for your info.. aprreciate it very much :D i think i will just lock the distributor.. in tight budget >.< then which one should i choose if i wanna run the fueling only..? mS2? version 3..? i will solder it myself.. I think you would only lock the distributor if you want ...
by cygnus x-1
Tue Mar 30, 2010 7:00 pm
Forum: General Information
Topic: Which MS should i use for my A18A?
Replies: 5
Views: 423

Re: Which MS should i use for my A18A?

newbie here.. i'm Lawrence from Malaysia.. there not much ppl using MS in m'sia.. so i couldn't get much info from locals.. currently driving 2nd gen 1983' Honda Prelude with stock A18A/ET1 Sohc twin carb engine.. i planned to convert to efi and turbocharge it with 4AG quad throttle & small TD0...
by cygnus x-1
Tue Mar 16, 2010 10:19 pm
Forum: Tuning Fuel and Air
Topic: Lean cruise tune for MPG.
Replies: 10
Views: 700

Re: Lean cruise tune for MPG.

How lean you can go under light throttle depends on the engine, but as a general rule for light throttle tuning, if it doesn't ping, it doesn't misfire, and it doesn't count as a pollution controlled vehicle, you're not running it too lean. I wouldn't try this above 50 kPa or so, and my Honda may h...
by cygnus x-1
Thu Dec 31, 2009 9:48 pm
Forum: General Information
Topic: megasquirt mascot + megasquirt info flyer.
Replies: 6
Views: 525

Re: megasquirt mascot + megasquirt info flyer.

Yeah, but a "squid" might help to telegraph the math skills and electronics geekiness (is that a word?) that I regularly see here on the forums. And don't get me wrong, I'm impressed and jealous of the math skills and electronics geekiness some of you have. I'm not getting the connection ...
by cygnus x-1
Tue Dec 29, 2009 7:09 pm
Forum: General Information
Topic: megasquirt mascot + megasquirt info flyer.
Replies: 6
Views: 525

Re: megasquirt mascot + megasquirt info flyer.

Hmm. I like the idea of a mascot. How about an octopus instead of a squid? They're pretty much the same thing and just seem... friendlier? If that makes any sense. I have a picture in my mind of an octopus sitting on top of a V8 with an injector in each of it's arms.


C|
by cygnus x-1
Thu Oct 15, 2009 9:16 pm
Forum: Wiring and Sensors
Topic: using thermistors instead of temp sensors
Replies: 1
Views: 258

Re: using thermistors instead of temp sensors

The default sensor in Megatune is a GM sensor. So if you can find something close to that you know it will work. There is a table in the megamanual that has the temperature and resistance values for the GM sensor.

C|
by cygnus x-1
Fri Sep 18, 2009 9:00 pm
Forum: General Information
Topic: To squirt or not to squirt
Replies: 3
Views: 682

Re: To squirt or not to squirt

I would say that tuning can definitely be challenging, but I wouldn't call it hard. It takes some patience and persistence to learn what all the settings and such are in the tuning software, but once you figure it out the actual tuning process is pretty straightforward. Really the biggest hurdle is ...
by cygnus x-1
Sun Aug 23, 2009 10:48 pm
Forum: Wiring and Sensors
Topic: Where to get a back pressure sensor for a gasoline engine?
Replies: 16
Views: 1170

Re: Where to get a back pressure sensor for a gasoline engine?

The cheapest place to get MAP sensors is a U-Pull-It junkyard. Huge selection and you can use a vacuum pump and voltmeter to map the curve if you can't find any info online.

C|
by cygnus x-1
Wed Apr 15, 2009 8:52 pm
Forum: Tuning Fuel and Air
Topic: Acceleration enrichment settings
Replies: 2
Views: 290

Re: Acceleration enrichment settings

It's mostly just trial and error, seeing what works best. I think MAP tends to be more accurate if you have a good MAP signal, but TPS is probably better if your MAP signal is very lumpy. But then if your MAP signal is that lumpy you might be better of with alpha-N fueling instead of speed density. C|
by cygnus x-1
Wed Apr 15, 2009 8:48 pm
Forum: Tuning Fuel and Air
Topic: Tuning without TPS
Replies: 2
Views: 196

Re: Tuning without TPS

I have a TPS connected but it does nothing as far as running the engine. Static fueling is based on RPM and MAP and acceleration enrichment is done entirely with X-tau, which is also RPM and MAP. I could disconnect the TPS and it would make no difference.

C|
by cygnus x-1
Fri Mar 27, 2009 9:42 pm
Forum: Tuning Fuel and Air
Topic: TPS% as base for max performance
Replies: 4
Views: 335

Re: TPS% as base for max performance

good discussion... how far would this advance be, and how do we know when we hit it? Say we shoot for 100km/hr reference speed. Do we shoot for the lowest kPa we can get while holding that exact speed? What are the safe limits... will it knock audibly while just cruising? I currently run a max of 4...
by cygnus x-1
Wed Mar 11, 2009 10:21 pm
Forum: MS-II Ignition Setup, Tuning, and Troubleshooting
Topic: EDIS 4 coil pack and trigger wheel question
Replies: 7
Views: 438

Re: EDIS 4 coil pack and trigger wheel question

I've been running without that cap for a long time and not had a problem. I can imagine it might cut down on interference with the radio though. Not a problem for me as I don't have a radio in the car.

C|
by cygnus x-1
Thu Feb 12, 2009 11:07 pm
Forum: Tuning Fuel and Air
Topic: TPS% as base for max performance
Replies: 4
Views: 335

Re: TPS% as base for max performance

Interesting observations. I'll just throw out a couple thoughts. For engine efficiency, I'm not sure air flow is going to be a reliable indicator. What you really want to look at is brake specific fuel consumption. At a given power output (speed), how much fuel is being consumed? Air is an unlimited...
by cygnus x-1
Tue Feb 03, 2009 5:51 pm
Forum: Tuning Fuel and Air
Topic: (me again ..) shifting VE-table values after changing ReqFue
Replies: 5
Views: 293

Re: (me again ..) shifting VE-table values after changing ReqFue

Looking at the fueling equation we see that Req_Fuel and VE are multiplied together: PW = REQ_FUEL * VE * MAP * E + accel + Injector_open_time So if you reduce Req_Fuel by come factor you can simply multiply the VE table by that same factor. 18/16 = 1.125 Multiply the entire VE table by 1.125 and yo...
by cygnus x-1
Fri Jan 02, 2009 9:43 pm
Forum: Tuning Fuel and Air
Topic: best lean mixture for economy
Replies: 18
Views: 1293

Re: best lean mixture for economy

Man that's lean. My Honda would run like crap with that table. Any leaner than 15.5:1 and it starts surging. 16:1 at idle would be really wheezy. But if you have an engine that can run those AFRs, go for it. Mileage would be very good. C| Hi, On the bottom of the 6th page there is a draft of an AFR-...
by cygnus x-1
Mon Dec 29, 2008 9:36 pm
Forum: Tuning Fuel and Air
Topic: best lean mixture for economy
Replies: 18
Views: 1293

Re: best lean mixture for economy

Many thanks , Ken ! NOW: something that still hurts my brain: The autosport-link it posted tells about "Pumping Losses" because the cylinder is pulling out of a vacuum at part-throttle which is harder to do than being filled by atmospheric pressure at full throttle. This causes a good par...