Hey guys quick question. How and what are you controlling when tuning a Honda (hondata, crome, et all)? I understand fuel maps are key. But how does the ecu change timing? The distributer, rotor and cap are all mechanical components so how does or simply can an ECU program change that. I'm asking because I'm trying to figure out if an S300 will really be worth the investment on my NA B18B with basic bolt ons and Cams (Custom BC's similar to the Crower 404 that I am picking up used from a fellow HT member). I have been told I will be able to get a safe tune with a AFC, safe as in not the most power but you wont blow it up either. I ask because this is my track car (HPDE) so its $600 for the S300 and wait to get back on track or $300 for afc and $300 for 2 more track days.

 

With cams & bolt-ons the s300 system would work 10x better.
You will be able to adjust ignition & fuel parameters much more efficiently.

 

OK in what way is is 10X better? Can you or can you not get a safe tune using a AFC. I understand after further research that timing can be changed by a program but as this car is only driven maybe once a month and at 3-4 track events a year I have a hard time justifying spending the extra $300 on the unit and an hour on the dyno plus tuning fees (totaling around $200-$250 more). I mean if you can safely tune the car with and AFC but loose 3-4 HP I'm cool with that because it will get me back out on track that much faster. I understand its a great piece but if its not a must have right now I can always pick one up later.

Thanx for any and all info

 

AFC hack is no substitute for a good tune with rom editor. If you have a hard time trying to justify a good ems and tune for a track car then why not stay stock?

I don't know how you think a AFC hack will only be a 3 or 4 whp difference and be safe.

 

An ecu works by using vacuum columns with rpm's in open loop mode. When using a hack u are altering what the ecu thinks its receiving in order to add more or less fuel at a certain point. It cannot be fine tuned, and with that it throws your timing maps off the wall, because it will give u the wrong timing values that u really need a certain point.

 

y don't u just use crome or hondata s100 will do any of those things ur looking for, and way cheaper

 

speed density.

PV = nRT.

Map pressure vs RPM vs TPS vs compensation tables vs o2 sensor (if running closed loop). They all determine how much fuel and ignition the engine gets. The rom editor, not a piggyback, can independently control ignition timing with the same resolution as controlling fuel (same map/rpm scale).

9/10 the tuner is going to recommend something better than a vafc for a motor that needs fueling and ignition requirements outside the range of what a piggyback can do.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">speed density.

PV = nRT.

Map pressure vs RPM vs TPS vs compensation tables vs o2 sensor (if running closed loop). They all determine how much fuel and ignition the engine gets. The rom editor, not a piggyback, can independently control ignition timing with the same resolution as controlling fuel (same map/rpm scale).

9/10 the tuner is going to recommend something better than a vafc for a motor that needs fueling and ignition requirements outside the range of what a piggyback can do.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Street Rice &raquo;</TD></TR><TR><TD CLASS="quote">An ecu works by using vacuum columns with rpm's in open loop mode. When using a hack u are altering what the ecu thinks its receiving in order to add more or less fuel at a certain point. It cannot be fine tuned, and with that it throws your timing maps off the wall, because it will give u the wrong timing values that u really need a certain point. </TD></TR></TABLE>

Thanx for the explinations guys!!!!

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mar778c &raquo;</TD></TR><TR><TD CLASS="quote">AFC hack is no substitute for a good tune with rom editor. If you have a hard time trying to justify a good ems and tune for a track car then why not stay stock?

I don't know how you think a AFC hack will only be a 3 or 4 whp difference and be safe.</TD></TR></TABLE>

What exactly are you saying?
I posted this because I'm trying to learn exactly how each of these system work. I will tell you that seat time in the car is worth much more than 10-15 or even 60-70 hp (I have vids from the ITR EXPO of my 122 HP RS rolling quite a few prepped ITR's in the Advanced run group).

That being said I do now understand how the systems work and I do understand that an S300 would be the best for power and safety. But, if I pick up a used AFC off eBay (or my wife's car hehehe) and run it for a few events and later pick up a S300 that should be fine... Correct? Again I understand its not perfect but for the time being it could/would be a usable substitute?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vbspec &raquo;</TD></TR><TR><TD CLASS="quote">
What exactly are you saying?
</TD></TR></TABLE>

I thought I was being pretty clear. If you can't do it right then don't do it at all. If seat time is more important then stay stock.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vbspec &raquo;</TD></TR><TR><TD CLASS="quote">
But, if I pick up a used AFC off eBay (or my wife's car hehehe) and run it for a few events and later pick up a S300 that should be fine... Correct? Again I understand its not perfect but for the time being it could/would be a usable substitute?</TD></TR></TABLE>

IMO it would not be fine and no it is not a useable subsititute unless you want to shorten the life of your engine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mar778c &raquo;</TD></TR><TR><TD CLASS="quote">

I thought I was being pretty clear. If you can't do it right then don't do it at all. If seat time is more important then stay stock.

IMO it would not be fine and no it is not a use able substitute unless you want to shorten the life of your engine. </TD></TR></TABLE>

Wow you sir are very insightful thank you so very much for your help.

Since you seem to want to speak in very generalized statements I'll ask very direct questions and see if you will elaborate.

What are the ways of "doing it right"? As this car will be a NASA Time Trials car next year I don't have the extra points to do a stand alone. If "doing it right" is the only way to do it I guess everyone should stay stock in your opinion until they have all the parts and all the funds to buy only the best. I mean to really do it right a tunable ECU should be the first engine mod anyone does... I'm sure that's what you did to get every last once of power from any change made to the engine. Right that is what you did???

And in what way will I be shortening the life of my engine? As stated above the cars get drive about once a month on the street and about 6-8 hours a year on track. I don't see how having the timing be a little off can damage the engine. I do however understand that an engine that runs too lean is no good. I guess if I were presented with some facts or links to research/ test done to back up your opinion that would be great. But its a quick short term fix that will give the needed tunabily needed to safely change cams.

I'm thinking this way $200 AFC off eBay run it for 6 months to a year sell it on eBay next year for $175. Out only an additional $25 over going with the S300 right away.

 

a vafc cannot control ignition advance independently. It is instead a side-effect of altering the map signal.

VAFC = Vtec Air Flow Converter, it gives the map sensor a fake signal to make it believe there is more or less air coming through the throttle body thus the ecu adding or subtracting fuel, however, the map sensor also determines how much timing the engine receives and typically the opposite of what the engine really needs/wants when adding/subtracting fuel.

If the cams are not too radical, the vafc will be fine for now.

 

98vtec thanx again for your post.

After reading your first post I did a few more google searches and have a much better understanding of the subject.

Quick question on an B18B non vtec I assume that the timing is controlled the same way?

The cams are not super radical they are close to the Crower 404 and I will be replacing the springs. If this cam is a bit to much on the extreame side I may have to rethink some things.

 

there are other options... see how much your local tuner would charge you to tune on chrome... its cheaper and much better than a safc..

 

OP Read: https://honda-tech.com/zerothread?id=1544043

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vbspec &raquo;</TD></TR><TR><TD CLASS="quote">

Wow you sir are very insightful thank you so very much for your help.

Since you seem to want to speak in very generalized statements I'll ask very direct questions and see if you will elaborate.

What are the ways of "doing it right"? As this car will be a NASA Time Trials car next year I don't have the extra points to do a stand alone. If "doing it right" is the only way to do it I guess everyone should stay stock in your opinion until they have all the parts and all the funds to buy only the best. I mean to really do it right a tunable ECU should be the first engine mod anyone does... I'm sure that's what you did to get every last once of power from any change made to the engine. Right that is what you did???

And in what way will I be shortening the life of my engine? As stated above the cars get drive about once a month on the street and about 6-8 hours a year on track. I don't see how having the timing be a little off can damage the engine. I do however understand that an engine that runs too lean is no good. I guess if I were presented with some facts or links to research/ test done to back up your opinion that would be great. But its a quick short term fix that will give the needed tunabily needed to safely change cams.

I'm thinking this way $200 AFC off eBay run it for 6 months to a year sell it on eBay next year for $175. Out only an additional $25 over going with the S300 right away. </TD></TR></TABLE>

Ignore me. It's your car have fun.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vbspec &raquo;</TD></TR><TR><TD CLASS="quote">

And in what way will I be shortening the life of my engine? As stated above the cars get drive about once a month on the street and about 6-8 hours a year on track. I don't see how having the timing be a little off can damage the engine. I do however understand that an engine that runs too lean is no good. </TD></TR></TABLE>

timing is very critical... stock timing wouldnt be great at all, let alone safc'd timing that could be way too far advanced... great way to ruin a motor quick... especially during hard driving. You gotta pay to play... and this is probably the biggest case for that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dmotoguy &raquo;</TD></TR><TR><TD CLASS="quote">

timing is very critical... stock timing wouldnt be great at all, let alone safc'd timing that could be way too far advanced... great way to ruin a motor quick... especially during hard driving. You gotta pay to play... and this is probably the biggest case for that. </TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vbspec &raquo;</TD></TR><TR><TD CLASS="quote">


What are the ways of "doing it right"? As this car will be a NASA Time Trials car next year I don't have the extra points to do a stand alone. If "doing it right" is the only way to do it I guess everyone should stay stock in your opinion until they have all the parts and all the funds to buy only the best. I mean to really do it right a tunable ECU should be the first engine mod anyone does... I'm sure that's what you did to get every last once of power from any change made to the engine. Right that is what you did???

</TD></TR></TABLE>

Yeah thats how its done right! And if you know how deadly a bad tune is especially when you have more than stock power its more prone

Plus vafc would be a waist of money no body will buy it back