I have heard it many times before, so please don't say it again, tuning is the best option and that is my plan for the future, but I would still like some input. I have an obd0 setup, it has a firewall mounted tps sensor, and when regarding boost, how do you fool the map sensor to still read the correct vacuum signal? I heard someone in the past say something about using multiple one way check valves. Has anyone tried this? Was the outcome good? Do you have a referrence on how to do this?

 

sounds to me like that's just begging for trouble.

 

That still doesn't answer my question. I do appreciate your input on my other topics that you have helped on but it still comes down to the point.

 

basically you need to get a missing link and an FMU with a 12:1 ratio which combined will cost about 150-160 by the time you get it in the car. Its not the most precise form of fuel delivery but some people have been able to get by with it under ideal conditions.

Another option is buying a plug and play map sensor like the one hondata offers for 130 and get a tune with one of the freewares available.

either option should have a few baseline runs done on a dyno to check for a safe air fuel ratio. it wouldnt be that much more to add a freeware and have it tuned right the first time. its easier to pay a few hundred more to get it done right than have to rebuild the motor.

 

I have a RRFPR, or FMU, and the map sensor is where I come to be boggled. My MAP sensor is mounted on the firewall, not the throttle body, so the missing link idea, while it is a good idea, doesn't work for me.

 

i think you need check valves then look on granger's website they should have some.

 

Yeah, but how are they arainged?

 

They make a Missing Link for firewall mounted MAP sensors. Otherwise, just use fish tank check valves and arrange them so that they bleed off boost before the MAP sensor. You'll probably need to run 3-4 of them. Arrange them like this:

MAP_|_|_|_VAC Source

Where the vertical lines are the check valves, and everything is connected by vac hose/tees. As omniman stated, you would need a 12:1 FMU if you're running stock injectors, and you'll also need an inline fuel pump to supply the high fuel pressures you'll be seeing because of the FMU. You'll also need to retard ignition timing at the distributer(or run a boost/timing retard box) and run colder heat range spark plugs along with at least Premium grade(91-93 octane) fuel. Again, this isn't exactly an ideal fueling solution, but in the days before Hondata, Neptune, ECTune and the freeware programs became widespread, it was the only option of many people. If you're OBD-0, I would personally look into ZDyne or Turboedit, or possibly consider converting to OBD-I to run at least something like the free Crome.

 

You can go the fish tank check valve way, or you can go to your local auto parts store and pick some up. I prefer the auto parts store. I've cracked the casings of the cheap fish tank ones. Plus the auto check valves tend to relieve more boost and hold up better. Inspyral has the right "design" to follow. Also, make sure your FMU is installed properly and you might wanna consider a walboro 255 for ease of mind. I ran the walboro 255 fuel pump, votech fmu, and 3 check valves on a sohc setup that lasted me nearly 6 months until the rings gave out. Make sure you have atleast a narrow band afr gauge to keep an eye on things and you have to be selective about boosting. Can't go running around full pegged all day everyday.

 

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

MAP_|_|_|_VAC Source

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

i would have never thought to type it that way.
was about to fire up paint.

just make sure the fish valves can blow the boost out.

but as stated above, there is a missing link for the firewall mounted map.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by omniman &raquo;</TD></TR><TR><TD CLASS="quote">basically you need to get a missing link and an FMU with a 12:1 ratio which combined will cost about 150-160 by the time you get it in the car. Its not the most precise form of fuel delivery but some people have been able to get by with it under ideal conditions.

Another option is buying a plug and play map sensor like the one hondata offers for 130 and get a tune with one of the freewares available.

either option should have a few baseline runs done on a dyno to check for a safe air fuel ratio. it wouldnt be that much more to add a freeware and have it tuned right the first time. its easier to pay a few hundred more to get it done right than have to rebuild the motor. </TD></TR></TABLE>

why would you tell him he needs a different map sensor? a stock honda map will read to 11 psi acuratly and untuned he shouldne be going that high anyway. dont waste your money.

go to checker and buy (3) 1 way check valves for a vac line. put them all in line so that no boost hits the map.

install FMU, and enjoy boost until the FMU destroys your motor

 

the check valves are easy to arrange

think about it. you dont want your MAP to see boost. SO....

plumb them into your line so u can BLOW through the hose when its plugged, but cant suck any air thorough. it should instantly close.


spend $40 on a chip kit and run turboedit. done

 

No kidding. Sell the FMU, get a basemap, and you'll have the same $$$ invested, but with a greater margin of safety, not to mention MORE POWER.

There are PLENTY of weibsites that document how to add checkvalves in teh system. if you bothered to do ANY bit of research, you'll find that the checkvalves are to keep the sensor from reading boost, since it pops into limp mode if it does. Check valves only allow airflow in one direction.

If you don't want to know how to make a modern setup, then go back to the 90's and enjoy the sloppy tuning techniques. There's more than enough info from those days, don't make more useless thread on HT.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sohczcturbo &raquo;</TD></TR><TR><TD CLASS="quote"> I ran the walboro 255 fuel pump, votech fmu, and 3 check valves on a sohc setup that lasted me nearly 6 months until the rings gave out.</TD></TR></TABLE>


...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HiProfile &raquo;</TD></TR><TR><TD CLASS="quote">No kidding. Sell the FMU, get a basemap, and you'll have the same $$$ invested, but with a greater margin of safety, not to mention MORE POWER.

There are PLENTY of weibsites that document how to add checkvalves in teh system. if you bothered to do ANY bit of research, you'll find that the checkvalves are to keep the sensor from reading boost, since it pops into limp mode if it does. Check valves only allow airflow in one direction.

If you don't want to know how to make a modern setup, then go back to the 90's and enjoy the sloppy tuning techniques. There's more than enough info from those days, don't make more useless thread on HT.</TD></TR></TABLE>

+2

Read over https://honda-tech.com/zerothread?id=1544043 for an introduction into tuning.

 

a firewall mounted tps sensor? what the hell?

 

I did my research but the sites and links I found were inconclusive. I do appreciate the input you guys. I may try it, but odds are I won't. I already have a few tuning programs, I just need to socket my ECU and make a basemap. Once again, thanks.

 

quite possible... they would assume u know what a check valve is and how it works. good choice on the ecu