Scylla

If I go turbo with my teg, using a DRAG III kit that came with a 12:1 Vortech FMU...would I be ok at 6-7psi? I don't think I would have the funding to pay $700-$1000 for a Hondata and tuning...is anyone running an FMU and doing okay so far?

HXMan

Hondata isn't necessary, it just makes life better.

Aeka GSR

i thought i would never get one, but the more i think about it, ill be getting one in a month.

Sonny

FMU = Soggy Hot Dog
Hondata = Sirloin Steak

Take your pick.

Sonny

Cramerox

Sonny are you a tunner?

Etylorcen

More like filet mingon. If you just run the 12:1 fmu you're going to run really rich and lose some power but yes you can just run 6-7psi w/ the kit as it is and still make lots of power. Just not nearly as much power as you could be and have it running smooth.

Sonny

I've tuned about 6 different Hondata powered cars, including my own, so yes...i guess you could say that I'm a Hondata tuner. Why? Do you need some help with your setup?

Sonny

Cramerox

well i got this turbo kit that im putting together and im almost ready to put it in. The problem is i cant decide which way to go FMU or Hondata. Hondata isnt that expensive for the reliablity that it will give but all the other little things is. ECU, harnest, tunning etc.

My main concern is that my car is a daily driver.

Have you ever tuned a car with FMU and afc?

well what ever you can advise me would be great- im open to any sugestions.

shamoo

I was skeptical at first.....but you guys who are should check out the videos on Hondata's site. There is one long 30mb one that shows you a lot. It certainly changed my mind, and as soon as I get some money together, I'm getting one.

Sonny

Before I used Hondata, I used an FMU and all of the other piggyback devices in an attempt to get my JRSC sorted out. I thought I would never use a standalone of any sort, but I got so fed up with the bandaids that I finally offed all of them and went with the Hondata.

The main problem (IMO) with your setup is your fuel pressure. Your static pressure (vacuum line from fuel pressure regulator disconnected at the regulator and pinched) will be around 45 psi. If you want to boost 8 psi, the FMU will add (8 * 12) = 96 psi on top of that. That's a max fuel pressure of 141 psi! Honda builds some tough stuff, but that type of fuel pressure is extremely hard on every component in the fuel system. Imagine what will happen if a fuel line ruptures and 140 psi of fuel pressure gets sprayed around in the engine bay. Not pretty!!

Assuming that this is your first pass at forced induction, I would kinda nibble away at things to keep it simple so that you can learn how stuff is working, get it sorted out a bit, and then move forward. Some may say, "Screw it...do it all at once." but it seems like whenever you change out a ton of things at once, a ton of problems appear.

Here's what I would do:

1) Install the kit and limit the boost to 4 psi. That will keep your max fuel pressure under 100 psi, but more importantly, it will allow you to get all of the bugs in your system worked out.

then either:

a) Install larger injectors and get a new disk for the FMU. You can idle 310cc injectors without the VAFC. You will need the VAFC for 370's and above. 310's are about 25% larger, but you'll max those out fairly quick, too. 370's cannot be idle correctly without a VAFC and control gets to be a bit messy.

b) Install 440's or 550's and a Stage 2B Hondata and get it tuned. If you sell the VAFC, you'll get enough money to pay for most of the supporting accessories for the Hondata like th OBD1 donor ECU and adapter cable.

My 2 cents...

Sonny





[Modified by Sonny, 1:11 AM 5/14/2002]

Agamemnon

Maybe think about doing the vafc hack? I think that might be safer than running the fmu. Im sure someone who knows more about this could offer you information on its reliability.

SiRkid

YOU ONLY LIVE ONCE!!!!!!!!!!!!!
think about that!
****, might aswell go all out!(cash permitting of course )

BoostedSi

v-afc hack works for me w/ 440s. I'm at 12psi.

danny

Sonny:

I was wondering a couple of things, if you would please answer them:

1) I wanted to get a hondata, I have a 94si, stock everything but just bought a greddy kit, and was wondering what do I need to get to make a hondata work( I know that I need the stage 2B, but do I need to weld anything on my stock ecu, or buy any other adapters, and I know that I need larger injectors I was thinking 440 DSM since they are cheap so i heard, but I also heard that I need to adapt them, i guess).

2) Im from Davis Ca. and was wondering if there is anyone in the bay area (san jose, sac, sf) that tunes hondata and how much that will run for. What is included in tunning also.

Thanks for your help.

Cramerox

Sonny you made some really good points. If i go with choice a). bigger injectors 310 cc- what size FMU disk would you recomend? 8:1? would i still need an inline fuel pump with 310 cc injectors?

Is there any info on the web where i can find out how much fuel presure is needed for every pound of boost?

thanks again Sonny

BTW how much you charge to tune?

Trac226

Danny, check out hondata.com, they have the locations and 411 on the shops that tune. I know that Modacar in Pleasanton are hondata tuners and I have had good experience with them.

Sonny

Hey Danny:

I went to school at UC Davis. I liked it there, but I don't miss that summer heat. blech

Since your car is already OBD1 (92-95), you can use your existing ECU and just buy a Stage 2 or Stage 2B (if you want boost) Hondata kit and be on your way.

IM me what your plans are as far as the car/engine and if you go with Hondata, I can probably locate you a good enough base map that you can get your car nailed on the dyno very quickly.

Sonny

Sonny

310cc injectors will need a 10:1 disk, so it's not that much of a drop in fuel pressure. Basically, if you increase your injector size by X%, you need to decrease the rise rate of your FMU by that same amount. 370cc injectors are about 50% larger than stock, so the corresponding FMU disk that has a 50% slower rise rate is the 8:1.

That dang Drag turbo just flows so much air. For reference, the JRSC requires "only" a 5:1 rise rate, but the CFM of the Drag is much higher and you have an intercooler, too. So, it needs more fuel.

The "VAFC Hack" that is mentioned above might work out for you, too. I don't know much about it. I know that it has been successful for some people, but as the name implies, it is a hack. Although, you're using the VAFC to do something that it wasn't designed to do and this idea hasn't been around that long, so if you get stuck, you might be stuck.

Install your kit, leave the boost at 4psi, and see how the car runs. Then, make a decision. Leave the VAFC out for now. Keep the variables to a mininum and get the thing working in a "safe" zone...then take the proper precautions to go ***** out.

My 2 cents....

Sonny


[Modified by Sonny, 7:52 AM 5/14/2002]

Cramerox

thanks alot sonny for the help in information. I'll take your advise and see how the car does with 4psi.